(5arneU Uniitwatta Cihrarg Jfttrara, N«tD fork Digitized by Microsoft® Cornell University Library TH 6123.C82 1922 Princ )les and practice of plumbim 3 1924 021 428 721 Digitized by Microsoft® This book was digitized by Microsoft Corporation in cooperation witli Cornell University Libraries, 2007. You may use and print this copy in limited quantity for your personal purposes, but may not distribute or provide access to it (or modified or partial versions of it) for revenue-generating or other commercial purposes. Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® Principles AND Practice OF Plumbing By J. J. COSGROVE AUTHOR OP Sewage Purification and Disposal Sanitary Refrigeration and Ice Making Rock Excavating and Blasting Published by TECHNICAL BOOK PUBLISHING CO. SCHANTON, Pa. Digitized by Microsoft® UWIVLftf, Cf V \ . 1 . Copyright, ICtOG Standard Sanitary Mfg. Co. Copyright, KiL'i John .Joseph rusiirove Third Edition, Revised. Enlarged and Rewritten. Tenth Thousand. Digitized by Microsoft® PREFACE In preparing the manuscript for this book, the author's sole object was to systematize and reduce to an exact basis, the principles which underlie the practice of plumbing. The necessity for accurate rules and formulas, instead of the empirical methods formerly employed, was often and forcibly brought home to the author when designing plumbing installations for large buildings. The scarcity of scientific information on this important branch of sanitation was quite marked. No book had ever been published that indicated the best kind of material to use for a given purpose, that told how work should be designed and installed to be perfectly sanitary, and that showed how to pro- portion the various parts with relation to the whole, so that a plumbing system designed and installed according to the text would give perfect service. Rules and formulas for proportioning hot and cold water supply pipes were entirely lacking and no literature was available that would be of assist- ance in determining this most important feature of a building. Neither could anything be had that would indicate the size of piping required to supply a given number of flushing valves for closets, nor that mentioned the numeious other conditions requiring consideration when designing a plumbing installation. Realizing this, the author gathered much valuable data and worked out many rules and formulas from his private practice, and the gist of the rules, formulas and data have been incorporated in "Principles and Practice of Plumbing" where, for the first time, they were offered to the public. In planning the scope of the book, it was assumed that the reader knew but little of the subject of plumbing, and had no source of information outside of the book. With this premise in mind an effort was made to prepare the subject matter so clearly and concisely that a person of average intelligence, by following the text, could design and proportion any plumbing installation. That this object has in a measure been realized is evidenced by the interest of architects, engineers and plumbers in the articles when they first appeared in serial form in Modern Sanitation, and by the large domestic and foreign advance subscription for the work in book form. It is the intention of the author and publishers to keep ''Principles and Practice of Plumbing"' the standard work on plumbing and sanitation, and to this end the book will be subject to revision when found necessary. Criticism of the subject matter will be welcome, as by fair and intelligent comment its value will be enhanced. J. J. COSCROVE. Digitized by Microsoft® PREFACE TO SECOND EDITlOlSr A second edition of "Principles and Practice of Plumting" having beera called for, a complete revision of the work seemed advisable to the author. Since the book was first published, it has been accepted as the standard work on plumbing in this country, and as such is used in over fifty colleges, universities and trade schools throughout the United States-.. Such a general acceptance of the work places upon the author the responsibility of keeping the book thorough and complete in every respect, and, as many changes have taken place in plumbing practice since the original manuscript was written, and numerous queries received since the book was published, have pointed out where additional matter could be supplied, the present revision, which amounts- to a rewriting of the book, was decided upon that no> matter of value would be omitted. J.. J. COSGROVE. Philadelphia, Pa., 1914. Digitized by Microsoft® TABLE OF CONTENTS Chapter. Pace. I. The Drainage System 1 II. The House Sewer 7 III. House Drain 20 IV. Proportioning the Drainage System 28 V. Details of the House Drain 39 VI. Siphons and Slphonage 47 VII. Soil, Waste and Vent Stacks 56 VIII. Example of Djainage System 63 IX. Traps and Trapping 87 X. Blow-Off Tanks and Refrigerator Wastes 99 XI. Mechanical Discharge Systems 104 XII. Cold Water Supply 113 XIII. Solvent Power of Water 119 XIV. Hydrostatics 129 XV. Flow of Water Through Pipes 134 XVI. Measurement of Water 147 XVII. Water Hammer 156 XVIII. Water Supply Pipes 168 XIX. Cocks and Valves 178 XX. Details of Water Supply 187 XXI. Pumps and Pumping 196 XXII. Fire Lines • 212 XXIII. Purification of Waters 219 XXIV. Softening of Water 226 XXV. Sterilizing Water with Ultra Violet Rays 234 XXVI. Prevention of Rusting in Water Pipes and Tanks 238 XXVII. Hot Water Supply 244 XXVIII. Tanks for Storing Hot Water 288 XXIX. Ice-Water Supply 312 XXX. Water Supply for Suburban Places 318 XXXI. Plumbing Fixtures 340 XXXII. Swimming Pools 358 XXXIII. Appendixes 366 Digitized by Microsoft® Digitized by Microsoft® PRINCIPLES AND PRACTICE OF PLUMBING PART I THE DRAINAGE SYSTEM CHAPTER I GENERAL CONSTRUCTION Sanitation in modern building is given far more con- sideration than at any time in the history of architecture. Not only is this true in regard to the increased size of living rooms, the provision made for light and air, and the introduction of ventilation and heating systems, but more particularly in the wonderful improvements in plumbing, both as regards the drainage systems, the water supply and the fixtures. The improvements in workmanship, materials and the systems of installation have so changed the char- acter of plumbing that new standards of comparison are required to determine the quality of work. For instance, while formerly plumbing fixtures were hidden in ill-ventil- ated, poorly-lighted, out-of-the-way places, and used only as necessities, they now occupy a prominent place in the house- hold of the intelligent, and have become a luxury as well as a necessity. The improvements in fixtures consist chiefly in substitut- ing earthenware and porcelain enameled ware for the plain iron, copper and wood formerly used ; the prohibition of all mechanical closets, with their large fouling chambers, and adopting instead closet bowls with traps combined that are vitreous, non-corrosive and non-absorbent both inside and outside; the connecting of all waste pipes from fixtures with a trap placed as close to the fixture as possible, and, not least in importance, the setting of all fixtures open in- Digitized by Microsoft® 2 Principles and Practice of Plumbing stead of boxing them in wood, thus doing away with the old incubators for vermin and catch-alls for filth. The improvements in the systems of drainage within a building consist of the use of properly proportioned piping, the sizes of pipe being determined by calculation instead of by guess as of old ; the perfecting of a system of ventilation to keep the air within the drains comparatively pure; im- provement in the shapes of fittings; increased weight and better qualities of pipe used, and better methods of joining the pipes; these all contribute their share to the improve- ment of the system as a whole. Results of bacteriological investigations having shown that more disease enters a building through the water sup- ply than from the drainage system, certain precautions are taken to minimize the danger from this source. The source of the water supply is selected where there is least danger of contamination or infection, and care is taken to protect the water from pollution while in storage; also ample time is allowed for sedimentation and sunlight to remove bacteria before the water is delivered into the distributing mains. In some places the municipal supply of water is filtered through germ-proof filters before it is delivered to the con- sumers. Where this is not done separate house filters may be installed by consumers for their own protection. Example of a Drainage System. — To those who are not familiar with plumbing, there is something complicated and bewildering, about an installation, which would seem to defy analysis. Anything, however, which is based on a system, is simple when the system is understood; and as plumbing work is all done according to well defined princi- ples, the work is easy of comprehension to those who under- stand the underlying principles. In this work the effort will be made to rob plumbing of its mystery, and so present the explanation that anybody with a fair knowledge of building can properly plan work. In doing so, simple illus- trations will be used, as simple illustrations show the sys- tem followed, which can then be applied to any kind or size of installation, while illustrations of large complicated instal- lations would be so clogged with detail as to be bewildering. Digitized by Microsoft® Principles and Practice of Plumbing Digitized by Microsoft® 4 Principles and Practice of Plumbing In the illustration, Fig. 1, is shown in broken perspec- tive the general layout of a plumbing system, which includes the principal elements of any and all systems. The object here is to show the various parts in relation to the whole. The various parts will later be examined and described in detail. The drainage system, it will be seen, starts at the public sewer in the street. That portion of the horizontal drain extending to within a short distance of the foundation wall of the building is known as the house sewer. Inside of the foundation wall is a main drain trap and a fresh air inlet leading to the atmosphere outside. This trap and fresh air inlet it might be well to mention are better omitted ; but as they are required by law in some cities, they are here in- corporated as showing one of the possible elements in a system of plumbing. Continuing from the fresh air inlet there is the main house drain which is the horizontal sys- tem of piping in the basement or cellar of a building. The house drain, as in the present example, may be run under the floor, may be run above the floor, or sus- pended from the ceiling overhead. All that is necessary is to have a positive fall towards the sewer, and run the pipes as direct as circumstances will permit. Otherwise the designer can use his own judgment as to how the pipe shall be run and where it will be located, there being no par- ticular way or ways in which it must be done, nor par- ticular places in which it must be located. A floor drain is shown ready to drain the cellar floor. Floor drains are r^ advisable only in locations where their traps will always oe sealed with water, but is shown here to indicate the manner they are installed. A rain leader is shown at the rear of the building. Like the main house drain, there is no particular way to run a rain leader, so long as it is run direct as possible and with a good fall towards the sewer. At the roof or gutter, the leader is shown connected with a flexible connection. This is neces- sary to take up the variations of length due to the "creep- ing" of the leader stack. Connections are shown taken off the main house drain for rising stacks of soil and waste Digitized by Microsoft® Principles and Practice of Plumbing 5 pipe. Here, again, the simple is the right thing to do. A "Y" fitting or "TY" fitting with straight direct run to the stacks is always preferable, although a drain can be offset around an obstacle when necessary, provided there is always a good drain to the pipe. In the vertical stacks are shown three different methods of running lines. To the rear is a waste stack for the kitchen sink and laundry trays, which becomes the vent stack above the level of the fixtures. In the middle is a double line of waste pipes for a couple of lavatories located on different floors, while to the right is a stack of soil pipe with an accompanying vent stack. These stacks are all shown run close to the wall, although they may be run at any convenient place close to a partition but well away from the outside walls ; concealed in partitions, or any other part of the building, the only consideration being to keep them as much out of the way and as much out of sight as possible. It will be noticed that all of the vertical stacks of soil and waste pipes extend through the roof where they are open to the atmosphere. It will be seen, therefore, that air entering the fresh air inlet will keep flowing upward through the system of soil waste vent and leader pipes, so that the drain air within will be thoroughly diluted with fresh air from outside. It is obvious that placing a trap at the foot of any of these lines would stop the circulation through the lines so trapped, which would be very objection- able. For this reason traps are never used at the foot of any vertical lines of pipe except rain leaders when they open close to doors or windows. If the main drain trap and fresh air inlet were omitted, there would still be a circulation of air through the system, but in that case, the air would first pass through the public sewers in the street, thereby keeping the air within as freely diluted as that in the drainage system. The foregoing shows and explains the principal ele- ments of a drainage system. The system might be larger, contain ' more stacks, leaders and branches, extend up through a greater number of stories, or be modified in some way as will be explained in detail further on. No matter Digitized by Microsoft® 6 Principles and Practice of Plumbing how complicated the system may be, however, it can be divided up into the house drain; stacks of soil, waste and vent pipes ; and the fixture branches from the stacks ; and these can be laid out by remembering the few fundamental requirements for the various elements. Requirements of a Plumbing System.— First— An adequate supply of water sufficient in volume and pressure to flush all the fixtures at one and the same time. Second— Types of fixtures that are made of porcelain, porcelain enamel or some other non-absorbent material are set open, and located in well lighted, properly ventilated rooms. Third — A system having waste pipes large enough to carry off all waste matter discharged into them, yet not so large as not to be self -cleaning. Fourth — A system of ventilation so planned as to prop- erly ventilate every portion of the drainage system and provide relief in tall buildings for the heaved-up air in soil stacks when a number of fixtures are in use at the same time. Fifth — A quality of piping that will neither corrode easily nor be affected by sudden changes of temperature, and the joints of which can be made as strong as the pipes themselves. Sixth — A properly graded, perfectly gas and water- tight system that will discharge by gravity. Seventh — A system so supported throughout its entire extent, and so provided with swing joints and flexible con- nections as to take up the shrinkages, settlements and tem- perature changes of the piping and building without dam- age to the fixtures, connections, piping or buildings. Eighth — A system of installation that provides turns and offsets of easy angles; in which the branches are con- nected so as not to interrupt the flow of sewage in the main, and that provides clean-outs at such points that the inside of the drainage system is accessible throughout its entire extent. Digitized by Microsoft® Principles and Practice of Plumbing CHAPTER II THE HOUSE SEWER Plumbing systems for buildings consist of the drainage system and the system of water supply. Drainage systems include the house sewer, house drain, soil waste and vent stacks, branch fixture-connections and fixtures. Also in some cases the subsoil drainage. The house sewer is that portion of the drainage system which extends from the street sewer or other place of sew- age disposal to a point not less than five feet outside the foundation wall. It receives the discharge from the house drain rain leaders, yard and area drains, and in some cases from the subsoil drains. House sewers are generally made of tile pipe, although cast-iron pipe is sometimes used. When constructed of tile pipe, the pipe should be straight, cylindrical, smooth, free from cracks, perfectly burned, and should have a good salt glaze over the entire inner and outer surfaces, except the inside of hubs and the outside of the spigot end, which should be left unglazed, otherwise cement will not adhere to the pipe and an imperfect joint will result. Tile pipe is made in all standard sizes corresponding to iron pipe sizes up to 36 inches in diameter, and are made in several different weights. In Table I are shown the various sizes, weights and dimensions of standard weight tile sewer pipes. The sizes, dimensions and weights of double strength tile sewer pipe can be found in Table II. Ordinarily, tile pipes are made in lengths of 2 feet each, from inside of socket to end of pipe so that each length will lay just 2 feet of pipe. Special lengths of tile are made, however, 3 feet long, and these are better than the two-foot lengths for sewer purposes, as they reduce almost 50 per cent, the number of joints in a sewer. Deep and wide socket tile sewer pipes are likwise made. That is to say, whereas in ordinary standard 4-inch sewer pipe the depth of the hub is only li/^ inches, with an annular Digitized by Microsoft® 8 Principles and Practice of Plumbing space of 14 iiich between the inside of the hub and the out- side of the spigot inserted in the hub, in the deep socket pipe, the hubs of 4-inch pipe are 2 inches deep with a space of V2 inch between the inside of the hub and the outside of the pipe. This greater depth of hub and width of space makes possible a better joint so that deep wide socket tile pipes 3 feet in length would be the best to use where a water tight sewer is required. The weights and dimensions of standard deep and wide socket pipes can be found in Table III, while the weights, dimensions, and depth of sockets of double strength deep and wide socket pipes can be found in Table IV. TABLE I. Dimensions of Standard Sewer Pipe Calibre riTU;..! ^ Weight Depth Annular Inches 1 nickness per Foot of Sockets Space . Inches Pounds Inches Inches 3 M 7 Wi M 4 'A 9 w^ = 8 5 % 12 1% Vs 6 Vs 15 m Vs 8 % 23 2 Vs 9 M 28 2 Vs 10 Vs 35 2Vs % 12 1 43 2k Vi 15 1% 60 2;-^ 1-' 18 iVi 85 2M Yi 20 w% 100 3 V-i 21 13''2 120 3 1., 22 1^ 130 3 M 24 Wi 140 3 '4 \i 27 2 224 4 Vi 30 Wi 252 4 % 33 2M 310 5 13-4 36 2J^ 350 5 Ik Methods of Laying Tile Sewer. — The usual method of laying tile house sewers is to dig a trench from the street sewer to the house that is to be connected, grading the bot- tom to as nearly the required slope as possible and laying the pipe on the bottom of the trench. Where the grading is imperfectly done, the pipe must 'be blocked up in the low spots to the required grade before the joints are made. The joints are made by filling the hubs with mortar made of equal parts Portland cement and sand. When drains are Digitized by Microsoft® Principles and Practice of Plumbing 9 thus installed, the bracings under the pipes are seldom sufficient to hold the pipe in position while the trench is being filled, consequently, the joints are very apt to be broken. A good method of laying tile pipe is to so dig the trench that the bottom will have a proper and uniform grade, then, by scooping out where the hubs come, the pipe can be laid with a good bearing its entire length on undisturbed earth. This method, when properly carried out, is unquestionably the best known method of laying tile pipe, but great care must be taken in digging the trench so as not to spoil the bearing for the pipe by digging below the grade. TABLE II. Dimensions of Double Strength Pipe Weight Depth Annular Calibre per Foot of Sockets Space Inches Pounds Inches Inches 15 Wi 75 2y2 Vi 18 IH 118 2% Vi 20 If 138 3 Vi 21 iM 148 3 Vi 22 1 5/6 157 3 Vi 24 2 190 3^ Vz 27 2^ 265 4 % 30 23^ 290 4 % 33 Wi 335 5 m 36 2% 375 5 IH A quick method of laying tile pipe is to dig the trench to the proper grade and bed a line of planks firmly on the bottom ; then lay the drain on the planks. By this method the time of leveling each length of pipe is saved, also the time excavating for the hubs, and if the planks are properly graded, the drain is bound to have a proper and uniform fall. Some authorities advocate the bedding of tile pipe in six inches of concrete, but as the concrete would increase the cost of a tile drain to more than the cost of an iron one, it would be better to install an iron drain instead. Leveling Tile Pipe. — The method usually adopted for leveling tile pipe is to place an ordinary spirit level on each length of pipe as it is laid, and raise or lower th^ free end of Digitized by Microsoft® 10 Principles and Practice of Plumbing the pipe until the level shows it to be at the required grade. The objection to this method is that unless the end of each length of pipe is properly centered in the preceding hub each length might have a good fall while the entire drain might be level. A better way is to level from the hubs of the pipe. When these are properly graded and the spigot ends of each length of pipe blocked to the required height, the entire drain will have a true and uniform fall. A straight edge long enough to reach at least four of the hubs should be used to level drains. A good straight edge for this purpose can be made by cutting a straight dry piece of white pine six feet long, and jointing the edges per- TABLE III. Weights and Dimensions of Standard, Deep and Wide Sockets Calibre Inches Thickness Weight Depth Annular Inches per Foot of Sockets Space Pounds Inches Inches 4 H 10 2 M 5 'A 12 2M Vi 6 Vs 16 2H Vs 8 H 25 2% Yi 10 Vs 37 2% % 12 1 45 3 Yt. 15 IK 70 3 ■ Ys 18 1J4 90 Wi Ys 20 1^ 115 3J/2 Ys 21 iVz 130 3J^ Ys 22 iV8 145 3M ?'s 24 m 150 4 f's fectly straight and square with the sides. It should be made as much wider at one end as there will be fall in six feet of the sewer; then, by placing the straight edge on the top of the hubs with the wide end toward the outlet, the top of the straight edge will be level when the sewer has the required fall. Most tile pipes are warped a little in burning, so that the lengths are not perfectly straight. Care should be taken, therefore, when laying a tile sewer to see that the bend in crooked lengths is placed at the side and not at the top or bottom, where they would form a series of shallow pools for the retention of sewage. Digitized by Microsoft® Principles and Practice of Plumbing 11 When the tile sewers are laid on planks that are prop- erly graded, all that is necessary is to block up the spigot ends in the hubs. The pipes will need no further leveling. Tile Pipe Joints. — The usual methods of joining tile pipes is to fill the annular space between the hub and spigot with cement mortar and bank it full in front of the joint. When the inside of the hubs and the end of the pipes are unglazed, this method makes a very fair joint. How- ever, most tile pipe now made have both hub and spigot salt glazed, consequently, under such conditions, mortar will not adhere to the pipe and the joints soon leak. Salt glazed pipe can be made water-tight by first calk- ing the hub half full of oakum that has been dipped in cement grout, and then cementing the joint as in the first instance. The oakum should not be loosely packed in the TABLE IV. Weights and Dimensions of Double Strength, Deep and Wide Sockets Calibre Inchea Thickness Inches Weight per Foot Pounds Depth of Sockets Inches Annular Space Inches 15 18 20 21 22 24 1 f'/e 2 7.1 118 ■ 138 148 157 leo 334 3^ 4 H % H Vs % hub, but should be calked in hard enough to make the joint water-tight; the cement gives the joint the necessary .strength. When tile pipe joints are made with cement mortar without first calking the joints with oakum, great care should be exercised to remove any cement that might be worked through to the inside of the pipe. The cement can be removed by placing in the drain a large swab that completely fills the bore of the pipe, and drawing it along a couple of feet each time a length of pipe is laid, The pipe joints are sometimes made with asphalt; the joints are first made tight by calking with oakum and then Digitized by Microsoft® 12 Principles and Practice of Plumbing poured full with hot asphalt. For many purposes asphalt joints are preferable to cement jointsi they are lighter, more flexible, and not so likely to be broken by a settlement of the ground or by jarring of the pipe when the trench is being filled. Tile pipe joints can likewise be made with "Leadite" and will withstand an internal pressure of 5 to 7 pounds or more without leaking. Leadite is a lead-like material which is poured while in a molten condition into the hubs. Unlike lead, it expands slightly upon cooling, thereby filling all the little cavities and crevices of the hub and spigot, making them tight without calking. All that is necessary in mak- ing a Leadite joint is to calk the hub first with oakum, then pour the Leadite. Where Tile Sewer Pipe May Be Used. — Tile pipe should be used for house sewers only when a natural bed of earth or rock can be obtained to lay it on. , It should not be used even then if it is exposed to frost, discharges into a cesspool or passes near a well, spring or other source of water supply. The chief objection to the use of tile pipe for house sewers is the unsatisfactory joints between the lengths. During dry weather or in localities where the ground water is low, sewage escapes from the sewer into the earth and might wear a channel to some nearby well, cis- tern, or other source of water supply. During wet weather, or in localities where the ground water is high, water enters the sewer through the joints, a condition that might prove expensive in case the sewage is treated at a disposal plant.* Another not uncommon source of trouble from leaky joints are roots of trees that enter in search of water and in course of time completely obstruct the drain. Piping for Alkali and Acid Wastes. — Although tile pipe as a rule is not so desirable as cast iron pipe for house sewers, and is seldom satisfactory for a main house drain, there are conditions under which it is better than ordinary soil pipe, but not so good as high-silica cast-iron pipe. •At Griunell, Iowa, Mio flow of sewaKC in wot woatlier is from three to four times tlie volume of Hater pumped from tbe city w-ells. No permanent water level, steepage at deptlis varying from 10 to 40 feet, Digitized by Microsoft® Principles and Practice of Plumbing IS In chemical works, soda works, print works, plating works and other industries where iron pipe is destroyed by the acid, tile pipes will prove the better material when properly laid. In such cases the tile drain might well be bedded in concrete 6 inches thick, with 1 inch of cement mortar immediately surrounding the pipe. Where neces- sary to run vertical pipes to vats, or overhead horizontal pipes, the concrete can be reinforced and tile pipes used. This makes a costly installation and, should the joints open, the acids will attack the concrete, which then fails in time. The glaze on tile pipe will resist most commercial acids, but when the glaze is gone, the biscuit ware forming the body of the pipe proves less resistant. Cast-Iron Acid Wastes. — Soil pipe and fittings, in all commercial sizes of ordinary extra-heavy cast-iron pipe, also a special size IV2 inches in diameter, with a full line of soil-pipe fittings, are now made from high-silica cast iron, which will resist all commercial acids, but not sodas or other alkalies. The high-silica soil pipes are put out under trade names like "Duriron," and are put together with lead calked joints. Instead of oakum, asbestos rope is used as a packing. "Duriron" is an iron silicide containing about 14.5% Silicon, .870 Carbon, and .35% Manganese, and pos- sesses physical properties as follows : Melting Point about 2300 Fahr. Specific Gravity 7.00 Weight per cubic inch 0.253 lbs. Hardness (Shore Scleroscope) 49 to 51 Contraction allowance in cast 3/16" per ft. Coefficient of expansion 00001565 per deg. Fahr. Compression strength 70,000 lbs. per sq. in. Tensile strength 10,000 lbs. per sq. in. Transverse strength. , .1000 lbs. with deflection between 1/16 and Vs in. "Duriron" is a cast metal, extremely hard and close grained. It shows a white fracture and takes a high polish. It will not soften materially nor lose its shape at a tempera- ture a little below its melting point, and shows practically no oxidation at this temperature. Digitized by Microsoft® 14 Principles and Practice of Plumbing Owing to its extreme hardness, high-silica cast iron cannot be machined with cutting tools, but is finished by grinding. The high-silica pipes now on the market contain as high as 14.5% of silica. When the percentage reaches 16, the pipes will be immune to all acids. Report of a Government test on "Duriron" can be found in Table V. "Duriron" sinks, vats, kettles and other acid-resisting containers are also made. TABLE V. Report on Corrosive Tests on Duriron By U. S. Bureau of Standarfls, April 24, 1920. Cold Corrosive Tests (15» to 20° C) Duration, 120 Days. Solution and Concentration by Weight Sulphuric acid 95% Sulphuric acid 25% Sulphuric acid 10% Nitric acid 70% Nitric acid 2S% Nitric acid 10% Hydrochloric acid 25%. . . . Hydrochloric acid 5% Acetic acid 99% Phosphoric acid 87% Phosphoric acid 25% Phosphoric acid 10% Oxalic acid 7.9%* Oxahcacid2.1%t Alum 15% oryst* Picric aoid9.1%t Copper sulphate 25% orvst Animomum Chloride 27% . Ferric Chloride 48% Ferric Chloride 7% Oleic acid, comml Bromine, C. P Pyrpgallic acid 31% 37.69 66.15 35.34 66.60 64.95 35.81 65.50 65.35 66.63 56.98 36.31 36.25 67.20 66.49 66.92 64.62 37.49 85.05 65.49 36.42 65.84 65.92 35.28 cS^tS 116.5601 109.5050 103.4191 108.7927 108.4709 110.4582 107.5262 106.1607 111.936 111.7125 113.7571 111.3789 112.9180 109.4271 114.4460 103.9213 117.8332 103.1788 111.2925 113.6637 108.9583 107.4264 109.0550 oj M H .008 .018 .026 .007 .008 .000 3.078 1.234 .007 .007 .011 .009 .016 .014 .007 .005 .009 .037 .015 .018 .003 19.785 .008 — Pirj at .^ to M _l .12 .27 .40 .11 .12 .000 46.99 18.90 .11 .11 .17 .14 .24 .21 .11 .08 .13 .57 .23 .27 .05 300.14 .12 O 09 a o .007 .016 .025 .006 .007 .000 2.862 1.162 .006 -006 .010 .008 .014 .013 .006 .005 .008 .026 .013 .016 .003 18.42 .007 ffS-- 0000206 0000463 0000685 0000188 0000206 none 00805 00324 0000188 00001S8 0000292 000024 .0000412 000036 . 000018.S 0000137 .0000223 .0000977 .0000395 .0000463 .00000857 .0515 . 0000206 *Pntiirated solution at 20° C. tJ4 Sat. Sol. at 20° C. JSat. Sol. in ethyl alcohol Lead has been used to some extent for acid wastes, also lead-lined iron pipes. Lead is suitable for only a few acids, however, and there is a weak spot at every joint where the continuity of the lead lining is broken. The comparative resistance of "Duriron" and other metals to various acids is shown in Table VL This shows in Digitized by Microsoft® Principles and Practice of Plumbing 15 O U s s CS CO < OS S .2 IS o « 1-3 M Mt O 6^3 o a o i-!st . . . Philadelphia. St. Louis. — Cincinnati. . . Denver Duluth Grand Totals Averages Max. Rate in Feet per Hour 5 Min. Feet .7.5 .70 .08 .0.5 . (i.5 ■ Co . i>2 . 60 .(iO . .5(1 . .5.5 ..54 ,;'() ..50 ■IS -17 .40 -1.5 4,5 .40 .38 .30 .30 Rate of Downfall per Hour for 5 Min. 13.8726 .53 Inches 9.00 8.40" 8.10 7. SO 7.80 7. 50 7.4-1 7 '20 7.20 6.7'J (i 00 OO OO 0.60 48 6.00 0.00 5 70 .5.01 .5. 10 5.40 5 10 4., SO 4.. 50 3.00 3.60 166.32 6.40 10 Min. Inches 6.00 0.00 4.80 -1.20 0.00 5.10 7 OS 0.00 4 . !V2 4.98 (i.OO 3. no •t.SO 5 . 02 5 5S 1 SO 4 20 5 40 3 00 5.4(i 1 . 80 4 02 3..S4 4.20 3.30 2.40 128.18 4.54 60 Miu. Indies 2.00 1.30 2.18 1.25 2.10 1 78 2.20 2.15 l.fiO 1.08 2 21 1 on 1.80 1 on 2 55 1 55 1 :',4 1 . 55 1.12 1 , 5n 2 25 1.50 2.25 1.70 1.18 1.35 45.65 1.76 "Eeport o-f Ibe Chief oi: the Weather Bureau, 1896-97. A table ot lineal iuclies In deuimal fractions of a lineal foot is given in Appendix I. Digitized by Microsoft® Principles and Practice of Plumbing 31 maximum precipitation at the nearest known station may be taken, or a rate of six inches per hour assumed. The method of calculating the diameter of a drain for any locality is as follows : Multiply the area in square feet of the surface to be drained by the maximum rate of precipitation in feet per hour in that locality, and divide by 60; this will give the number of cubic feet of water to be removed per minute. Having determined this quantity, the diameter in inches of the pipe required can be found by dividing by 350, extract- ing the square root and multiplying by 12. This can be expressed by the formula : d := 12 ^/_?_P-, in which d =: diameter of pipe in inches, a = square feet of if 21000 area to be drained, p ^ maximum rate of precipitation in feet per hour, 21000 = 350 X 60. Example — What size of drain will be required in Kansas City to drain a roof and other impervious surfaces 40 X 200 feet, the drain being laid at a grade of % inch to the foot? Solution — The area a to be drained = 40 X 200 = 8000 square feet. The maximum rate of precipitation for Kansas City (see Table IX) is 7.8 inches =^-^ or .65 foot per hour. Therefore, d = 12 J SOOO X ^ ■ The 12 y 21000 square root of -^^-- = -496, and 12 X -496 = 5.952 inches, the diameter of the pipe required to drain 8000 square feet impervious surface in Kansas City. That is practically a 6" pipe. Drains are sometimes laid at grades which produce greater or less velocities than 270 feet per minute ; when so laid, the capacities of the pipes can be easily ascertained by referring to Table X, which gives the velocity of flow and the number of cubic feet discharged per minute by specified sizes of pipes when laid at different grades. ,When the area of impervious surface to be drained, the maximum rate of precipitation, and the grade at which drain is to be laid, are known, the quantity of storm water to be removed can be calculated and the size of pipe required to remove it can then be found by this table. Digitized by Microsoft® 32 Principles and Practice of Plumbing TABLE X. Capacity of Drains Running Full Velocity in feet per minute as determined by the formula v^S.OOO V vfl and discharge In cubic feet per minute by the formula Q=:V A of drains laW at different grades when running full. In which V ^velocity in feet per minute A^area of pipe in feet hrzihead in feet l:=length of the pipe in feet a=;diameter of the pipe in feet Diam. 2 Inches 2}4 Inches 3 Inches 4 Inches 5 Inches 6 Inches Fall Ft. in Ft. Is II IE i3£ 1^ Is IS i 2 a 6l I! la's Is II si fl .2 3 ■9 3 B el lin 20 273 5.46 297 8.91 335 13.40 390 32.40 432 58.32 480 93.60 lin 25 246 4.92 273 8.19 300 12.00 345 28.64 387 52.25 450 87.75 lin 30 220 4.40 249 7.49 270 10.80 312 25.89 351 47.39 390 77.65 lin 35 204 4.08 228 6.84 250 10.00 288 23.80 324 43.74 360 70.20 lin 40 192 3.84 216 6.48 237 9.48 272 22.68 306 41.31 330 64.35 lin 46 180 3.60 201 6.03 222 8.88 255 21.16 288 38.88 315 61.42 lin 50 174 3.48 192 5.76 210 8.40 243 20.17 272 36.72 300 58.50 lin 60 153 3.06 174 5.22 190 7.60 216 17.93 245 33.07 270 52.65 1 in 70 144 2.88 162 4.86 177 7.08 204 16.93 229 30.91 252 49.14 lin 80 135 2.70 150 4.50 165 6.60 198 16.43 210 28.35 214 45 03 lin 90 129 2.50 144 4.32 156 6.24 180 14.94 201 27.13 222 43.29 1 in 100 120 2.40 135 4.05 150 6.00 170 14.11 192 25.92 210 41.16 Diam. 7 Inches 8 Inches 9 Inches lOInches 11 Inches 12 Inches i > S-g i i ^1 AS Q-S lin 20 510 135.15 540 189 573 252 1)20 335 690 455 750 r,s5 lin 2£ 480 127.20 480 168 510 224 540 292 570 376 600 4uS lin 30 438 116.07 450 158 471 207 510 275 .■)20 343 540 420 lin 35 390 103.35 408 143 441 194 456 24G 480 316 510 397 1 in 40 363 96.19 390 137 411 180 432 233 450 297 480 374 lin 45 342 90.68 360 126 390 172 405 218 430 2S3 450 351 lin 50 327 86.65 345 120 363 100 390 210 410 270 420 327 lin 60 288 76.32 309 108 330 145 345 186 300 238 390 304 lin 70 270 71.55 280 98 306 135 324 175 340 224 360 230 lin 80 252 06.78 270 94 294 123 309 167 325 214 330 257 lin 90 240 63.60 268 90 273 120 285 154 300 198 315 245 1 in 100 221 58.50 245 86 258 114 270 146 288 190 300 234 Note— To determine discharge in U. S. gallons multiply cubic feet by 7.3 Digitized by Microsoft® Principles and Practice of Plumbing 33 Example — What size of drain will be requii-ed in Kansas City to drain a roof and other impervious surfaces, 50 X 200 feet, with the drain laid at a grade to produce a velocity of about 270 feet per minute? Solution — Area to be drained, 10,000 square feet X maximum rate of precipitation, .65 foot per hour = 6,500 cubic feet per hour = 108 cubic feet per minute. From Table X is found that an 8-inch pipe laid at a grade of 1 to 60 will discharge 108 cubic feet of water per minute, at a velocity of 309 feet per minute. As this rate of flow is well within the permissible range of velocity, an 8-inch pipe may be used if laid at a grade of 1 to 60. Determining the Size of House Drains. — A house drain must carry off the greatest amount of storm water likely to be discharged into it, without filling and running the danger of overflowing. If there are no openings in the cellar, however, smaller pipes will carry off the water, for the moment a hydraulic head begins to build up, it will be converted into velocity head, thereby increasing the capacity of the pipe proportionately. The size of house drains in systems from which rain water is excluded is determined by the number of inmates in the building and the per capita consumption of water. It is obvious that the amount of sewage flowing through a house drain cannot exceed the amount of water used in the building, therefore the house drain need only be large enough to carry off the greatest probable amount of water that will be used at any hour of the day. The per capita consumption of water in many of the New York State hospitals average at present from 150 to 200 gallons of water daily. In the principal cities through- out the United States the per capita daily consumption of water varies from 36 to 300 gallons, with an average from all the cities of 121 gallons. On the whole, it would seem that a per capita allowance of 100 gallons daily would be sufficient, and at the same time not too much. A study of Table XI shows that in but few cities does the per capita supply fall much below 100 gallons daily, and in those cities that do, all of which are manufacturing cities, it is reason- able to suppose that a large percentage of the people do not have elaborate toilet facilities. In the large cities, on the other hand, where from 150 to 300 gallons of water per capita are used daily, allowance must be made for water Digitized by Microsoft® 54 . Principles and Practice of Plumbing used for fire purposes, street sprinkling, flushing of sewers, etc., which would bring the average consumption of water within buildings for domestic purposes down to about 100 gallons per day. Of this 100 gallons, not over 25 per cent, will be used during any one hour of the day, and that prob- ably will be used at the hour that people arise. It will be used as follows : Water closets 6 gallons Preparation of meals, etc 2 gallons Laving 2 gallons Bathing 22 gallons Scattered 22 gallons Total 25 gallons Fifty-five gallons per hour equals .416 of a gallon per minute; therefore, to find the amount of water to be removed by a house drain under the foregoing conditions, multiply the number of inmates the building is designed to accommodate by .416 of a gallon, and the product will be the quantity of water or sewage in U. S. gallons to be removed per minute. The size of pipe required to take care of this amount can then be found in Table X or by the formula : d z= 234 V^u^' '" which d = diameter of pipe in feet, q = cubic feet of sewage delivered per second, h = head in feet, 1 = length of pipe in feet. Example — What size house drain will be required in a hotel built to accommodate 300 guests and servants, the daily per capita allnwaiiee of water being 100 gallons, and the drain to be laid at a grade to produce a veloiity of about 270 feet per minute? Solution— 300 X -416 = 124.8 gallons, or ^^'^'^ = 16.6 cubic feet of sewage per minute to be disposed of. From Table X it is found that a 4-inch pipe, wbeii laid at a grade of 1 to 40, will discharge about 22.68 cubic feet of water peiv minute. The size of house drains in buildings is sometimes determined by the following empirical rule: Rule — Allow one square Inch ni sectional area of the drain for each ttvo cubic feet, or fifteen U. S. gallons of sewage to be removed per minute. Digitized by Microsoft® Principles and Practice of Plumbing 35 TABLE XI. Per Capita Consumption of Water FEB CAPITA DAII-Y WATER CONSUMPTION IN THE TIFTY LAKOKSiT CITIES OP THE UNITED STATES, ARRANGED IN ORDER OF POPUIiATION. Cities Per Capita Consumption in Gallons 1890 1900 Increase or Decrease in Consumption in Ten Years in Gallons Incr. Deer. 1 . New York . . . 2. Chicago 3. Philadelphia.. 4. BrooldjTi 5. St. Louis 6. Boston 7. Baltimore 8. SanFran-cisco. 9. Cincinnati. . . . 10. Cleveland 11. Buffalo 12. New Orleans. . 13. Pittsburgh. . . . 14. Washington. .. 15. Detroit 16. MUwaukee 17. Newark 18. Minneapolis.. 19 . Jersey City . . 20. Louisville 21. Omaha 22. Rochester.... 23. St. Paul 24. Kansas City. . 25. Providence. . . 26. Denver 27. Indianafiolis. . 28. Allegheny — 29. Albany 30. Columbus 31. Syracuse 32. Worcester .. . 33. Toledo 34. Richmond. . . 35. New Haven.. 36. Paterson 37. Lowell 38. Nashville 39. Scranton 40. Fall River... 41. Cambridge... 42. Atlanta 43. Memphis 44. Wilmington... 45. Dayton 46. Troy 47. Grand Rapids 48. Reading 49. Camden 50. Trenton 79 140 132 72 72 80 94 61 112 103 186 37 144 158 101 110 76 75 - 97 74 94 66 60 71 48 "7i ,230 '78 68 59 72 167 135 128 66 146 '29 04 36 124 113 47 125 '75 131 62 116 190 229 159 143 97 73 121 159 233 48 231 185 140 '80 94 93 160 100 176 83 67 62 .=14 300 79 loi 230 102 70 119 100 150 129 S5 140 36 79 84 125 90 62 183 156 92 280 37 50 97 87 63 3 12 7 56 47 11 S7 27 18 18 63 26 S2 17 7 152 3-1 11 37 15 1 19 15 48 1 15 58 '17 149 37 15 30 Digitized by Microsoft® 36 Principles and Practice of Plumbing Example — What size pipe will be required to remove 108 cubic feet of water per minute when the drain is laid at a grade to produce a velocity of about 270 feet per minute? Solution— 108 -^ 2 := 54 square inches area, and from Table XIV it will be seen that a pipe of about 8% inches diameter has the required area. An 8-inch pipe, therefore, would be used. It is often desirable to know the capacity of drains when running half full. Having the velocity of flow under such condition, the capacity can easily be determined. The velocity of flow in drains or pipes running partly full can be found by the formula : V=:J— 2d, in which V = velocity in feet per second, a = area of water in ' P square feet, p = wetted perimeter in feet, 2d = twice the slope in feet per mile. Example — What is the velocity of flow in a 6-inch drain laid at a grade of % inch per foot when running half full? Solution — ^There is a llO-foot fall in a mile of drain laid at a grade of Vi inch per foot. Then V = 098 V.75 X 220 = 5.3 feet per second. Answer. In Table XII will be found the areas of roof or other quick-run-off surface that can be drained into house drains or leaders of various standard sizes of pipe, laid at grades of 14 iiich and V^ inch to the foot. TABLE XII. Size of House Drains for Roof Drainage Diameter of Pipe, Fall, Fall, Inches ii inch to the foot H iil<*ll to the foot 3 1,200 square feet 1,. 300 square ftet 4 2,500 " 3,200 " 5 4,500 " 6,000 " 6 8,000 " 10,000 " 7 12,400 " 15,600 " 8 18,000 " 22,500 " 9 25,000 " 31,500 " 10 41,000 " 59,000 " 12 69,000 " 98,000 " Drainage of Storm Water. — The rainfall on imperv- ious surfaces reaches the sewer as fast as it falls. A differ- ent condition obtains, however, when the rain falls on earth. Digitized by Microsoft® Principles and Practice of Plumbing 37 Then the amount of storm water to be carried off, and the size of drains for the purpose, will depend upon the rate of precipitation per hour; pitch or slope of the area to be drained ; area of the drainage surface ; and the quantity or proportion of the rainfall that will reach the sewer in a given time. According to Table IX, the greatest rate of downpour is 2.55 inches per hour, and the average is 1.75 inches per hour. TABLE XIII. Carrying Capacity of Sewer Pipe GALLONS DISCHARGED PER MINUTE oT -.3 ■*^ -f> -t^ °a :=!g si ;=! ?, ,— . tJ ^ QJ ^ (U -^ V Ol-i &^ ^S &^ !& ^& |g gg K ■s§ ^° ■ss •ss tS tS o.-t 5^ =4 p. ^s 5 " 1 V 1" 1 V « ft CO ft CO a a ft A ft ^ Flashing for cow ciiumto ed from the ceiling beams, a strong iron hanger should be placed on the drain close to the stack and when possible to place two hangers, one on each side of the stack, it should be done. Besides supporting stacks at their base they should also be supported at each floor of the building by heavy iron hangers or clamps securely fastened to the side walls or floor beams. Pipe hooks may be used in small frame buildings, but should not be used in buildings over three stories in height.. Material for Stacks. — Cast-iron hub-and-spigot pipe is generally used for soil waste and vent stacks in buildings Digitized by Microsoft® 86 Principles nnd Practice of Plumbing that do not exceed 65 feet in height. In buildings of greater height, wrought-pipe drainage systems are generally in- stalled. The recommending features of this system of piping are, greater and more uniform strength of the pipe, less number of joints, greater strength and permanence of the joints, greater range in the size of pipes and fittings and greater flexibility of the pipes and of the system as a whole. Wrought-pipe drainage systems differ from other drainage systems only in the materials of which they are constructed and the method of working the materials. Digitized by Microsoft® Principles and Practice of Plumbing 87 CHAPTER IX TRAPS AND TRAPPING Siphon Traps Classification op Traps. — Traps are fittings used to prevent the passage of air or gas through a pipe without materially affecting the flow of sewage. To successfully perform the functions for which they are intended, traps must be so constructed or protected by vent pipes that they' cannot be siphoned or have their seals forced by back press- ure under any conditions that obtain in a well constructed drainage system. Furthermore, they should be self-scour- ing at each flush of the fixtures to which they are connected, and should contain sufficient depth of water to withstand loss by evaporation for a long period of time without break- ing the seal. There are two types of fixture traps commonly used, siphon traps and non-siphon traps. The simplest type of trap is the running trap of siphon type shown in Fig. 42. It consists of a downward dip in a pipe which fills with water and thus prevents the passage of air. As this water seals the pipe to the passage of air or gases, it is referred to as the seal of the trap. The seal of this form of trap is formed by the column of water a, and is seldom over 1% inches in depth. It is not a good trap for the reason that it is only capable of withstanding a back pressure of .063 pound per square inch. If greater pressure is applied the water will back up sufficiently in the horizontal inlet to allow drain air to blow through the seal as indicated. The height h to which water raises in the inlet end of the trap deter- mines the amount of back pressure required to force the seal. The form of siphon trap most generally used is shown in Fig. 43. It is known as a half S, or P trap. When sub- jected to back pressure the water in this trap backs up in the vertical inlet leg and reaches a height 6 of 3V^ inches before drain air can blow through. This water column will Digitized by Microsoft® 88 Principles and Practice of Plumbing Fig. 42 Running Trap withstand a back pressure of .126 pound per square inch, or- double the back pressure a running trap will stand. SiPHONAGE OF TRAPS. — The water from a trap may be siphoned in either of two ways ; first, by self-siphonage, and sec- ond, by aspiration caused by the discharge of other fixtures. As a matter of fact, there is no dif- ference between the siphonic actions in' the two cases, as they are both due to the fact that the long leg of the siphon is flowing full of water, or water with air so entrained that it acts as a plunger of water. When the water is siphoned by self-siphonage, the water flowing from the fixture fills the waste pipe to the soil stack, and in that way starts the siphonic action which empties the trap. When a trap is siphoned by the discharge from another fixture, the other fixture must be located on a higher floor; then when the discharge of water passes the branch entrance for the fixture lower down, it fills the stack full, thereby forming a long leg from the trap and waste pipe. A trap can lose its seal from self-siphonage only when the waste pipe from the trap to the stack is unventilated and ex- tends below the bottom level of the dip a of the trap so as to form the long leg of a siphon as shown in Fig. 44. If the waste pipe extends directly back to the main stack, as shown in Fig. 45, Fis. 43 without dipping below the bot- "•!'* s Trap torn of the dip, the trap could not be self-siphoned because there would be no long leg; and, provided no fixtures dis- charged into the stack above where the waste connects, no back vents would be required for the trap. Loss OF Seal by Momentum. — Theoretically, a trap may lose its seal by momentum. If a trap is placed directly beneath a fixture, but some distance below it, a flush of Digitized by Microsoft® PHnciples and P?-actice of Plumbing 89 Fig. 44 Sell Sipbonage water might acquire sufficient momentum to carry it through the dip of the trap and into the waste pipe beyond. As a matter of fact, however, there are modifying condi- tions to prevent such loss. Most fixtures as now made have outlets so obstructed by strainers or cross- bars that the outlets are of less area than that of the waste pipe, consequently the pipe could noc fill full bore and the velocity would hardly be sufficient to acquire the necessary momentum. If it did, no harm would result, as sufficient water would adhere to the long inlet pipe and to the sides of the fixture to again seal the trap. Nevertheless, traps should be placed as close to fixtures as pos- sible, not only to prevent possible loss of seal by momentum, but also to avoid a long stretch of untrapped waste pipe. SiPHONAGE BY ASPIRATION. — When unvented siphon traps are used, a trap on one floor of a building may be siphoned by water discharged into the stack from a fixture at a higher level, as shown in Fig. 46. This is called siphon- age by Aspiration. The water discharged into the stack at the higher level, in passing the branch to the fixture at the lower level, turns the soil pipe into a long leg for the siphon trap of the lower fixture, as can be seen by the illustration, and loss of seal results. Evaporation of Water from Traps. — From experiments made by Dr. Unna, Municipal Engineer of Cologne, to determine the length of time required to destroy the seal of traps by evaporation, it can be calculated that under ordinary conditions the seal of an unvented siphon trap with a 13/^,-inch depth of seal will be destroyed in from four and a half to five weeks' time. Fig. 45 Half S Trap Connection Digitized by Microsoft® 90 Principles and Practice of Plumbing ^Z7 It may be stated, as a general rule applicable to all types of unvented traps, that under ordinary conditions such as obtain in a well-constructed drainage system, the rate of evaporation will average .4 of an inch per week, irrespective of size or shape of the surface exposed. No experimental data are available to show the rate of evaporation of water from ventilated traps, but it would be safe to assume a rate of .8 of an inch per week. Non-Siphon Traps. — Non- siphon or refill traps are those in which the seal cannot be entirely destroyed by siphonic action under any reasonable condition of cir- cumstances likely to prevail in a well-installed drainage system. Part of the seal can be siphoned from a non-siphon trap, but suf- ficient water always remains to effect a seal. The effect of siphonic action on a drum trap, which is a simple form of non-siphon trap, is shown in Fig. 47. When a partial vacuum is created in the waste pipe, atmos- pheric pressure forces part of the seal from the trap. When, however, the water in the trap reaches a certain level, no reasonable amount of siphonic influence can lower it more ; air then breaks through the seal, dashing the water to all sides. After the vacuum is broken, from all sides of the trap the water settles back in the bottom, thus main- taining the seal. Sufficient water always remains in the bottom of this form of trap to effect a perfect seal. All forms of non-siphon traps are made with enlarged bodies, some of which contain baffle plates to deflect the water from the outlet. The seal of a non-siphon trap is shown at a in Fig. 48, and is the depth of water between the top arc of the inlet pipe, and the bottom arc of the outlet pipe. The full seal is "^ Fig. 46 Siphonage by Aspiration Digitized by Microsoft® Principles and Practice of Plumbing 91 Fig. 47 Effect of Siphonic Action on Non-Sipbon Trap Non-Siphon Traps is not more shown here, although after being subjected to siphonic action, the seal would not be over perhaps % inch. Effect of Back Pressure on Non-Siphon Trap. — The most common form of a non-siphon trap is a drum trap. In this form of trap the area of the body usually is four times the area of the waste pipe, so that to force the seal by back pressure, sufficient pressure is required to sustain a column of water b, Fig. 49, five times the depth of seal a. The depth of seal generally is 4 inches, hence to force the seal by back pressure, a pressure sufficient to sustain a column of water 20 inches high is required. This col- umn of water is equal to a pressure of .728 pound per square inch. Evaporation from rapid than from an equal size siphon trap, and calculated by the constant of evaporation, .4 of an inch per week, it would take, under ordinary conditions, fifty weeks for a 3-inch body drum trap with 4-inch seal and 1 1/2-inch waste pipe to lose its seal. Self-Scouring Action of Traps. — The chief objection to non-siphon traps heretofore has been that owing to their enlarged bodies they were not self- cleaning, hence they afforded a fouling place for the deposit of sediment. This objection has to a certain extent been overcome as a result of the discovery that water introduced with a rotary motion to the enlarged chamber thereby scoured it. Grease Traps. — Grease traps are separators in which grease, fats and oils are separated from greasy waste water, the grease being retained in the trap while the water escapes to the drainage system. They are used in connection with kitchen, scullery or other sinks, into which large quantities of greasy water are emptied, to Fig. 48 Seal of Non-Siphon Trap Digitized by Microsoft® 92 Principles and Practice of Plumbing intercept the grease while in a fluid state and thus prevent its adhering to the waste pipes, where it would congeal and successive deposits in time choke the pipe. Conditions Governing Use of Grease Traps. — Grease traps should be used to intercept the grease from all kitchen sinks in cities that have installed systems of sewerage from which storm water is excluded. Under such conditions, the sewers are so small and so poorly flushed that great liability would exist of partial or complete stoppage from the grease if grease traps were omitted. When a city has installed a combined system of sewer and storm water drains, grease traps may be omitted if the kitchen sink is not over fifty feet from the street sewer and the main house drain runs through the cellar exposed to the heat of a fur- nace. However, when the sink is over fifty feet from the street sewer, or when the main house drain is buried in the earth, so grease would be likely to chill be- fore it reached the street sewer, grease traps should be used. Also they should in every case be used in all large institutions, boarding houses, hotels and bake shops or other buildings where large quant- ities of grease are liable to find their way into the drainage sys- tem. Location for Grease Traps. — A grease trap should be located as close as possible to the sink from which it receives the discharges. It should not be placed in the kitchen, however, on account of the offensive odors that would enter the room every time the trap was opened to remove the grease. In detached dwellings, grease traps usually are made of brick and placed outside the house. A better practice is to make the trap of iron and locate it in the cellar or basement, safe from frost and close to the source of gi-ease. Fig. 49 lOri'oct of Back Pressure on Non-Siphon Trap Digitized by Microsoft® Principles and Practice of Plumbing ,93 Size of Grease Traps. — Grease traps to be effective must have at least twice the capacity of the greatest quant- ity of greasy water likely to be discharged at one time into them. This is so that the entering water will be chilled and the grease congealed and rise to the surface of the water, thus being retained in the trap. If the grease traps are too small, part of the entering water will pass through the outlet into the drain before it is sufficiently cooled, car- rying with it whatever grease it holds in suspension, which will adhere to the pipes. In ordinary residences, a dishpan full of greasy water is the greatest quantity likely to be emptied at one time, and if the grease trap is made to hold at least twice that quantity, it will fulfill all requirements. In hotels, clubs and other large institutions where a great many people are fed, the. probable amount of greasy water liable to be discharged at one time must be estimat- ^ig gg ed, and the grease Grease Trap trap made with a capacity of twice that amount. Types of Grease Traps. — There are two types of grease traps in use: An ordinary trap with large inter- cepting chamber, as shown in Fig. 50, and a water jacket grease trap. Fig. 51, around which cold water circulates to chill the water in the trap. The water for this purpose is taken from the cold-water supply pipe, and must pass through the water jacket of the grease trap before being drawn from a faucet. When a water supply pipe is con- nected to a grease trap for this purpose, it should be con- tinued to some unimportant fixture, or else connected to the hot-water tank, as water that passes through a grease trap jacket absorbs heat from the water within the trap and becomes disagreeably warm for most domestic uses. Slip-Joints. — Joints in which one pipe or member Digitized by Microsoft® 94 Principles and Practice of Plumbing slips inside of another and the junction between the two is made tight with a gasket compressed by means of a screw thread or bolts, are known as slip-joints. Any joint in which the parts are not bound together, but one part may be slipped out of place, having nothing to overcome in doing so but the resistance of the grip of the compressed gasket, should be classed as a slip- joint no matter what its use. Slip joints are permissible and very convenient when used on the house side of a fixture trap. Under no condi- tion, however, should a slip- joint be permitted on the sewer side of a trap, particularly on the sewer side of a water closet trap. Indeed, a gasket joint of any kind should not be permitted on the sewer side of any trap, and a slip- joint, which is the least se- cure of all forms of gasket joints, is the most objectionable joint of them all. The rule can be laid down that under no condi- tion should a gasket joint of any kind be permitted on the sewer side of any trap. If a gasket is used, no further evidence need be looked for. The gasket alone stamps it as insanitary. Attention should be called here to the fact that water closets are set with a putty joint, gasket, or sometimes a slip joint, which is extremely bad practice. Distance of Back-Vent from Trap. — The distance the back-vent can be placed from a trap without danger of the trap being self -siphoned depends entirely on the fall to the waste pipe from the trap to the stack. If the fall is slight, the vent pipe can connect to the waste pipe further away from the trap than when the fall is great. The rule is : Connect the back-vent to the waste pipe at such a point that the vent opening will be above the level of the water Vig. -,i Water .Taokol Gvrase Trap Digitized by Microsoft® Principles and Practice of Plumbing 95 in the trap. There will then be no long unventilated leg to form a siphon. The application of this rule can be seen by referring back to Fig. 45, which shows two traps, one in solid lines, the other in dotted lines, each a different distance from the soil stack, yet each free from danger of self-siphonage be- cause neither waste pipe from the trap dips low enough before entering the stack to form the long leg of a siphon. Whether there would be danger of siphonage from other fixtures discharging into the stack at higher levels would depend on the relative size of the stack, and the greatest discharge of water that would enter it at the higher level, and would be within reasonable limits independent of the distance of the trap from the stack. Indeed, the pull on the water in a trap is greater the nearer the trap is to the stack. It would be perfectly safe to set a closet four to five feet from a stack, and a small fixture-trap six to seven feet from the stack. . Back-Venting Traps. — Siphon traps, unprotected from siphonage by vent pipes, offer no security whatsoever against the passage of drain air into a building; therefore, any system of plumbing .in which siphon traps are used should be properly vented or back-vented. A vent pipe not only protects the seal of a trap from siphonage, but also relieves the seal from back pressure and affords ventilation for the short length of waste pipe from the soil or waste stack to the fixture trap. This last consideration is of but small importance, however, because the air in branch waste pipes is changed each time the fixture it connects to is flushed. Furthermore, the air in the short lengths is kept fairly pure by diffusion with the air in the soil or waste stack. Vent Connections to Traps. — An old method of back-venting fixture traps was to connect the vent pipe to the crown of the trap, as at a, Fig. 52. A better practice, however, is to connect the vent pipe to the waste pipe a few inches away from the trap, as at b, but not far enough away so the waste pipe would form the long leg of a siphon. When a vent pipe is connected to the crown of a trap it increases Digitized by Microsoft® 96 Principles and Practice of Plumbing the rate of evaporation of water from the trap ; also, when much grease is emptied into a fixture the vent pipe, if con- nected to the crown, is liable to become entirely stopped up with the grease.* Example of Back- Venting. — An example of back- venting the fixture traps in an ordinary bath room is shown in Fig. 53. The chief conditions to be here noted are: (1) The height of the vent pipe where it enters the vent stack. It is kept above the outlet to the highest fixture in the group so that the vent pipe cannot be used as a waste pipe by any of the fixtures in case the waste pipe becomes ob- structed; (2) the vent pipe slopes from the vent stack toward the fix- ture traps to discharge into the waste pipes all water of condensation or any sewage that might back up in the vent pipes, should the waste pipe be obstructed; (3) the distance away away from the seal of traps at which the vent pipes connect to the waste pipes. It should be further observed that the vent to the water closet does not connect to the closet trap above the fioor, but to the lead bend below the floor, as a permanent and secure joint cannot be made to an earthen- ware closet trap, owing to the shrink- age of the floor joists which would break the vent horn of the closet. If the closet is either of the siphon- jet or the siphon-action type, no vent will be necessary, providing fixtures do not discharge into the soil stack at a higher level, because siphonic action is necessary to operate either type of closet, Fig. 52 Bnok- Veil toil Ti-!>|is •Inspector AV. J. Freaney, of SI. Paul, In an examination of vent pipes from fixture traps, found tbat out of twenty-three traps from Isltchen sinks, twelve wore completely obstructed with urease, ten partially obstructed, and only one perfectly clear. The latter, however, had been regularly inspected and cleaned. Digitized by Microsoft® Principles and Practice of Plumbing 97 and the after-wash from the flush cistern is depended upon to again seal the trap. Main-drain traps, leader traps, yard and area traps and stall drain traps do not require back-venting, because if they are emptied by siphonage their seals are soon replaced by drippings. Connecting Several Fixtures to One Trap. — When a number of wash basins are grouped together in a wash room of a factory, hotel, or other institution it is common practice to connect the waste pipes from all the basins to one trap. A better practice, however, is to trap each basin separately. When but one trap is used in an installation of this kind, it leaves untrapped a large stretch of pipe, which in time becomes foul and emits disagreeable odors, that are carried into the room by local currents of air cir- culating in through the pipe at one basin connection and out at another basin. Kitchen Sinks and Laundry Trays. — There are con- ditions under which the use of one trap for two or more fixtures is permissi- ble. In apartment buildings, where laundry trays ad- join the kitchen sink, and there is a possibility that for long periods of time the trays may not be used, it not only is permissible but perhaps better to connect the waste pipe from the trays to the house side of the sink trap below the water level. By this arrangement a permanent seal is assured the trays whether they are used or not. The waste pipes from the trays, however, should be offset above the water level in the trap so the waste pipe will not stand full of water. The waste pipe from the kitchen sink should never connect to a laundry-tray trap, as that would leave untrap- ped a greater stretch of pipe than when the conditions are Fig. 53 Example of Back-Venting Digitized by Microsoft® 98 Principles and Practice of Plumbing reversed ; besides, the untrapped pipe would soon foul from the greasy sink water passing through it, and local circula- tion would set up from the tub waste through the tray waste, carrying the odors into the kitchen. Clothes Washing Machines; — In these days of ma- chines and machine labor, no private laundry is complete without a power operated machine washer for the launder- ing of the household linen. Machines designed for this purpose may now be had which can be supplied with hot and cold water, and connected to the drainage system. These machines are made for motors which are electrically operated, or with motors which are operated with water supplied from the city water mains. When water power is to be used, however, there must be an available pressure at the motor of at least 30 pounds per square inch, with fair volume, or the motor will not operate satisfactorily. In addition to a washing machine, a gas-heated or electrically-heated mangle will be found a valuable fixture in the laundry of every good-sized home. On the mangle most of the household ironing can be done, outside of the more particular pieces which are best done by hand, and between the washing machine and the mangle, the hardest and heaviest of household work is done without an effort. Digitized by Microsoft® Principles and Practice of Plumbing 99 CHAPTER X BLOW-OFF TANKS AND REFRIGERATOR WASTES Blow-Off Tanks for Boilers Effect of Steam in Drainage Systems. — High press- ure steam boilers should never blow off or exhaust directly into a drainage system, but should first pass through a cool- ing tank that will condense the steam and cool the water to a moderate temperature. When live' steam is discharged directly into a drainage system the steam heats the water in traps, causing it to vaporize and emit a disagreeable odor within the building. Also, if the system is constructed of cast iron with lead calked joints the expansion and con- traction of the lines will work the lead calking out of the hubs and cause the joints to leak. Type of Blow-Off Tanks. — A blow-off tank and con- nections are shown in Fig. 54. Water enters the condens- ing tank from the boiler through the pipe a. When re- leased from pressure, some of the water instantly flashes into steam and es- capes to the atmos- phere through the vapor pipe, b. Hot water entering the tank causes cold water from the bot- tom of the tank to overflow through the pipe c, to the house sewer outside of the main drain trap. .An equalizing pipe, d, admits air to the overflow pipe and thus prevents the water being siphoned out of the tank. Where gravity discharge cannot be had, boilers may be allowed to blow off into a sump, and the water when it has Fig. 04 Blow-Off Tank Digitized by Microsoft® 100 Principles and Practice of Plumbing cooled pumped out with a submerged centrifugal pump of the vertical type, direct connected to a motor. A vent from the sump to the atmosphere should be provided. Size of Blow-Off Tanks. — A blow-oflf tank should be large enough to hold one gauge of water from the steam boiler. In blowing off a steam boiler, one gauge of water is the most that should be blown off at one time, and if the tank is large enough to hold that quantity it will be suffi- ciently large for all purposes. The size of tank required can be found by multiplying the length of the steam boiler in feet by the diameter in feet and mliltiplying the product by one-third (4 inches being considered the depth of one gauge of water) . This product will be the capacity in cubic feet of the tank required. Example — What capacity blow-off tank will be required for a steam boiler 18 feet long and 5 feet in diameter? Solution— 18 X 5 X % = 30 cubic feet, and 30 X 7.5 = 225 gallons capacity. Stock sizes of blow-off tanks can be found in Table XIX. TABLE XIX. Dimensions and Capacities of Blow-Off Tanks Capacity Capacity Length DiaiT). Approx- Feet Gallons in Feet Inches Weight 33 250 G 30 r,m 43 32.") S 30 li.=)0 ."iS ■too 10 30 .soo ri;i 47.-> s 3(1 son sn 600 10 ;!ti D.iO no 700 12 36 1100 133 1000 12 12 1400 166 1250 12 48 1700 When ordering blow-off tanks the order should be accompanied by a sketch showing the location and size of the several outlets. When several boilers are connected in battery one blow-off tank will suffice for all, provided sufficient time is allowed between blowing off the several boilers for the water in the tank to cool, or if provision is made for cool- ing the hot water with cold water coils. Digitized by Microsoft® Principles and Practice of Plumbing 101 RoofL/ne. Size of Tank Outlets. — Blow-off outlets to steam boilers are seldom over two inches in diameter, therefore the inlet to blow-off tanks need not be over 2 inches, iron- pipe size. The outlet, however, should be 2i/^ or 3 inches in diameter, so the water will enter the sewer at a slow velocity. The vapor pipe should be 2 inches in diam- eter, and if it extends over 100 feet should be 21/2 inches in diameter. Drips from high-press- ure plants do not require a condensing tank but may con- nect to an atmospheric steam trap discharging into the house sewer outside of the main drain trap. Blow-offs from low-press- ure boilers need not pass through either a condensing tank or a steam trap, but may discharge freely into the house sewer outside of the main drain trap, if there is one, or in the house sewer where there is no main drain trap. Refrigerator Wastes System of Piping. — In apartment houses, of the bet- ter class, refrigerator waste -L pipes are usually installed to carry off the drip from ice boxes in the several apart- ments. Fig. 55 shows the general system of piping for refrigerator wastes. The main refrigerator stack does not connect to the drainage system but discharges into a trap- Fig. 55 Refrigerator Waste Pipes Digitized by Microsoft® 102 Principles and Practice of Plumbing 56 Refrigerator Safe-Pan ped and water-supplied sink in the cellar or basement, and should open to the atmosphere above the roof. Galvanized wrought iron pipe should be used for refrigerator wastes, and the ends should be well reamed to remove the burr formed by cutting the pipe. Fittings should be of the recessed drainage type, well galvanized both inside and out. Full Y fittings should be used for branch connections to the various refrigerator safes, and a Y branch with clean-out plug should be used at all changes of direction of the horizontal mains. The main waste pipe from refrigerators should never be less than ll^ inches, diameter, , and seldom need be over 11/2 inches. Branch connections to the refrigerator safes, also refrige- rator wastes in pri- vate houses, need not be over 1 inch in diameter. Refrigerator Safes. — The manner of con- structing and lining refrigerator safes is shown in Fig. 56. Beveled supporting strips are nail- ed to the floor to form a shallow pan, about IV2 inches deep, which should be made water-tight by lining with sheet lead or sheet copper. The outlet from the pan should be countersunk, and the opening protected by a removable strainer secured in place by a cross bar. Brass, aluminum, galvanized cast-iron refrig- erator safes, also earthenware safes with couplings, can now be had. Any of these materials is better than lead safe pans. Trapping Refrigerator Safes. — Each refrigerator safe should be separately and properly trapped and con- nected to the main refrigerator waste stack. The best type of trap to use for this purpose is a plain siphon trap of % S pattern. The angle of the outlet leg of a % S trap permits the slime that accumulates in the waste pipe from an ice Digitized by Microsoft® Principles and Practice of Plumbing 103 box to slide into the vertical stack and thence to the sink. It is not necessary to back-vent refrigerator waste traps, nor use non-siphon traps, because a flush of water of suffi- cient volume to siphon a trap is never discharged into a refrigerator waste ; even if it were, the constant drip from the ice box would soon seal the trap again. In private houses the refrigerator waste need only ex- tend from the refrigerator safe to the drip sink, where it should terminate with a light swing-check valve to prevent cellar air entering the living rooms through the waste pipe. No trap is required where only one refrigerator connects to a waste, nor is it necessary in such cases to extend the pipe through the roof. Digitized by Microsoft® 104 Principles and Practice of Plumbing CHAPTER XI MECHANICAL DISCHARGE SYSTEMS Sub-Sewer Systems. — Mechanical ejectment of sew- age is resorted to in cases where the street sewer is above the level of the area to be drained. This condition, how- ever, is only found in the sub-basement floors of tall city buildings, underground public toilet rooms and underground passenger stations. A system of mechanical ejectment consists of a gravity drainage system to a receiving tank or sump located in a water-tight pit at the lowest part of the drainage system, and a pump or compressed air ejector to raise the sewage and discharge it into the street sewer. Systems of piping for sub-sewer drainage are the same as for gravity discharge systems. In cities where main drain traps are required, the sub-sewer system should have a main drain trap and fresh air inlet, and the fixture stacks should extend through the roof. In short, a sub-sewer system is exactly the same as a gravity system, except the mechanical apparatus for elevating the sewage. A separate vent pipe should extend from the tank or sump to above the roof. Centrifugal Pump Ejectors. — There are three types of apparatus used to raise sewage to the street sewer, each of which has certain features to recommend it. When the volume of the sewage to be removed is large and the height to be raised is small, a centrifugal pump will give very satisfactory results. This type of pump can be driven by belting or may be operated by an electric motor direct-con- nected to the pump shaft. By means of a float and an auto- matic switch an electric-driven pump can be made to operate automatically, starting when the tank is filled with sewage and stopping when it is empty. The manner of installing a centrifugal pump and tank is shown in Fig. 57. With this type of ejector an ordinary steel tank is used that may be either open or closed. The pump should be set below the level of the receiving tank, so it will remain full of water Digitized by Microsoft® Principles and Practice of Plumbing 105 and not require priming. If placed above the level of the tank a primer will be necessary to start the pump, and this so complicates the apparatus that it is more difficult to fit up to work automatically. Where the sewage is coarse and full of solid matter, as is likely to be the case in slaughter houses or factories, a centrifugal pump will give the best results. It has few working parts to get out of order, and no parts that can choke up and thus render the pump tem- porarily useless ; for any substance, even coal or bricks, that passes through the inlet port can easily be discharged from C'L'iitrihigal Pump Sowage Lift the outlet. Speed is an important factor in the capacity of centrifugal pumps; increasing the speed increases the capacity and also the height to which it will raise sewage, while decreasing the speed will reduce considerably the volume of sewage and the height it will be raised. Direct- connected, electrically-operated, vertical type of submerged centrifugal pumps are best for the purpose. The operation of the apparatus shown in Fig. 57 is as follows: Sewage enters the sump a through the house drain b; as the tank, fills, the sewage raises the float c, and thus by means of the chain, pulleys and weight w, depresses Digitized by Microsoft® 106 Principles and Practice of Plumbing the lever d until it reaches a certain point when contact is made that completes an electric circuit connected to the electric motor e. The current thus automatically turned on operates the electric motor that drives the pump p, and thus ejects the sewage from the tank through the discharge pipe to the sewer s. As the water line in the tank lowers, the float falls until it reaches a certain level near the bottom, when the automatic switch opens, thus breaking the electric circuit and stopping the pump. Piston-Pump Ejectors. — When the volume of sewage to be raised is small or the height it is to be elevated is great, the piston type of pump will give the best results: The sewage should be screened, however, before entering the suction pipe of this type of pump, to prevent the en- trance of anything that might have been carelessly intro- duced into the drainage system which might interfere with or injure the working parts of the pump. Piston pumps are suitable only for comparatively clear sewage, and should not be used where coarse, insoluble materials are discharged into the drain or where chemicals are discharged that might cut the valve seats of a pump. Piston pumps may be electrically driven or operated by steam, and may be made to operate automatically or to be started and stopped by an attendant. The manner of installing a piston pump ejector is similar to the manner of installing a centrifugal pump ejector, with the single exception that a piston pump may be located at any conveni- ent point not over twenty-eight feet above the level of the sump. When steam is the motive power, the pump may be connected up to work automatically in the same manner as a feed-water pump and receiver. CoMPRESSED-AiR EJECTORS. — Air ejectors are now more generally used for sewage ejectment than any other type of apparatus. They are automatic and almost noise- less in operation, are perfectly odorless, and have but few working parts than can get out of order. A type of com- pressed air ejector known as the Shone, is illustrated in Fig. 58. Sewage flows into the chamber a through the house drain b. As the chamber fills with sewage it raises Digitized by Microsoft® Principles and Practice of Plumbing 107 the bucket c until it reaches a certain level, when by means of the rod d, it opens valve e, thus admitting compressed air to chamber a. The pressure of air closes the check valve / through which sewage entered the chamber and opens check valve g through which it forces the contents of the sump into the street sewer. As the sewage level in the sump falls, the bucket float, which remains full of sewage, lowers with the contents until it reaches a point near the bottom of the chamber, when it closes the air valve, thus Fig. 58 (•(iminisscil Air Sewage Ejector shutting off the supply of compressed air, and at the same time opening a vent through which the confined air can escape to a vent stack. Valve h is placed in the house drain pipe to the tank, and valve i in the discharge pipe from the tank, so that the ejector may be cut out of service at any time. Sewage ejectment apparatus should always be installed in duplicate so that either apparatus may be cut out for Digitized by Microsoft® 108 Principles and Practice of Plumbing cleaning or repairs without interrupting the drainage service. The manner of installing a duplicate compressed air apparatus is shown in Fig. 59. The size of sump tanks for sewage ejectment depends upon the frequency with which they are to be emptied and the probable amount of sewage to be taken- care o.f . When operated automatically they need only be large enough to hold an hour's storage of sewage, during the hour of maxi- mum flow. The process of emptying occupies only a few minutes, when the tank is ready for service again. If the apparatus is not to be operated automatically, storage Sosement Ceiling SystPm Fig. .Vi Iff Siib-Sewei' Mfcbanical i">ischarge capacity for twenty-four hours should be provided. In esti- mating the quantity of sewage from basement floors of different classes of buildings, greater per capita allowance should be made for the basement and sub-basement floors of hotels and like institutions than from other classes of buildings. Storage tanks for compressed air are usually made of galvanized sheet iron similar to those used for the storage of hot water. They should be equal in size to the cubical capacity of the sumps they are to discharge. When made of such a size, at least two pounds pressure of air should Digitized by Microsoft® Principles and Practice of Plumbing 109 be maintained as working pressure for each foot in height the sewage must be raised; with greater pressure a more speedy ejectment is obtained. To operate satisfactorily with lifts of less than 7 feet, at least 15 pounds pressure of air should be maintained; 30 to 40 pounds is the pressure the average sewage ejectment plant operates under. Sub-Soil Drainage Object of Sub-Soil Drainage. — In localities where the ground water is high or where impervious strata of clay or rock causes seepage to dampen the foundation walls or wet the cellar floor, sub-soil drains are resorted to. The manner of laying a sub-soil drain is shown in Fig 60. A line of field tile is laid around the out- side of the founda- tion wall below the level of the founda- tion footings or the cellar floor. The pipes are laid with open joints which are covered with tile collars, pieces of tar paper, ex- celsior, bagging or some other coarse material that will keep out dirt until the earth settles and packs into shape. The drain should be covered for a depth of 12 to 18 inches with crushed stone and the trench then filled to within a foot of the top with loose porous materials through which water will easily percolate to the drain. The top dressing for the trench may be any kind of good loamy soil suitable for a lawn. Disposal of Sub-Soil Water. — When the street sewer is provided with a sub-sewer drain, as is usually the case in localities where the ground water is high, the proper place to dispose of sub-soil water is in the sub-sewer drain. M^st Fig. 60 Sub-Soil Drain Digitized by Microsoft® 110 Principles and Practice of Plumbing brick sewers, Fig. 61, are provided with a tile invert, a, the channels of which serve as a sub-sewer drain; and pipe sewers in wet districts usually have a field pipe sub-sewer drain. When, however, there is no sub-sewer drain the sub-soil water can discharge into the house sewer through a water seal and tide water trap. Sometimes a sub-soil drain is so far below the sewer level that sub-soil water cannot discharge into it by gravity. When such is the case, it can be gathered in a sump and discharged to the street sewer by a submerged type centrifugal pump. If, however, the volume of water is too small, and the distance it is to be raised too short to warrant installing a sewage ejectment apparatus, an automatic cellar " ^ ^o p drainer, may be used. This type of apparatus may be operated by water or steam, although city water is generally used. It can- not be operated by air pressure. It operates on the principle of an ejector. The drainer is placed in a pit below the level of the cellar floor, into which the sub-soil water drains. When the water reaches a rig 61 certain level it raises the float ; this turns city water on to the appara- tus, and as the water flows through the ejector nozzle, it entrains water from the pit which mixes with the city water in the pipe, and together they are discharged into a water- supplied sink at some convenient point. When the water is discharged from the pit the float falls again, thus shutting off the flow of the city water until the pit fills again. This method, however, is too expensive to use for discharging large quantities of water and is not economically effective for a greater lift than 12 feet. The height to which water can be raised by a cellar drainer depends upon the available water pressure; with a pressure of 100 pounds, water can be raised 25 feet, but the amount of city water required to raise water that height makes the method too expensive for handling large quantities of water. At least four pounds Digitized by Microsoft® Principles and Practice of Plumbing 111 of pressure are required for each foot of lift, with a mini- mum pressure of at least 10 pounds. The possibility of using water from automatic cellar drainers for flushing fixtures should not be overlooked. Ordinarily, the water discharged by a water drainer is per- fectly clear, being nothing more or less than the ordinary ground water of the locality. To this must be added the city water used for operating the drainer, which, of course, is also clear and suitable for flushing purposes. Where there are basement closets or urinals to be flushed, or water can be used on an overshot water wheel for operating mechanical apparatus, as is done with some domestic ice-making machines, the drainage water can be used for this purpose, thereby making the operation of the drainer free of cost. The lower the lift of the drainage water, the less water will be required for the purpose, so, instead of a water supplied sink, ordinarily the water can be discharged into a floor drain, or yard drain if the climate is not too cold. An automatic cellar drainer, or a mechanical discharge system of any kind, ought never to be used, of course, when it is possible to take care of the drainage water by gravity. It is only when the surface to be drained is below the level of the street sewer or other place of sewage disposal or drain- age water disposal, that they are permissible. It is not advisable to connect an automatic cellar drainer direct to a drainage system, for, besides the possi- bility of sewer air finding its way into the house through the connection during dry weather, there is the additional possi- bility of water running continuously to waste through the cellar drainer should it get out of order without any one being aware of the fact. Both sanitary and economic rea- sons, therefore, require that a cellar drainer discharge into a tank, sink, floor drain, or other receptacle where the water can be seen running when the apparatus is in operation. Drainers will work satisfactorily with 4 pounds press- ure to one foot in lift. To raise water : Digitized by Microsoft® 112 Principles and Practice of Plumbing 1 foot requires 4 to 5 lbs. pressure 2 " " 8 " 10 " 3 " " 12 " 15 " 4 " " 16 " 20 " 5 " " 20 " 25 " and so on in proportion up to 12 feet in height. Drainers do not satisfactorily lift water more than 12 feet. Digitized by Microsoft® Principles and Practice of Plumbing 113 PART n WATER SUPPLY SYSTEMS COLD WATER SUPPLY CHAPTER XII PROPERTIES OF WATER General Data About Water. — Pure water is a color- less, tasteless, odorless, limpid fluid, that is practically incompressible; for each atmosphere of pressure it sus- tains it is compressed only 47 V2 millionths of its bulk. Its compressibility is from .000040 to .000051 fbr one atmos- phere, decreasing- with increasing temperature. For each foot of pressure, distilled water will be diminished in volume .0000015 to .0000013 of its bulk. Water is so nearly incom- pressible that even at a depth of a mile a cubic foot of water will weigh only about half a pound more than at the surface. It is a chemical combination of oxygen and hydrogen in the proportions of 88.9 parts by weight of oxygen to 11.1 parts of hydrogen, or 1 volume of oxygen to 2 volumes of hydro- gen. Its weight varies with its temperature; at 62° F., which is taken as the average temperature, 1 cubic foot weighs 62.355 pounds. For ordinary calculations, the weight is taken in round numbers at 62.5 pounds per cubic foot: when greater pre- cision is required, it is taken at 62.4 pounds per cubic foot, its weight at 52.3° F. The gallon is the unit of measure for water. One gal- lon of water measures .134 cubic feet, contains 231 cubic inches, and at 62° F. weighs about 8% pounds. The United States gallon differs from the British or Imperial gallon, with which it should not be confused. A comparison of the American and Imperial gallon may be found in Table XX. Digitized by Microsoft® 114 Principles and Practice of Plumbing TABLE XX. Weight and Capacity of Different Standard Gallons of Water Imperial or English. United States New York 10 * ^g « '■■^ fll3 = B •"1 ^•- ro lOl^ ^ CO !« M^ P III II 277.274 10.00 6,232102 231 8.33448 7,480519 221.8171& 8.00 7.901285 70,465 58,327 58,538 « °.S 9 2 0^5 62.321 62.321 62.321 Notable Temperature of Water. notable temperatures for water, viz. : -There are four Fahr. Cent. 32° or 0° =^ the freezing point under one atmosphere; 39.1° or 4° =: the point of maximum density; 62° or 16.66° =: the British standard temperature; 212° or 100° := the boiling point under one atmosphere. The weight of one cubic foot of water at the four notable temperatures may be found in Table XXI. TABLE XXL Weight of Water At 32° F 62.418 pounds At 39 . 1° 62 . 425 pounds At 62° (standard temperature) 62 . 355 pounds At 212° 59.640 pounds The following factors are useful for changing given quantities of water from one denomination to another : 1 cubic inch of water weighs .577 ounce or .03608 pound. ] cubic foot contains 1,728 cubic inches. 1 cubic foot conlains 7.485 United States gallons, which, in ordinary calcula- tions, is taken as 7.5 gallons. Cubic feet X 62.5 = pounds Pounds '.'.'.'.'.'.-^ 62.5 = cubic feet Gallons X 8.3 = pounds Pounds ^ 8.3 _ gallons '■"bic feel X 7.5 = gallons •"■allons -^ 7.5 = cubic fed Digitized by Microsoft® Principles and Practice of Plumbing llS Snow and Ice. — Water expands in freezing about one- twelfth of its bulk, or from 1000 to 1083. Sea water freezes at 27° F. The ice is fresh. Specific gravity of ice, 0.916 Ure. Specific gravity of ice, 0.918 Miller. Specific gravity of ice, 0.9184 Abel & Bloxani. 1595 cubic inches of water will expand in freezing to one cubic foot of ice. One pound of ice at 32° F. has a volume of .0174 cubic foot, 30,067 cubic inches. Lbs. One cubic foot of ice weighs 57.135 Ure. One cubic foot of ice weighs 57.260 Miller. One cubic foot of ice weighs 58.632 Abel & Bloxam. Relative volume of ice to water at 32° F., 1.0855. At high pressure the melting point of ice is lower than 32°, being at the rate of .0133° for each additional atmospheric pressure. The specific heat of ice is .504, that of water at standard temperature being 1. Sound ice, two inches thick, will bear the weight of the average man; four inches, a man on horseback; six inches, cattle and teams with light loads ; eight inches, teams with heavy loads; ten inches, will sustain a pressure of 1000 pounds per square foot. The ice must be sound, free from shakes, cracks and frozen snow. Snow is 10 to 12 times lighter than an equal volume of water ; that is, one inch of rainfall will make from 10 to 12 inches of good, clear, crystalline snow. A cubic foot of fresh snow, according to the humidity of the atmosphere, will weigh from five to twelve pounds. A cubic foot of snow moistened and compacted will weigh fifteen to fifty pounds. Molesworth gives the following relating to snow : Specific gravity is 0.0833 One cubic inch of snow, = 0.003 pound. One cubic foot of snow, r= 5.2 pound. One pound of snow, =: 332.6 cubic inches. One pound of snow, = 0.1923 cubic foot. One inch snow fall, = 0.433 lbs. per sq. ft. Digitized by Microsoft® 116 Principles and Practice of Plumbing Water in freezing always expands. If it is so confined that expansion is impossible, it remains liquid even at tem- peratures far below the freezing point; but the instant pressure is removed, the water crystallizes into solid ice. As there is a constant effort on the part of the water to form ice and as a considerable pressure is needed to counter- balance its expansive power, the lower the temperature the greater this pressure becomes. At a temperature of 30 degrees Fahrenheit, just two degrees below the freezing point, the pressure is equal to 138 tons per square foot. It will be seen, then, that when water freezes in a pipe or closed vessel, it exerts a pressure of approximately one ton per square inch; and this is the destructive agency which bursts pipe and tanks. Classification of Water. — Waters for domestic uses may be divided into two general classes; hard waters and soft waters. Hard waters can be either permanently hard, temporarily hard, or both permanently and temporarily hard. By hardness of water is meant its soap destroying or neutralizing power, which is due to the presence of car- bonates or sulphates of lime or magnesia. A large degree of permanent hardness indicates a bad water. Perma- nently hard waters contain sulphates of lime or magnesia in solution; temporarily hard waters contain carbonates of lime or magnesia in solution, and both permanently and temporarily hard waters contain sulphates and carbonates of lime or magnesia in solution. Hardness of water is measured in degrees (Clark- Wanklyn), and each degree of hardness corresponds to one grain of carbonate of lime or magnesia to one English gallon of water. Hardness expressed in parts per 100,000 can be converted to Clark's scale by multiplying the hard- ness by .7. The reason for this is Clark's scale gives the results in grains per English gallon, and there are 70,000 grains in an English or imperial gallon. Example— How many degrees hardness (Clark) in water that is 20 parts hard per 100,000? Solution— .7 X 20 = 14 degrees Clark.— Ans. Digitized by Microsoft® Principles and Practice of Plumbing 117 Conversely, hardness expressed in degrees (Clark) can be changed to parts per 100,000 by dividing the degrees of hardness by .7. Example — How many parts of hardness per 100,000 in water that contains 14 degrees of hardness? Solution— 14 ^ .7 = 20 parts per 100,000.— Ans. Hardness expressed in parts per 100,000 can be changed to grains per United States gallon by multiplying the hard- ness by .584. The reason for this is that a United States gallon contains approximately 58,400 grains. Conversely, hardness expressed in grains per United States gallon can be changed to parts per 100,000 by dividing the grains of hardness by .584, or, where great refinement of calculation is not required, by the constant .6. Example — How many grains of hardness per United States gallon in water that contains 20 parts per 100,000? Solution — 20 X .584 = 11.68 grains per gallon. — Ans. Example — How many parts of hardness per 100,000 in water that contains 11.68 grains per United States gallon? Solution— 11.68 -=- .584 = 20 parts per 100,000.— Ans. The manner of determining the degree of hardness in water is as follows: Seventy cubic centimeters* of water are placed in a clean glass bottle large enough to hold two or three times that quantity. A clear solution of soap of standard strength is then added, a little at a time, from a ' graduated tube, and the mixture briskly shaken. On some water.s a slight lather will form at first, which will quickly disappear, or if the water is very hard a curd will form. More soap should then be added, shaking the bottle after each addition until the lather formed is sufficiently perma- nent to stand for five minutes. The number of cubic centi- meters of soap solution added, less one, indicates the hard- ness of the water in degrees. The one cubic centimeter is deducted because even distilled water requires a small quan- tity of soap to make it lather. Standard Soap Solution. — Standard soap solution is of such strength that one cubic centimeter contains sufficient -Tiible for cfpiiverlinK Ameriran antl metric measures in appendix. , Digitized by Microsoft® 118 Privciples and Practice of Plumbing soap to exactly neutralize one millogram of dissolved car- bonate of lime. It is made by mixing half an ounce of finely shredded castile, or mottled soap, with two pints of methyl- ated spirits and one pint of distilled water. The mixture should be kept at ordinary temperature, and allowed to stand for a few hours, occasionally shaking, then passed through a filter of blotting paper. Before using the solu- tion it should be tested by means of water of known hard- ness. In case the solution is too strong, it should be diluted with spirits and water until the strength is just right. Soft water contains no mineral impurities. Rain water is the purest kind of natural soft water. The character of water, its corresponding degree of hardness and chemical substance causing the hardness, rated as equivalent to grains carbonate of lime, may be found in Table XXII. TABLE XXII. Hardness of Waters Chariiclcr of tlio Water "a B O >> S ■g-'a oSS^ SO 3" g a j 20 flo S'"'S 1"^ 05 0. .Sol' 1° 1.4 1 2° 2.8 2 3° 4.3 3 6° 8.6 6 8° 11.4 8 9° 13. 9 12° 17 12 16° 23. 16 17° 24. 17 c3 QJ*- Ogco .5 o'aS Very soft Soft Softness decreasing Moderately soft Moderately hard Hard \'ery hard Excessively hard Intolerably hard above this point -.82 1.05 2..'il ~^. 6.6.') 7.6 9.9 13.4 14. Even the softest of water contains a small proportion of lime or magnesia as a rule, and it may be assumed that the softest of water is at least one degree hard. In limestone regions, such as the upper Mississippi Valley, water of 10 degrees hardness is not uncommon, while some Of the water pumped from the chalk beneath the City of London, England, is as hard as 22 degrees Clark. Digitized by Microsoft® Principles and Practice of Plumbing lid CHAPTER XIII SOLVENT POWER OF WATER Range of Solvency. — Water is an almost universal solvent. Its range is greater than any other known liquid. It dissolves to a greater or less extent all minerals, and many metals with which it is brought in contact. As a rule, the solvent power of water increases with its temper- ature, but for common salts the solvent power is nearly con- stant at all temperatures. Lime salts are more soluble in cold than in hot waters, and it is diie to this latter fact that incrustation of water backs takes place in regions when the water supply is hard. In percolating through the earth the water dissolves carbonates or sulphates of lime or mag- nesia from lime rocks, until the water reaches the point of saturation; then, when subjected to heat in a water back or heater, the point of saturation of the water is lowered, thus liberating some of the lime or magnesia which settles upon and becomes baked to the walls of the water back or heater. The proportion of mineral that can be dissolved by a given quantity of water depends upon the nature of the mineral, the kind of water and its temperature. The rela- tion between soluble minerals and water is absolute. That is, at a given temperature a certain quantity of water will dissolve a definite quantity of mineral salts; if a quantity greater than this be added to the water, the amount in excess will settle to the bottom of the vessel. The water is then saturated, and the mixture is a saturated solution. By increasing or decreasing the temperature of the water, as the nature of the mineral requires, a greater quantity can be dissolved. The greatest quantity of various substances in common use that can be dissolved by one imperial gallon of water can be found in Table XXIII. The figures do not indicate Digitized by Microsoft® 120 Principles and Practice of Plumbing the weight of chemical contained in a goUon of saturated solution. Effect of Waters Upon Metals. — The solvent power of water is not confined to minerals alone, but, under favor- able conditions, will attack and dissolve metal from water pipes or from other metallic surfaces with which it comes in contact. The energy with which water attacks metals TABLE XXIII. Solubility of Water (COLLETT) One Imperial GaUon of Pure Water can Dissolve of Substance At 60 Degrees Fahrenheit At 212 Degrees Fahrenheit Alum (potash alum) Aluminum sulphate Ammonium oxalate Barium chloride Barium hydrate *Calcium carbonate Calcium chloride Calcivim Calciimi nitrate Calcium oxide (lime) fCaleium sulphate Ferrous sulphate *Magnesiimi carbonate IMagnesium chloride Magnesium hydrate Magnesium oxide Magnesium sulphate Sodium biborate (borax) . . . . Sodium carbonate (di'y) . . . . Sodium carbonate (crystals) Sodium chloride Sodium hydrate Sodium hyposulpMte Sodium phosphate Sodium sulphite Sodium sulphate 0.95poimds 3.3 pounds 0.45 pounds 3.5 pounds pounds grains poimds grains pounds grains grains pounds Doubtful 20.0 pounds grains grsdns pounds pounds pounds pounds pounds pounds pounds pounds pounds pounds 0.5 2.5 40.0 93.0 40.0 70.0 161.0 2.0 2.0 1.4 3.0 0.4 1.2 4.1 3.5 6.1 5.0 1.2 2.5 1.1 35.7 pounds 8.9 pounds 4.08 pounds 6.0 pounds 1.0 pounds 1.5 grains Unlimited 53.6 grains Unlimited 40.5 grains 152.0 grains 17 . 8 pounds 1.5 grains 40.0 pounds 2.0 grains 1.4 grains 13.0 pounds 5.5 pounds 4.5 pounds 14.0 pounds 4.0 pounds Unlimited 20.0 pounds 10.0 pounds 4.2 pounds •Insoluble at about 290 degrees Pahrenlielt. tDecomposes at boiler temper- ature in presence of alkaline earths or iron, tlnsoluble at 302 degrees Fahren- heit, equal to 70 lbs. steam pressure. depends largely upon the character of the water, the nature of the metal and the amount of free carbonic acid contained in the water. As a rule, soft water attacks and dissolves metals to a greater extent than will hard water, although there are exceptional cases where permanently hard waters Digitized by Microsoft® Principles and Practice of Plumbing 121 have been known to attack lead pipes with an energy equal to that of soft waters. It is not sufficient that water be soft to cause it to attack metals ; there must also be present in the water some oxygen and carbonic acid, either free or in solution. If either the oxygen or the carbonic acid are TABLE XXIV. Lead Found in Drinking Water I.IST or CITIES AND TOWNS WITH MAXIMUM AMOUNTS OF I,EAD FOUND IN SAMPLES OF WATER TAKEN DURING ORDINARY USB AND AFTER STANDING IN THE PIPE LOCALITY Lead Parts per 100,000 (.05 parts of lead per 100,000, dangerous) During Ordinary Use After Standing in Pipe .0029 0.0043 .0171 0.0571 .1714 0.1371 .0257 0.0314 .0086 0.0171 .0114 0.0286 .0086 0.0114 .0086 0.0086 .0100 0.0200 .0286 0.1143 .0229 0.0457 .0457 0.4571 .0200 0.0457 .0371 0.1829 .0800 0.4000 .5143 0.4643 .0086 0.0143 .0400 0.1371 .3429 1.1429 .0171 0.0429 .0714 0.1714 .0071 0.0329 .0043 0.1371 .0200 0.0571 .0152 0.0314 .0800 0.2286 .0229 0.0343 Amesbuiy Andover Attleborough Beverly Bridgewater Brooklme Cambridge Cohasset Dedham Franklin Grafton Hyde Park (old wells) Hyde Park (new wells) Lawrence Lowell (bonlvevard wells) Lowell (cook and hydraulic wells) Marblehead Metropolitan supply Middleborough Needham Newton North Attleborough Norwood Webster WeUesley Weymouth Wobum (Report Massaclnisi'tts Bonrd of Health, 1900, page 400.) lacking, the solvent power of the water will be greatly reduced. Effect of Water Upon Lead. — Water containing a fixed amount of oxygen and a varying amount of carbonic Digitized by Microsoft® 122 Principles and Practice of Plumbing acid acts upon lead with an energy proportional to the amount of carbonic acid present. The action of water upon a bright lead surface is much more energetic than upon a dull lead surface. Thus, city rain water, stored for 3V^ months in contact with new and old lead surfaces, was TABLE XXV. Lead in Samples of Ground Waters AKBANOEU ACCORDING TO AVEBAGE AMOUNT OF lEAD FOUND WHEN WATER IS IN OBDINABY USE (PARTS PER 100,000— .(» PART PER 100,000, DANGEROUS.) LOCALITY Lowell (cook & hyd. wells) Middleborough Attleborough Newton Avde Park (old) Wells) Lowell (boulevard wells) Grafton Hyde Park (new wells) Wellesley Webster Needliam Dcdham Bi'oolvline Bridgewatcr. . . . North Attle- borough Cohasset SAMPLES TAKEN In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary iise After standing in pipe In ordinary use After standing in pipe In ordinary use After standing in pipe . In ordinary use After standing in pipe. , In ordinary use After standing in pipe . In ordinary use After standing in pipe . In ordinary use After standing in pipe . In ordinary use After standing in pipe . In ordinary use After standing in pipe . In ordinary use After standing in pipe . In ordinary use After standmg in pipe , In ordinary use After standing pipe . . . . In ordinary use After standing in pipe In ordinary use After standing in pipe , OS > .1608 .2535 .1549 .6171 .0697 .0905 .0432 .0908 .0400 .3029 .0202 .0861 .0187 .0329 .0172 .0329 .0101 .0219 .0100 .0286 .0091 .0269 .0082 .0150 0074 .0197 .0057 .0143 .0049 .0226 .0048 .0043 as 79 123 95 179 43 62 265 32. 98 76 112 1230 1 461 127 144 30 ■""Jo H 1 Vs 3 .' feO 3.287 4.148 3.242 1.187 3.243 1.301 1.912 2.733 1.092 1.689 392 1.611 1.119 1.084 1.529 2.411 W 3.5 2.6 1.7 2.2 4.(i 1.:. 3.2 2.9 2 3 0.8 2.1 4.1 4.7 -2.6 2.9 6.3 (Roport ;\lassii(lnisoHs Slate Hoard nf Ilo.iltli, 1900, page 491.) Digitized by Microsoft® Principles and Practice of Plumbing 123 found to contain in suspension and solution the following amount of lead: * Stored in old lead, Stored in new lead. 3.65 parts per million 58.10 parts per million The importance of this will be realized when it is known that 0.5 part of lead per million is considered by most authorities the danger limit. At Lowell, Mass.f, the water from a well that caused a serious outbreak of lead poisoning was found, upon analysis, to be heavily charged with carbonic acid and to contain 2.30 parts of lead per million. Hard waters generally protect lead pipe by depositing on the inner surface an insoluble coating. As a rule, the TABLE XXVL Lead in Samples of Surface Waters ARRANGED ACCORDING TO AVBKAGE AMOUNT OF I.EAD FOUND WHEN WATER IS IN ORDINARY USE (PARTS PEE 100,000— .05 PART PER 100,000, DANGEROUS.) LOCALITY SAMPLES TAKEN Lead (Aver- age) Aver- age Length of Pipe (Feet) Aver- age Size of Pipe (Ins.) Free C.0.2 Hard- Lawrence. . . Weymouth . Metropolitan supply Andover Beverly. . . Cambridge. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. .0543 .0704 .0314 .1167 .0111 ,0293 .0108 0257 0087 0147 0025 0064 ,104 .109 85 122 84 58 H M 1.100 0.152 1.105 0.119 0.121 1.225 1.6 0.3 1.3 1.0 2.3 2.7 (Report Massacbusetts State Board of Health, 1900, page 491.) harder the water, as compared with the free carbonic acid, the less effect the water has upon the lead. Ground water is generally more energetic than surface water in its action upon lead, although surface water is more liable to become contaminated with sewage, in which case the resultant •Mason Water Supply, page 398. tMassachusetts State Board of Health Report, 1900, page 488. Digitized by Microsoft® 124 Principles and Practice of Plumbing carbonic acid would make it more dangerous than ground water. An idea of the amount of lead dissolved from lead pipes by different kinds of water can be found in Tables XXIV, XXV, XXVI. In these tables the quantity of lead dis- solved is stated in parts per 100,000 in which amounts .05 part of lead is considered the danger limit. TABLE XXVII. Zinc in Samples of Ground Water (PARTS PEE 100,000.) LOCALITY West Berlin Millbury Newton Marblehead Grafton Lowell (cook and hyd. wells)., . Weliesley Fairhaven Lowell (boulevard wells) Webster Reading Warren SAMPLES TAKEN In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. Inordinary use After standing in pipe . In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. In ordinary use After standing in pipe. Zinc (Average) 1.8469 .3084 .7931 .1254 .5551 .0857 .4914 .0733 .3257 .'•2867 .0686 .2257 .0527 .6686 .0338 .1522 .0286 .3628 .0000 .0000 .0000 .0000 Average Length of Pipe (Feet) ^ Galv. Iron 4,000 53 74 65 117 Brass 40 60 90 [ Galv. Iron 100 40 [ Galv. Iron Cistern Average Size of Pipe (Inches) H H W% \:, (Itcjiurl, Massacliu.scll.^ Sliilc Iloai-d ,,f nc-iilth, 1900, page 490.) These tables all show the increased amount of lead dis- solved from pipes by water that was standing for some time, and indicate the additional protection to health that can be obtained by allowing the water in the service pipe to run to waste before drawing any for cooking or drinking purposes. Effect of Galvanized Pipe Upon Water.— Zinc coat- ings on the surface of galvanized iron pipe are attacked and dissolved by some waters almost as energetically as is lead Digitized by Microsoft® Principles and Practice of Plumbing 125 pipe. Zinc is also dissolved to a considerable extent from brass pipes. At Cwmfelin,* galvanized iron pipe that con- ducts water from a spring to the town, a distance of one- half mile, was found to change the character of the water as shown by the following analysis : At Spring At Delivery Free ammonia none 114, Nitrogen as nitrates 8 none Total residue 154.3 270 Zinc carbonate none 91.6 TABLE XXVm. Zinc in Samples of Surface Water (PAKTS PER 100,000.) Average Average LOCALITY SAMPLES TAKEN Length of Size of Pipe Pipe (Feet) (Inches) Sheffield f In ordinary use After standing in pipe. . .8667 \ Galv. Iron 1 246 M Palmer ^ In ordinary use After standing in pipe. . .2900 .4280 I Beverly | In ordinary use After standing in pipe. . .2714 1 1,128 2 Fall River | In ordinary use After standing in pipe. . .0070 .0103 1 49 ^ Metropolitan J In ordinary use .0000 \ Brass supply \ After standing in pipe. . .0000 / 92 1 (Report Massachusetts State Board of Health, 1900, page 495.) The effects on ground and surface waters that are con- ducted through galvanized iron service pipes can be judged from the results in Tables XXVII and XXVIII. TABLE XXIX. Copper in Samples of Ground Water (PARTS PER 100,000.) LOCALITY SAMPLES TAKEN Copper (Average) Average Length of Brass Pipe (Feet) Average Size of Pipe (Inches) Wellesley 1 Lowell (boulevard J wells) 1 Lowell (cook and f hyd, wells) \ In ordinary use. . ...... After standing in pipe. . In ordinary use. .. . After standing in pipe. . In ordinary use After standing in pipe. . .(}2r.7 .((■2h0 .007(5 .02.33 . 0000 \ (50 1 DO 1 ^'■' Us H •"Chemical News" X — X — '85. Digitized by Microsoft® 126 Principles and Practice of Plumbing To briefly sum up, it may be stated that it is always better to determine experimentally the action of water upon pipes than to try and predict it from knowledge of the char- acter of the water. It is better still to only use pipes that are not affected to any appreciable extent by the solvent action of any water. If, however, pipes must be used that are so affected, then those should be selected, the dissolved metals of which are the least injurious to the human system. The necessity of using pipes that are not injurious is manifest, when it is considered that a water which is per- fectly wholesome and non-solvent may be changed at any time for a different supply that might energetically attack the pipes, or, the character of the water itself might change sufficiently to dissolve the metal. Copper is also dissolved from brass pipes, as may be seen from Tables XXIX and XXX of analysis of ground and surface waters drawn from brass service pipes. TABLE XXX. Copper in Samples of Surface Water (PAEa?S PEE 100,000.) LOCALITY SAMPLES TAKEN Copper (Average) Average Length of Brass Pipe fKcet) Average Size of Pipe (Inches) Maiden f Metropolitan i supply 1 Liiwrence | ■W'akefield ) In ordinary use After standing in pipe. . In ordinary use /Vfter standing in pipe. . In ordinary use After standing in pipe. . In ordinary use After standing in pipe. . .0000 .0470 .OOoO .0000 .0(K)0 .0000 !oooo 'A 1 Vi The effect of some water upon different metals of which water pipes are made or coated, and the resultant effect upon the health of those drinking the waters are shown in Table XXXI. The action of water upon galvanized iron pipes is almost as energetic as upon lead pipes, and under suitable conditions will dissolve equal amounts of metal from each. However, the effect of the zinc upon the health is not dan- gerous but only injurious, because zinc is not a cumulative Digitized by Microsoft® Principles and Practice of Plumbing 127 TABLE XXXI. Effect of Metals on Health Kind of Pipe Action of Water Effect upon People Lead pipe Dissolves lead. . . Dangerous No effect Tin or tin lined lead No effect - (ialvanized iron Dissolves zinc Injurious Tin lined iron No effect No effect Brass pipe . Slightly dissolves copper and zinc. . . Rusts and dissolves Objectionable Objectionable No effect *Plain iron . . Nickel. . No effect No effect Benedict Nickel No effect No effect Copper Dissolves Copper Slightly No effect 'Dissolved iron or rust in small quantities is not injurious to health, but 'A grain of iron per gallon of water imparts an objectionable taste to the water besides making it unfit for washing and for most manufacturing purpo.ses. poison, and so long as the initial dose is not sufficient to cause illness or death, the effect is soon thrown oflf without apparent injury. Lead, on the contrary, even when taken in small doses, remains in the system until sufficient poison accumulates to cause serious illness or death, or if the initial dose is of sufficient strength the effect may be immediately fatal. Lead pipes are used for water supply in building. Sheet lead also is used for lining water tanks. Within the past few years, however, a rational decrease in the use of lead supply pipes and lead lined tanks is noticeable. Galvanized iron pipes, which are cheaper and better in every way, are fast supplanting lead pipes, and when perfect security from metal poisoning is desired, Benedict nickel seamless tubing, tin-lined lead or tin-lined iron pipes may be used. From a hygienic standpoint, Benedict nickel and tin-lined pipes are about equal, but when superior finish is desired the Benedict nickel tubing will be found the more satisfactory. In appearance it is equal to nickel-plated brass pipe, and in all other respects superior to it. Absorption of Gases by Water. — Water has a certain affinity for most gases. This affinity is more pronounced for some gases than for others ; for instance, at atmospheric pressure and at ordinary temperatures, pure water will absorb 4 per cent, of its own volume of air, 4 per cent, of its Digitized by Microsoft® 128 Principles and Practice of Plumbi7ig volume of sulfureted hydrogen, or 100 per cent, of its volume of carbonic acid gas. By increasing the pressure on the water its capacity for absorption is increased in direct proportion. That is, if the pressure be increased to two atmospheres, the temperature remaining unchanged, pure water will absorb 8 per cent, of its own volume of air, 8 per cent, of its volume of sulfureted hydrogen or 200 per cent, of its volume of carbonic acid gas. Heating water lessens its capacity for absorption in direct proportion to the amount of heat applied. The rela- tive volume of gas absorbed is in all cases directly as the pressure and inversely as the temperature. Thus, if the pressure be increased it will absorb more gas, and if it be heated it will absorb correspondingly less gas. Water is saturated when it has in solution all the gas it can hold. If water is saturated with gas and the pressure is then increased or the temperature lowered, the capacity of the water to hold gas will be increased and it will absorb still more. If water is saturated with gas and the pressure is reduced or its temperature raised, the capacity of the water to hold gas will be reduced and some will be liberated. It is due to the fact that increasing the pressure of water increases its capacity to absorb gases that necessi- tates frequent recharging of air chambers in pipe systems. Water usually enters a supply system from a pump or reser- voir at atmospheric pressure, saturated with air. As the water becomes compressed, however, its capacity to absorb air is increased, hence, when passing an air chamber the water absorbs air from the chamber, which in turn grad- ually fills with water. The fact that decrease of pressure liberates air from saturated waters determines the best place in a system to locate air chambers. When a faucet is opened the pressure of water at that point is considerably reduced ; furthermore, in passing through the system of piping within the building the water has become slightly warmed; hence, if an air chamber is located immediately above the faucet, gases lib- erated from the water will rise into the air chamber and keep it charged. Digitized by Microsoft® Principles and Practice of Plumbing 129 CHAPTER XIV HYDRODYNAMICS HYDROSTATICS Laws of Hydraulic Pressure The Hydraulic Gradient. — The surface of water at rest is always level. If two or more vessels are connected together near their bottoms and water is poured into one vessel, it will flow through the connecting pipes to the sev- eral vessels until the surface of water in all of them is at the same level. If water in the system of piping, Fig. 62, be at rest, it will stand in all of the branches open to the atmosphere at the top at the same level d as the water in the tank. This lined is called the hydrostatic gradient. If the cock h be now opened the water in the several branches will fall to the dotted line c drawn from the surface of the water in the tank to the outlet of the cock. "This line is known as the hydraulic gradient, and its distance above a pressure main determines the available pressure head at that point, when water is flowing through the pipe. It should be noticed that the pressure head differs from the hydrostatic head; the latter is equal to the vertical distance from the water pipe to the hydrostatic gradient d, while the pressure head is equal to only the vertical distance from the water pipe to the hydraulic gradient c. When water from one tank or reser- voir discharges into another tank or reservoir at a lower level, the hydrostatic gradient becomes an imaginary line drawn from the surface of water in the upper tank or reservoir to the surface of water in the lower one. An open conduit between two such reservoirs will conduct water from the higher to the lower one without overflowing the conduit, provided the conduit follows the line of the hydraulic gradient and at no point rises above nor dips below it. When running siphon pipes or other closed conduits from a reservoir or other source of water supply to a build- Digitized by Microsoft® 130 Principles and Practice of Plumbing ing, care should be taken to keep the pipe below the hydraulic gradient. When, however, it is impracticable to do so, a relief valve or open vent should be provided at the highest point of the line where it rises above the hydraulic grade. If means are not provided to permit the escape of air from the pipe, it will accumulate at this point until it fills the bend of the pipe and by forming an air lock might completely stop the flow of water. If the flow of water is not completely stopped, other important changes will result ; if a vacuum gauge is attached to the pipe at any point where it rises above ,the hydraulic gradient it will show a partial vacuum; this vacuum will cause air to collect at the highest point in the pipe and the flow of water will become broken until finally the pipe will be filled only to the point where it rises above the hy- draulic gradient and will dis- charge at this point as though discharging into ' the air. From the highest point to the outlet, the pipe will be only partly filled and will act as a flume or channel to carry off the water. Pressure of Water. — The unit of water pressure is the pound per square inch. The pressure exerted by water is due to its weight and is determined by the height of the, column of water. For instance, if the pressure exerted by a force pump is 50 pounds per square inch it will balance a column of water about 115 feet high. This pressure, there- fore, is equivalent to a head of water 115 feet deep. Head of water at a given point is the vertical distance between that point and the level of the surface of the water. In meas- uring the depth or static head of water, the vertical distance from the hydrostatic gradient to the point of consideration Fig. 62 Hydraulic Gradient Digitized by Microsoft® Principles and Practice of Plumbing 131 is always taken regardless of lateral or horizontal distances from the point. The weight of a column of water one inch square and 12 inches high equals .434 pound. It is just 1/144 the weight of one cubic foot of water which has the same depth of column but 144 times the area. When the height of a column of water is known, its pressure in pounds per square inch can be determined by multiplying the height in feet by .434*, the weight of one foot of water 1 inch square. Example — Wliat is the pressure per square inch at the base of a column of water 200 feel high? Solution — 200 X -434 = 86.8 pounds per square inch. When the pressure is known the height or head of a column of water can be found by multiplying the pressure in pounds by 2.3, the height of a column of water weighing one pound. ExAMPLK — Wliat must In- the height of a column of water to exert a pressure of 86.8 pounds per square inrh? SotuTiON— 86.8 X 2.3 = 199.64 feet head. The constants .434 and 2.3 although used in practice are not exactly correct, as can be seen by .comparing the two foregoing examples. Heads and corresponding pressures of water in pounds per square inch for every foot in height to 240 feet can be found in Table XXXII. Pascal's Law of Pressure. — -Water confined in a ves- sel and subjected to a pressure, transmits the pressure with the same intensity in all directions. This law was first dis- covered by Pascal, and is expressed as follows : "The press- ure per unit of area exerted anywhere upon a mass of liquid is transmitted undiminished in all directions, and acts with the same force upon all surfaces, in a direction at right angles to the surfaces." Measuring Pressure. — The pressure of water in closed systems is indicated by a pressure gauge. The construction *TJio constant .434 will be found sufficieutl.v accurate lor most calculations, and wbeu an approximation only is required tbe constant .4 will suffice. Digitized by Microsoft® 132 Principles and Practice of Plumbing TABLE XXXII. Heads and Pressures of Water Pressure Pressure Pressure Pressure Pressure Feet Head per Sq. Inch Feet Head per Sq. Inch Feet Head per Sq. Inch Feet Head perSq. Inch Feet Head perSq. Inch 1 0.43 49 21.22 97 42.01 145 62,81 193 83,60 2 0.86 50 21.65 98 42.45 146 63,24 194 84,03 3 1,30 51 22.09 99 42.88 147 63,67 195 84,47 4 1.73 52 22.52 100 43.31 148 64,10 196 84,90 5 2.16 53 22.95 101 43.75 149 64,54 197 85.33 G 2.59 54 23,39 102 44.18 150 64,97 198 85.76 7 3.03 55 23,82 103 44,61 151 65,40 199 86.20 8 3.46 56 24,26 104 45.05 152 65.84 200 86,63 9 3.89 57 24,69 105 4.T.48 153 66.27 201 87,07 10 4.33 58 25,12 106 45,91 154 66.70 202 87.50 11 4.76 59 25,55 107 46,34 155 67.14 203 87,93 12 5.20 60 25,99 108 46,78 156 67.57 204 88,36 13 5.63 61 26,42 109 47,21 157 68.00 205 88,80 14 6.06 62 26.89 110 47,64 158 68,43 206 89,23 15 6.49 63 27,29 111 48,08 159 68,87 207 89,66 16 6.93 04 27,72 112 48,51 160 69,31 208 90.10 17 7.36 65 28,15 113 48,94 161 69,74 209 90.53 18 7.79 66 28,58 114 49,38 162 70,17 210 90.96 19 8.22 67 29,02 115 49,81 163 70,61 211 91,39 20 8.66 68 29,45 116 50,24 164 71,04 212 91,83 21 9.09 69 29,88 117 50,68 165 71.47 213 92.26 22 9.53 70 30,32 118 51,11 166 71,91 214 92.69 23 9.96 71 30,75 119 51,54 167 72,34 215 93,13 24 10.39 72 31,18 120 51,98 168 72,77 216 93,56 25 10.82 73 31,62 121 52,41 169 73,20 217 93,99 20 11.26 74 32,05 122 52,84 170 73,64 218 94,43 27 11.69 75 32,48 123 53,28 171 74,07 219 94,80 28 12.12 76 32,92 124 53,71 172 74,50 220 95,30 29 12.55 77 33,35 125 54,15 173 74,94 221 95.73 30 12.99 78 33,78 126 54,58 174 75,37 0*70 90.16 31 13,42 79 34,21 127 55,01 175 75.80 22.3 96.60 32 13.86 80 34,65 128 55,44 176 76.23 224 97.03 33 14.29 81 35,08 129 55,88 177 76.67 225 97.46 34 14.72 S2 35,52 130 56,31 178 77.10 226 97.90 35 15.16 83 35,95 131 56,74 179 77.53 227 98.33 36 15.59 84 36,39 132 57,18 180 77.97 228 98.76 37 16.02 85 36,82 133 57,61 181 78.40 229 99.20 38 16.45 86 37,25 134 58,04 182 78.84 230 99.63 39 16,89 87 37,68 135 58.48 183 79.27 23r 100.06 40 17,32 88 38,12 136 58,91 184 79.70 232 100.49 41 17,75 89 38,56 137 59,34 185 80.14 233 100. 93 42 18,19 90 38,98 138 59,77 186 80.57 234 101 . 36 -13 18,62 91 39,42 139 00,21 187 81.00 235 101 . 79 41 19,05 92 39,85 140 60,04 188 81.43 236 102.23 45 19,49 93 40,28 141 61,07 189 81,87 237 102,66 46 19,92 04 40,72 142 61,51 190 82,30 238 103,09 47 20.35 95 41,15 143 61,94 191 S2,73 239 103,53 48 20,79 96 41.58 144 62,37 192 83,17 240 103,96 Digitized by Microsoft® Principles and Practice of Plumbing 133 ftf a pressure gauge is shown in Fig. 63. In this illustra- tion the dial face is removed to show the interior construc- tion. A bent tube a, of elliptical cross-section, made of metal of the required elasticity, has its bottom end firmly attached to the gauge case, and its upper end left free to move. To the upper end is at- tached a lever b, which is so con- nected to a pointer in front of a graduated index dial that any movement of the tube will be indi- cated by the pointer. The principle of its operation is as follows: If a bent tube of elliptical cross section be subjected to an internal pressure, the force exerted will tend to straighten the tube. This is due to the fact that a force exerted within a tube of elliptical cross section tends to make it take a circular form ; to do so, the inner arc of the bent tube must lengthen and the outer arc shorten and the combined effort will straighten the tube in direct propor- tion to the pressure exerted. The straightening of the tube imparts a movement to the register hand which indicates on the face of the gauge the intensity of the pressure. Fig. 63 I'ressiire Uanj; Digitized by Microsoft® 134 Principles and Practice of Plumbing CHAPTER XV FLOW OF WATER THROUGH PIPES Friction in Pipes. — The flow of water through pipes is accelerated by gravity -and retarded by friction. If it were not for the frictional resistance in pipes, water would flow through them with a velocity equal to eight times the square root of the head. As it is, the roughness of the interior walls, the bends and branch fittings in a system of piping offer so much frictional resistance that the actual mean velocity is but a fraction of the theoretical velocity. The pressure head at any point is less than that due to the hydrostatic head. This difference between the hydro- static head and the pressure head is known as loss of head, and is greater the smaller the pipe or the greater the veloc- ity of flow. The loss of head is due to three causes — loss of head due to entry, loss of head due to bends, and loss of head due to the length and area of the pipe. The Contracted Vein. — The flow of water through a circular aperture in a thin plate. Fig. 64, is contracted in size a short distance outside of the plate to .615 the area of the aperture, but expands again to the full size of the opening. The point of greatest contraction is at a distance from the plate equal to about one-half the diameter of the aperture. ■ In consequence of this contraction, the velocity of flow is slightly reduced from the theoretical velocity and the quantity discharged is greatly reduced. This contraction is known as the coiitrdcted vein. When the aperture is through a plate of considerable thickness or through a tube the length of which is not less than twice the diameter of the pipe, the contraction is still found to occur, but to a less extent than in the former case ; the vein being contracted, as shown in Fig. 65, to only .8 of the theoretical area due to head and aperture. Loss due to the contracted entrance of water from a tank or cylinder into the end of a pipe, as commonly found in practice, must be taken then as .2 the quantity that Digitized by Microsoft® Principles and Practice of Plumbing 135 Fig. 64 Contracted Vein should pass. This loss is known as loss of head due to entry and is considered separate from the loss due to fric- tion in long pipes, loss for bends, branches, etc., and should be-added thereto. The actual loss of head due to entry can be reduced to a quantity too small to be considered by enlarging the en- trance to the pipe and making it cone shaped, as in Fig. 66. The cone should have a length a, equal to one-half the diameter of the pipe, and a radius 6, equal to 1.22 diameters of the pipe. Any greater enlargement of the opening w^ill deduct but little from the loss of head. If the ends of thick pipes or pipes of small diameter which are relatively thick are reamed'^with a reamer, the length of which is just twice the base, enough metal will be re- moved to give almost the best form of contracted vein. When an unreamed pipe projects a short distance in- side of a tank the loss of head due to entry is greater than when the pipe finishes flush with the inside of the. tank. This loss of head has been found by experiment -to be over .3 of the whole flow, thus de- creasing it one-tenth more than a pipe that finishes flush with the in- side of a tank. Loss of head due to entry can be determined by the formula : l = c-— When ] = loss of bead in feet, v = velocity of flow in feet per 2g second, g = 32.16, acceleration due to gravity, c == coefficient depending on shape of the pipe inlet. For ordinary calculations the value of c may be taken as .5. Example — What is the loss of head due to entry in a pipe when the velocity of flow is 8 feet per second? Si^s^ss^ ' C'.^^■^^^w■ ^ ■^'. ■ ^^.^^^'.»J Fig. G5 Water Flowing Tlirougli Short Tube Solution — 1 : : .5 ^i- = .497 feet. 64.32 Answer. Digitized by Microsoft® 136 Principles and Practice of Plumbing Fig. OG Cone Shaped Entry to Pipe Loss OF Head in Bends. — The loss of head, due to bends in a pipe, depends upon three factors. First, loss due to change of direction of the water in the pipe ; second, loss from friction as in an ordinary straight length of pipe; third, loss due to enlargements or contractions in the bend, such as are formed when the unreamed ends of pipe are screwed into ordinary elbows. The second and third losses also apply to couplings and tees, but the loss is not the same as for bends of equal diameters. The loss of head for change of direction differs with the angle and with the radius of the bend. That is, there is less loss for change of direction in a forty-five degree bend than in a ninety-de- gree bend, and the loss is greater in a bend of one diameter radius than in one with a radius of two diameters. The loss in a ninety degree bend with a radius of five or more diameters and uniform smooth interior bore is no greater than in an equal length of straight pipe. In other words, there is practically no loss for change of direction in a bend of greater radius than 5 diameters. The head lost in a ninety degree bend of less than 5 inch diameter and of the radius commonly found in practice, radius=diameter, with square unreamed ends of pipe screwed into the fitting, as shown in Fig. 67, is found by experiment to be five times as great as in bends, which the pipes have reamed ends. The friction loss in bends having reamed pipes screwed therein, is given in Table XXXIII for various sizes of pipe. It will be observed that the larger the size of the pipe, the greater the equivalent length of pipe the friction in the bend equals. In the experiments from which these tables were derived, the ends of the pipes were reamed and filed iSi Fig. 07 Friction in iU'ntlM Digitized by Microsoft® Principles and Practice of Plumbing 137 out to such an extent that there was practically no decrease of diameter at these points. TABLE XXXIII. Friction in Pipe Bends Diameter of Bend in Inches Friction in the bend is equal to the friction in number of feet of straight pipe listed Friction in the bend equals the friction in corresponding sizes of straight pipe of the following lengths 5 4 3 2 IV2 IM 1 20 feet of straight pipe 15 feet o£ straight pipe 9 feet of straight pipe 5 feet of straight pipe 3 ft. 3 in. of straight pipe 2 ft. 6 in. of straight pipe 1 ft. 6 in. of straight pipe 48* diameters of fitting 45 diameters of fitting 36 diameters of fitting 30 diameters of fitting 26 diameters of fitting 24 diameters of fitting 18 diameters of fitting *Thus, 18 diameters of 1 inch pipe equals 18 Inches of straight pipe. For use in practice the value given in Table XXXIV may be taken as the approximate ratios between the fric- tion of ninety degree bends and other fittings of the same size. TABLE XXXIV, Friction of Fittings Kind of Fitting Number of 90° bends it is equal to in frictional resistance C'oupUng 45° elbow Open return bend (open pattern) Tee fitting Gate valve Globe valve One-^tenth of 90° bend. About twice the friction of corresponding length of straight pipe. One-half the friction of a 90° bend. Same as 90° bdhd. Equals friction in two 90° bends. One-half the friction of a 90° bend. Equals friction in twelve 90° bends. In pipes of larger diameter than 5 inches, these ratios would hold true, but the number of diameters of straight pipe a fitting would equal in frictional resistance would increase in proportion and can be found by interpolation. The loss of head in small fittings when the ends of the pipe screwed into the fitting are reamed, as shown in Fig. 68, is found by experiment to be less by about five times as when the pipe ends are not reamed. For instance, in a 1 inch ninety degree bend, with reamed pipe ends, in which Note: Tables XXXIII and XXXIV based on experiments made by Pro- fessor F. E. Geisule, School of Architecture, Austin, Texas. Digitized by Microsoft® 138 Principles and Practice of Plumbing the friction is equal to friction in a pipe of a length of 18 diameters, this loss of head would be divided into : Loss of head due to change in direction 12 diameters Loss of head due to enlargement of the bend 4 diameters Loss of head from friction due to length of fitting 2 diameters Total In a bend having Fig. 68 Elbow Witli Beamed Pipes tively shown as follows : 18 diameters unreamed pipe ends, the friction would be about 5 times as great, or equal- to 5 X 18 = 90 diameters of the pipe. The loss of head in a bend of five or more diameter radius, with flush interior joints. Fig. 69, is equal to the loss of head in a length of pipe four diameters of the fitting. This is compara- Loss of head due to change of direction diameters Loss of head due to enlargement of the bend diameters Loss of head from friction due to length of pipe 4 diameters Total 4 From the foregoing it will be seen that the least possi- ble head is consumed by using fittings of large radius with flush joints. That when common fittings are used the loss can be reduced to one-fifth by reaming the ends of the pipe with a triangular-shaped reamer, the length of which is just double the base. The values for friction loss in fittings given in the preceding tables are relative and for low velocities, not over 1 foot per second. With an increase in velocity, how- ever, there is an increase in frictional re- sistance, so for greater velocities the friction will have to be approximated by calculation. Fig, 69 Friction in Flush Fitting Digitized by Microsoft® Principles and Practice of Plumbing 139 The loss of head in feet due to bends can be calculated by the formula : h = n — in which h = head lost in feet, v = velocity in feet per second, 2g g = 32.16 acceleration due to gravity, n := a coefficient for the bend. The value of coeflScient n depends upon the ratio between the radius r of the pipe and the radius R of the bend. Table XXXV gives values of n corre- sponding to various values of the ratio . R Example — ^What will be the loss of head in a column of water flowing with a velocity of 8 feet per second through a 4-inch bend that has a radius R of 4 inches? Solution — ^The radius i of a 4-inch bend = 2 inches, therefore, R which is 4 inches will = 2r, which gives for n the value .29. Substituting values in the formula then gives, h r= .29 X = -287 foot. Answer. 64.32 TABLE XXXV. Values of Coefficient N r R R=r -R = 1.12r R = 1.25r R = 1.4r R = 1.6r R = 2r R = 2.5r R = 3.3r R = 5r n 1.98 1.41 .98 .66 .44 .29 .21 .16 .14 Loss OF Head in Straight Pipes. — Loss of head in straight pipes is caused entirely by the frictional resistance of the walls of the pipes ; the rougher the walls, the greater the amount of frictional resistance offered to the flow. Frictional resistance in pipes may be summed up in three general laws, viz. : 1. Frictional resistance in a pipe varies directly as the length of the pipe. That is, the total amount of friction offered in a pipe 100 feet long is twice as much as in a pipe 50 feet long, of equal diameter and -smoothness, and one- half as much as in a pipe 200 feet long. 2. Friction varies inversely as the diameter of the pipes. That is, in a pipe 2 inches in diameter the frictional resistance is proportionately less by one-half than in a pipe 1 inch in diameter. The reason is that frictional re- sistance is in direct proportion to the area of the surface of water and walls of pipe in contact. This surface is known as the wetted perimeter, and in a pipe 2 inches in diameter is but twice as great as the surface in a 1 inch pipe, while Digitized by Microsoft® 140 Principles and Practice of Plumbing the cross sectional area of the 2 inch pipe, it will be remem- bered, is 4 times as great as that of a 1 inch pipe. This is well illustrated in Fig. 70. In the four 1 inch pipes, a, b, c, d, the length of the wetted perimeter is just 13.16 inches. If the four 1-inch pipes be now converted into one 2-inch pipe by removing the sections marked with dotted lines and rolling the heavy lined sections back to e, the wetted perimeter will be reduced to 6.49 inches, or about one-half the length of the combined perimeters of the four 1-inch pipes, while the sectional area remains unchanged. 3. Friction varies almost as the square of the velocity and is entirely independent of press- ure. That is, if the velocity of flow of water in a pipe is doubled, the frictional resistance will be quad- rupled, while if the initial velocity is reduced to one-half, the frictional re- sistance will be decreased to one- quarter, regardless ■ of the intensity Pig. 70 of pressure in the pipe. wettea Perimeter of Pipes Loss of head due to frictiou in pipes can be determined by the formula: Iv li = f , in which h = loss of head in feet, f = coefficient for size and rough- ness of pipe, 1 = length of pipe in feet, v = velocity in feet per second, d ^= diameter of pipe in feet, g = 32.16 acceleration due to gravity. The value of coefficient / for different sizes of pipes TABLE XXXVI. Values of Coefficient /- (MEKRIMAN) Diameter of Pipe in Velocity of Feet per Second Ft. In. 1 2 3 4 6 10 15 .05 Vs .047 .041 .037 .034 .031 .029 .028 .1 114 .038 .032 .030 .028 .026 .024 .023 .25 3 .032 .028 .026 .025 .024 .022 .021 .5 6 .028 .026 .025 .023 .022 .021 ,019 .75 9 .026 .025 .024 .022 .021 .019 .018 1. 12 .025 ,024 .023 .022 .020 .018 .017 Digitized by Microsoft® Principles and Practice of Plumbing lil and with different velocities of flow can be found in Table XXXVI. Example — What is the loss of head due to friction in a 3-inch pipe 600 feet long, if the mean velocity of flow is 4 feet per second? Solution — From the taljle it is found that the value of / for a 3-inch pipe with a velocity of 4 feet per second is .025; then, substituting given values in the formula: 600 X 16 h = .025 X = 15 feet.— Answer. .25 X 64.32 Table XXXVII gives the loss of head in pounds per square inch for each 100 feet of length in different sizes of clean pipes discharging given quantities of water per minute. If the loss of head is desired for the same diameters of ■pipe but for different lengths than those given in the table, when discharging the given quantities of water, it can be found by multiplying the loss of head by the ratio of the length of pipe. For instance, according to the table there is a loss of head of 13 pounds in a %-inch pipe when dis- charging 10 gallons of water per minute, and, as friction, hence loss of head, is in direct proportion to the length of a pipe, velocity and diameter remaining the same, it follows that in a %-inch pipe 200 feet long, discharging 10 gallons of water per minute, the loss of head would be 26 pounds, or double that in 100 feet of pipe. Likewise, in a pipe of equal diameter but only 50 feet long, discharging 10 gallons of water per minute, the loss of head would be 6.5 pounds, or one-half that of 100 feet of pipe. If the loss of head expressed in pounds is desired in feet, it can be found by multiplying the loss of head in pounds by 2.3. The size of pipes and quantity of discharge being given in this table, the velocity of flow can be found by dividing the quantity by the area of the pipe. Velocity of Flow. — When water flows through a pipe of uniform Cross section, the quantity of water passing any point in a given interval of time depends upon the velocity with which the water flows and the area of cross section of the pipe. It is evident that the quantity of water will equal a column whose cross section is the area of the pipe and whose length is equal to the velocity. Digitized by Microsoft® 142 Principles and Practice of Plumbing paSjBqDsiQ suoiiBO lOO '0 OiOO MiNCO lO t> O d d d d d d d 41 i. puooag Jad :j33jI ut it:jpopA CO e MOO'* OSiOW b- O (M CI CO CO ■* lO j3 spanoj UI sso^ uoii(dt"jj o o CO CO d d (NfficD lOCC-H CO r-l l-KN CO***!© [^ bn puooag j3d ^aajl UI A:^poIaA CM CO i-IcO<© OlWiO 00 lOcCih- WOi-H (N CO spunoj ui ssoq uopojjji o d COI>CO C3MG0 Ot-(N M'CiO CO OOi-H r-lCflCO lOb-i-H "5 0*S O o 1 © puooag J3d U33d ui X:,jDopA CO I^OtP t^T-H ^ CO iMtJ^iO OOOOi OCOCi Oi«Tt< t-- MCO"* >0Ot^ OJ'Hco lOQOO CI .9 eg spunoj UI ssoq uoi^dujI OI d iHOO OOCO c&eoco d»-«co -^V-'d (n'osco in Pounds, in 10 . ELLIS, C. E.) puooag j3d laaj UI A:nDopA ' g (MCT>S ^oOtJ) wcoeo co-^co oooi'-H eodOJ n spunoj UI ssoq uoi;oujI IM d CM d d o "* CO Tj< oj w iH ira IN 'O Ol "* t-i W t- .-IC^Cm CO puoDag Jtad ^33^ UI A^popA ° CO .-1© lo t^ d w lO t^ d •g spunoji ui amy I uoT^oijji (NI^I> CDCNiO lOIMiO tHtPO "©Xit^ OiOr-« OtPO OOO .-(MM lOtOW OiMCl T--(NcO puooag J3(J ^33jI ui AiioopA rHCNcO CCTt<>Cl OcOt- CO OiGOr-- cDiOTt* CO(MW OtO(N oVicq coTtito oVoo ojco'oo J3 .9 spuno^ UI ssoq uopDUjj .-1 lO 00 t-- O 'O COOCC O'**^ TjtrttM OJi-H O'l-iw ^'tDoi (n'oO ^P 09 puooag Jad ^aajl UI ^:»popA CoJoS CqfoOT i^'^b- r-ICO tHNCC lOCOt^ OlOiH cOOi spunoj UI SSCr[ UOT^DUjJ TfCOOO puooag Jad ^aa^ UI A;popA TfOOCO t^ OOfH T-((MCO COCO M 'S^" to CO d (n" Tji «:i ■g spunoj UI ssoq uoi^iojj^ puooag jad laan "1 ^^popA «1>0 "*00 n g ■g .9 spunoj UI ssoq uopouj; (DO sis puoaag jad ijaaji UI A^popA COi 2 2K 3 4 5 6 6.3 10.9 17.2 35.3 61.7 97.4 199.9 349.2 555.5 1133. 1976. 3116. 5.4 9.5 14.9 30.6 53.5 84.3 173.1 302.4 477.1 979.3 1711. 269S. 4.4 7.7 12.2 25.0 43.7 68.7 141.4 246.9 390.1 800.8 1394. 2204. 3.6 6.3 9.9 20.4 35.6 56.2 115.4 201.6 317.8 653.8 1141. 1799. 3.1 5.5 8.6 17.7 30.9 48.7 100. 174.6 275.8 566.2 987.7 1558. 2.8 4.8 7.7 15.8 27,6 43.9 89.4 156.2 246.7 506.5 883.5 1384. 2.6 4,4 7.0 14.4 25.2 39.8 81.6 142.6 225.2 463.2 806.5 1272. 2,4 4.1 6.5 13.4 23.3 36,8 75.6 132.0 208.5 428.0 746.7 1178. 2.2 3.9 6.1 12.5 21.8 34.4 70.7 123.5 195.1 399,0 698.5 1102. 2.1 3.6 5.7 11.8 20.6 32.5 66.6 116,4 183,9 377,5 658,5 1039. 2.0 3,5 5,4 11,2 19,5 30.8 63.2 110.4 174,5 358,1 624.7 985.5 From this table the discharge of any length of pipe under any head used in practice can readily be determined. The abbreviation H stands for head, and L for length. Checking up the table with the formula for quantity and the example worked, it will be found that they agree almost exactly. The problem is to find the quantity of water that can be delivered per minute through a 3-inch pipe 2,000 feet long, under a head of 400 feet. According to the example worked out, the pipe has a capacity of 32.97 cubic feet per minute. As there are 7.47 gallons in a cubic foot, the capacity of this 3-inch pipe in gallons is 246.28 per minute. Now, a pipe 2,000 feet long with a head of 400 feet has a ratio of Head equal to 1/5 its length ; and looking on the table it will be found that a 3-inch pipe having a head of 1/5 length, has a capacity of 246.7 gallons per minute, thereby varying from the answer to the example less than one-half gallon per minute. Digitized by Microsoft® Principles and Practice of Plumbing 147 CHAPTER XVI MEASUREMENT OF WATER TYPES OF WATER METERS Velocity Meters Classification of Meters. — The quantity of water flowing uninterruptedly through a pipe may be approxi- mately determined either by calculation or by measurement. When the flow of water is intermittent, however, the quant- ity can be determined only by measurement. The manner of determining the flow of water by calculation has already been explained. It is measured by means of an apparatus called a water meter. Water meters may be divided into two general classes : Velocity or inferential meters, and volume or positive meters. Velocity meters measure the velocity of water passing through them, and, the size of the discharge orifice remaining constant, the velocity per foot equals a certain quantity which is automatically computed and indicated on an index dial. Volume meters measure the volume of water passing through them and automatically register the quant- ity on an index dial ; they operate by alternately filling and discharging a chamber of known capacity. VeNturi Meter. — The simplest form of velocity meter is the Venturi meter, Fig. 71. This meter may be had in sizes ranging from 2 inches to 60 inches in diameter, and fitted with an index dial, a recording register; or with a manometer gauge, a, which simply indicates the rate of flow. The meter operates on the principle that when water flows through a contraction in a tube of the shape and rela- tive cross sections of a Venturi meter tube, there is a tem- porary reduction of pressure at the throat b, which is approximately proportional to the square of the velocity. This reduction of pressure at the throat causes an unequal pressure in the pressure pipes c and d, which are connected respectively to the pressure chamber e on the inlet end of Digitized by Microsoft® 148 Principles and Practice of Plumbing the tube and the pressure chamber / at the throat of the tube. This unequal pressure depresses the mercury in the leg g of the manometer and causes it to rise correspondingly in the other leg; a properly graduated scale showing the difference between these two mercury levels, indicates the velocity of flow through the meter. Having the velocity of flow and knowing the area of cross section of the meter, the quantity of water passing through in a given time can be calculated by multiplying the velocity for that period of time by the cross sectional area of the meter tube. The Gem Meter. — Fig. 72 clearly illus- trates the construction and principle of operation of a mechanical type of velocity" meter. Water enters the cylinder from be- low and in rising presses against the pro- peller blades a, causing them to revolve in direct proportion to the velocity of the water flowing through the meter. The speed of the propeller is so adjusted that a certain number of revolutions equals a certain num- ber of gallons or cubic feet which are auto- matically indicated on an index dial. Volume Meters The Hersey Disk Meter. — Fig. 73 dis- charges a known quantity of water at each gyration of the disk a, and is there- fore a positive or vol- ume meter. The principle of its operation is as follows: Water entering the meter passes through a perforated metal screen b to remove all coarse particles of matter that might interfere with the operation of the meter. The water enters the disk chamber on top of the disk a, and exerts a pressure there at the same time that the pressure is re- leased in the discharge chamber. This uneven pressure Fig. 71 A't'iiliirl Motel" Digitized by Microsoft® Principles and Practice of Plumbing 149 causes the disk to gyrate, rising on the inlet side and lower- ing on the discharge side, so that water now enters and presses on the under side of the disk which again gyrates and brings the pressure to the upper side of the disk. The disk is thus alternately raised and lowered at the inlet and outlet ports at each gyration of the disk as long as water is flowing through the pipe. At each gyration of the disk an amount of water equal to the entire contents of the disk cylinder is discharged and each gyration indicates on the index dial the amount of water that passes through the meter. Meter Accessories Fish Traps. — In localities where the water supply is •obtained from "rivers, lakes, reser- voirs or other surface sources, fish traps should be used to prevent the introduc- tion of fish, algse, weeds or objects that might interfere with the operation of the meter. Some meters have a strain- er covering the inlet and forming part of the meter. Such a strainer is shown at b, in Fig. 73. When a strainer does not form part of the meter, a separate strainer or fish trap should be used. In localities where the water is extremely dirty or carries large quantities of mat- ter in suspension, a strainer. Fig. 74, formed of hinged brass strips, will be found more satisfactory than a perfor- ated strainer, Fig. 75, owing to the ease with which the hinge strainer can be removed and cleaned. Water meters should be located in an accessible place safe from frost. Where there is danger of hot water being forced backward through a meter a check valve should be placed in the supply pipe to protect the indurated rubber parts from being damaged by the hot water. Special water meters, the working parts of which are made of bronze metal, are made for metering hot water. Venturi tube meters have no parts that can be affected by //7/tf/ Fig. 72 Velocity Meter Digitized by Microsoft® 150 Principles and Practice of Plumbing Fig. 73 Volume Meier the action of hot water, and may also be used for that pur- pose. Loss OF Head in Meters. — There is considerable loss of head in small meters, but this loss grows less and less as the size of the meter increases, until above 6 inches in diameter it is almost a negligible quantity. In small house meters, however, it is a matter of considerable moment, as the loss of head re- quires twice the length of time to discharge a given quantity of water through a meter that would be required to discharge it merely through a pipe of the same length. In Table XL will be found the relative lengths of time required for the ilow of various quantities of water through meters of different sizes, and through the connections only. These tests were made on disk meters by the Bureau of Water, Chicago. The tests were all made under a pressure of 30 pounds to the square inch. Water Meter Rates. — The only sane and logical way to sell water is by meter rates, just as other commodities are sold. By this method waste will be prevented, each con- sumer pays for only what he actually uses, whereas under the price-per-house method, the careful householder pays for the extravagance of his careless town people. ' There are no good objections to selling water by meter rates. The only one worthy of considering is the fact of Fig. 74 Fisli Trap Digitized by Microsoft® Principles and Practice of Plumbing 151 Pig. 75 Meter Strainer great loss of head in passing through the meters. How- ever, the saving affected by selling the water by measure instead of by time, will save the head necessary to force the water through the meters. Cost might be raised as an objection, but the cost per meter is slight, and pays for itself in a short time in water pumped, and wear and tear on the system. Once a meter is installed, it is good for a minimum of 20 years. It might require re- pairing during that time, as any other mechanical apparatus might, but counting repairs, the average life of a meter is perhaps a quarter century. Water is sold by gallon or cubic foot measure. The number of gallons a consumer is entitled to at different rates are given in Table XLI. This table gives the number of gallons of water which a consumer is entitled to use daily for 365 days or one year, for the rate stated in the left hand column, at the price per 1000 gallons given in the heading. TABLE XL. Loss of Head in Meters f Disk Meter, 1 inch stream 10 cubic feet of -water . . .2 minutes, 18 seconds 1 Connection only 10 cubic feet of water. . . 1 minute, 36 seconds I Disk Meter, IJ^ inch stream. . . 10 cubic feet of water ... 1 minute I Connection only 10 cubic feet of water ... 33 seconds ( Disk Meter, 2 inch stream 10 cubic feet of water .. . 40 seconds I Connection only 10 cubic feet of water ... 27 seconds I Disk Meter, 3 inch stream 100 cubic feet of w ater ... 2 minutes, 45 seconds I Connection only 100 cubic feet of water ... 1 minute, 58 seconds f Disk Meter, 4 inch stream 100 cubic feet of water ... 1 minute, 42 seconds Connection only 100 cubic feet of water ... 1 minute . 22 seconds Disk Meter, 6 inch stream 100 cubic feet of water ... 1 minute. 24 seconds , Coimection only 100 cubic feet of water ... 1 minute. 16 seconds The cost of different quantities of water at different rates per 1000 gallons can be found in Table XLII. The table is used in this way : At 5 cents per 1000 gal- lons, 400 cubic feet of water would cost 15 cents, at 6 cents per 1000 gallons, 18 cents ; at 10 cents per 1000 gallons, 30 cents and at 30 cents per 1000 gallons, 90 cents. Digitized by Microsoft® 152 Principles and Practice of Plumbing Waste of Water. — Where water is not sold by meter rates, more water is wasted than is used. It is, of course, not advisable to stint in .the use of water, but when the daily- consumption of water per person runs as high as 150 to 300 TABLE XLI. Water a Consumer is Entitled to Daily at Giv£n Rates No. of No. of No. of No. of No. of No. of No. of No. of No. of gallons gallons gallons gallOins gallons gallons gallons gallons dollars per day per day per day per day per day per day per day per day paid. at 5c at 10c at ISc at 20c at 25c at 30c at 40c at 5Qc annually per 1000 per 1000 per 1000 per 1000 per 1000 per 1000 per IbOO per fOOO gallons gallons gallons gallons gallons gallons gallons gallons $ 1 54.8 27.4 18.2 13.7 10.9 9.1 6.8 5.5 2 109.6 54.8 36.6 27.4 21.9 18.2 13.7 10.9 3 164.4 82.2 54.7 41.1 32.8 27.4 20.5 16.4 4' 219.2 109.6 73.0 54.8 43.8 36.5 27.4 21.9 5 274.0 137.0 91.3 68.5 54.8 45.6 34.2 27.4 6 328.8 164.4 109.6 82.2 65.7 54.8 41.1 32.8 7 383.6 191.8 127.8 95.9 76.7 63.9 47.9 38.3 8 438.4 219.2 146.1 109.7 87.6 73.0 54.8 43.8 9 493.1 246.6 164.4 123.4 98.6 82.2 61.6 49.3 10 547.9 273.9 182.6 137.0 109.6 91.3 68.4 54.8 20 1096 548 365 274 219 182 . 137 109.6 30 1644 822 548 411 329 274 205 164.4 40 2192 1096 730 548 4.38 365 274 219.2 ,50 2740 1370 913 685 548 456 342 274.0 60 3288 1644 1096 822 657 .548 411 328.7 70 3836 1917 1278 959 767 639 479 383.5 80 4384 2191 1461 1095 876 730 548 438.3 90 4931 2465 1643 1232 986 822 616 493.1 100 5479 2739 1826 1369 1095 913 684 547.9 200 10959 5479 3653 2739 2191 1826 1370 1095.8 300 16438 S219 5479 4109 3287 2739 2055 1643.8 400 21918 10959 7305 5479 4383 3652 2740 2191 .7 500 27397 13(;98 9132 6849 5479 4566 3424 2739.7 (100 32S76 16438 1095S 8218 6575 5479 4109 32S7.6 700 3835(i 19178 127S4 958S 7671 6392 4794 3835.6 800 43835 21917 M610 1095S 87 60 7305 5479 4383.5 900 49315 24657 1(U37 12328 9862 S21S 6164 4931.5 1000 54794 27397 lS2():i 13('9S 10959 91,32 6849 ,5479.4 gallons, fully one-sixth of it is wasted. Where water is charged for at the comparatively high rate of 15 cents per 1000 gallons, by meter, this will allow a daily consumption o:^ water in a home of about 220 gallons for an annual tax of Digitized by Microsoft® Principles and Practice of Plumbing 153 TABLE XLII. Cost of Water per 1000 Gallons COST PER 1000 GALLONS of Cu. Feet sets. 6 Cts. sets. 10 Cts. 20 Cts. 25 Cts. 30 Cts. Cost for Quantity Given in First Column 20 $0,007 80.009 $0,012 $0,015 $0,030 $0,037 $0,045 , 40 0.015 0.018 0.024 0.030 0.060 0.075 0.090 60 0.022 0.027 0.036 0.045 0.090 0.112 0.135 80 0.030 0.036 0.048 0.060 0.120 0.150 0.180 100 0.037 0.049 0.060 0.075 0.150 0.187 0.224 200 0.075 0.090 0.120 0.150 0-299 0.374 0.449 300 0.112 0.135 0.180 0.224 0.449 0.561 0.673 400 0.150 0.180 0.239 0.299 0.598 0.748 0.898 500 0.188 0.224 0.299 0.374 0.748 0.935 1.122 600 0.224 0.269 0.359 0.449 0.898 1.122 1.346 700 0.262 0.314 0.419 0.524 1.047 1.309 1.571 800 0.299 0.350 0.479 0.598 1.197 1.466 1.795 900 0.337 0.404 0.539 0.673 1.346 1.683 2.020 1000 0.374 0.449 0.598 0.748 1.496 1.870 2.244 2 000 0.748 0.898 1.197 1.496 2.992 3.740 4.488 3.000 1.122 1.346 1.795 2.244 4.488 5.610 6.732 4.000 1.496 1.795 2.393 2.992 5.984 7.480 8.976 5.000 1.870 2.244 2.992 3.740 7.480 9.350 11.220 6.000 2.244 2.692 3.590 4.488 8.976 11.220 13.464 7 000 2.618 3.141 4.189 5.236 10.472 13.090 15.708 8.000 2.992 3.590 4.787 5.984 11.968 14.961 17.953 9.000 3.366 4.039 5.385 6.732 13.464 16.831 20.197 10.000 3.74 4.488 5.984 7.480 14.961 18.701 22.441 20000 7.48 8.976 11.968 14.961 29.992 37.402 44.882 30.000 11.22 13.46 17.95 22.44 44.88 56.10 67.32 40.000 14.96 17.95 23.94 29.92 59.84* 74.80 89.77 50 000 18.70 22.44 29.92 37.40 74.80 93.50 112.20 60,000 22.44 26.92 35.90 44.88 89.76 112.20 134.64 70,000 26.18 31.41 41.89 52.36 104.72 130.90 157.08 80,000 29.92 35.90 47.87 59.84 119.68 149.61 179.53 90,000 33.66 40.39 53.85 67.32 134.64 168.31 201.97 100,000 37.40 44.88 59.84 74.80 149.01 187.01 224.41 200,000 74.81 89.76 119.68 149.61 299.22 374.02 448.82 300,000 112.20 134.64 179.53 224.41 448.83 561.03 673.24 400,000 149.61 179.53 239.37 299.22 598.44 748.05 897.66 500,000 187.01 224,41 299.22 374.02 748.05 935.06 1122.07 600,000 224.41 269.29 359.06 448.83 897.66 1122.07 1346.49 700,000 261.81 314.18 418.90 523.63 1047.27 1309.08 1570.88 800,000 299.22 359.06 478.75 598.44 1196.88 1496. 10 1795.32 900,000 336.02 403.94 538.59 673.24 1346.49 1683.11 2019.73 1,000,000 374.02 448.83 598.44 748.05 1498.10 1870. 12 2244.15 Digitized by Microsoft® 154 Principles and Practice of Plumbing V -(J 1-9 X pa ^CDi©^0000(NC<»r c^" o g z .s < i-il-^(N(NOS(N-<^'^0000»O 5 ^U5a>(M-*t^OiO(NiOOO tC4 § rH,-lr-lC^(MCq{NCOC0COC0 OOOOOOOOOOO 00(N000000CDCD00O(NO Fh c C003e0-^£N0ii-iT-l00Ot^ rH t^OlWiCI>000^(MiOCD i-HrHi-(i-(^C<|C- 1— I T— 1 I— 1 1-H 1— H 1— 1 rH U K o cDcOOOO°rt<{M.^i-H^(Nl--_^i-H[N o T-T c^" CO co'--^''-rtr lo" Iff >o CO* cxT o fti .s OOOOOOOOOOO CDOOCDCD0005COOIM d) :^ .-r r-T im" (m" (M" CO CO CO CO CO' -^ g < * s _g SSoSSSSSSSS ^ ^^ ^'■'-<' '-<"--<*' '-<'''NCS» (N d OOOOOOOOOOO C0Th(»O<£>':0l-^Gi000050:iO i:^^: d »0 (M lO lO (M lO Tti O lO O O l^ t-H CO lO I- Oi O i-< (N •* l-^ 5 ^^rHT-.T-<[M(N(N(N(M CDNCT>iOi-lOOThH>OCOC:i C4 m cDcooicocoa)cooioo- 06l>!lOrtHC0i-HQ^»OCOr-i rHJNCO'fuOCDOt-OOO 1— 1 •dl (M-*CDX'OC^'er. Fig. 77 the pipe, and the results obtained under those two conditions were very similar. The conditions under which the experiments were made that produced the foregoing diagrams are given in Table XLIV, which shows intensity, duration and number of pressure waves produced in a 1 1/2-inch pipe by suddenly Digitized by Microsoft® 158 Principles and Practice of Plumbing closing a i/ls-inch self-closing basin cock. Approximate time of closing cock 1/100 of a second. The intensity of a high pressure wave caused by sud- denly arresting the momentum of a colunin of water m a 2-inch pipe by shutting a quick-closing gate valve of the full loafer fiommer Diagram: 1^ inch Pipe, Air Chamber. Fig. 78 size of the pipe, is graphically shown by the diagram, Fig. 80. It will be noticed that this diagram records a vacuum of about 15 pounds due to the reflex wave. This is supposed by the experimenters* to be an error. It is believed by them that the momentum of the moving parts of the recording apparatus carried the line that much below l^^ater Hammer Diagram; /pnchPipe, iVafer C/iamber Pig. 79 the line of atmospheric pressure E F, and that likewise it recorded a maximum pressure of 15 pounds in excess of the pressure actually produced. Allowance should therefore be made for the error. A number of experiments were made with the 2-inch •Two sliuk'iits of Cornell College iiuliiig mulor the iliroctioii ot Trotcssor Carpenter. Digitized by Microsoft® Principles and Practice of Plumbing 159 pipe and quick-closing lever-handle gate valve, to determine the intensity of the water hammer under different veloci- ties. Some of the experiments were made with an air chamber of 40 cubic inches capacity, attached to the water pipe near the valve. Some of them were made with an air chamber of 320 cubic inches capacity attached, and still others were made without an air chamber. From the results obtained by the experiments, the diagram. Fig. 81, was plotted. Diagram IVoier Hammer. ^/nchP/pe. JO*S/af/c firessurf. Fig. 80 In this diagram the curves all start at the point of static pressure in the pipe, as that is the initial pressure. The results of the experiments plotted on the diagrams show the high pressure that can be produced in a pipe by abruptly stopping the flow of water, even when the velocity and press- ure are comparatively low. It also shows the value of air TABLE XLIV. Intensity of Water Hammer General Data Static pressure Number of distinct blows . . . Maximum pressure Minimum pressure Time pulsations continue. . . . Pressure at end of one second .Ratio of increase of pressure. . No Air Cliamber Fig. 73 29.5 8. 72.5 2.5 0.8 sec 36. 2.47 Fig. 74 28.5 9. 69.0 16. 1.2 36. 2.56 Air Chamber Fig. 75 27.5 9. 61.5 10. 0:8 31.5 2.15 Air Chamber Filled with Water Fig. 76 28. 9. 76.0 9. 1 . 1 sec. 36. 2.70 Note: Table and diagrams from "Transactions of American Institute of Mechanical Engineers," Vol. XV, page 510. ^ Digitized by Microsoft® 160 Principles and Practice of Plumbing chambers on water supply pipes and the necessity for using slow-closing cocks in practice, particularly when the press- ure of the water is high. With a static pressure of 30 pounds per square inch and a velocity of 8 feet per second, the maximum pressure due to water hammer when no air chamber was used was 320 pounds to the square inch; an increase in pressure of 290 pounds or an ultimate pressure of almost eleven times 3^0 300 280 260 <240 \220 / 2 3 S 7 8 & /O '200 ^/90 '\/20 \/00 \80 ^60 40 20 V ,/ / . « • • > i » • • /• + / / rt f ^^^ V ( f, / <^ A f> /■ f^^ ^ t ' • ftC l'^ / \^^ / w*-* ^ / y ^ y\H , f' ^ A ^^ V Ct r\ '% tr- + / y *^ J> n? (^i ^.ll > y r^ n?g ef J* y' X ^/l 6)1' -^ A /e/oc/f/ in Feet per Seconcf. Fig. 81 riiai't of Wator Hamnior the initial pressure. At a velocity of 4 feet per second with all of the other conditions unchanged, the maximum press- ure was about 135 pounds per square inch, or an ultimate pressure of 40 00 Oi (M CO ■ O 3 M,^;^^ jq ,j3 j3 ^ J3 ,£3 .Scjoouu o o o u Digitized by Microsoft® 172 Principles and Practice of Plumbing Wrought Iron and Steel Pipes. — ^Wrought pipes and steel pipes are made in various sizes and weights and may be had plain, tar coated or galvanized. The weights of wrought pipe are designated as standard, extra strong and double extra strong; standard weight pipe being the weight most commonly used in plumbing installations. Wrought pipe is sometimes classified as butt-welded and lap-welded. In the manufacture of butt-welded pipe the edges of the metal that forms the pipe are butted together and welded. In the manufacture of lap-welded pipe the edges are first beveled and then lapped and welded to smooth interior and exterior finishes. Butt-welded pipes are not as strong in the seam as lap-welded pipes and are made only in small sizes of standard weight. Wrought pipes are galvanized by cleaning them with acid and then immersing them in a bath of molten zinc or tin and zinc. This process makes the pipe a little more brittle than plain pipe, but it lengthens its life by preserv- ing it from corrosion. Furthermore, galvanizing protects the water that flows through the pipe from rust discolora- tion, which would render the water unfit for domestic and for most manufacturing purposes. The safe working pressure for wrought pipe does not depend altogether upon the thickness of the walls of the pipe and the tensile strength of the metal, but is governed by the strength of the seamls and the method of connecting difl'erent lengths of pipe. For instance, a IVg-inch butt- weld standard pipe is tested to a pressure of 600 pounds and will safely sustain a working pressure of 300 pounds to the square inch, while a li/o-inch lap-weld standard pipe is tested to a pressure of 1000 pounds and will safely with- stand a working pressure of 500 pounds per square inch. The rule may be broadly stated that small sizes of standard weight pipe, ranging from Vit to 1 1/2-inch diame- ters, are butt-welded and tested to 600 pounds pressure. Such pipes will safely sustain a working pressure of 300 pounds per square inch. All larger sizes of standard weight pipes are lap-welded. They are tested to 1000 pounds, and will safely sustain a working pressure of 500 Digitized by Microsoft® Principles and Practice of Plumbing m ^looji jad |EU!XIIO]sI o bo s o e o o •I— I X S V s 300^ Diqno 3di^ JO ti'iSuaT; r-GOOO"^Tt<.-H.-H,-l11|-oOGOOOOOOCOOC« I— I i-H i—t .— I 10 CO i> ■<*< (M 1-1 aoEjjns ao^jjng lOlOOOi— l00l>-»Ot^O5CCt^ ■^ O l> - r- r>- TfH T-H 00 00 T-H lo 05 -^ i> t* '^l-*iO"«tiCOOOi-lO(NC5iO-^c£Jo01^- ■^OOiOCC)OCOOcDcSOOiOOI>cC'iO 01 1>- O "^ CO CQ (N C- 03 CO (M l>- Tt< rH-rt4cDC3CNlOOOI>--^OOCOaiTj-c^cc''^coajocsi>-0'^b-i>-i>-i-40o Oi-Hi-HcacO^CDl-^Ot^tMOi-iOCOiO '■-<'.-< ci c^ CO co-^'o CO 1— I 1^ 00 CO o t^THi-H-^COtNcOoOCO-^OOI^ i-i 00 ^OOiOCO^C-OiCOiOOOOOOOCOOOsOO O»-Hi-lC0i000Tta)Oi00 (NlN'OLOcDi-OOcocOCniMOOCOOi-^ .-C(NCOi.Ci00COT-i00'>*f-«:t^MJ».OO3^C0Tt< 1T?U.I31UI |BU.T31Xa Q0-^(Nt^aiCNi«»-i''^C0OO00(N5?'* -^-t4it:)»ooooicococnu:iro'^'«t-CDrHCOi-lCOO i-H.-(i-HC-"icO'^iOcdl>Oi-i(NTH'0 CMcDi-H02C5i-HiO0i.-(C^OcC>r^00t^c0 I-OiiMCOOiCO'-icDOcOOiOCOOt^'-t CMOi— ico(N'— i(NOS"<*OOi>Ot-ir^Tr4c/0 ssauiiDiqx OOOClO'-400-i^'+iOO>-i(NcO-^iO'jO O O O '-I •-H rH .— I ,—1 ,-H C-l (M C^ . t^ CO ^ rH COOt^i"^i>-rH^ 0000»-(iOCi-*l^l-- Osi^iO"*CO(MiMiMr-i.-(.-i a 2 - 1B13H a cOi-iCiCO'^tiOOCOiMiOCOfM lOOO lO Q0c0»-i(M'-l'^C5000i00i0»-H0Tt*(MO Oi-HtMCO'TMCOOOO-^NOt^Tt^lNirHlC "-(i-lC-ICOCO'^iJtJCOOO IBUJ9:^UI c cooooi^ci i-i CO urs Oi lO CO OS i>- CO t^ eOcOCOCOiC»-ib-iO-COOCOiOrfQOOiCO oOi-ic^-^t^iMt^Oicqaioo-^coi-iOi ^'-(Ol'^COOO'-tTtHOOlO IBUja^jxg C: O 00 TJ^ CO 00 Tfi uo CM --h cO -^ lO cO (M (MCOiOOOCOi-IOOTt<-^COiOOSCOCO'* T-H C'l r-1 ^ ;0 Ct' (N lO oi tJH -:J^ g E Ii3uj3:ju]; t th-^cocooiocoo'**< -d^(^^^NO'-loodoi^•>-^*GOTt^oi-^d^cQco c003C0I>C0050iC0O(NOi005"^i-iO .-H.-HC<»rMC0'*c0t^OiO^C0»i500 tH T— 1 tH 1— C 1— 1 |Buja;xg S3 1 c<»cOi--co I>Oi(MC005COT-HCOCOCOO:cOCOOt^'-i (NCOrHOCNT-c(NOS'*OCSU3i-tI>'*00 ^^ .^ r^ -r-i T-t ^ 33nE3 3JIAV 1S3JB3J<[ 6 :st :s^ :s. 's: (N'-'O0SQ0«CC;Ci0(M.-IOC;OOO .-^ T-H T-H O OO SB au^^lMX 1 n i i5 [BUJ3;UI -ixojddv 1 M (M -^ A t~ O: (N ■* o « 00 rf 00 C^ So t2 '^^—'C^KNOSM-^^.O iBuja^jxa IBn^joy 1 S ^ ^ — ,„ "^ ro ""■'5 Q CO >0 ^I'^tOOOOWtOc: COQO.O .oSSS [ BUia^u J iBuimo^si 1 a Digitized by Microsoft® Principles and Practice of Plumbing 175 pounds per square inch. Extra strong lap-welded pipes when joined with- extra heavy couplings will safely sustain a working pressure of 1000 pounds per square inch. Most of the pipe now sold as wrought iron is in fact made of steel. It cannot easily be distinguished from wrought iron pipe, and for most purposes is equally as good. In Tables XLVII, XLVIII and XLIX the weights and dimensions of standard, extra strong and double extra strong pipes can be found. These tables of dimensions and capacity of pipes are from 14 to 6 inches inclusive. Larger sizes are so seldom used by plumbers that they have been omitted. The num- ber of threads to the lineal inch can be found in table of standard wrought pipe. The number of threads is the same in the corresponding sizes of extra strong and double extra strong pipe. Merchant and Full-Weight Pipes. — In addition to the classification of pipes as standard, extra strong and double extra strong, there is a distinction made among man- ufacturers and dealers between pipes which run within 5 per cent, of specified weights and those which fall below the 5 per cent, limit. Pipes which are within 5 per cent, of card weights are kno-\yn as full weight pipes, while those which fall below the 5 per cent, limit are known as merchant pipes. There is no difference in the materials used for the different grades or sizes of pipes, and so far as the full weight and merchant pipes are concerned, they are sub- jected to the same tests and receive equal care and inspec- tion as to welding and material. Merchant pipe is from 2 to 3 per cent, lighter than full weight pipe, and will con- sequently vary as much as 8 per cent, from card weights. However, for most purposes it is sufficiently strong, but when the maximum weights and- strengths are wanted, full- weight pipe should be specified. Brass Pipes Brass pipes of iron-pipe sizes are made in stock lengths of 12 feet, although special lengths can be had to order. The lengths are seamless drawn, can be had plain, polished, Digitized by Microsoft® 176 Principles and Practice of Plumbing bD e e m a Hi G O m e « S Q X I— t h4 1-9 < ?00^ J3Cl lEuimoN ^ -r lO CJ 'X 'IZ irz rX: CO CI t-* i~. •* CD (N -r c ;jd lo I- •# in rt .-H BO So <« o soBpng 1 1— 1 (5; t^ 1-* -^ "^ 00 00 w lO Oi -* t^ l^ rMCOOO'-lO(Mas»O^COOOt-- lOCOOlCOOCOCOOOiOOt-^COiO i < 1 Ie;3h .-H^r-KMT^lOOGOCftr-HlO JEurajui a s — 1 (N ■* >-0 t- C: (M 00 r-! T-l lEUjsixg 1 lOOOCO^OO'^'^COiOOSCOCC"* a |13UJ3:jUI s too-* OO-^coiOcotNlr-^iO CDfN-^OOi-IQOi-it-COiOOOi-i C^COOOI>Tt<00l> CO cooi(ro.-icc>cDcooi<©coot^i-< cofN'-iiMos'^oaifttHt^'ci^oo ^ i-H ^ 1-1 ^ C^ a.n^ d oS 1 + O O O O « c\co\ooH«\j|'\T|'NflO i-H i-H O O O O '-'"^uiS'^'^M^e^tA SSSU^IDIIIX S8 •s OOTt*Tt-tO00i-i>OTtlcD(£i-«*cO»O rt*(NCOCOOOa:«000»-HCOCDCOt^ (M'^iOOOO^t^Nt^.-HiOOQO .-ii-(.-((NC t^ OCD(M 00 OCOOOiCOX to lOOiC^ ^i-ii-i»-ic<)i:v^co-**<'^utiioco ]Eujaijui lEuruio^ 1 ::5^;:^ :5t:i^ ::s ::f^ :?: QJ JS s H r/l P: ») fr> ct ■-1 5h o P5 WI 1/1 S cS wmH != S W !« U> « r/) O «*-! S O ^ bo Oj « g fl ^ I, -o PS e c« r/i P 01 N p. Oi c, pq < 1 CO 00 .— 1 lO to iO -V cj CO o d CO o CO 00 CI 'J* ■ '^^ o o CO ° IN .— 1 o ;^ lO (M :s o ■ oo IN to ::)!: - ^ lO rD& t^ioeo>ot^cs vo »o i^ »n 00 00 t^ ^H M^\Ot^OOW»--lO'*lO(OPOOOlOW Ol\OC^fJ'«-"'H ^'-tOOiO i-( ■* 0\ t* r* fo O O^'iHOt*!^ 00>O'<-i t^'Oooes'H -i^rtO(S(MfO\< ^ 00 0\ O O W)»Ort ■ ■ es r~ o 00 ca ro t^ CM Mu -<" ^' 00 Th tr> IN '-i vJ ■^' T- - lo "* ro lO oi H M cs (^ CO -rh ^ QOOOr- 00 tt rfi ui »0 O t- ■JO^es ^w 5 0i'*0\'« -1 1-1 c«i (N r< 3t- CMtOiOOO VOl^OO'^ 00-* 1-* t^ fO ^ ■ ■ ood Tjt (N w*-i i-i^r »oeM 00t*.HTj0 \0 W T-i ro *0 O ^C " 3\0\0rMrt"1* 3 — rrj I— r/i (*) M ■* t- -H (- -1< M lO 00 - O CN ■ ■ .O-r-K--" ■H tfOOO T*sO i/10> rO TfO'-b-^OOOOfO*OOr^OOOOOO*'f*50'*'*'*'OcMiOf*)00000(NPMr-MtOfO-^'*i--0\TfOO-^ ■^(N-^'00>C^IO'-"^'^00*l-;l>;00(N<^Oi--iCMOO '^*J^S^S -H"^'"cM~oJfO^"-*'0«t-*0'0 00"\0 00"iO H-ro ioi-(f-.»d"^<*i'OOOvooooviofo»qo^^t^f*; "«!?! ^^'(si'cC^lOt^'QOOC^'^t-'O'OPM'lOOl^'or Cd 5 z s: Digitized by Microsoft® 190 Principles and Practice of Plumbing est pipe as a measure. Then: One 2-inch pipe has the capacity of one 2-inch pipe ; one 3-inch pipe has the capacity of 3.06 2-inch pipes; one 4-inch pipe has the capacity of 6.45 2-inch pipes. The combined capacity of the pipes equals that of 10.53 2-inch pipes. Required, a water main with the capacity of 10.53 2-inch pipes. From the table it is found that a 5-inch pipe has the capacity of 11.9 2-inch pipes, so would be more than large enough to serve all the branches. Hotels, clubs, hospitals and other buildings that re- quire an uninterrupted supply of water should when possi- ble be provided with two service pipes. Each service pipe should be of sufficient capacity to supply the entire building and should be con- nected to the street main in different streets. The service pipes should then be cross connected within the building, so that if water is shut off from one city main an ade- quate supply can be Fig. 96 drawn from the Multiple Connection to Street Main other One. Service pipes are usually provided with a stop cock located at the curb. This curb cock gives the water com- pany control of the supply within a building, so that water can be shut off at any time without digging down to the corporation cock or entering the premises. The comparative capacities of pipes of standard sizes, when the velocity of flow remains constant, or the number of times the area of one pipe is contained in that of a larger, can be found in Table LII. Suppose, for instance, it is necessary to know how many times the area of a %-inch pipe is contained in that of a 2V2-inch pipe. Glancing down column 1 to the size marked 21/2, then along the horizontal line until it intersects Digitized by Microsoft® Principles and Practice of Plumbing 191 a, o m 01 > a, S o O >-] -si Eh o ^ Oi 00 1— i T-l l-H r- coco O --H r-« rH (N ^0 CO t^ W t^ rH T-l .-H (>» Ol m "^ CI lO T-l C3 •-< »-l i-HN CO 00 ■* -H .-H C-l CO CO lO CO to coooosO'^ai T-li-itNlMCOiOcOt^ fO CO !> r- 03 (M ^* r- to i-HT-l-ic^COiCOCOO 1—1 ^ OOOi-lOi-i-^COiO '-H^fMN-^cDGOOCOCD .— 1 1— 1 t-i M ^(NOSQCOSCOiOCTiOiO ^^|^»<^^colOQOrH•=:t^oico ^ ;0C0C000l> .-ii-iC^COii:5cdo6coosiOTH(NC^ •-H .-1 (N CO-* to - OrtfCiiOiO-^t^i-irf<030'^CO rHr-l<^^CO^O00r^"*C0CO•i^Q0C0.-l ^ OGOOOClOOOiOOO-^i-iCOOOCOOO <-^r-)(MCOCOCiCOOOCOt^-^^C001l> i-HT-icqc0i0 1-^c35l>-rH ^ 1-4 - t-oasooi>co^i^o i-it-i'M-?t^:O.-i».O-#(NrH»O-*l>'*0DQ0 r-lr-MC^CO-*COCS(MCDOlC !-> --H W (M ." »0 1-- 1-1 OO CO if3 O to CO rfl CO IXM (M r-i lO r-Hr-H0TTfI>Ot^»0tX),-lC0-^O(M.-lC<»rH f-t»-i(NCOiOcDOiOOCOcOT-i >-l rH CC| c^ CO rt^ "■J* 00 as (M i> CO ic (M CO o o CO o >o 1-1 1^ CI trc T-l .-H iri to l^ -^ OS (M ^ 1-1 LTS (M (N t^ (N O -1 1-- i-lr-HCO-tt--OlCMOSI>-t^Q0r-nO w .-1 (N CO ■* CO l> 1" C^COCOCOl^C^lCOcDCOr-lGOiO'^O'MCO^CO rH ,-1 CO >0 C: -f -j:d lO GO CO OS (M (N Ci tO 1-- 00 (M 00 r-i c-l CO lO 00 1- rH o i-Hi-CiMCOtOOOOi-HCO 1—1 T-H i^ Digitized by Microsoft® 192 Principles and Practice of Plumbing the column headed %, it will be seen that a 2i/^-inch pipe is equal in area to nine % pipes. Sizes of Water Pipes. — Water supply systems should be so proportioned that a plentiful supply of water at low velocity can be had at all fixtures. If pipes are too small, there will be the annoyance of one faucet robbing another, also, owing to the high velocity of flow when water is being drawn, a disagreeable singing or hissing noise will be heard in the pipes and the sound will be conveyed to all parts of the building where there are pipes. In proportioning a water supply system the chief condi- tion to be ascertained is the probable number of fixtures at which water will simultaneously be drawn. In resi- dences and other buildings with comparatively few fixtures the supply pipes should be proportioned to supply all the fixtures simultaneously. In hotels, apartment houses and like buildings, however, such provision is unnecessary. It is not probable that more than one fixture at a time will be in use in a bath room, nor is it probable that more than one fixture at a time will be used in the kitchen, although it is quite probable that fixtures in kitchen and bath room will be simultaneously used ; hence, if provision be made to sup- ply at the same time one fixture in each group within a building, the pipes will be of sufficient capacity to meet all requirements. The largest pipe used to supply any fixture is %-inch diameter and the average size i^-inch in diameter. Faucets and cocks for %-inch pipes seldom have an unobstructed waterway larger than 1/2-inch diameter, while the water- way of 1/2-inch cocks and faucets seldom exceeds % inch in diameter ; hence, if in all water pipes an allowance is made of the capacity of a i/o-inch pipe for one fixture in each group, the system will be so proportioned that an adequate supply of water at low velocity will be had at all fixtures. An exception to the foregoing statements must be made in the case of public toilet rooms and batteries of wash basins in factories or other institutions. All the fixtures in such batteries might be used at the same time and an allowance Digitized by Microsoft® Principles and Practice of Plumbing 193 of the capacity of a i/^-inch pipe for each fixture should be made. Example — ^What size of water main will be required lor an apartment house of fifteen families, each family being provided with bath room and kitchen? Solution — Fifteen bath rooms and fifteen kitchens equal thirty groups of fixtures to be supplied at once, and allowing the capacity of a %-inch pipe for each group of fixtures requires a pipe with a capacity of thirty %-inch pipes. From Table LI will be found that a 2-inch standard pipe has the required capacity. Example II — What size of service pipe will be required to supply a hotel equipped with 280 bath rooms and 20 other groups of fixtures? Solution — 280 + 20 := 300, and according to Table LI about a 4%-inch pipe would equal in capacity three hundred %-inch pipes. Water Required for Various Purposes. — The follow- ing information will be found helpful when determining the daily consumption of water for a building: In estimating the demand for swimming pools, it is usually figured to fill pool in 24 hours and to refilter all water in pool once every 24 hours. A pool for 100 persons has a capacity of about 50,000 gallons. For sprinkling 100 square feet of lawn, about 1 cubic foot, or 7 to 8 gallons. For soaking 100 square feet of lawn, about 21/^ cubic feet, or from 15 to 16 gallons. To flush closet each time, 5 to 6 gallons. The actual rate of discharge from water closets is about I14 gallons per sec- ond. To fill the lavatory ordinary, about IV2 gallons. To fill bath tub ordinary, about 20 gallons. The consumption of water by farm animals varies greatly, depending upon the season of the year, the age and the individual habits of the animal, and local conditions. The following table will give a good idea, however : Horse, 5 to 10 gallons per day ; cattle, 7 to 12 gallons per day ; hogs, 11/2 to 21/2 gallons per days; sheep, 1 to 2 gallons per day. For mixing concrete 40 pounds of water are required for each 100 pounds of cement. Forty pounds of water equals 4.82 gallons. The amount of water required for boiler feeding can be found in Table LIII. Digitized by Microsoft® 194 Principles and Practice of Plumbing TABLE LIII. Water Required per Minute to Feed Boilers (Using the "Centennial Standard"— 30 pounds or 3.6 gallons of water per horse power per hour, evaporated from lOOo F. to 70 pounds steam pressure per square inch.) H. P. Boiler Feed Water Gallons H. P. Boiler Feed Water Gallons H. P. Boiler Feed Water Gallons H. P. Boiler Feed Water Gallons H. P. Boiler Feed Water Gallons 20 25 30 35 40 45 50 55 1.2 1.5 1.8 2.1 2.4 2.7 3.0 3.3 60 65 70 75 80 85 90 100 3.6 3.9 4.2 4.5 4.8 5.1 5.4 6.0 110 120 130 140 150 160 170 180 6.6 7.2 7.8 8.4 9.0 9.6 10.2 10.8 190 200 225 250 275 300 325 350 11.4 12.0 13.5 15.0 16.5 18.0 19.5 21.0 400 450 500 600 700 800 900 1000 24.0 27.0 30.0 36.0 42.0 48.0 54.0 60.0 Forty to 60 pounds of condensing water are required for each pound of steam condensed to moderate temper- ature. Sixty to 100 pounds of water per pound of steam when the water used is at the higher temperature common to cooling tower practice. Consumption of water in mili- tary camp is about 10 gallons per capita daily. TABLE LIV. Flow of Water at Plumbing Fixtures* Kind of Fixtures Ifltchen Sink Bibb Pantry Sink, High Goose Neck Cocks Pantry Sink, Large Plain Bibbs Vegetable Sink Bibbs Laundry Tray Bibbs Sloi) Sink Bibbs Basin Cooks Bath Cock, (either hot or cold) Shampoo Spray Liver Spray Shower Baths, 5-inch Rain Heads Shower Baths, 6J4-infih Rain Heads.. Shower Baths, 8-inch Rain Heads.. . . 8-inch Tubular Shower Heads Needle Baths Maniciu'e Tables Fair Flow Gallons Per Minute '2 1 2 2 4 (■) 20 1 Good Flow Gallons Per Minute 4 6 4 3 4 1 2 3 3 6 8 30 11' Excellent Flow Gallons Per Minute 6 4 *) 2 3 4 5 8 10 40 2- •Speakmaa. Digitized by Microsoft® Principles and Practice of Plumbing 195 Water flows from an ordinary kitchen faucet at the rate of about 3 gallons per minute in average use. The range of flow at fixtures of different kinds under a pressure of 30 pounds per square inch can be found in Table LIV. Digitized by Microsoft® 196 Principles and Practice of Plumbing CHAPTER XXI PUMPS AND PUMPING Lift or Suction Pumps Principles of Operation. — The operation of a suction pump is dependent on and its efficiency limited by atmos- pheric pressure. If there were no atmospheric pressure there could be no suction lift to a pump. This is shown by a reference to the suction pump, Fig. 97, which consists of a piston, a, in a pump barrel or cylinder, b, a valve, c, that opens on the down stroke of the piston and closes on the up stroke, and a valve, d, that opens on the up stroke of the piston and closes on the down stroke. The operation of the pump is as follows : When the piston, a, makes an up stroke it exhausts some air from the suction pipe, e, and a sufficient quantity of water flows in to replace the exhausted air and balance the atmospheric pressure on the water outside. On the down stroke of the piston the exhausted air which has been confined in the pump cylinder escapes through the valve, c, which opens on the down stroke. The next up stroke of the piston still further exhausts air from the suc- tion pipe and a still higher column of water flows in to replace the exhausted air. Repeated strokes of the piston exhaust all air from the suction pipe and pump cylinder, which then fill with water which is pumped out as was the air. Lift of a Pump. — Theoretically a pump will raise water a distance equal to the height that atmospheric press- ure will balance a column of water in a perfect vacuum. Experience and experiment, however, have demonstrated that a pump will raise water only about .75 of the theo- retical height. This difference between the theoretical and the actual lift of a pump is due to the loss of head caused by friction in the pipe, and the impossibility of securing a per- fect vacuum on account of mechanical imperfections in the pump and connections, air in the water and vaporization of the water itself. The constant .75 holds true, however, only Digitized by Microsoft® Principled and Practice of Plumbing i^l for water at ordinary temperatures. Any appreciable raise in the temperature of water will eause a eorregponding loss of lift. This is due to the faat that in a vaeuum water vaporizes at a lower temperature than when under pressure, and when air is exhausted from the suction pipe of a pump connected with a hot water tank or receiver, the water instantly flashes into vapor and fills the suction pipe, pre- venting the formation of a vacuum. Water of temperatures higher than 180 degrees Fahrenheit cannot successfully be raised by suction but for the best operation must flow into a pump by gravity. Waters of lower temperatures but over 100 de- grees Fahrenheit are much easier handled when they flow by grav- ity into the pump cylinder. Atmospheric pressure varies with the elevation, that is, the dis- tance above or the depth below sea level ; hence on the side or top of a mountain the atmospheric pressure and consequently the lift of a pump will be less than at the sea level. Also, the atmos- pheric pressure and lift of a pump in a deep pit or mine will be greater than at sea level. The atmospheric pressure at sea level varies with the conditions of weather, but for practical purposes is taken as 14.7 pounds per square inch, and as 1 pound pressure will bal- ance a column of water 2.309 feet high, it follows that in a perfect vacuum atmospheric pressure should balance a col- umn of water 14.7 X 2.309 = 33.95 feet high. Atmospheric pressure at different altitudes with equivalent head of water and the vertical suction lift of pumps can be found in Table LV. In addition to the vertical lift, a suction pump will draw water horizontally a great distance; nevertheless, when water must be conveyed any great distance, better Pig.' 97. Suction Pump Digitized by Microsoft® 198 Principles and Practice of Plumbing results are obtained by using a force pump and placing it close to the source of supply. Force Pumps. — Suction pumps are limited in the height to which they can deliver water by the atmospheric pressure at the elevation where they are installed ; further-* more, they cannot be used to circulate water through a closed circuit. Hence, when water must be elevated a con- siderable distance through closed pipes, as, for instance, in filling a house tank, a force pump must be used. TABLE LV. Safe Suction Lifts of Pumps Atmos- Temperature of Water Raised Elevation pheric Pressure Baro- metric Degrees Fahrenheit Above Sea Level Per Inches 60 90 120 ISO 180 Square Inch Mercury Safe Suction Head for Pump (Feet) 10,000 10. 107 20.582 17.0 16.4 14.7 11.3 4.7 5,000 12.224 24.890 20.5 19.9 18.2 14.8 8.2 4,000 12.689 25.837 21.5 20.9 19.2 15.8 9.2 3,000 13.169 26.813 22 4 21.8 20.2 16.8 10.2 2,000 13.665 27.824 23.2 22.6 21.0 17.6 11.0 1,000 14.174 28.861 24.1 23.5 21.9 18.5 11.9 Sea level 14.696 29.925 25.0 24.4 22.8 19.4 12. S Lbs. per Sq. In. .255 .693 1.68E 3.706 7.500 Tension of water vapor at Various temperatures Inches mercury .518 1.410 3.427 7.547 15.272 A simple hand force pump is shown in Fig. 98. It combines the functions of a lift pump with that of a force pump. Water is raised to the cylinder by suction as in a lift pump, but when the solid piston, a, descends, the con- fined water cannot escape to the top of the piston, as in the case of a suction pump, but is forced out through the valve, b, to the house tank or other place of storage. This pump is known as a single stroke pump, as it lifts and forces with each alternate stroke of the piston. Slip.— At the end of the up stroke of the piston, the moment when it begins a down stroke, there is a brief in- terval of time during which both valves b and c are open, Digitized by Microsoft® Principles and Practice of Plumbing 199 and during that time water flows back to the source of sup- ply. This back flow of water is known as the slip of a pump. It increases with the height of the lift of the suc- tion, the height to which the water is forced and the slow- ness of the valves in seating. When the vertical lift of a pump is small but the suction is long and the pump forces against a low head, the momentum of the moving column of water sometimes carries it forward while both valves are open ; such a flow is known as the negative slip of a pump. The slip of a pump is a limiting factor in its capacity ; when the slip is great the capacity of a pump will be correspond- ingly decreased, and when the negative slip is great the capacity of the pump will be greatly increased over its theoretical capac- ity. Air Chambers. — When a force pump is operated it alternately sets in motion and brings to rest the en- tire moving column of water. As water is prac- tically incompressible, the sudden starting and stop- ping of the column will cause water hammer that is both annoying to occu- pants of a house as well as damaging to the pump and pipes. This water hammer can be practically overcome by using an air chamber on the discharge pipe and so locating the air chamber that it will remain full of air and receive the initial impulse of the water. An air chamber not only prevents water hammer, but also equalizes the flow between strokes of the piston. When pumps are operating under high pressures the air is soon absorbed from the air chambers, which are thus rendered useless unless some means are provided for re- Fig. Force Pump Digitized by Microsoft® 200 Principles and Practice of Plumbing charging them. A simple contrivance for charging air chambers of steam pumps is shown in Fig. 99. The air chamber and water cylinder of a pump are connected together through a gate valve, a, pipe, b, and a check valve, c, which opens towards the air chamber. Another check valve, d, that opens towards the pump is screwed to the pipe as shown. The standpipe, b, stands partly full of water. Then with the valve, a, properly throttled, when the water piston, e, makes a stroke to the left, some of the water will be drawn into the cylinder, and air will enter check valve, d, to take its place. On the reverse stroke of the piston, water is forced into the pipe, b, and as the confined air cannot escape through the check valve, d, it is forced into the air chamber, thus keep- ing it charged. Single Direct- Acting Steam Pumps. — The type of steam pump most commonly used for house pumps is a single direct-acting pump shown in Fig. 100. The operation of the pump is as follows: Steam enters the cylin- der, a, from the steam chest, b, through the port, c, and pushes the piston, d, to the left, the steam exhausting from the left side of the piston through the port, e, and exhaust, /, to the atmosphere. When the piston has almost reached the end of its stroke, the arm, g, link, h, and rod, i, reverse the auxiliary piston, j, and slide valve, k, so that steam is now admitted to the left side of the piston through port, e, and as the piston travels to the right the exhause steam escapes through port, c, and exhaust, /, to the atmosphere. The Fig. aa Air Cbamber on Pump Digitized by Microsoft® Principles and Practice of Plumbing 201 reciprocating motion of the steam piston is transmitted to the pump piston, I, in the water end of the pump by means of the piston rod, m, to which it is direct connected. Then, as the pump piston travels to the left, water flows through the suction valve, n, into the pump cylinder, while the water to the left side of the piston is forced through the valve, o, into the discharge pipe. On the reverse stroke of the pis- ton, water flows through the suction valve, p, into the pump cylinder, while water on the right side of the piston is forced out through discharge valve, q, into the discharge pipe. An air chamber, r, on top of the valve chamber re- duces shock from water hammer and promotes steady flow. Two drip cocks, s s, serve to drain water of condensation. Fig. 100 Steam Pump from the steam cylinder and a lubricator, t, oils the working parts in the steam chest. This pump is known as a double stroke pump, as it both lifts and forces with each stroke of the piston. For low pressure service the piston in the water end of a pump may be packed with a fibrous packing ; for high pressure service, however, the packing should be of metal. HoKSEPOWER OF PuMPS. — The horsepower necessary to elevate water to a given height can be found by multiplying the weight of water in pounds elevated per minute by the height in feet, and dividing the product by 33,000. An Digitized by Microsoft® 202 Principles and Practice of Plumbing allowance or deduction of 25% from the theoretical horse- power should be made to allow for the loss due to friction, when the runs are not long. If the discharge pipe is long, or contains many bends and branches, the frictional resist- ance of the pipe and fittings should be calculated. Capacity of Pumps. — The diameter of cylinder for a single-acting pump required to deliver a certain quantity of water per minute can be found by the formula : V.i -, in which 1 = length of stroke in feet, g:= number of gallons ) .034 1 n to be delivered per minute, n = number of strokes per minute, d = diam- eter of pump in inches. Example — What diameter of pump plunger will be required to discharge 114 gallons of water per minute; speed of pump, 90 strokes; length of stroke, 1 foot? Solution — Substituting values given in the example. 'He , =: 6.1 inch diameter. — ^Ans. '.034X1X90 When the diameter of a cylinder and the length of piston travel per minute are known, the quantity of water a pump will discharge can be found by the formula : q = 1 a 8, in which q = cubic feet of water delivered per minute, 1 = length of stroke in feet, a = area of piston or plunger in feet, s = number of strokes per minute. Example — ^What will be the discharge in cubic feet per minute from a single direct-acting pump with water piston 6 inches in diameter and length of stroke 8 inches, when running at a speed of 30 strokes per minute? Solution — The area of a 6-inch piston is .2 square foot. An 8-inch piston stroke equals .666 foot. Then, .666 X 30 X -2 =3.99 cubic feet of water per minute. — Ans. Actual Performance of House Pump. — The Union Central Office Building, Cincinnati, Ohio, is 30 stories tall. To pump water to the house tanks located on the 18th and 30th floors, there are two Fairbanks-Morse house pumps, size 12 X 7 xl2 and 18 x 7 x 12 inches. Only one is in ser- vice at a time, the other being kept in reserve, and the two are used on alternate days. An average of 680 cubic feet of water was pumped from the engine room service tank per hour to the tank on the 30th floor, which is about 434 feet above the floor of the engine room. Digitized by Microsoft® Principles and Practice of Plumbing 203 The steam required per hour to pump the water was 461 pounds, or 1.47 cubic feet of water pumped with 1 pound of steam. The eight-hour test indicated that $0,477 in fuel was consumed to maintain and operate the house pump. To pump 1000 gallons of water took 90.7 pounds of steam, and 9.96 pounds of coal, making the cost of coal $0.010906. OuHet B'ig. 101 Screw Pump QuiMBY Screw Pump. — Electrically driven centrifugal or rotary pumps are extensively used in connection with domestic water supplies to raise water to the house tank. One type of electrically driven pump is the Quimby Screw Pump, shown in Fig. 101. This type of pump is suited principally to forcing water and not to raise it by suction ; hence to operate successfully it should be set at such a level that water will flow into it by gravity. When water does not flow to the pump by gravity, the suction pipe should be made short and straight as possible, and should be provided with a foot valve. The four screws that act as pistons in propelling the water are mounted in pairs on parallel shafts and are so arranged that in each pair the thread of one screw projects to the bottom of the space between the threads of the opposite screws. The pump cylinder fits the perimeters of the threads closely without actual contact, and the faces of the intermeshing threads make a close run- ning fit without bearing on and wearing the face of the screws. There is no end thrust on the screws in their bear- Digitized by Microsoft® 204 Principles and Practice of Plumbing ings, because the back pressure of the column of liquid is delivered to the middle of the cylinder and the endwise pressure upon the screws in one direction is exactly counter- balanced by a like pressure in the opposite direction. The suction opens into a chamber underneath the pump cylinder and the liquid passes through this chamber to the two ends of the cylinder, and is forced from the two ends towards the center by the action of the two intermeshing pair of threads, and thence out through the discharge port to the house tank. The power to drive the pump is applied to the main shaft, a, and part of it is transmitted to the aux- iliary shaft, b, by the gears, c. Pumps for house ser- vice are usually fitted up to work automatically. The manner of so connect- ing a Quimby Pump is shown in Fig. 102. The pump is operated by a direct connected electric motor that is controlled by a weighted float in the house tank. When water in the tank is low, the Fig. 102 Automatic Starter for Pump weighted float raises the chain and counterweight, a, until the disk, b, trips the switch lever, c, throwing the contact bar, d, over, as shown by dotted lines, to close the circuit and turn the electric current on to the motor. Then, as the tank fills with water, the float raises and the counter- weight pulls down on the chain until the upper disk trips the lever, c, thus breaking the circuit and shutting off current from the motor. By adjusting the two disks the Digitized by Microsoft® Principles and Practice of Plumbing 205 pump can be made to operate under the slightest loss of head in the tank, but it is better to so place the disks that they will close the switch when the tank is almost empty and open it when the tank is full. This avoids frequently starting and stopping the pump and insures a frequent change of water in the tank. Screw pumps run at speeds ranging from 900 to 1,400 revolutions per minute, according to their size and the service under which they operate. Direct current 110, 220 or 500-volt motors of General Electric, Crocker-Wheeler or Sprague types, are found satisfactory for this work. Electrically driven pumps of the plunger type are some- times used for house service pumps. Pumps qf this type, however, should be provided with a rheostat or starting box to turn the current on to the motor gradually. If the full current were turned on instantly the armature would prob- ably be burned out ; also the pounding due to suddenly start- ing in motion a large column of water might injure some of the more delicate working parts of the pump. Motors for pumps operating under a variable load should be compound wound. Those operating under a con- stant load, should be shunt wound. A series-wound motor when the load is removed is liable to run away or wild. Slow operating pumps that are direct connected should have slow speed motors. For high speed pumps, also for gear connected pumps, high speed motors may be used. Hot Air Pumping Engines. — Hot Air Pumping En- gines are used for supplying water to country or suburban residences, and in tall apartment houses to pump water from the service pipe to the house tank on the roof. This type of pump can be operated by any kind of fuel and re- quires no skilled help to run it. In suburban localities, where a hydraulic ram or a windmill would not be practica- ble, a hot air pumping engine will prove the next least ex- pensive to operate. Suction Tanks. — If large steam pumps, such as are used for fire pumps and large electric pumps such as are used to fill house tanks on tall buildings, were allowed to pump water direct from the city mains, they would causae Digitized by Microsoft® 206 Principles and Practice of Plumbing considerable annoyance while operating by reducing the pressure and thus decreasing the flow of water in other supply systems in the neighborhood. Furthermore, the operation of the pump might cause water ram in the mains that would be annoying to other water consumers and dam- aging to the water supply system. For these reasons, also to store a supply of water on the premises to provide against shortage should water be temporarily shut off from the street mains, suction tanks should be provided in all large buildings. Suctions tanks usually consist of an open steel tank covered with steel or wooden planking. Sometimes, how- ever, they are enclosed rectangular steel tanks with a man- hole and hinged cover, through which access may be had to the interior of the tank. The supply pipe to suction tanks is generally so large that an ordinary ball cock of the full calibre of the pipe would be subjected to too severe a strain, hence large sizes of supply pipes are usually provided with a Ford balanced ball cock. Suction pipes from suction tanks to house pumps are usually cross-connected to the street supply, so in case of emergency, as for instance during a fire, water can be pumped direct from the city mains. Suction tanks should have sufficient capacity to store at least one day's supply of water for the entire building; when space permits, it is better to provide capacity for two days' storage. This quantity will tide over any probable period of time that water will be shut off from the street mains. House Tanks. — House tanks are used to store water for the supply of buildings and should be located at least ten feet above the level of the highest fixture to be supplied. There are two kinds of tanks commonly used, wooden and iron tanks. When located outside of buildings on roofs or in other exposed positions, wooden tanks are generally used ; when located inside of buildings, iron tanks are generally used. During warm weather moisture condenses on the outside of iron tanks, and if not cared for will drip to the floor and wet both floor and ceiling below. To prevent this a drip pan should be placed under all iron tanks and a drip Digitized by Microsoft® Principles and Practice of Plumbing 207 pipe from the pan extended to some convenient sink or con- nected to the overflow pipe from the tank. Lead-lined wooden tanks were formerly extensively used, and in some localities are still, to a limited extent, but owing to the liability of carbonates or sulphates of lead being dissolved from the lining and poisoning the water, lead should not be used for tank linings, particularly in localities where the water is soft. Copper-lined wooden tanks are sometimes used. From a chemical standpoint, copper linings are not so objection- able as lead, particularly when the copper is tinned; how- ever, copper linings present so many joints and seams that some of them are liable to leak, and, in some waters, soldered copper joints rapidly disintegrate, owing either to a chem- ical or galvanic action of the metals. In extremely tall buildings, fixtures on the lower floors are supplied with water direct from the street mains; the upper floors are supplied with water from the house tank on the roof, and intermediate tanks are installed, so that not more than eight floors of the building are supplied with water from any one tank. In such installations the house supply from the roof tank should be cross-connected to the house supply from all the intermediate tanks and to the house supply for the lower floors, so that in case of necessity the entire building can be supplied with water from the house tank, which can be filled by pumping from the suction tank. Storage tanks should be provided with overflow pipes of sufficient capacity to safely carry off the greatest quantity of water likely to be discharged by the supply pipe. It is a safe rule to allow for the overflow pipe twice the diameter or four times the sectional area of the supply pipe. Over- flow pipes from tanks located on roofs of buildings may discharge onto the roof. Overflow pipes from tanks located inside of buildings should discharge into a prope^y trapped and water-supplied sink or a sump in the basement. Under no circumstances should they be connected direct to the drainage system. The size of storage tanks depends upon the number of Digitized by Microsoft® 208 Principles and Practice of Plumbing people to be supplied, and the length of time they are to supply water without being replenished. They should have sufficient storage capacity for at least one day's supply, to tide over possible periods of breakdown of pump or boiler. When figuring the capacity of storage tanks, 100 gallons of water per day per capita should be allowed in hotels, hos- pitals, apartment houses and public institutions. In large office buildings many stories in height, also large hotel buildings, the tanks must be sufficiently large to supply water for the greatest period of time the water is likely to be shut off from the mains. In large important buildings of such character, it is advisable to have as many as three, and four if possible, separate service pipes con- nected to mains in the different streets. This is quite possi- ble when the building fronts on three or four streets, and it might be accepted as a rule to run a service pipe from the water main in every street on which a building fronts. It is not likely that water will be shut off from all the streets at one time, and the possibility of interrupted service be- comes less the greater the number of service pipes provided. Under such conditions smaller tanks can be used than when the supply is from one or two streets only. When there is only one or two service pipes for a building housing a large number of people, and where interruption of water service is not to be permitted, there ought to be storage capacity on the premises for at least 48 hours supply of water. It is not likely that water service in the street mains will be interrupted for a longer period than that. Part of the house supply can be carried in the house tanks, and the rest in the suction tank. The sizes of the tanks can then be proportioned to one another to suit condi- tions, so long as there is 48 hours supply of water available. For instance, if space would not permit the installation of large service or house tanks, the difference would have to be made up in the suction tank; while, on the other hand, if there was but little space for the suction tank, the house tanks would have to be large enough to care for the rest of the emergency supply. The general arrangement of pipe connections to a house Digitized by Microsoft® Principles and Practice of Plumbing 209 tank is shown in Fig. 103. The cleanout or emptying pipe is valved and connected to the overflow pipe. The house supply extends a few inches above the bottom of the tank to prevent sediment entering the pipe. Below the valve that controls the house supply is connected a vent pipe to admit air to the house supply and permit it to empty when the valve is shut off. A vapor or relief pipe from the high- est point in the hot water supply system bends over the tank and thus permits the escape of steam. The pump may discharge into the house tank in the manner indicated when the pump is not controlled automatically. When it is, the pump pipe should enter the tank through the bottom and be controlled by a bal- anced float valve. W/y^. O p^f'^^ A drip pan, a, un- I Lj Llli der the tank and extending a few inches on all sides of it, catches the water of condensa- tion and discharges it through the waste pipe, b, into the overflow pipe. When a tank is supplied with wa- ter by a pump that is not automatic in operation, a tell-tale pipe should be run from a point in the tank about two inches below the level of the overflow pipe to the engineer's sink. Water flowing through the pipe then notifies the engineer when the tank is full. In all tall buildings the hot water line should have a relief valve at the house tank, otherwise hot water will flow from the relief pipe into the house tank. Owing to the water in the cold water down riser being heavier than the water in the hot water riser, the hot water will rise above the level of the water in the house tank. Complete Mechanical Equipment. — An illustration Fig. 103 House Tank Digitized by Microsoft® 210 Principles and Practice of Plumbing of the complete mechanical equipment of a water supply system in a building supplied with street and tank pressure is shown in Fig. 104. Two separate water service pipes from mains in different streets are cross-connected before being connected to the meter, so that water from either or both street mains can be used. The meter is shown by- passed. Some water supply companies will not permit a by-pass around a meter, and where such a rule prevails another meter should be placed on the by-pass. From the meters the water passes to the filters, which are so con- f/rePunyi- Sttefion Tank. -■H 4. ij — — I Fig. 104 Mechanical Installation =6=-.^ fromSfrgelMo/n nected that they may be used either separately or together. A by-pass is provided around the filters, so water can be supplied direct to the building without filtration. After leaving the filters, one branch of the house main is connected to the cold water main for the lower floors, another branch supplies the hot water tank for the lower floors, still an- other branch supplies the suction tank through a balanced ball cock, and the remaining two br'anches are connected to the suction pipes of the two pumps, so they can pump direct f rem the city water mains. The pumps are also connected Digitized by Microsoft® Principles and Practice of Plumbing 211' by suction pipes to the suction tank from which they gen- erally draw water. The supply pipe from the house tank is connected to the supply pipe from the street, at a point between the two cold water drums. A valve is there pro- vided so that in case of necessity water from the house tank can be turned on to the lower water supply system. A check valve is placed where marked on the illustration, to prevent water from the house tank running off into the street mains or returning to the suction tank. Digitized by Microsoft® 212 Principles and Practice of Plumbing CHAPTER XXII FIRE LINES System of Installation. — Fire lines are now gen- erally installed in all large buildings. A typical arrange- ment of pipes for fire service is shown in Fig. 105. In this system the lines are cross-connected, so that either the fire pump, the house pump, or both pumps can supply water in case of fire. A house tank on the roof keeps the lines full of water and provides a temporary supply while the pumps are being started. Branch lines extending through the building walls to the street terminate with Siamese twin connections, through which water from street hydrants or fire engines can be forced into the system. The fire system is well supplied with soft seat check valves, so that water supplied from one source cannot be lost through other out- lets. A check valve in the line of pipe connected to the tank prevents water from filling and overflowing the tank when supplied from pumps or twin connections. Checks in the lines leading to the twin connections prevent the loss of water from these outlets when water is supplied from either the pump or the tank, and check valves in the pump pipe re- lieve the pump valves of the pressure of water in the system. Emptying pipes are provided to drain the entire system, and separate pipes are provided to empty and thus prevent water freezing in the portions of pipe between the check valves in the cellar and Siamese twin connections in the street. At each floor of the building 2y2-inch outlets are left, to which are attached soft seat angle hose valves with 50 to 75 feet of underwriters' linen hose coiled on a reel or folded on a rack. Sizes of Standpipes. — For fire lines standpipes should be proportioned to the number of hose outlets they supply. The size of opening in hose nozzle for hose of 21/^ inches diameter seldom exceeds IVi inches in diameter, and if Digitized by Microsoft® Principles and Practice of Plumbing 213 allowance of the sectional area of a 2-inch pipe be made for each hose outlet in the building, both sufficient volume and pressure will be provided to throw an. effective fire stream when all the nozzles are being used. Fig. 105 Fire Lines Range of Fire Streams. — The extreme distance water can be thrown both horizontally and vertically, and the distance the streams will be effective for fire purposes under different heads and through different sizes of nozzles, are shown in Table LVI. Digitized by Microsoft® 214 Principles and Practice of Plumbing o 3 u- O o C3 . 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C:00 t^ CD '^ t-lt^ CO t> (N iCi CT" (N -f O 00 lOOirtOiOQi^Oi-OOiOOiOQ CC-i^t000D 03050 00 CDrt< T-H (M C.00 Oi O ■^ CDOOOC^'O .-H i-H i-H N CS C^ Ot^'^'-HOOiOtMOSCD C^COOt-OOOtMcOiO OiOlNCO'*CDI>000»-i(N"*iO (MOOCOCDOICI'^CDOOOCI^O :D :D t - 1-- l-^ t^ 'X; 00 00 00 OS Gi Oi OS O CO tO CD CO »0 CC O !>• -^ 03 >f5 O ^ -+iOOOOC^"^COCCOiT-H(M'*cDI>- C0C0;O^'^rt00>OC CO-^-^i-CiftCSCCM-^t^OOOOOlOK 0) V q; V Digitized by Microsoft© Principles and Practice of Plumbing 217 Fig. lOG Siamese Twin Connection Siamese Twin Connections. — A Siamese Twin Con- nection is shown in Fig. 106. A flap valve, a, closes one opening when pressure is applied to the other, and stands open as shown in the illustration when water is being forced throught both openings. Fire Hose. — A very convenient hose for use in short lengths in buildings is underwrit- ers' linen hose. It will withstand almost any pressure likely to be subjected to and, being flexible, can be neatly coiled or folded into a very small space. The size of hose generally used for this pur- pose is 214 inches diameter. For lengths of more than 25 feet, for real fire fighting, a smooth rub- ber-lined hose is the best to use, and in no case should the hose be less than 2V^ inches in diameter, if it is 50 feet or longer, for a smaller hose will have only about one-half the effective range. For instance, with 80 pounds pressure, 250 feet of 214-inch unlined linen hose will have an effective height of stream of 42 feet, while under the same pressure, and with the same length, a 2-inch unlined linen hose will have an effective height of only 20 feet. The superiority of smooth- lined hose over rough linen hose, for fire protection, also the loss in range due to friction in long lengths of hose can be judged from the following statement based on experiments, where the static pressure was 80 pounds, and pressure at the hydrant when the hose was playing, 70 pounds per square inch. With a 1%-inch nozzle, the heights of effective fire streams were : Fig. 107 Hose Reel Digitized by Microsoft® 2l8 Principles and Practice of Plumbing With 50 feet of 2Va-inch linen hose 73 feet With 250 feet of 21/2-inch linen hose 42 feet With 500 feet of 21/2-inch linen hose 27 feet With 50 feet of best and smoothest 214-inch rubber lined hose 81 feet With 250 feet of best and smoothest 21/2-inch rubber lined hose 61 feet With 500 feet of best and smoothest 21/2-inch rubber lined hose 46 feet This shows the importance of having fire lines suffi- ciently large to maintain a high pressure and supply a large volume of water when all the outlets are in use, and having the fire lines at such points that long lines of hose will not be required. Hose Reels. — Each length of hose should be neatly folded or coiled on a rack or hose reel provided for that pur- pose and attached to the wall or fire pipes close to the valve outlet. A swing hose reel is shown in Fig. 107. It is sup- ported from the fire stand-pipe by a hinged clamp that per- mits the reel to turn in many directions. A li/g-inch smooth nozzle is the best to use in connection with fire lines. Digitized by Microsoft® Principles and Practice of Plumbing 2ld PART III PURIFICATION OF WATERS CHAPTER XXIII FILTRATION Rapid Sand Filtration Theory of Filtration. — ^Water for municipal supply may be classed, according to the source from which it is obtained, as surface water or as ground water. Waters obtained from streams, rivers, lakes, or impounding reser- voirs are surface waters; generally such waters are soft, and when filtered are the best kind of waters for both domestic and for industrial purposes. As surface water exists in nature, however, it is never organically pure and seldom clear; it generally carries considerable matter both in suspension and in solution and sometimes is contaminated by specific germs of disease. The amount of suspended matter in surface water varies considerably, being greatest after heavy rains which wash the finely divided soil and earth down into streams, lakes and reservoirs. Water that contains large quantities of matter in suspension is unsuit- able for domestic and for most industrial purposes and should be filtered before using. Filtration. — Filtration is both a straining and a biological process in which most of the suspended matter and part of the hardness, color, and organic matter in raw water are removed. This is effected by passing the raw water through a thick bed of fine sand that is covered by a still finer jelly-like layer which entangles and holds any suspended matter brought in contact with it. The efficiency of a filter depends largely on this jelly-like layer, and a filter is not at its best until a suitable layer has formed. Under ordinary conditions to naturally form such a layer would take about twenty days, and to obviate such delay and bring a filter to its full bacterial efficiency in from Digitized by Microsoft® 220 Principles and Practice of Plumbing twenty to thirty minutes, coagulants are used to artificially produce the jelly layer. The coagulants generally used are sulphate of alumina (common alum) and sulphate of iron. When sulphate of alumina is added to water it decomposes into its component parts, sulphuric acid and alumina ; the sulphuric acid com- bines with lime, magnesia, or any other base present in the water, while the alumina forms a flaky precipitate that gathers together and holds whatever suspended matter it encounters, thus forming in a few hours a layer that with- out the use of coagulant would require weeks to form. The thicker the layer of sediment, the greater the bacterial efficiency of a filter, but usually after from twelve to twenty- four hours' operation, the sediment layer becomes so thick that sufficient water cannot pass through, and the filter bed must then be cleaned. Gravity Type Filter. — A filter of the subsidence grav- ity type is shown in Fig. 108. Unfiltered water, to which coagulant has been added, enters the sub- sidence basin be- neath the filter and usually tangent to the circumference, as experiment has dem- onstrated that a ro- tary motion conduces to greater and more rapid sedimentation. From the subsidence basin water rises through the hollow vertical axis, h, and overflows to the filter bed through which it percolates to the sys- tem of under drains below. The copper float, a, in the filter tank automatically regulates the supply of water and thus maintains a uniform head, while the automatic controller, e, Fig. 108 Gravity Filter Digitized by Microsoft® Principles and Practice of Plumbing 221 on the outlet or pure water pipe regulates the rate of filtration. When the filter bed is dirty it is cleaned by reversing the flow of water through the filter bed and thoroughly loosening the sand. This is effected by pumping filtered water into the sand bed through the outlet pipe, and when the sand is thoroughly loosened revolving the iron rakes, thus breaking up the jelly layer on top of the sand and stir- ring up the entire filter bed so all the grains of sand will be exposed to the scouring action of the water. The wash water and dirt from the filter bed overflow the filter tank into the annular space between the two tanks, and are car- ried out through the valve, b, to the sewer. For a few minutes after a filter bed is washed, its eflSciency is greatly lowered, so for a short time after starting, the water is allowed to fil- ter to waste througli the valve, c. After suf- ficient water has run to waste to insure a good filtrate, valve c is clos- ed, valve d opened and filtered water discharg- ed to the clear water tank through the con- troller, e. To clean the filter bed, valves c and d are closed, valve / opened and air and water alternately forced through the system of collect- ors, g, to the filter bed. Coagulant Pump. — To secure the best results the amount of coagulant used must be proportioned to the con- dition of the water; the amount varies from one-quarter grain to two grains per gallon, the exact amount for any water being determined by experiment. If sufficient coagu- lant is not fed to the raw water, it will result in an inferior filtrate, and if too much coagulant is used, it will not only increase the cost of operation, but coagulant will pass through the filter bed to the delivery mains. Some waters Fig. 300 Coiife'iilanl Pump Digitized by Microsoft® 222 Principles and Practice of Plumbing are so soft that insufficient base is present for coagulant to react upon. When such is the case, a base, usually of lime, is also added to the raw water. To feed coagulant to the raw water, some form of pump or apparatus is required that will be automatic in operation and feed a measured quantity of coagulant pro- portional to the quantity of water. A meter pump for this purpose is shown in Fig. 109. A coagulant solution of the required strength is mixed in wooden coagulant tank, a, which is connected by feed pipes to a meter-actuated duplex pump, b. The meter measures the quantity of raw water passing through; the raw water operates the pumps which dis- charge a proportional quantity of solu- tion into the raw water. All working parts of a pump or other coagulant ap- paratus should be made of bronze to r \ withstand the corroding effects of sul- ^" ' phate of alumina or sulphate of iron, which energetically attacks and de- stroys iron. Filtration Controllers. — After filter beds have been cleaned the rate of • filtration, for a while, is much faster than at other times, and is often too great for efficient results. Under work- ing conditions an excessive rate of fil- tration might disturb the jelly layer and permit raw water to pass through with but little filtration. To regulate the rate of filtration, auto- matic controllers, Fig. 110, are now generally used. In this type of controller the outlet is fitted with removeable bush- ings that regulate the discharge to the desired velocity; if the rate of filtration then becomes greater than can be dis- charged, water will fill the controller box and raise the float, thus throttling the balance valve and reducing the flow to the required rate. Efficiency of Gravity Filters.— The bacterial efli- ciency of gravity filters depends upon the use of coagulants. Fig. 310 I'MILrjiLion ConlroUoi" Digitized by Microsoft® Principles and Practice of Plumbing 223 If clear water for industrial purposes is wanted, it may be had by filtering though sand without coagulant, but for domestic water supply, where bacterial purity is required. coagulants must be used. The tabulated report of chem- ical and bacterial tests of gravity water filters, at Lorain, Digitized by Microsoft® 224 Principles and Practice of Plumbing 3 S3 P3J35IM 3,498,600 3,447,640 3,493,700 3,451,660 3,441,800 3,312,400 3,424,300 •jEo 13a -sjo -pssn suin -snB^ JO ■^mv .,*, \0 so *0 ^ O ^ ,o lo Ov\OOvO\&tt»0*OvO\ONOvCvOvO\C\ao,0\ 0,0\0«0\»0v0>0»0»0.0,0»0,0v0'0\0,0s»0>0v0,0v jaiEAV pajaliiil QOOMOOO^OOO^OONM^O^OOMOOOO'O^M .#-H010NO>OOOOfOfOOO,WN(N'^uit^00— <(Ni-iir)i-.0,Tfiior^C\ 000 'i|D.reiM 3^v.a i^^i^i^ioDwoooO^C^Sc^SSooiiiJ'^^p^w ^* -. " t- oa . O oj o U) s^ S£»25S ■ (D-*-' O a. ■o.3~.aio'SD,« > M — flijOuH" . .0,2 cc.^ w _ a) ) obsT'm .aj; 3 V-i Q* 8j '-'-*-■ © H « J o <1> a* S <^ H+j-i,a ; 'ti ^ S> O) H CB > >s i=2 a ^-r a (R n g t* -— '■ -s^- ,_ a 1) S & '"S " S ,. aSj 'vie=5S»-'- •a.Pf-- ■^ 3 E f - aB ^v; _ 1 i§i,»a^^ls-2|^J I t;a u ssgi Digitized by Microsoft® Principles and Practice of Plumbing 225 Ohio, given in Table LVII, will serve to show the efficiency of rapid sand filters. A plan of a filter house for a small city plant, showing the layout of filters, piping and apparatus, is illustrated in Fig. 111. Pressure Filters. — Pressure filters are enclosed in water-tight chambers, so that water can be driven through the filter bed by hy- draulic pressure. A Jewell pressure filter of the settling basin type is shown in Fig. 112. This filter is constructed and operated similar to the Jewell gravity type, from which it differs only by being enclosed in a water-tight case. Pressure filters are not as efficient as gravity filters, but owing to the ease with which they can be attached to a water supply system they are extensively used for house filters. Usually pressure filters are connected to the service pipe in the cel- lar, and all water used in the building passes through them. When so installed they should be provided with a by-pass to permit unfiltered water being supplied to fixtures in the building in case the filter is cut out. The bacterial efficiency of pressure filters like that of gravity filters depends upon the use of coagulants. When water is to be used for manufacturing purposes, however, a clear filtrate can be obtained without coagulants. An automatic apparatus is used to fepd coagu- lant to pressure filters. Fis. 11:; Pressure Filters Digitized by Microsoft® 226 Principles and Practice of Plumbing CHAPTER XXIV SOFTENING OF WATER Economy of Soft Waters. — Throughout the Missis- sippi Valley and in other parts of the United States where municipal water supplies are obtained from artesian wells drilled to the underlying St. Peter or Potsdam sandstone, the water is permanently, and in some localities, both tem- porarily and permanently hard. This is due to the fact that in those regions the geological formation of the upper strata is limestone, and in percolating through the limestone, the water, which originally was soft, dissolves from rock, car- bonates or sulphates of lime or magnesia. The solvent capacity of water for carbonates and sulphates of lime is greater when the water is cold ; therefore, deep well waters in limestone regions usually are saturated with lime or magnesia, and when heated in water tanks or boilers to a temperature greater than 140 degrees Fahrenheit, the point of saturation is lowered and lime is precipitated or liber- ated and forms a hard scale or incrustation in waterbacks and boilers. The effect of boiler incrustation is to shorten the life of a boiler and decrease the efficiency of the appa- ratus while in service. It is accepted by good authority that : 1/16-inch lime scale means a loss of 13 per cent, of fuel. %-inch lime scale means a loss of 22 per cent, of fuel. M-inch lime scale means a loss of 38 per cent, of fuel. %-inch lime scale means a loss of 50 per cent, of fuel. Mi-incH lime scale means a loss of 60 per cent, of fuel, ■yi-inch lime scale means a loss of 91 per cent, of fuel. These values are probably a little high, but making due allowance for inaccuracies the table still serves to show the enormous waste of coal due to boiler incrustation. Incrustation of waterbacks and water heaters not only decreases their efficiency while in service, but is also a source of expense for repairs. In limestone regions water- backs and heaters become choked with lime and require Digitized by Microsoft® Principles and Practice of Plumbing 227 cleaning at certain intervals of time ranging from one to six months. In the household, the increased consumption of soap to soften hard water is a further item of expense. The amount of commercial soap required for this purpose, with waters of different degrees of hardness, can be seen in Table LVIII. TABLE LVIII. Soap Required to Soften Water 1° 3° 4° 8» 12° 16° Gallons of Hardness Hardness Hardness Hardness Hardness Hardness Water Soap Soap Soap Soap Soap Soap Pounds Pounds Pounds Pounds Pounds Pounds 100 0.119 0.357 .476 .952 1.428 1.904 1,000 1.19 3.57 4.76 9.52 14.28 19.04 10,000 11.90 35.7 47.6 95.2 142.8 190.4 100,000 119.00 357. 476. 952. 1428. 1904. 1,000,000 1190.00 3570. 4760. 9520. 14280. 19040. Many industrial concerns, like breweries, paper mills, distilleries, refineries, ice factories and laundries, require soft water, not only for boiler feed, but also for industrial purposes, and use some modification of the Clark-Porter water softening process. The Clark process consists of adding lime water to temporarily hard water to remove the carbonates of lime ci' magnesia. The lime acts upon the bicarbonates in the hard water, releasing the extra carbonic acid gas required to form the bicarbonates, and precipitates the carbonates of lime which are insoluble. The Porter process consists of adding soda ash to permanently hard water to remove the sulphates of lime and magnesia, and stirring up the treated water with pad- dles to mix it. When soda ash is added to permanently hard water, it reacts upon the sulphates of lime and mag- nesia, decomposes them and forms insoluble carbonates which are precipitated. The reagents generally used in w.ater softening are caustic lime (common quick lime) and soda ash, Other reagents can be used, but the above are generally selected Digitized by Microsoft® 228 Principles and Practice of Plumbing on account of their cheapness and because they are readily obtainable in any market. Water Softening Apparatus. — An apparatus for softening water consists of a mixing chamber for the chem- ical reagents, a settling basin for the treated water after the reagent is added and a filter to remove from the soft- ened water the base acted upon by the chemical. There are two general arrangements of apparatus for softening water. One arrangement is known as the closed or pressure system, and the other arrangement, as the gravity system. The general arrangement of the Scaife pressure system as used for softening feed water for boilers is shown in Fig. 113. Fig. 113 I'l'cssiire Wali'i- Softeniufc' Systi'in Feed water enters the open heater, a, where some of the temporary hardness is removed by raising the temper- ature to 200 or 210 degrees Fahrenheit, thus driving off some of the free carbonic acid gas and precipitating car- bonates of lime and magnesia on removable pans inside of the heater. From the heater the water is forced by the boiler feed pump, b, into a large precipitating tank, c, where the chemical reagents are introduced by means of two small pumps, d, d. In the precipitating tank most of the remain- ing carbonates and sulphates of lime and magnesia are pre- cipitated; some of the lighter particles, however, are carried Digitized by Microsoft® Principles and Practice of Plumbing 229 in suspension to the filters, e, e, where along with other im- purities they are removed. When this system is used for industrial or for domestic purposes, the heater and feed water pumps may be omitted and the hard water discharged directly into the precipitat- Fig. 114 Gravity Water Softening Apparatus ing tank. When the heater is omitted, however, a larger quantity of reagent is required. A gravity apparatus for water softening is shown in Fig. 114. In this system of treatment, lime is slacked in the trough, a, after which it is emptied into the saturator, b, Digitized by Microsoft® 2S0 Principles and Practice of Plumbing w. -4.- - where it can be diluted to the required consistency and be kept agitated by revolving paddles. In a tank, c, a solution of soda ash is prepared, which, like the lime solution, is agitated by revolving paddles operated by the water motor, d. Lime solution is fed to the raw water through pipe e. and soda solution is fed to the raw water through pipe /. Ey means of an automatic proportional water motor, a measured quantity of water and proportional amounts of either lime, soda, or both lime and soda, are introduced into the standpipe, g, the water flowing in through pipe, h. Baffle plates in the standpipe thoroughly mix and agitate the treated water, thus aiding precipitation. The lime deposited in standpipe, g, is washed out through the valved pipe, i. The treated water overflows the top of the stand- pipe, passes under the baffle plate, j, up through the filters and overflows through trough, k, and pipe, I, to a collecting or storage reservoir. Sludge from precipitation in the tank settles to the cone-shaped bottom and is washed out through pipe, m. A float, n, controls the supply valve, o, thus mak- ing the apparatus automatic in operation. When the water to be treated is obtained from a stream or other surface source where the conditions of the water are not uniform, it is better to use an intermittent type of apparatus. By this system a large quantity of water is put in a tank and treated ; while that tank is being emptied, a second tank is filled, the water tested and the right proportion of reagent mixed to treat it. In this man- ner each tank of water is separately tested and the correct proportion of chemicals added. The Permutit Process of Softening Water. — The Permutit process for softening water is simple of operation and applicable for both domestic and industrial uses. The softening is accomplished automatically by passing the hard water through a tank, as shown in Fig. 115, containing porous but insoluble crystals of aluminum-sodium silicate, where an exchange takes place between the lime and mag- nesia in the water, and the sodium forming the base of the crystals. When the sodium base of the Permutit becomes ex- Digitized by Microsoft® Principles and Practice of Plumbing 231 hausted, as it does after a given quantity of water has been softened by it, it is necessary to renew the sodium. This is done by adding a solution of common salt to the Permutit, which by mass action drives out the calcium and magnesium, leaving sodium in their place. The calcium and mag- nesium salts are run off through the drain pipes. This process can be carried on indefinitely, as the life of the Permutit is unlimited. The only cost of operation is the cost of common salt. Usually the regenerating process, as it is called, is carried on at night. rtiHTseo • cnt/fse I > /Miy tV/^TC/r ML^T ■^MS/A/s ff/trf/f/f/ce-r \fi£eefJc/>^TMs MLi/e ''oi/n.errav Lrsoci/r/ou /fflNSINS IV^TCff .OUTL£T Fig. 1].-, Permutit Apparatus for Softening Water The regenerating solution generally used contains about 10 per cent, of sodium chloride (common salt). This reaction also obeys the law of mass action, and since the Permutit has a greater affinity for calcium than for sodium, three to four times as much salt as is theoretically required is provided, and further to facilitate the action the solution is usually heated to 100 to 120 degrees Fahrenheit. Admission of the solution to the filter is regulated auto- matically at a very slow rate to permit the solution thor- Digitized by Microsoft® 232 Principles and Practice of Plumbing oughly to penetrate the grains or zeolites. Admission occupies 4 to 5 hours and, when the charge is completely impregnated the solution is left in the filter for about the same period. The charge is then drained and washed thoroughly to remove all traces of salt. Since the regener- ative process is completed in about 8 hours, the installation of one filter will satisfy the demands of the ordinary plant, but where continuous service is required two filters will be necessary for alternate softening and regeneration. Data of Operation. — Water of any degree of hard- ness may be softened by passing it through a layer of Permutit 24 to 40 inches in depth at a rate of 10 to 16 feet an hour; and the speed of filtration usually adopted lies between these limits. The permissible speed of filtration can be raised by increasing the depth of Permutit charge, but it is limited by the fact that for efficient action the water must have time to penetrate the interior of the grains. The extreme limits of speed are : for water containing 0.01 per cent, lime, approximately 27 feet; 0.02 per cent., 16 feet; and 0.03 per cent., 10 feet an hour. The volume of water treated depends, of course, on the area of the charge. The filtering apparatus shown in the illustration is of the gravity type, but a closed type for pressure working is employed in some cases. In either type, the charge of Permutit rests on a bed of crushed flint and a similar bed of flint, carried on a perforated plate, is placed in the upper part of the filter to prevent the escape of Permutit during the regenerative process. The principle of operation of the Permutit process is based on the peculiar properties of zeolites. Natural zeolites are combinations of aluminum and other bases with silicic acid. The peculiarity of zeolites is the property of changing their bases for others. That is, a zeolite formed of silica, aluminum and sodium or salt can exchange its base of salt for a base of lime or magnesia ; and this prop- erty is made use of in the softening of water by the Permutit process. The zeolites used are artificial, and in the moist condi- tion are of a granular or flaky form with a lustre like that Digitized by Microsoft® Principles and Practice of Plumbing 233 of mother-of-pearl. Owing to its porosity, in the dry state the material readily absorbs about 50 per cent, of water, and must therefore be stored in a dry place safe from frost. The water flowing to Permutit water softener must be clear, free from iron and mechanical impurities, and the temperature should not be more than 100 degrees Fahren- heit. The artificial zeolites used in this process are obtained by fusing together feldspar, kaolin, clay and soda in definite proportions. It will be seen, therefore, that they partake of the nature of a very porous earthenware or porcelain. Digitized by Microsoft® 234 Principles and Practice of Plumbing CHAPTER XXV STERILIZING WATER WITH ULTRA VIOLET RAYS The sterilization of water by means of the ultra violet rays is based on the well-known germicidal action of sun- light. What is known as the white light of the sun is really the result of a blend of all colors of the rainbow. This white light can be broken up into its component parts by passing a beam of the light through a triangular glass prism which gives the solar spectrum. Of the visible colors, the blue or violet is at one end of the spectrum, and the red at the other extreme. Beyond the visible spectrum are invisible light waves known as the ultra rays. Beyond the violet rays are the ultra violet rays, which of course are invisible. All light is due to wave vibrations. The difference in color is due to a difference in wave length. Of the visible colors the shortest are those of the violet. Just beyond the violet the ultra violet waves are even shorter and more intense in their vibrations. The ultra violet rays are the most destructive to bac- terial life. The well-known sterilizing action of sunlight is due to the short wave vibrations of the violet, ultra violet and other rays it contains. The exact action or reaction which proves so destruc- tive to bacterial life is not known. It is believed, however, that the ultra violet rays first produce a coagulation of the protoplasm, which results finally in an entire disappearance of the body of the germ. E^ihaustive tests show that the bacteria are killed, not merely shocked into a dormant state with the possibility of future recovery. They also show that the bacterial destruction is due directly to the ultra violet rays, not through the medium of oxidation by chemi- cals formed by the contact of the rays with the water, nor by any other indirect means. The temperature of the water has no effect on this bacterial action. The same germicidal Digitized by Microsoft® Principles and Practice of Plumbing 235 action is found when clear ice is subjected to ultra violet rays as when water of any temperature is exposed. It requires only a comparatively short time for ultra violet rays to exercise their germicidal action on water- borne bacteria. The approximate length of exposure to the ultra violet rays required for complete destruction can be found in Table LIX. TABLE LIX. Time Required for Ultra Violet Ray Steril- ization Kind of Bacteria Staphylococcus Aureus. B. Cholera B. T>-phoid B. Dj'sentery (Shigo) . . . B- Dysentery (Dopter) . B. Coli Aerogenes Capsulatus . . B. Tetanus. , Exposure Required for Complete Sterilization 12 Seconds 17 Seconds 18 Seconds 17 Seconds 16 Seconds 18 Seconds 21 Seconds 40 Seconds The depth of water that ultra violet rays will sterilize depends upon the strength of the light and length of expos- ure. In practice, as the exposure must be comparatively short, the film of water must be correspondingly thin. In ultra violet ray sterilizing apparatus the film of water flow- ing past the light varies with the type and size of the appa- ratus, from one-half inch to eight inches in depth. Ultra Violet Ray Apparatus. — An ultra violet ray apparatus is simply a housing or casing with a transparent cylinder or tube inside which separates the light from the water. The water flows over and is in contact with this tube, while the light is inside of it safe from contact with the water. This transparent cylinder is made of quartz, ice and quartz being the only known solid substances which will permit the ultra violet rays to pass through them. A glass cylinder in this place would prevent sterilization, for the ultra violet r^ys would not pass through the glass. The quartz tube is made water tight by stuffing boxes packed with rubber and protected by aluminum heat rings. Digitized by Microsoft® 236 Principles and Practice of Plumbing The water flows over this quartz cylinder and is thus exposed to the light from the lamp within the cylinder. The space between the apparatus housing and the outside of the quartz cylinder varies from one-half inch to eight inches, or if deeper, baffle plates are provided to stir the water and turn it over during its passage, and narrow the passage so water cannot flow through without having been exposed to the light in a comparatively thin stream. The rays are produced in an ultra violet ray apparatus by a mercury vapor lamp — a mercury vapor arc in a vacuum. The lamp consists of a straight quartz tube with a bowl at one end, like a clay pipe. This tube is partially filled with mercury. Mercury is an electric conductor. When, therefore, two ends of the lamp are connected in an electric circuit, electricity flows through the mercury, but without producing any ultra violet rays. To form the mer- cury vapor arc the mercury bridge must be broken. This is done by raising the stem of the lamp slightly, either auto- matically or by hand. A short mercury vapor arc is then produced, just as the electric spark spans the distance be- tween the carbon in an arc light. The pressure of the mercury vapor gradually forces the mercury up in the bowl, until in a few minutes no mercury is left in the stem. The mercury vapor arc then extends the full length of the tube, and ultra violet rays of great intensity are produced. The mercury lamp is placed inside of the quartz cylin- der in the ultra violet ray apparatus, and is fitted up to tip automatically once the current is turned on. The ultra violet rays have no perceptible effect on the water treated, other than their germicidal action. The treatment does not change the temperature, taste, appear- ance, chemical or mineral properties. It does not charge with carbon dioxide, nor does it make the water "flat." For sterilization by means of ultra violet rays the water must be clear and free from suspended matter. If it is not, a bacterium might get behind or inside a suspended particle and escape exposure to the rays. If, therefore, the water is not clear, it must be filtered before sterilization. Simple filtration without coaigulation may then be resorted Digitized by Microsoft® Principles and Practice of Plumbing 237 to, the ultra violet rays affecting sterilization without add- ing an objectionable sulphate of iron or sulphate of alumina to the water. While water must be free from suspended matter and turbidity for successful treatment with ultra violet rays, a certain amount of color and turbidity are permissible, so long as the color is not a deep one, or the turbidity over fifteen parts per million. The "dosage" of application of the ultra violet rays is independent of the mineral or organic content of the water, and since no physical or chemical change is produced in the water by the ultra violet rays, a very heavy over-dosage beyond that theoretically required can be used, thereby giv- ing full protection against unusual conditions which arise in most public water supplies. Ultra violet ray apparatus are made in three types — portable, gravity and pressure. The pressure type is con- nected to the water supply system and the water flows through the apparatus under pressure. The gravity is an open type sterilizer through which the water flows by grav- ity under a very slight head. Digitized by Microsoft® 238 Principles and Practice of Plumbing CHAPTER XXVI PREVENTION OF RUSTING IN WATER PIPES AND TANKS The treatment of water to prevent it rusting pipes is not, strictly speaking, a purification process, nor is it, like filtration and ultra violet ray sterilization, a sanitary pre- caution. It is purely an economic measure, like water softening, intended to prevent pecuniary loss. There are two methods of rust prevention, known re- spectively as De-Aerating and as Deoxidizing or Deactivat- ing. The two methods are wholly unlike each other, al- though they achieve the same result, the prevention of rust- ing or pitting of iron or steel water pipes and tanks. Neither system is applicable to steam or other piping sys- tems. They are used exclusively for water supply systems in buildings. Rust prevention is affected by removing the air or oxygen from the water before it reaches the distributing system. Air, while not an element of water, is a natural constituent of it. At atmospheric pressure and ordinary temperature, water will absorb four per cent, of its own volume of air. By increasing the pressure of water, its capacity for absorption is increased in direct proportion. That is, if the pressure be increased to two atmospheres, the temperature remaining unchanged, pure water will absorb eight per cent, of its volume of air. Under a head of 100 feet, a moderate pressure in water supplies, water will absorb twelve per cent, of its volume of air. Without the air that is dissolved in all natural waters, fish and other aquatic animals could not live, and all water vegetation would die. Without wind to create waves and ripples, the air would soon become exhausted from ponds and lakes. In like manner, without air in the water supplied to build.- ings, the pipes would not rust, nor would iron of any kind rust in water from which all air was expelled. It is well Digitized by Microsoft® Principles and Practice of Plumbing 239 known to chemists that corrosion is directly proportional to the amount of free oxygen dissolved in water. While waiter under compression can absorb four per cent, of air for each atmosphere of pressure, it seldom con- tains more than four per cent., as that is the point of satura- tion at atmospheric pressure, which is the pressure at which it is taken into the system. The air is made up of .21 per cent, by volume of oxygen; .78 per cent, nitrogen, and .01 per cent, argon. It is the oxygen in the air that causes the corrosion, and with four per cent, of air in water the oxygen content would be .84 per cent., or almost one per cent. Water and iron alone do not produce rust. Iron and air alone cannot produce rust. What is needed is iron, air and water. Take away any one of these three essentials, and rust will be prevented. The iron or the water cannot be taken away in a water supply system, so in both deacti- vating and de-aerating the air — or dissolved oxygen — is re- moved. Rust occupies about ten times the volume of the iron which produced it. This accounts for small pipes being so badly choked they materially reduce the supply of water, particularly in the upper stories of buildings. The formation of rust is greater in the hot water sys- tem than in the cold water pipes. This is probably due to the fact that heating water lessens its absorption in direct proportion to the amount of heat applied. The relative volume of air absorbed is in all cases directly as the press- ure, and inversely as the temperature. Thus, as has already been stated, if the pressure be increased it will absorb more air, and if it be heated it will absorb cor- respondingly less air. The air or oxygen liberated by heat in the hot water system is free to attack the pipes. That is why there is so much more trouble from hot water pipes pitting than from cold water pipes, and that is why rust prevention is applied generally to the hot water system and seldom to the cold, although the treatment is equally applicable to any water, hot, cold, fresh or salt. Digitized by Microsoft® 240 Principles and Practice of Plumbing Deactivating or Deoxidizing Apparatus. — In the de- activating method of rust prevention, the apparatus is located in the basement or cellar near the heater, and water flows from the heater to the deactivating tank, while all its dissolved oxygen is liberated from the water and is ready to unite with anything suitable for which it has an affinity. The deactivating tank is partially filled with iron strips which the water attacks, producing all the rust of which it is capable under the circumstances. If it did not expend its energy there, it would attack and pit the pipes. The tank is easily cleaned and charged with deactivating material whenever necessary. ^ft=v^=^^r;.4> Fig. 116 Upactivating ApparntMs A deactivating system in which coal is used for fuel is shown in Fig. 116. From the coal heater, c, the heated water flows in the direction of the arrows to the deactivator, d, then to the filter, /, with a by-pass direct to the building. When the hot water leaves the deactivating tank it contains rust. This rust is removed by the filter so that when the water enters the distributing system it is clean and prac- tically freed from oxygen. Water enters the system through the pipe a, passes through or by-passes around the coagulate tank, e, as the Digitized by Microsoft® Principles and Practice of Plumbing 241 case may be, into the heater. The circulation pipe returns, as shown by the arrows, over the recording thermometer, g, and flows through the re-heater, h, then back to the house supply, b, again. Fig. 117 Deactivating Apparatus In Fig. 117 is shown the same system in which steam coils take the place of the coal heater. Cold water enters through pipe, a, passing through or by-passing the coagulate tank, e, to the heater, c, which is provided with a steam coil. From the steam coil it passes to the deactivator, d, which is by-passed as in the preceding illustration. From the deactivator it flows to the filter to remove the rust, then out through b to the hot water distributing system. The tank, h, is a steam heated re-circulation heater to boost the tem- perature of the water in the circulation pipe from the build- ing, so it can again mingle with the house supply without passing through the deactivator again. De-Aerating Apparatus. — The de-aerating process of rust prevention is based on the fact that very hot water cannot hold air in solution. It is assisted by the further fact that reducing the pressure, even of cold water, reduces the amount of air it can hold in solution. In de-activation the water is almost boiled in an open type of apparatus on the roof of a building, or above the highest outlet in the Digitized by Microsoft® 242 Principles and Practice of Plumbing system. The treated water then flows direct to the hot water heater in the basement, thence to the hot water dis- tributing system. The deactivating apparatus can be located in the basement or sub^basement of a tall building, but its operation is not so satisfactory as when at the top of the building. Heating the water in open tanks at the top of the building removes about ninety per cent, of the dissolved 1''?VENT TO V ATMOSPHEFE kJO HOUSE HEATERS I'-lg. 118 Df aeiiiling Ai)i).natus Digitized by Microsoft® Principles and Practice of Ptumbing 243 Oeactivator- •SrwiOft^t JreAnFtruvm\ r^oi'/^vre U. ^fr*V/W '""'TT^aTV^ ^ tera.'y '•• • " ' "'', nszxzzxTxirzzzr CiircutATn v Jferu^9te-J^ t j » oxygen. This reduces the corrosion to about one-tenth of the rate that would obtain with raw untreated water, giving to hot-water pipes a prolonged life with a ratio of about one to ten. A deaerat- ing apparatus is shoWn diagram- atically in Fig. 118. Cold water enters the in- take chamber, /, flows up through the spiral coils, g, through the lower part of the tank, where the treated wa- ter is stored ready to be drawn. In the storage com- partment the in- coming water absorbs some of the heat from the treated wa- ter, thereby pre- paring it for the next stage in the coils, h. These coils are sur- rounded by steam, and the water is raised to a temperature of 207 degrees Fahrenheit, at which temperature it readily parts with the dissolved oxygen, which is liberated as the water falls over the baffle plates, k, into the funnel, I, and through the duct, m, to the storage or exchange chamber. Fig. 119 Method of Installing De-aerator Digitized by Microsoft® 244 Principles and Practice of Plumbing The temperature of the water in the coils, h, is regulated by the automatic temperature control, s. It parts with some of its heat, as before explained, to the water in the coils, g, and reaches the water heater in the cellar at a tem- perature of about 120 degrees Fahrenheit. The diagram. Fig. 119, shows the way a de-aerating apparatus is installed in a building with relation to the other parts of the water supply system. Digitized by Microsoft® Principles and Practice ■ of Plumbing 245 PART IV HOT WATER SUPPLY CHAPTER XXVII WATER HEATING APPARATUS Properties of Heat Transfer of Heat. — When two bodies of different tem- peratures are near each other a transfer of heat takes place from the hotter to the colder body. This tendency towards maintaining an equilibrium of temperature is universal and the transfer of heat may take place in any of three ways; by conduction by convection or by radiation. Conduction is the progressive movement of heat through a substance without perceptible movement of the molecules ; if one end of a poker be held in a fire; the other TABLE LX. Absorption and Radiation of Heat Substance Lampblack Water Carbonate of lead Writing paper Marble Isinglass Ordinary glass Ice Cast iron Wrought iron, polished Steel, polished Tin Brass, cast, dead polished Brass, hammered, dead polished. . Brass, cast, bright polished Brass, hammered, bright polished Copper, varnished Copper deposited on iron. ....... Copper, hammered or cast Powers Radiating or Absorbing 100 100 100 98 93 to 9 91 90 85 25 23 17 15 11 9 7 7 14 7 7 Reflecting 2 7to"'2 9 10 15 75 77 83 85 89 91 93 93 86 93 93 Digitized by Microsoft® 246 Principles and Practice of Plumbing end will become heated by conduction. Water in a water- back or vessel becomes heated from the flames and hot gases of a fire by conduction of heat through the metal walls of the waterback or vessel. Convection is the transfer of heat by movement or cir- culation of the molecules of the substance to be heated. Water in a vessel placed on a stove is heated by local circula- tion of the water. Fluids and gases, such as water or air, can be heated only by convection. This is due to the fact that when heat is applied to a fluid, the parti- cles in contact with the heat expand in bulk, consequently become lighter in weight and are replaced by colder and denser particles. Radiation is the transmission of heat through space from a warm body to one of lower temperature. For example, the Earth is warmed by radiation from the Sun. Radiant heat does not heat the air through which it passes; it travels direct and in straight lines until intercepted, when it is reflected or ab- sorbed by this interceptive body. The cooler body will reflect or absorb or partly reflect and partly absorb all the heat rays it inter- cepts and the sum of the absorption and re- flection equals the total of the intercepted rays. Absorption and radiation are equal and opposite. The better the absorptive power of a substance the better radiating material it would make. Lampblack, which has absorbing and radiating powers rated at 100, is taken as the standard of comparison. In proportion as the reflecting power of a substance diminishes, its power to absorb or radiate heat increases. The absorbing, radiating and reflecting capacity of various substances are given in Table LX. Measurement of Heat.— The amount of heat trans- mitted to water is measured by the British Thermal Unit usually abbreviated B. T. U. A B. T. U. is the quantity of heat required to raise the tempeiratur^ of Qne pound of water Fig. 120 Thermometer for Indicating Water Temperatures Digitized by Microsoft® Principles and Practice of Plumbing 2Al from 62 to 63 degrees Fahrenheit. In practice it is taken as the quantity of heat required to raise one pound of water 1 degree Fahrenheit. Measurement of Temperature. — The temperature of water is measured by a mercury thermometer. For meas- uring water temperatures, thermometers, Fig. 120, should have a scale ranging from 60 degrees Fahrenheit to 270 degrees Fahrenheit, and should be so constructed that when screwed into a fitting the mercury bulb, a, will project into the pipe and thus be in contact with the hot water. Transmission of Heat.— The quantity of heat trans- mitted to water through a vessel or tube depends on the difference in temperature between the heating medium and the absorbing water, the thickness of the walls of the vessel or tube, and the material of which it is made. All other conditions being equal, copper pipes will transmit 50 per cent, more heat than iron pipes, and cast iron surfaces will transmit about 60 per cent, less than an equal area of iron TABLE LXI. Transmission of Heat Steam con- Heat trans- densed per mitted per square foot per square foot per degree differ- degree differ- ence of tem- ence of tem- Experi- menters Character of Surface perature per Iiour perature per hour Remarks Heat- Evapo- Heat- Evapo- ing rating ing rating Pounds Pounds B.TU. B.T.U. Copper coils .292 .981 315 974 Laurens i 2 Copper coils . . • ■ 1.20 1120 Copper coil .268 1.26 280 1200 Perkins Iron coil .24 215 r 100 lbs. \ Pressiu-e Perl; ins Iron coil .22 208.2 / 10 lbs. \ Pressure Box Iron tube .235 230 Box Iron tube .196 230 Box Iron tube .206 207 Havrez Cast iron boiler .077 .10.5 S2 100 Kent's Pocketbook. Digitized by Microsoft® 248 Principles and Practice of Plumbing pipe surface. The relative transmission of heat for dif- ferent metals is shown in Table LXI. From the above table of experiments, Table LXII of average heat units transmitted through various sub- stances is adduced. The table is based on the assumption that the outer surface is clean and free from soot or ashes, and that the inner surface is free from incrustations of lime or other substances. TABLE LXII. Comparison of Different Heat Transmitting Surfaces Materials Heat transmitted per square foot of heating surface each hour for each degree Fahr. difference between the heating medium and the water Copper plate Copper pipe Wrought iron or steel pipe or surface Cast iron surface 275 B. T. U. 300 B. T. IT. 200 B. T. U. SOB. T.U. Temperature of Fires. — Temperature tests of a fire by observation can be told in a fairly exact manner by Table LXIII. TABLE LXIIL Temperature of Fires Appearance of Fire Approximate Temperature, Fahr. Red, just visible Red, dull Dull red, cherry About 977 degrees About 1290 degrees About 1470 degrees About 1650 degrees About 1830 degrees About 2010 degrees About 2190 degrees About 2370 degrees About 2550 degrees About 2730 degrees Red, bright Orange, dull Orange, bright White heat. . Wliite, welding White, dazzling. Properties of Hot Water Expansion of Water. — When water at or above the temperature of 39.1 degrees Fahrenheit is heated it expands in volume. The temperature 39.1 degrees Fahrenheit is known as the point of maximum density. When the water Digitized by Microsoft® Principles and Practice of Plumbing 249 is at a lower temperature the application of heat causes it to contract in bulk and the application of cold causes it to expand. The expansion, weight, density and comparative vol- ume of pure water at different temperatures can be found in Table LXIV. The increase in bulk of a given quantity of water can be found by the formula : v= , in which v. = final volume of water, o = original volume of water, q c = comparative volume of water at final temperature, q = comparative volume of water at original temperature. Example — What will be the final volume in a vessel containing 40 gallons of water at 62 degrees Fahr. when raised to a temperature of 200 degrees Fahr.? Solution — In Table LXIV it will be seen that the comparative volume of water at 62 degrees Fahr. is 1.00101 and at 200 degrees Fahr. 1.03889. Sub- stituting those values in the formula, y _ 40 X 1.03889 _ ^^^^ gallons final volume.— Answer. 1.00101 The contraction in bulk of a given quantity of water oc can be found by the formula, V = — as in the former case, q with this difference, however, that the original temperature and volume in this case is the higher one, while the final temperature and volume is the smaller one. Example — What will be the final volume of 41.514 gallons of water that is cooled from 200 degrees Fahr. to 62 degrees Fahr.? Solution- M:^*- X ^'^^-^ = 40 gallons.-Answer. 1.03889 Boiling Point of Water. — The temperature at which water boils varies with the pressure. In a vacuum of 13.69 pounds below atmospheric pressure water boils at a tem- perature of 102.018 degrees Fahrenheit. At atmospheric pressure, which is generally taken as 14.7 pounds per square inch, water boils at 212 degrees Fahrenheit. At 15.31 pounds pressure above atmospheric pressure water boils at a temperature of 250.293 degrees Fahrenheit. The Digitized by Microsoft® 250 Principles and Practice of Plumbing 09 ti ft -, 1^ Pi e g « £ ""^ IB (13 t! 5 "< © w J s 5 Q a> o c Q ^ "S < g s is 5 a XI s hj hj i g fe g 1 S .^ S £ ^S -Sfi ■sI'Sfe^E Jig «2 ^ (0 p_ m 0, to s? ^^ ^s; .^gj-s K'ss: 1' a ftg JS^£2 ft £2 B. £3 ft«ftoi°-m=: ram H H H H oi T3 O CS Oi '^ 00 to ■<:tH CO i-H Oi GO CO iM =0 "* CD lO CO O t^ '* 55 "^ "H S s WOOS^t-COiO^CCrHOOsOOt-O C^I>^iO(N ^ (N lO 'Sii£ r-H 1-1 o o o o o o o o ooioi oici oiooodt^i^ "^ "? "^ ^-o £ CO^DCOcDCDCDcDcDCDCDCOiOlCiC'O iOiO»0>OiC ^O »0 >0 O IM '* l:^ O CO (D 00 (M O to "5 Oli-^tNtMl^ Oi ^O CO 0,.>-S m ^0 Ol Ci Oi C5 C; C; O G5 C5 C: Ol Cl O OS C5 CSOiOiOC; CO GO GO 1^ OO O O C; O O O OO OO O O C: O C O O C: O O C -u O-^OOiOcCOOOOC: oj ^ C0C0-*0COOCOOO00^-<**'*O OiOOl-^GOCi 00 i-i -:t^ OOWcOiOCDGi'-HCOiOOOO'-'CO-^cD (M!i^ lOCOt'-OOOO ^ CO -^ So OOOOOOOOOOOOOOO OOOOO ^ ,-) ^ «!►? c« (M o > i^« , i t; 0»00»00>COtOOiOO"50(N(N OOOOOO 00 cD O ^ ^ ^ ^ ^ ^ ^ ^ Wt-i(M (M CS ^S "S -^ ^ V a ' •5 - oj" -S-S e •" .-2 S aJ= GOC-liOiOC^CO OlO ^C^lu^'> lo" §••5 " (5 (S- ^ ^ ^ ^ ^ ^ 00" 0" c> d d d d d d c i:^ ocooicncoo ICO XTtH.-Ha5Q030i050irj*a>oiOigsqio;ooj02 OOOOXOso ^M COt^O^COCOOlt^iCiOCOCOoOOOCOCOgMg^ 00i050:i0i0 00 00 00 00 Ic" o «1 O 03 IM O > e:- WOOOOrH — 1 ^ ^ rH rH WrH r-l — . ^ r^ ^ r-.T-H ^ -t T-H ^^ ^ ^ ^ bj; p ^1 C» t'T C: 'C cr (M 1": "M 'O C: 'O C: 'T »0 r"- vq >0 O '"^ CO CO CO r^* -^ rt^ lO 10 «-0 25 CD -^ l^ w OC 00 C-. wJ C ^ '-« C^ CM CO CO ^ ;2; Digitized by Microsoft® Principles and Practice of Plumbing 25l i"elation between the boiling temperature of water and the pressure is absolute; pressure cannot be increased without also increasing the temperature of the boiling point of the water, nor can the temperature of the boiling point of the water be increased without increasing the pressure. The temperature and pressure of boiling water and the tempera- TABLE LXV. Boiling Point of Water d « <*. 1 tM«H 1 1 1 C V Ul 1 i*-t« 1 1 ( o- ." V 3 i" ^t. iMi 1" a iMi bo C 5} 1 s-S "II "II 1 2 3 1 2 3 1 102.018 20623 46 -275.704 563.0 2 126.302 10730 48 278.348 540.9 a 141.654 7325 50 280.904 520.5 4 153.122 5588 52 283.381 501.7 .') 162.370 4530 54 285.781 484.2 6 170. 173 3816 56 288.111 467.9 7 176.945 3302 58 290.374 452.7 8 182.952 2912 60 292.575 438.5 9 188.357 2607 62 294.717 425.2 10 193.284 2361 64 296.805 412.6 11 197.814 2159 66 298.842 400.8 12 202.012 1990 68 300.831 389.8 13 205.929 1845 70 302.774 379.3 14 205.604 1721 72 304.669 369.4 14.69 212.000 1646 74 306.526 360.0 15 213.067 1614 76 308,344 351.1 l(i 216.347 1519 78 310.123 342.6 17 219.452 1434 80 311.866 334.5 IS 222.424 1359 82 313.576 326.8 19 225.255 1292 84 315.250 319.5 20 227.964 1231 86 316.893 312.5 22 233.069 1126 88 318.510 305.8 24 237.803 1038 90 320.094 299.4 26 242.225 962.3 92 321.653 293.2 28 246.376 897.6 94 323. 183 287.3 30 250.293 841.3 96 324.688 281.7 32 254.002 791.8 98 326.169 276.3 34 257.523 748.0 100 327. C25 271.1 36 260.833 708.8 105 331.169 258.9 38 264.093 673.7 110 334.682 247.8 40 267.168 642.0 115 337.874 237.6 •12 270. 122 613.3 120 341,058 228.3 44 272.965 587.0 Digitized by Microsoft® 252 Principles and Practice of Plumbing ture and pressure of the steam in contact with it are always equal. The relative pressure and temperature of boiling water and steam, also the volume of steam at that pressure com- pared to the volume of water of which it is composed can be found in Table LXV. Circulation op Water. — Water is a poor conductor of heat. It cannot be heated by conduction or by radiation. If heat is applied to the top of a vessel of water, but slight rise of temperature will result. Water must be heated by circulation or convection, and to cause the water to circulate the heat must be applied at the lowest part of the containing vessel. If heat is applied to the bottom of a vessel of water, the water immediately begins to circulate. The water directly above where the heat is applied is heated by conduction, expands in bulk, consequently becomes lighter. It is then displaced by the cooler and denser water surrounding it, which in turn becomes heated and is displaced by the surrounding water ; thus establishing local circulation of the water inside of the vessel. If in place of a vessel of water a U-shaped tube, Fig. 121, be used and the ends of the loop connected at the top, as shown in the illustration, the water will rise in the leg of the tube to which the heat is applied, and will descend in the other leg to replace the ascending column of water. This establishes a continuous movement of the entire volume of water in the tubes in the direction of the arrows. This movement is known as circulation in a circuit. That is what occurs when water in a storage tank or range boiler is heated from a waterback or water heater. The velocity of circulation in a circuit depends upon the temperature to which the water is heated and the height 0- »i»i/ Fig. 121 Circulation of Watei' Digitized by Microsoft® Principles and Practice of Plumbing 253 of the circuit. Thus with a hot fire and a high loop the velocity of flow would be much greater than with the same loop and a slow fire or with a hot fire and a low loop. The chief cause retarding circulation is friction, therefore short radius bends, contracted waterways, small pipes and un- reamed pipe ends should be avoided when installing hot water supply systems. Mixing Waters of Different Temperatures. — The resulting temperature when two or more quantities of water of different temperatures are mixed, can be found by divid- ing the total number of heat units by the weight of water. Instead of reducing the water to pounds weight, however, the method can be shortened as shown by the following example and solution. Example — What will be the temperature resulting from mixing 30 gallons of water at 50 degrees Fahrenheit, with 15 gallons of water at 180 degrees temperature? Solution — 30 gals, of water at 50° equals 30 X 50 or 1500 15 gals, of water at 180° equals 15 X 180 or 2700 45 4200 4200 divided by 45 gives 93 plus, which would be the temperature of the water after mixture. Three, five, ten or any number of quantities may be mixed the same way, and the resulting temperatures deter- mined by dividing the total quantity of heat found by add- ing the products of the several volumes times their tem- peratures, by the total number of gallons in the mixture. RULE II — To find the amount and temperature of water required, to result in a mixture of given volume and temperature, the cold or hot water volume and temperature being known: Multiply the total gallons of the required mixture by the required resultant temperature to find the total degree-gallon requirement; subtract from that product the product of the known number of gallons and the known temperature, which product is the knoivn degree-gallon fac- tor. From the total gallons required subtract the total gal- lons of the known factor to find the amount of loater neces- sary to give the reqidred volume. Divide that remainder Digitized by Microsoft® 254 Principles and Practice of Plumbing into the difference between the total degree-gallon require- ment and the knoivn degree-gallon factor. The quotient ivill be the temperature at which the required volume must be to give the resultant temperature required. Example — How much water and at what temperature must be added to 15 gallons of water at 50° to give 30 gallons of water at 110° ? Solution— 30 gals. X 110° (required resultant) =3,300 degree-gallons. 15 gals. X 50° = 750 degree-gallons. (The known degree-gallon factor.) 3,300 — 750 = 2,550 (The required degree-gallon factor.) 30 gals. — 15 gals. = 15 gals. (Required volume.) 15) 2550 (170° = Answer = 15 gallons of water at 170° will, when added to 15 gallons of water at 50°, result in 30 gallons of water at 110°. Example— How much water and at what temperature must be added to 20 gallons of water at 140° to result in a volume of 45 gallons at 100°? Solution— 45 gals. X 100° = 4,500 degree-gallons. 20 gals. X 140° =2,800 degree-gallons. 4,500 — 2,800 = 1,700 degree-gallons. 45 gals. — 20 gals. = 25 gals. 25) 1700 (68° = Answer = 25 gallons of water at 68° added to 20 gallons of water at 140° will result in a volume of 45 gallons of water at 100°. Waterbacks. — The hollow casting forming part of the fire-box lining of kitchen ranges, and through which water circulates and is heated for storage in the range boiler, is commonly known as a waterback. In most waterbacks a horizontal partition, a, Fig. 122, gives the water a positive circulation through the casting and prevents a commingling of waters of different temperatures, as is the case where waterbacks without this partition are used. It is quite important that the opening for the flow pipe, b, be drilled close to the top wall of the casting, so that the hottest water can flow from the waterback and not cause a rattling sound by being retained in the waterback to form steam. Water Heating Coils. — In ranges which are not pro- vided with waterbacks, heating coils are sometimes made to supply the deficiency. Usually they consist of two pieces of one-inch black iron pipe joined at one end by a return bend. The free ends are then extended through the wall of the fire-box, so they can be connected to the boiler. The chief ob.iection to the use of water heating coils is the fact that their effect on the draft of the stove or on the heating Digitized by Microsoft® Principles and Practice of Plumbing 255 capacity of the oven can never be pre-determined, conse- quently ovens are often spoiled for baking purposes by plac- ing a water coil in a range not designed to accommodate one. Capacity of Waterbacks and Coils. — The capacity of waterbacks and coils depends upon the materials of which they are made, the thickness of metal forming their walls, the location of the waterback or coil in the fireplace, their freedom from soot, ashes or incrustation of lime or mag- nesia, and the intensity of the fire to which they are exposed. Under favorable conditions a coil made of copper pipe will transmit 300 B. T. U. per hour, a wrought iron or steel pipe, 200 B. T. U. per hour, a cast iron waterback, 80 B. T. U. per hour per square foot, for each degree Fahrenheit dif- ference in tem- ^^,,^,,^ „„„„^ perature between / ^- — ^ ^^^"^^"^^ — i- the flames or hot gases in contact with the water- back or coil and the water inside. As a matter of fact, however, waterbacks and coils transmit only about 25 per cent, of their possible capac- ity. This is due to the fact that they are placed in the fire- box in the position least likely to affect the stove for other purposes, and therefore are not exposed to the hottest coals and gases of the fire. Furthermore, they are partly covered by ashes, soot and dying coals, and in the case of cast iron waterbacks, the walls usually are of too great thickness to transmit the maximum amount of heat. In many cases waterbacks and coils are coated with incrustations of lime or magnesia that still further reduce their transmitting capacities. New or clear cast iron waterbacks, under ordi- nary conditions, will heat from ordinary temperature to 200 degrees Fahrenheit from 25 to 35 gallons of water per hour for each square foot of exposed surface. With an ordinary fire, one square foot of exposed waterback surface will heat about 25 gallons of water per hour, while with a fire such as Digitized by Microsoft® 256 Principles and Practice of Plumbing is used for baking or roasting, one square foot of surface will heat about 35 gallons of water per hour. However, the average size of waterback contains only 110 square inches or about 2/3 square foot of exposed sur- face, and water for domestic uses is seldom heated to above the temperature of 180 degrees Fahrenheit, therefore an ordinary waterback with an average fire will heat from ordinary temperature to boiling point about 17 gallons of water per hour, or from ordinary temperature to 180 de- grees Fahrenheit about 21 gallons of water per hour, while with a fire such as is used for cooking or baking it will heat 23 gallons of water to the boiling point, or 27 gallons of water to a temperature of 180 degrees Fahren- heit. Wrought iron pipes will heat from 30 to 40 gallons of water un- der the same conditions, and copper pipes will heat from 45 to 60 gallons per hour for each square foot of sur- face exposed to the fire. In calculat- ing the heating capacity of a water- back or coil, the average tempera- ture of the water is taken; thus, if water at 60 degrees Fahrenheit is heated to 200 degrees Fahrenheit, the average temperature of the water would be 60 + 200 ^ 2 = 130 degrees Fahrenheit, and the range of temperature through which it is heated would be 200 — 60 = 140 degrees Fahrenheit. Water Heaters. — A magazine feeding water heater, such as is used for heating large quantities of water in apartment houses, barber shops, bathing establishments, etc., is shown in section in Fig. 123. It consists simply of a combustion chamber surrounded by an annular space through which water circulates and is heated from the flames and hot gases within. Heaters of this type are made having capacities of from 50 to 600 gallons per hour, and larger sectional heaters of different types are made with Fig. 12:1 Wator Heater Digitized by Microsoft® Principles and Practice of Plumbing 257 capacities up to several thousand gallons per hour. The heater shown in the illustration has a magazine feed. This consists simply of a tube in the center of the heater that holds several hours' supply of coal and automatically feeds it to the fire. It can be made into a hand-fired heater by removing the magazine. A magazine feed heater, however, is preferable to a hand feed heater for the reason that it will run for 24 hours if necessary without attention. Capacity of Water Heaters, — The capacity of a water heater depends upon the amount of coal it can effi- ciently burn during a given period of time, and the con- ductivity and thickness of the walls of the fire-box. Boiler iron is a better conductor of heat than cast iron, therefore a boiler iron heater of given surface will heat more water in an hour than will a cast iron heater of equal surface, the- amount of coal burned and the intensity of the fire in both cases being equal. The amount of coal economically burned in a heater depends upon the area of grate and size of the smoke flue. Heaters burn from 3 to 6 pounds and will prob- ably average 4 pounds of coal per hour per square foot of grate surface. The total heat of combustion of a pound of coal of average composition is 14.133 B. T. U. Of this amount, however, a large percentage passes up the chimney as hot gases, so that under ordinary conditions only about 8000 B. T. U. are actually transmitted to the water. There- fore, in calculating the capacity of a heater, the area of grate surface, amount of coal efficiently burned and the available B. T. U. in a pound of coal are the limiting factors. Architects and plumbers should determine for themselves, by calculation, the heating capacity of a heater, and not rely upon manufacturers' ratings. This is made necessary by the lack of uniformity among manufacturers in the rat- ing of their heaters, which differ from one another in some cases over 100 per cent, for equal area of grates. Some part of that percentage might be accounted for by the differ- ence of construction, which gives some heaters greater heat- ing surface than others, but, making due allowance for the improved design of some heaters, they will invariably be found overrated, while the run of heaters are overrated Digitized by Microsoft® 258 Principles and Practice of Plumbing from 20 to 50 per cent. The capacity of heaters can be cal- culated by means of the rule or formulas following : When the quantity of water to be heated per hour is known, the size of grate required can be found by the fol- lowing rule : Rule — Multiply the weight of water in pounds by the number of degrees rise in temperature and divide the product by the number of pounds of coal burned per hour per square foot of grate surface, by the number of heat units transmitted to the water from 1 pound of coal. Tlie result will be the area in square feet of grate required. Expressed as a formula: g= — , in which W = weight in pounds of water to be heated, t = degrees C u Fahr. water is to be raised, C = pounds of coal burned per hour per square foot of grate, u =; units of heat absorbed by water from each pound of coal, g = area of grate in feet. Example — What size of grate will be required to heat 300 gallons of water per hour from 62 to 212 degrees Fahr., 1 gallon weighing 8.3 pounds? „ 300 X 8.3 X (212-62) „ _ ,, . _* a Solution— — — = 7.7 so. it. grate surface. — ^Answer. 6 X 8000 In the above solution 6 pounds of coal was assumed as the consumption per square foot of grate surface because the maximum rating of the heater is desired. The capacity of a water heater of known dimensions can be ascertained by the following rule : Ride — Multiply the consumption of coal per square foot of grate surface by the number of B. T. U. transmitted to the water from each pound, of coal, by the number of square feet of surface in the grate, and divide the product by the weight of 1 gallon of water times the degrees of temperature the water is raised. Expressed as a formula: gcu q = , in which g = size of grale in square I'pfl, c = pounds of coal burned Pt per hour per square foot of gralc surface, u = units of heat absorbed by the water from each pound of coal, p = 8.3 weight of 1 pound of water, t = degrees Fahr. water is raised, q = quantity of water in gallons heated per hour. Digitized by Microsoft® Principles and Practice of Plumbing 259 Example — ^How many gallons of water can be heated from- 62 to 212 degrees Fahr. in a heater with 7.7 square feet of grate surface? 7.7 X 6 X 8000 SOLOTION- 8.3 X (212—62) .= 296.- In selecting a water heater, the time the heater must run on one charge of fuel must be taken into consideration. If a small heater were fired every half-hour with a light charge of coal, it would do as many such heaters are rated to do, furnish a certain specified amount of heat to the water. How- ever, such a heater would be a nuis- ance, and would supply only part of the rated heat if fired only at long intervals, as heaters are supposed to be fired. A ^^^^^Ji heater ought to hold enough coal to burn freely at the greatest rate of combustion it will have to in use, for at least four hours time. As- suming a combustion of six pounds of coal per hour for each square foot of grate surface, and a period of four hours the heater must run on one charge of fuel, then a space sufficient to hold - ^^®> 4 X 6 = 24 pounds of fuel would have to be provided in the combustion chamber for each square foot of grate surface. Anthracite coal weighs 95 pounds per cubic foot, so that a heater ought to have a storage capacity of one-quarter cubic foot for each square foot of grate surface. In addi- tion to this storage capacity for coal the combustion cham- ber must have ample space for the burning of gases distilled from the coal, or the gases will escape without being burned, and the heating capacity will be greatly reduced. The gases cannot burn unless mixed with a large quantity of air, so it would be safe to say that at least one-half cubic Fig. 524 Garbage Burning Water Heater Digitized by Microsoft® 260 Principles and Practice of Plumbing foot of space should be allowed in the fire box, in addition to the space occupied by the coal, for each square foot of grate surface. Garbage Burning Water Heaters. — Garbage burn- ing water heatejrs are sometimes used in large institutions where they serve the double purpose of destroying refuse and heating water for domestic supply. A type of such water heater is shown in Fig. 124. Its distinguishing features are two grates, one an ordinary grate to burn coal or other fuel on, and the other a pipe coil through which water circulates and on which the garbage to be burned is placed. Where large quantities of combustible materials must be disposed of, such heaters are both efficient and economical. Smoke Flues. — It is important that a good chimney flue, straight and smooth inside and proportioned to the area of the grate, be provided for each water heater. No other smoke pipe shoiild be permitted to connect with this flue, nor should other openings to it be permitted, as they would spoil the chimney draft. Smoke flues should be cased with flue linings to give them a smooth interior surface. The best form for flue linings is round or oval, as smoke and hot gases pass up with less frictional resistance in a round flue than in a square one. Square flues are much more efficient than rectangular ones, on account of the less surface ex- posed for a given area of flue; for instance, a flue 12x12 inches has an area of 144 square inches and a perimeter of only 48 inches, while a flue 8x18 inches having an equal area, has a perimeter of 52 inches, thus presenting four additional incheg to offer resistance. No satisfactory Fig. 125 Automatic Waterback Cleaner Digitized by Microsoft® Principles and Practice of Plumbing 261 formula was ever devised to calculate the area of smoke flues under varying conditions. A simple empirical rule that will be found satisfactory for determining the area of flues for water heaters follows : Rule — Allow for smoke flue one-eighth the sectional area of heater grate. Example — ^What size of smoke flue will be required for a water heater containing 4 square feet of grate? Solution — 4 square feet =: 576 square inches. Vs of 576-= 72 square inches z= area of smoke flue. The nearest sizes of commercial flue linings are : Square, 8% X ^Vs inches =: 72.25 square inches round, 10^ times .7584 =: 78.54 square inches. Incrustation of Water Heaters. — An apparatus for automatically feeding soda ash or other precipitating chem- icals to hard water is shown in Fig. 125. This apparatus is used in connec- tion with waterbacks and water heat- ers to prevent them becoming choked by deposits of lime. When properly looked after an apparatus of this kind will precipitate so large a quantity of the lime or magnesia held in solution by the waters, that the periods be- tween cleanings of waterbacks or heaters will be lengthened from 50 to 100 per cent. The precipitating reagents are placed in this vessel, wetted, and the two valves opened sufficiently to give a flow through the apparatus propor- tioned to the amount of water flowing through the pipe. The apparatus then works automatically until the chemical reagent is exhausted. To secure satis- factory results the apparatus must be placed on the return pipe to the waterback, as shown. All water is thus treated before reaching the waterback or heater. Fig. 126 Vertical Tank with Steam Coil Digitized by Microsoft® 262 Principles and Practice of Plumbing Fig. 327 Steam Coil in Iloriontal Tanli Steam Coils. — Water in tanks is sometimes heated by a steam coil immersed in the water. This method of heat- ing has the advantage of requiring no care whatever, and saves the labor, expense and dirt of an extra fire. When exhaust steam is available the cost of heating water by this method is prac- tically nothing. A steam coil can be placed in either a vertical or in a horizontal tank, the only re- quirements being that the pipe used in the coil be large enough to take care of the water of con- densation, and that it have a slight fall from the top con- nection where the steam enters to the bottom outlet towards which the water of condensation drains. In a vertical tank. Fig. 126, the steam coil is spiral and placed near the bottom. This type of coil is used princi- pally in connection with kitchen ranges. Large size hot water tanks are usually placed in a horizontal position. Fig. 127 shows a method of placing a coil for high pressure steam inside of a hot-water tank. In this coil, steam or the condensa- tion, travels through the en- tire length of coil. When ex- haust steam is used, however, a shorter course should be provided to minimize the back pressure on the engines. A heating coil for exhaust steam is shown in Fig. 128. This type of heater is better than a continuous coil, either for exhaust steam or for live" steam. Steam coils for tanks may be made of copper, brass ^£>r/p Pipe. Fig. 128 Exhaust Steam Coil in Tank Digitized by Microsoft® Principles and Practice of Plumbing 263 or iron pipe. Copper and brass pipes last longer than iron and transmit more heat to the water per square foot of heating surface. For these reasons, either copper or brass coils are preferable to iron pipe coils. The size of steam coil in square feet required to heat a certain quantity of water in a given time, can be found by the following rule : Rule — Multiply the weight of water in pounds by the number of degrees temperature Fahrenheit the water is to be raised, and divide the product by the coefficient of trans- mission times the difference between the temperature of the steam and the average temperature of the water. Expressed as a formula: s =z -,,„ — ,. in whicli s = surface of copper or iron pipe in square feet, w = weight ill pounds of water to be heated, r = rise in temperature of water, t =: average temperature of the water in contact with coils, T = temperature of steam, c = coefficient of transmission. The value of c for copper is 300 B. T. U. and for iron 200 B. T. U. transmitted per hour per square foot of sur- face for each degree difference between the temperature of the steam and the average temperature of water. In computing the heating surface of copper or iron pipe in steam coils, the inner circumference of the pipe must be taken, as that is the real heating surfa,ce to which heat is applied. The average temperature of the water in contact with the coil is taken as the temperature of the water. Example — How many square feet of heating surface will be required in a copper coil to heat 300 gallons of water per hour from 50 degrees to 200 degrees Fahr. with steam 15 pounds pressure? Solution— 300 X 8.3 = 2490 pounds of water to be heated. 200° — 50° =: 150° = rise in temperature of water. 150° -=- 2 + 50° = 125° = average temperature of water. 250° = temperature of steam at 15 pounds gauge j'ress- ure (Table LXIX). 250° — 125° = difference between temperature of steam and average temperature of water. Substituting these values in the formula: 2490 X 150 „ „ i- , ' f ., ■ s = — ^ = 9.9 square leet or coil. Answer. 300 X (250—125) Some convenient constants for steam coils that produce approximations sufficiently accurate for most purposes fol- low. The values will be found safe : Digitized by Microsoft® 264 Principles and Practice of Plumbing W = gallons water to heat per hour. W -^ 10 r= square feet iron pipe coil required for exhaust steam. W ^ 15 = square feet copper coil required for exhaust steam. W X .07 = square feet iron pipe coil for 5 pounds pressure steam. W X -045 = square feet copper pipe coil for 5 pounds pressure steam. W X -05 = square feet iron pipe coil for 25 pounds steam pressure. W X -035 — square feet copper pipe coil for 25 pounds steam pressure. W X .04 = square feet iron pipe coil for 50 pounds steam pressure. W X -025 = square feet copper pipe coil for 50 pounds steam pressure, W X .03 = square feet iron pipe coil for 75 pounds steam pressure. W X .02 = square feet copper pipe coil for 75 pounds steam pressure. W -^ 30 = horse-power of boiler to supply steam. W -f- 7 rz: pounds of coal per hour to heat water. W-^ 200 = tank heater grate area (not less 12 inches diam.). W -=- 30 = square feet heating surface in tank heater. Condensation from steam heating coil = 1 pound of steam per gallon of water heated per hour = 1000 heat units. Increased weight or pounds of steam blown into water =^ units of heat ^1000. Increase in gallons = units of heat X 0.00012. The above data apply to closed tanks. For open kettles there is a large loss of heat by evaporation from the surface of the water. With a closed tank there is a loss of about 200 units per hour per square foot of exposed surface. Taking the foregoing example for comparison, the near- est value to 15 pounds steam is 25 pounds, and the coefficient for copper pipe at this temperature is .035. Hence, 300 + .035 = 10.5 square feet. Answer. Example — What size steam coil is required to heat 300 gallons per hour in a closed boiler with exhaust steam? 300-^ 10^ 30 square feet in coil. With steam at 25 pounds pressure? 300-X 0-07 = 21 square feet. How many pounds of steam will be required? 300 pounds (1 pound per gallon) . What horse-power steam boiler will be required? 300-^30=: 10 horse- power. How many pounds of poal per hour? 300 -H 7 = 43 pounds. What size tank heater is required (grate area in square feet) ? 300 -=- 200 ^1% square feet = about 17 inches diameter. Actual Performance of Steam Water Heaters. — In the Unioii Central Office Building, Cincinnati, Ohio, ar^ Digitized by Microsoft® Principles and Practice of Plumbing 265 three Goubert heaters for heating the water throughout the building. Hot water being used only at lavatories and slop sinks. Water enters the heater* at a temperature of 72 degrees Fahrenheit, and the average temperature of the water delivered throughout the 30 stories of the building is 138 degrees F. There are in the building approximately 275 lavatories and slop sinks or fixtures supplying hot water to the tenants. During the eight hours of the test it was estimated that 2494 pounds of steam were used in heating water for the building, or an average of 311.8 pounds per hour. The cost of producing hot water for eight hours was $0.2961, making the cost per hour $0,037. The cost of heating water per fixture per day averaged about $0.00108. Heating Water by Steam in Contact. — The quick- est and most economical way to heat water with steam is to bring -the steam into direct contact with the water. This method is used extensively to heat water in swimming pools, vats for industrial purposes, dish washing, etc., and is usually accomplished by forcing steam through a perforated pipe or steam nozzle located near the bottom of the tank and submerged by the water. When perforated pipes are used for this purpose they should be of brass or copper to pre- vent corrosion, and the combined area of the perforations should be at least eight times the area of pipe to equal it in capacity. Exhaust steam from pumps, engines or other apparatus, that is liable to contain oil or grease, is not suit- able for this purpose. When steam is brought in contact with water in an open vessel steam bubbles are formed, rise toward the sur- face and collapse with a report. For this reason water is heated by steam in direct contact through perforated pipes only when noise is not objectionable. Noiseless Water Heaters. — A steam nozzle for noise- lessly heating water by steam in direct contact is shown in Fig. 129. This apparatus consists of an outward and upward discharging steam nozzle covered by a shield which has numerous openings for the admission of water, so that Digitized by Microsoft® 266 Principles and Practice of Plumbing the jet takes the form of an inverted cone, discharging upwards. Air, admitted through a small pipe, is drawn in by the jet, and by mixing with the steam prevents the sudden col- lapse of bubbles and the consequent noise which is such a great objection to heating by direct steam in the old way. A valve or cock on this air pipe regulates the air to the quantity most desirable. If water is to be heated to a less tem- perature than 165 degrees Fa h r e n h e i t, which would be the case in most installa- tions, the air pipe is not used, as the heater will operate noiselessly without it. If, however, the temperature of the water is to be raised above 165 degrees Fahrenheit an air pipe must be used. A pressure of air is not required in the air pipe when the pressure of steam is sufficient to draw air in by inspiration. The pressure of steam required for this purpose is proportioned to the depth of water above the heater in the tank, and cannot be less than those given in Table LXVI. TABLE LXVI. Pressures of Steam for Heads of Water Fig. 129 Steam Water Heater Head of water in feet above heater. Minimvim steam pressure, pounds.. 3 4 5 (i 7 8 9 10 4 8 12 18 24 32 40 50 If water is to be heated to a greater temperature than 165 degrees Fahrenheit with less steam pressure than is called for in the foregoing table, air must be supplied under pressure, and both the air pressure and the steam pressure Digitized by Microsoft® Principles and Practice of Plumbing 267 must equal in pounds the height in feet of water above the heater. Stock sizes of this type of heater, with the manufac- turers' ratings in B. T. U. per minute under different steam pressures, can be found in Table LXVII. TABLE LXVII. Capacity of Noiseless Water Heaters Diameter Diameter Capacity in Heat Units (B. T. U.) per Minute of of Steam Pressure Steam Pipe Air Pipe in Inches in Incites 10 Pounds 20 Pounds 40 Pounds 60 Pounds 80 Pounds M Vi 810 1,040 ' 1,820 2,485 2,920 y-i M 2,540 3,270 5,720 7,620 9,150 Vi M 4,375 5,625 9,845 13,125 15,760 1 % 7,000 9,000 15,750 21,000 25,200 W2 Yi 17,500 22,500 39,300 52,500 73,000 2 Va. 26,700 34,300 60,100 80,000 96,000 2}^ Yi 39,000 50,500 88,500 108,000 141,500 3 1 61,200 78,750 137,5C0 183,700 215,500 4 iM 103,250 132,750 231,200 309,750 371,700 6 2 245,000 315,000 550,000 735,000 862,000 To find the size of heater required to heat a certain quantity of water in a given time, first find the number of B. T. U. required per minute and the pressure of steam and the size will be found in Table LXVII. Example — 100 cubic feet of water shall be heated from 60 to 180 degrees, or 120 degrees increase, in 30 minutes, with steam of 80 lbs. pressure. Weight of 1 cubic foot of water, 62.5 pounds. 62.5X100X120 _ 750,000 30 30 ;= 25,000 heat units per minute. Comparing this with table indicates the 1-inch steam pipe is the size required. Another Example — 200 gallons of wau-r shall be licalcd from 30 degrees to 90, or 60 degrees increase, in six minutes by steam of 10 pounds pressure. Weight of 1 gallon, 8.3 pounds. 8.3X200X60_ 99,600 ,,,„„ i , ■, — ~ — = — = lo,o0U heat units per niinu e. 6 6 Comparing this with the table indicates that li/^-inch steam pipe is the size required. Digitized by Microsoft® 268 Principles and Practice of Plumbing COMMINGLER. — An apparatus for noiselessly heating water by direct contact in a closed circuit is shown in Fig. 130. This apparatus is known as a commingler, and takes the place of, and is connected to, a storage tank in the same manner as a waterback or heater. Water from the hot water tank enters the commingler through the pipe a, passes up through the body of the casting and flows back through the pipe b into the tank. Steam is supplied to the heater through the pipe c, passes down pipe d, and escapes into the body of the commingler through the small holes, e, shown in the nozzle. The admission of steam to the body of the water in this manner prevents the noise which is experienced when steam enters a body of cold water directly and with- out being previously broken up, as is done by these holes. Sometimes a portion of the interior of the casting is filled with small pebbles surround- ing the nozzle, the effect being to still further break up the steam, which has to force its way through these pebbles be- fore striking the main body /~TT-^ of water in the casting. i=L J=i ^ To use this apparatus in a closed circuit the steam pressure must be greater than the water pressure, and a check-valve should be placed in the steam pipe to prevent water flowing from the commingler to the steam boiler when the steam pressure is low. Heat Transmitted by Steam to Water. — ^When steam is brought in contact with water of lower temperature than the steam, it almost instantly parts y/i\h all of its latent heat and all of its sensible heat above the temperature Qt tJie water. Thus, whpn ^ poun^ of strain i§ brought in Fig. 130 Steam and Water Commingler Digitized by Microsoft® Principles and Practice of Plumbing 269 contact with water it imparts as many B. T. U. to the water as there are B. T. U. in a pound of steam at that pressure above the temperature of the water. For instance, there TABLE LXVIII. B. T. U. in Water at Different Tempera- tures Temperature, Degrees Fahr. Number of B. T. U. reckoning from 0° Number of B. T. U. Required to raise the Tempera- ture of the Water to Boiling Point 212° Fahr. 35. . . . 35.000 40.001 45.002 50.003 55.006 60.009 65.014 70.020 75.027 80.036 85.045 90.055 95.067 100.080 105.095 110.110 115.129 120.149 125.169 130.192 135.217 140.245 145.275 150.305 155.339 160.374 165.413 170.453 175.497 180.542 185.591 190.643 195.697 200.753 205.813 210.874 177.900 40 172.899 45 167.898 50 162.897 55 157.894 60 65 70 75 80 85 90 95 100 105 110 152.891 147.886 142.880 137.873 132.864 127.855 122.845 117.833 112.820 107.815 102.790 115 97.771 120 92.751 125 87.731 130 82.708 135 •. 77.683 140 72.655 145 67.625 150 62.585 57.561 160. ... 52.526 47.487 170. ... 42.447 37.403 32.358 185 . 27.309 22.257 195 17.203 200 ... . 12.147 205 7.087 2.016 Digitized by Microsoft® 270 Principles and Practice of Plumbing are 1141.1 B. T. U. in one pound of steam at atmospheric pressure reckoning from the freezing point, and if allowed to expand in water with a temperature of 60 degrees Fahrenheit, the steam will part with all of its heat until the temperature of the water of condensation is equal to the temperature of the water to be heated. In doing so it will impart 1141.1 + 32 — 60 = 1113.1 B. T. U. to the water, and will increase its bulk by one pound, or about l^ gallon. The number of B. T. U. in a pound of steam varies with its temperature and pressure. The number of B. T. U. contained in one pound of water at different temperatures, also the number of B. T. U. required to raise one pound of water from different temper- atures to boiling point at atmospheric pressure, may be found in Table LXVIII. Steam Required i'o Heat Water. — The weight of steam required to heat a given quantity of water from a cer- tain temperature to boiling point can be found by the fol- lowing rule : Rule — Multiply the number of pounds of water to be heated by the number of degrees temperature the water is to be raised, and divide the product by the total heat of steam at the pressure it iti to be 7tsed, less the sensible heat at atmospheric pressure. This may be expressed by the formula : w h ^ 1 in which s = weight of steam in pounds, w =:z pounds of water to be heated, h = degrees Fahr. water to be lieated; L = total heat of steam at pressure used, 1 = sensible heat at atmospheric pressure. Example — How many pounds ol steam at 70 pounds pressure will be required to heat 7,500 pounds of water from 48 degrees Fahr. to boiling point? Solution— l^^^^^t^^l = 1237 pounds of steam. Answer. (1174 — 180) An empirical rule that is sufficiently approximate for most purposes is to allow 1 pound of steam for 6 pounds of water to be heated. Taking the above example then : 7500 -^ 6 = 1250 pounds of steam. Answer. Digitized by Microsoft® Principles and Practice of Plumbing 271 TABLE LXIX. Properties of Saturated Steam. Heat Units above 32 Degrees Fahr. Weight Volume Absolute Tempera- ture Degrees Contained in 1 Pound of Steam of 1 Cubic Foot of 1 Pound Pressure in Fahr. In Water Latent Total in Cubic Heat Heat Pounds Feet 14.7 212.0 180.9 965.7 1146.6 .0379 26.37 15 213.1 181.6 965.3 1146.9 .0387 25.85 16 216.3 184.9 963.0 1147.9 .0411 24.33 17 219.5 188.1 960.8 1148.9 .0435 22.98 18 222.4 191.1 958.7 1149.8 .0459 21.78 19 225.3 193.9 956.7 1150.6 .0483 20.70 20 228.0 196.7 954.8 1151.5 .0507 19.73 21 230.6 199.3 953.0 1152.3 .0531 18.84 22 233.1 201.8 951.2 1153. a .0554 18.04 23 235.5 204.3 949.5 1153.8 .0578 17.30 24 237.8 206.6 947.9 1154.5 .0602 16.62 25 240.1 208.9 946.3 1155.2 .0625 16.00 26 242.2 211.1 944.7 1155.8 .0649 15.42 27 244.3 213.2 943.3 1156.5 .0672 14.88 28 246.4 215.3 941.8 1157.1 .0695 14.38 29 248.4 217.3 940.4 1157.7 .0719 13.91 30 250.3 219.3 939.0 1158.3 .0742 13.48 31 252.2 221.2 937.7 1158.9 .0765 13.07 32 254.0 223.0 936.4 1159.4 .0788 12.68 33 255.8 224.8 935.1 1159.9 .0812 12.32 34 257.5 226.6 933.9 1160.5 .0835 11.98 35 259.2 228.3 932.7 1161.0 .0858 11.66 36 260.9 230.0 931.5 1161.5 .0881 11.36 37 262.5 231.6 930.4 1162.0 .0904 11.07 38 264.1 233.3 929.2 1162.5 .0927 10.79 39 265.6 234.8 928.1 1162.9 .0949 10.53 40 267.2 236.4 927.0 1163.4 .0972 10.28 41 268.7 237.9 926.0 1163.9 .0995 10.05 42 270.1 239.4 924.9 1164.3 .1018 9.83 43 271.6 240.8 923.9 1164.7 .1041 9.61 44 273.0 242.3 922.9 1165.2 .1063 9.40 45 274.3 243.7 921.9 1165.6 .1086 9.21 46 275.7 245.1 920.9 1166.0 .1109 9.02 47 277.0 246.4 920.0 1166.4 .1131 8.84 48 278.3 247.7 919.1 1166.8 .1154 8.67 49 279.6 249.1 918.1 1167.2 .1177 8.50 50 280.9 250.3 917.3 1167.6 .1199 8.34 51 282.2 251.6 916.4 1168.0 .1222 8.19 52 283.4 252.9 915.5 1168.4 .1244 8.04 53 284.6 254.1 914.6 1168.7 .1267 7,89 54 285.8 255.3 913.8 1169.1 .1289 7,76 55 287.0 256.5 912.9 1169.4 .1312 7,62 56 288.1 257.7 912.1 1169.8 .1334 7,50 57 289.3 258.9 911.3 1170.2 .1357 7.37 58 290,4 260.0 910.5 1170.5 .1379 7.25 59 291.5 261,1 909.7 1170.8 .1401 7.14 60 292.6 262,3 908.9 1171.2 ,1424 7,02 Digitized by Microsoft® 272 Principles and Practice of Plumbing TABLE LXIX— Continued Heat Units above 32 Degrees Fahr. Weight Volume Absolute Tempera- ture Degrees Contained in 1 Pound of Steam of 1 Cubic Foot of 1 Pound Pressure in Fahr. In Water Latent Total in Cubic Heat Heat Founds Feet 61 293.7 263.3 908.2 1171.5 .1446 6.92 62 294.7 264.4 907.4 1171.8 .1468 6.81 63 295.8 265.5 906.6 1172.1 .1491 6.71 64 296.8 266.6 905.9 1172.5 .1513 6.61 65 297.8 267.6 905.2 1172.8 .1535 6.52 66 298.8 268.7 904.4 1173. 1 .1557 6.42 67 299.8 269.7 903.7 1173.4 .1579 6.33 68 300.8 270.7 903.0 1173.7 .1602 6.24 69 301.8 271.7, 902.3 1174.0 .1624 6.16 70 302.8 272.7 901.6 1174.3 .1646 6.08 71 303.7 273.6 901.0 1174.6 .1668 6.00 72 304.7 274.6 900.3 1174.9 .1690 5.92 73 305.6 275.6 899.6 1175.2 .1712 5.84 74 306. S 276.5 898.9 1175.4 .1734 5.77 75 307.4 277.4 898.3 1175.7 .1756 5.69 76 308.3 278.4 897.6 1176.0 .1778 5.62 77 309.2 279.3 897.0 1176.3 .1800 5.56 78 310.1 280.2 896.3 1176.5 .1822 5.49 79 311.0 281.1 895.7 1176.8 .1844 5.42 80 311.9 282.0 895.1 1177.1 .1866 5.36 81 312.7 282.8 894.5 1177.3 .1888 5.30 82 313.6 283.7 893.9 1177.6 .1910 5.24 83 314.4 284.5 893.3 1177.8 .1932 5,18 84 315.3 285.4 892.7 1178.1 .1954 5.12 85 316.1 286.2 892.1 1178.3 .1976 5.06 86 316.9 287.1 891.5 1178.6 .1998 5.01 87 317.7 287.9 890.9 1178.8 ,2020 4,95 88 318.5 288.8 890.3 1179.1 .2042 4.90 89 319.3 289.6 889.7 1179.3 .2063 4,85 90 320.1 290.4 889.2 1179.6 .2085 4,80 91 320.9 291.2 888.6 1179.8 .2107 4,75 92 321.7 291.9 888.1 1180.0 ,2129 4,70 93 322.4 292.8 887.5 1180.3 .2151 4,65 94 323.2 293.5 887.0 1180.5 ,2173 4.60 95 323.9 294.3 886.4 1180.7 ,2194 4.56 96 324.7 295.1 885.9 1181.0 ,2216 4,61 97 325.4 295.8 885.4 1181,2 .2238 4,47 98 326.2 296:6 884.8 1181,4 .2260 4,48 99 326.9 297.3 884.3 1181.6 .2281 4,38 100 327.6 298.1 883.8 1181.9 .2303 4.34 101 328.3 298.8 883.3 1182.1 .2325 4.30 102 329.1 299.6 882.7 1182.3 .2346 4,26 103 329.8 300.3 882.2 1182.5 .2368 4,22 104 330.5 301.0 881.7 1182.7 .2390 4,19 105 331.2 301.7 881.2 1182.9 .2411 4,15 106 331.9 302.4 880.7 1183.1 .2433 4.11 107 332.6 303.2 880.2 1183,4 .2455 4.07 Digitized by Microsoft® Principles and Practice of Plumbing TABLE LXIX— Continued 273 Heat Units above 32 Degrees Fahr. Weight Volume Absolute Tempera- ture Degrees Contained in 1 Pound of Steam of 1 Cubic Foot of 1 Pound Pressure in Fahr. In Water Latent Total in Cubic Heat Heat Pounds Feet 108- 333.2 303.9 879.7 • 1183.6 .2476 4.04 109 ' 333.9 304.6 879.2 1183.8 .2498 4.00 no 334.6 305.3 878.7 1184.0 .2519 3.97 111 335.3 305.9 878.3 1184.2 .2541 3.94 112 335.9 306.6 877.8 1184.4 .2563 3.90 113 336.6 307.3 877.3 1184.6 .2584 3.87 114 337.2 308.0 '876.8 1184.8 .2606 3.84 115 337.9 308.6 876.4 1185.0 .2627 3.81 116 338.5 309.3 875.9 1185.2 .2649 3.78 117 339.2 310.0 875.4 1185.4 .2670 3.75 118 339.8 310.6 875.0 1185.6 .2692 3.72 119 340.4 311.3 874.5 1185.8 .2713 3.69 120 341.1 311.9 874.1 1186.0 .2735 3.66 121 341.7 312.5 873.6 1186.1 .2757 3.63 122 342.3 313.1 873.2 1186.3 .2778 3.60 123 342.9 313.8 872.7 1186.5 .2799 3.57 124 343.5 314.4 872.3 1186.7 .2821 3.55 125 344.1 315.1 871.8 1186.9 .2842 3.62 126 344.7 315.7 871.4 1187.1 .2864 3.49 127 345.3 316.3 871.0 1187.3 .2885 3.47 128 345.9 316.9 870.5 1187.4 .2907 3.44 129 346.5 317.5 870.1 1187.6 .2928 3.42 130 347.1 318.1 869.7 1187.8 .2950 3.39 131 347.7 318.7 869.3 1188.0 .2971 3.37 132 348.3 319.3 868.9 1188.2 .2992 3.34 133 348.9 319.9 868.4 1188.3 .3014 3.32 134 349.4 320.5 868.0 1188.5 .3035 3.30 135 350.0 321.1 867.6 1188.7 .3057 3.27 136 350.6 321.7 867.2 1188.9 .3078 3.25 137 351.1 322.3 866.8 1189.1 .3099 3.23 138 351.7 322.8 866.4 1189.2 .3121 3.20 139 352.3 323.4 866,0 1189.4 .3142 3.18 140 352.8 324.0 865.6 1189.6 .3163 3.16 141 353.4 324.6 865.1 1189.7 .3185 3.14 142 353.9 325.1 864.8 1189.9 .3206 3.12 143 354.5 325.7 864.4 1190.1 .3227 3.10 144 355.0 326.2 864.0 1190.2 .3249 3.08 145 355.6 326.8 863.6 1190.4 .3270 3.06 146 356.1 327.4 863.2 1190.6. .3291 3.04 147 356.6 327.9 862.8 1190.7 .3313 3.02 148 357.2 328.5 862.4 1190.9 .3334 3.00 149 357.7 329 862.0 1191.0 .3355 2.98 150 358.2 329.6 861.6 1191.2 .3376 2.96 160 363.3 334.9 857.9 1192.8 .3689 2.79 170 368.2 339.9 854.4 1194.3 .3801 2.63 180 372.9 344.7 851.0 1195.7 .4012 2.49 190 377.4 349.3 847.7 1197.0 .4223 2.37 200 381.6 353.7 844.6 1198.3 .4433 2.26 Digitized by Microsoft® 274 Principles and Practice of Plumbing TABLE LXX. Properties of Saturated Steam of from 32 Degrees to 212 Degrees Fahr. at Pressures Under One Atmosphere Total Heat of Pressure One Pound Weight Vnliitn** rtf Tempera- Reckoned of One ture from Water at 100 Cubic Pound of Degrees 32 Degrees Feet Vapor Cubic Feet Fahr. Inches of Pounds per Fahr. Pounds ' Mercury Square Inch Units 32 .181 .089 1091.2 .031 3226 35 .204 .100 1092,1 .034 2941 40 .248 .122 1093,6 .041 2439 45 .299 .147 1095.1 .049 2041 50 .362 .178 1096.6 .059 1695 55 .426 .214 1098.2 .070 1429 60 .517 .254 1099,7 .082 1220 65 .619 .304 1101.2 .097 1031 70 .733 .360 1102.8 .114 877.2 75 .869 .427 1104.3 .134 746.3 80 1.024 .503 1105.8 .156 641.0 85 1.205 .592 1107,3 .182 549.5 90 1.410 .693 1108.9 .212 471.7 95 1.647 .809 1110.4 .245 408.2 100 1.917 .942 1111.9 .283 353.4 105 2.229 1.095 1113,4 .325 307.7 110 2.579 1.267 1115.0 .373 268.1 115 2.976 1.462 1116.5 .426 234.7 120 •i 3.430 1.685 1118.0 .488 204.9 125 3.933 1.932 1119.5 .554 180.5 130 4.509 2.215 1121.1 .630 158.7 135 5.174 2.542 1122.6 .714 140.1 140 5.860 2.879 1124. 1 .806 124.1 145 6.662 ::i.273 1125.6 .909 110.0 150 7.548 3.708 1127.2 1.022 97.8 155 8.535 4.193 1128.7 1.145 87.3 160 9.630 4.731 1130,2 1.333 75.0 165 10,843 5.327 1131.7 1.432 69.8 170 12.183 5.985 1133,3 1.602 62.4 175 13.654 6,708 1134,8 1.774 56.4 180 15.291 ,7.511 1136.3 1.970 50.8 185 17.044 8.375 1137,8 2 , 181 45.9 190 19.001 9.335 1139,4 2,411 41.5 195 21.139 10,385 1140.9 2,662 37.6 200 23.461 11,526' 1142.4 2.933 34,1 205 25.994 12.770 1143.9 3.225 31.0 210 28.753 14,126 1145.5 3.543 28.2 lil2 29.922 14,700 1146,1 3,683 27,2 Digitized by Microsoft® Principles and Practice of Plumbing 275 The temperature of steam at different pressures can be found in Table LXIX. To use this table, add 14.7 to the reading of the gauge to get absolute pressure; the quantities desired will be opposite this figure. Usually 15 pounds added to the gauge pressure to get the absolute pressure will be sufficiently accurate for all ordinary purposes. In the foregoing table the properties of saturated steam are given for pressures above atmosphere, or for gauge pressures. In Table LXX, on the other hand, will be found the properties of saturated steam at less than atmospheric pressures, or at partial vacuums. Booster Heaters. — A higher temperature is some- times required for water in a building for some particular purpose, than is needed, for the entire building. In such cases a booster heater can be used to heat the water for the special purposes. This is done by passing the hot water through a heater with steam coil, thereby raising the tem- perature of the hot water to the required degree. There are no cold water connections to a booster. Heating Water with Gas Kinds of Gas. — There are four different kinds of gas which are used for water heating. They are coal gas, oil gas, water gas,' and natural gas. Acetylene gas and pro- ducer gas are not considered here. Coal gas is produced by the distillation or driving off of the light hydrocarbons, or gas, from coal. Nothing is added to the gas, and the by- products of distillation are coke, tar and ammonia. There is very little coal gas used now commercially. Oil gas is made in much the same manner as coal gas, by the process known as destructive distillation. This con- sists of heating the oil to a very high temperature, thereby causing the heavy hydrocarbons to break up into the lighter or gaseous form. Animal and vegetable fats and oils, waste fats that occur in the manufacture of woolens, and ordinary rosins are used as well as petroleum in the manufacture of oil gas. Digitized by Microsoft® 276 Principles and Practice of Plumbing Water gas, which is probably more extensively manu- factured than any other kind of gas for general distribu- tion, is made commercially by the contact of steam with incandescent carbon in the form of anthracite coal or coke. The steam is decomposed, the hydrogen being separated from the oxygen. The oxygen then takes up carbon from the coal or coke. This gas would burn with a non-luminous flame and would be useless for lighting except with incandescent mantels, so in practice the water gas is enriched with oil gas which furnishes the hydrocarbon necessary to make a luminous flame, but adds very little to the heating quality of the gas. The illuminating power of gas is determined by its candlepower. The candlepower is measured while the gas is burning in an open burner at the rate of five cubic feet per hour, by comparing the light given off with that of a standard candle. A standard candle is one that will burn 120 grains of spermaceti per hour. As a standard of quality, the candle power of gas is giving way to the more rational one of heat value, gas being used now almost exclusively for heating, not for lighting. Heat Units in Gas. — There is no one definite number of heat units, B. T. U., that can be given as the heat value of gas. As has already been pointed out, there are three processes of manufacture of artificial gas, also natural gas, all of which are used throughout the country. Of the man- ufactured gases, two or more kinds are sometimes com- bined, as, for instance, when oil gas is added to water gas, so that the exact amount of heat given off by a cubic foot of gas will depend upon the standard of the local gas company, which should be taken into account when computing the amount of water that can be heated by gas in that locality. Artificial gas is generally said to contain 700 heat units, and natural gas from 740 to 1117 heat units, according to the territory where the natural gas is produced. As a matter of fact, the heat contained in manufactured gas varies from 500 to 600 B. T. U. It seldom exceeds 650. It is governed by laws in some states, and the present Digitized by Microsoft® Principles and Practice of Plumbing 277 tendency seems towards establishing a standard of 525 B. T, U. per cubic foot of manufactured gas. Automatic Water Heaters,* — A thorough under- standing of what is meant by the rated capacity of a heater must be had before an intelligent selection of size can be made. Every instantaneous automatic and multi-coil storage heater has a definite rated capacity, which expresses in the case of the instantaneous automatic water heater the num- ber of gallons per minute, and in the multi-coil storage heater the number of gallons per hour, that the heater will deliver at any given rise in temperature with its normal gas consumption. For the sake of convenience the heaters have generally been numbered to correspond to the number of gallons they will deliver, raising the temperature 63° F. Therefore, a No. 4 heater has a rated capacity at 63° rise in temperature of 4 gallons per minute, but should the required rise be 80° instead of 63°, the rated capacity of a 4-gallon heater would be 3.15 gallons instead of 4 gallons, while if the required temperature rise be only 50°, the rated capacity of the 4-gallon heater would be 5.04 gallons per minute. In the case of the multi-coil storage heater, the rated capacity of the No. 200 heater at 63° temperature rise is 200 gallons per hour, while if the required temperature rise be 80°, the rated capacity will be 157 gallons per hour, but should the temperature rise required be only 50°, the rated capacity would be 252 gallons per hour. The above is based upon the consumption of 1 cubic foot of gas having a heat value of 650 B. T. U. for each gallon of water raised 63°. A rule by which the rated capacity of any instantaneous automatic or multi-coil storage heater for any given tem- perature rise may be found is as follows : Rule— Multiply the size of the heater by 63, the result of which will be the degree-gallon capacity of the heater; divide this result by the number of degrees the temperature is to be raised and the result will be th§ fated; capacity of tpstft ppjppiied by ABierif»B (Jss AsgociatipR, Digitized by Microsoft® 278 Principles and Practice of Plumbing For convenience, the the heater at that temperature rise formula would be as follows : Size number X 63 „ , . r , ;p : ; j = Rated capacity oi heater. lemperature rise in degrees From this it follows that if the required flow and tem- perature raise is known, by the use of the following for- mula the size number of the heater may be determined. Flow X temperature rise 63 = size number of heater. For example: If it is required to deliver 4.50 gallons per minute with a temperature rise of 90° 4 50 X 90 63 : 6.43. Therefore, the size heater to be used in this case would be an 8-gallon per minute heater, since the result is greater than a No. 6, and less than a No. 8, the next larger size. Where heaters are not numbered as described above the rated capacity should be ascertained and this quantity sub- stituted for the size number in the above formula. If the rated capacity is not given as at 63°, the degree rise given should be substituted also. Table LXXI shows the sizes manufactured in the in- stantaneous automatic water heater and Table LXXII the TABLE LXXI. Capacities of Instantaneous Automatic Water Heaters Temperature rise in Degrees Gala. per mm. 50 60 70 80 90 100 110 120 130 140 0.68 150 VA 1.89 1.57 1.35 1.18 1.05 0.95 0.86 0.78 0.73 0.63 2V. 3.15 2.62 2.25 1.97 1.75 1.58 1.43 1.31 1.21 1.12 1.05 3 3.78 3.15 2.70 2.36 2.10 1.89 1.72 1.58 1.45 1.35 1.26 4 5.05 4.20 3.60 3.15 2.80 2.52 2.29 2.10 1.94 1.80 1.68 6 7.58 6.30 5.40 4.73 4.20 3.87 3.52 3.23 2.98 2.76 2.58 8 10.10 8,40 7.20 6.30 5.60 5.04 4.59 4.20 3.88 3.60 3.36 Note — In some cases makers of heaters do not number tlieir heaters as above, but slate llii' capacity of the heaters in the catalogs. In those cases substitute the per minute (Myacily .Tt CiS" rise for the maker's number to use this table. Digitized by Microsoft® Principles and Practice of Plumbing 279 multi-coil storage heater, together with their capacities per minute and per hour respectively, at various temperature rises. TABLE LXXII. Capacities of Multi-Coil Storage Heaters Temperature rise in Degrees Gals. per hour so 60 70 80 90 100 no 120 130 140 ISO 100 126 105 90 78.8 70 63 57.2 52.5 48.4 45 42 200 252 210 180 157.5 140 126 114.5 105.0 97.0 90 84 300 378 315 270 236.0 210 189 172.0 158.0 145.0 135 126 400 505 420 360 215.0 280 252 229.0 210.0 194.0 180 168 500 630 525 450 394.0 350 315 287.0 262.0 242.0 225 210 Note — Where heaters are not numbered according to gallons per hour at C.'!'' rise, substitute the rating for the size number to use this table. It will be noted from the foregoing that it is a funda- mental mistake to believe that there is but one rated capac- ity for each heater, and that it is expressed by the size num- ber of the heater and that it applies for any rise of tempera- ture. As the temperature of the water is increased, the per minute capacity of the heater is correspondingly less, and it will be noted from the table that when an unusually high temperatu]?e is desired, the capacity of the heater is very considerably reduced. Since the greater number of automatic water heaters are installed in residences, the following recommendations, based on general practice, may be used as a guide in deter- mining the proper size heater to install in different size residences : 3-gallon per minute heater or 40-gallon multi-coil stor- age syst«m — Residences having one bath-room and kitchen sink, small family. 4-gallon per minute heater or 50-gallon multi-coil stor- age system — Residences having- one private bath-room, serv- ants' bath-room, kitchen sink, laundry trays. 6-gallon per minute heater or 66 or 80-gallon multi-coil storage system — Residences having two private bath-rooms, servants' bath, one or two bedroom lavatories, kitchen sink and laundry trays. Digitized by Microsoft® 280 Principles and Practice of Plumbing 8-gallon per minute heater or 100-gallon multi-coil stor- age system — Residences having three or four private baths, servants' bath-room, two or three bedroom lavatories, kitchen and pantry sinks, large laundry. Comparatively small family. Due to the large per minute gas requirements for the 8-gallon per minute heater, it is frequently found more desirable, especially in houses of great length, to supply a 3- or 4-gallon per minute heater for the supply of hot water for the entire laundry and kitchen, and install a 6-gallon per minute heater for the supply of water to various bath-rooms of the huse. 100-gallon per hour heater with 100, 120 or 150-gallon tanks — Large residences having three to five bath-rooms, bath-room lavatories, large kitchen sink, pantry sink and laundry. Flat buildings with six apartments of four or five rooms each. 200-gallon per hour heater with 120, 150 or 250-gallon tanks — Large residences having seven to ten bath-rooms, large kitchen sink, pantry sink, dishwashing machine, large laundry. Apartment buildings having ten to fourteen flats of five or six rooms each. 300-gallon per hour heater with 250, 300 or 365-gallon tanks — Large residences having seven to ten bath-rooms, large kitchen sink, pantry sink, dish washing machine, large laundry. Apartment buildings having ten to fourteen flats of five or six rooms each. 400-gallon per hour heater with 365 or 425-gallon tanks — Large apartment buildings having fourteen to twenty-five flats of five, six or seven rooms. Very large city homes. Thirty to fifty-room hotels. 500-gallon per hour heater with 425, 500 or 600-gallon tanks — Apartment buildings having twenty to thirty flats of five, six or seven rooms each. Very large city homes. Forty to sixty-room hotels. Larger requirements may be met by using what are known as duplex storage systems, in which' two or more multi-coil storage heaters are connected to a single tank of proper storage capacity. Digitized by Microsoft® Principles and Practice of Plumbing 281 While the above table may be used as a guide, unusual conditions may make it necessary to depart from it. The street main and the service from the main to the meter must be of sufficient size to supply the maximum demands of the heater. The gas supply should be run direct from the meter to the thermostat without any branches, and should be large enough for the maximum amount of gas required by the heater. As in the case of the instantaneous automatic water heater, a tag should be attached to the meter, stating that a multi-coil storage system is installed. The size of gas pipe, meter, and flue for automatic gas heaters can be found in Table LXXIII. TABLE LXXIII. Size of Pipes for Automatic Steerage Systems Size of Water Supply Water Supply! Gas Meter Gas Line to Diameter Heater to System to Fixtures Lt. Heater of Flue Gals. Inches Inches Inches Inches 30 % M 10 M. 3 50 1 1 10 H 4 100 1 to l}4 1 tol}^ 10 1 4 200 1 tolj^ 1 tol}^ 30 1 6 300 lJ^to2 lJ^to2 45 1^ 6 400 lHto2 lJ^to2 60 m 7 500 2 to 2^ 2 to 21^ 80 2 8 In Tables LXXIV to LXXX inclusive, will be found records of the actual performance of water heaters in sev- eral different types of buildings. The data were compiled by the American Gas Association, and the gas used had an approximate heat value of 650 B. T. U. per cubic foot. Digitized by Microsoft® 282 Principles and Practice of Plumbing oocc to 1 Sji O O i« CO *' l| t^ouJdi-i ■S v O O coco 1-1 MOCOP5 t-" 5^ WIS it 1— ( 1— ( j_^ CO «l CO 01-* s >. (4 >> l~ O t^ T-i 1-i .5 a ii5 i-i »rt i« 1-^ S,^ -HlOtOTO •OQ 05 r-t CO CO %a ti'^ CO CO i-H ■5 O •^^^ .— 1 1-H (M s 3 >. 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They are usually located near the kitchen range, and the water in them is heated by the waterback in the range. Some boilers are made of copper, some of wrought- iron and some of steel. Wrought iron and steel boilers are made plain, painted and galvanized. Range boilers of larger capacity than 200 gallons are not made in stock sizes. Copper Boilers. — Copper boilers are made for both low pressure and for heavy pressure water supplies. A low pressure boiler is made of light cold-drawn copper, polished on the outside and generally tinned on the inside. They are tested to about 75 pounds pressure, and are suitable only for systems where the pressure does not exceed 20 pounds per square inch. The chief objection to boilers of this type is their liability to collapse from atmospheric pressure when the water is in any way siphoned from them. Copper boil- ers, while they cost more, are better than iron boilers for storage purposes. They are cheaper in the end as they last longer, and rust will not accumulate in the boiler to discolor clothes in washing, as it does with black or galvanized iron boilers. Safety Copper Boilers. — Safety copper boilers are made with internal brass ribs to reinforce them. In some types of safety boilers, the internal rib runs spirally around the boiler from one end to the other. Reinforcing boilers makes them proof against collapsing from external pressure. Safety copper boilers are tested before shipping. There are two grades of safety boilers : one tested to 150 pounds pressure and guaranteed to stand a working pressure of 100 pounds ; the other tested to 250 pounds pressure and guar- anteed to stand a working pressure of 150 pounds. Both grades are guaranteed against collapsing, provided no check valve is used on the cold water supply to the boiler. If a check valve is used it confines to the boiler the water that Digitized by Microsoft® Principles and Practice of Plumbing 289 would otherwise expand back into the water mains, when the water in the boiler is heated, and expansion might sub- ject the boiler to a pressure far in excess of what it is guar- anteed to stand. Copper boilers are the best-appearing range boilers made. They are easily stained green, how- ever, and they radiate heat to surrounding objects at a greater rate than do iron boilers. Galvanized Eange Boilers. — These boilers are made for both standard and extra heavy pressures. The stand- ard boilers are generally marked tested to 150 pounds press- ure and rated to stand a working pressure of 85 pounds. The extra heavy boilers are marked tested to a pressure of 200 pounds and rated to stand a working pressure of 150 pounds. Galvanized range boilers are made both single and double riveted. Single rivet boilers have but one row of rivets along the seam, while double rivet boilers have a double row of rivets along the seam. Galvanized range boilers are galvanized after being made, and are galvanized both inside and out. The coating of zinc deposited on both inner and outer surfaces helps to make the joints and rivets water-tight. Galvanized range boilers are not all guaranteed, and notwithstanding the stenciled statement printed on each boiler that it has been tested to a certain pressure, they are seldom tested before leaving the factory, and are not suitable for pressure of more than one-half that which they are marked tested. Mud Drum for Boilers. — In localities where the water supply carries large quantities of clay or loam in suspension, a boiler with a mud drum or sediment chamber. Fig. 131, may be used. The boiler will then serve as a settling basin and most of the suspended matter will settle to the bottom of the boiler and into the sediment space. It can then be washed out at suitable intervals by opening the blow-off cock at the bottom of the boiler. If the particles held in sus- pension in the water are comparatively coarse, about fifty per cent, will be removed by sedimentation. Hot Water Tanks. — Hot water tanks are large wrought-iron or steel storage tanks of 200 gallons or more capacity, used in connection with water heaters. They are Digitized by Microsoft® 290 Principles and Practice of Plumbing generally used plain or painted, but are seldom galvanized. Large hot water tanks are seldom carried in stock, but are made to order. A sketch, showing the location and size of all outlets should accompany all orders for hot water tanks. The size of the tank and pressure of the water should always be considered when ordering, and when storage tanks are extremely large and subject to great internal pressure, stay bolts and cross braces should be used to give the tank addi- tional strength. Boilers and tanks, of whatever type or make, should be tested and guaranteed to stand a pressure of at least double the static pressure of the water to be stored. This is to provide a factor of safety for occasions when the internal pressure is increased by the ex- pansion of the water when heated, or the increased press- ure, perhaps double the static pressure, due to water hammer. Supports for Boilers and Tanks. — Range boilers are usually placed alongside the kitchen range in a vertical posi- tion, where they rest upon a cast iron boiler stand. When range boilers are placed horizontally they usually rest on iron brack- ets attached to the top or back of the range. Horizontal stor- age tanks are generally sup- ported by iron bands attached to the iron floor beams above. When they are set vertically they are supported by iron frames or legs. Large tanks should have cross braces within to give them strength to withstand racking stresses. Proportioning Size op Tank and Boilers. — Range boilers and heater tanks are used to store water heated by waterback or water heater during periods when hot water C Fig. 131 Sediment Cliombers for Boiler Digitized by Microsoft® Principles and Practice of Plumbing 291 is not being drawn. It thus provides a supply to draw upon when hot water is used faster than it can be heated by the waterback or heater. Also, it allows a smaller heater to be used than would be the case if water were drawn direct from a heater and had to be heated as fast as used. The size of a tank for storing hot water should bear a certain relation both to the capacity of the heater and to the number of gallons of hot water used daily. If the tank is too large for the heater there will never be a supply of hot water in the tank, and if the tank is too small the water will become heated to above 212 degrees, and when released from the faucet will flash instantly into steam ; also in many cases it will cause a rattling, snapping sound in the heater. An ordinary range has a waterback with a heating sur- face of about 110 square inches exposed to the fire. A waterback of such a size will ordinarily heat sufficient water for an average size family. It can be used in connection with any size boiler, from 35 to 50 gallons capacity. The size of the boiler should depend upon the probable amount of hot water that will be used daily. If the water is used uni- formly throughout the day, and almost as fast as it is heated, a 35-gallon boiler will be sufficiently large. If, on the other hand, the water is drawn intermittently, with long intervals between drafts, a larger boiler should be used to store the water heated during the intervals. In public and semi-public buildings, where large quan- tities of hot water are used, the heater must be large enough to heat water as fast as it will probably be used during periods of average consumption, and the hot water tank should be large enough to store sufficient water for one hour's maximum supply. For instance, in an apartment house where the probable maximum consumption of hot water would equal 250 gallons per hour, and the average consumption 125 gallons per hour, the heater should be capable of heating at least 125 gallons per hour, from ordi- nary temperature to 180 degrees, and in hotels and laun- dries the tank should have a storage capacity of 250 gallons. Water is seldom used hotter than 130 degrees Fahren- heit, so that water of higher temperature mixed with cold Digitized by Microsoft® 292 Principles and Practice of Plumbing water increases the volume of available hot water. In Table LXXXI can be found the temperature at which hot water is used in buildings of different classes. The size of hot water tank required for a large building depends so much upon conditions peculiar to that building that a satisfactory rule applicable to all cases cannot be formulated. A safe rule is to allow a sufficient capacity in the tank for the maximum hourly consumption. An ap- proximation that will be found sufficient for most apartment houses is to allow from 5 to 7 gallons capacity in the tank for each inmate the building will accommodate. For large hotels and public institutions that have accommodations for 300 and more people, a smaller allowance, about from 2 to TABLE LXXXI. Water Temperatures Required for Various Classes of Service Service Garages (for washing cars) General domestic use Laundry (hand work) Laundry (machine work) Birber shop (not sterilizing) Bars and soda fountains (hot drinks) Lavatory and cleaning uses Baths only Shower baths Swimming pools Baptistries Dishwashing (hand work) Dishwashing (machine) Milk dealerfe (not sterilixing or pasteurizing) Temperature required Minimum Maximum 80 100 130 160 115 212 180 212 115 150 175 212 115 150 110 150 110 150 80 212 80 212 130 212 180 212 115 150 4 gallons per capita, will be found sufficient. Take the case of a twelve-family apartment house in which sleeping accommodations are provided in each apartment for four people, and in the janitor's apartment for two. That would make accommodations in the building for 50 people. Allow- ing 7 gallons capacity in the hot-water tank for each inmate of the building, it would require a 350-gallon storage tank and a heater with a capacity of 175 gallons per hgur, That Digitized by Microsoft® Principles and Practice of Plumbing 293 will allow each tenant of the building to take a hot bath within an hour, and have a sufficient supply for the purpose. It will take each person fifteen minutes to take a bath. At the beginning of the hour, there is in the tank 350 gallons of water at a temperature of about 200 degrees, and the heater is supplying water at that temperature at the rate of 175 gallons per hour, making a total of about 525 gallons of water at a temperature of 200 degrees available within 60 minutes. That will allow for each bather, lOi/^ gallons of hot water of that temperature. A bath at any temperature between 98 and 104 degrees Fahrenheit is considered a hot bath, so if we allow for the water to be used at a tempera- ture of 110 the allowance will be safe. Assuming that the water in the street main is at a temperature of 65 degrees, then, mixing IOI4 gallons of water at 200 degrees with 21 gallons of water at a temperature of 65 degrees, would give a resultant temperature to the entire mixture of 110 degrees Fahrenheit, the temperature required for bathing. Now, 30 gallons of water is sufficient for a bath, either shower or stationary; and, as it will be very seldom that all tenants will bathe within the same hour, there will invariably be a reserve supply always on hand. At the same allowance, this would give each family 120 gallons of water the first hour at a temperature of 110 degrees for washing, and about 15 gallons at a temperature of 200 degrees for wash- ing clothes ; and this allowance will be found to be sufficient for all purposes. Each class of building must be considered separately. In an apartment house the maximum consumption of hot water would be at the hour of arising. At this time break- fast is in progress and there is so little dish washing or clothes washing being done that it is negligible. It is not likely that more than four baths can be taken in an hour in any one bath tub. As a matter of fact, the average would probably be below two, but maximums are what must be provided for. The temperature of water in which people like to bathe varies with the individual. Baths in water from 65 to 80 degrees Fahrenheit are considered cold ; in water from 80 to Digitized by Microsoft® 294 Principles and . Practice of Plumbing 92 degrees Fahrenheit, tepid ; from 92 to 98 degrees Fahrert^ heit, warm; and from 98 to 104 degrees Fahrenheit, hot; Again the maximum must be taken, for when a person likes a hot bath he likes it hot. The problem is, then, to find the amount of hot water that will be required per hour for each bath tub. Having that, it can be multiplied by any number of baths. An ordinary five-foot tub when filled 5l^ inches deep, contains fifteen gallons of water. That is the depth of water per- haps most generally used. At a depth of 61^ inches, an uncomfortable depth, the tub contains twenty gallons of water. For a hot bath at a temperature of 100 degrees, water from the heater delivered at 180 degrees, and the cold water flowing at 60 degrees, would require 7 gallons of hot water and 13 gallons of cold water. That would be equal to 28 gallons of hot water per family in an apartment house, and in a twelve-family apartment would require a . hot water tank with a capacity of 12 X 28 equals 336 gallons, and a heater with a capacity of half that amount per hour. It will be observed that there is a liberal factor of safety in the foregoing proportion. In the first place, there would not be four baths per family in any one hour in every apartment. In the second place, if there should be, they would not all be hot baths at a temperature of 100 degrees ; and, finally, should 28 baths of 20 gallons each be taken in any one hour, at a temperature of 100 degrees, by the end of that hour the original hot water would all be drawn from the tank, but the heater would have replaced half that amount, so more than seventy-five per cent, in excess of the number of baths actually provided for could be taken. In the chapter on heating water by gas will be found the actual amount of hot water supplied per day, per maxi- mum hour and per week in buildings of various types. In Table LXXXII will be found useful data to aid in estimating the quantity of hot water required per hour in various types of buildings. Boiler and Tank Connections. — Connections be- tween tank and heater should be made with copper, brass or Digitized by Microsoft® Principles and Practice of Plumbing 295 iron pipe. Lead pipe is unsuitable for hot water connec- tions, as it expands when heated and upon cooling does not contract to its original length, but sags when run horizon- tally, thus forming traps in the pipe. Furthermore, the TABLE LXXXII. Estimating the Hot Water Required for Various Types of Buildings FIGURED AT PINAIi TEMPERATURE OF 150 DEGREES GALLONS OF WATER PER HOUR PER FIXTURE V a 1 1 1 m 3 1-1 '3 M n i 1 cJ > Basin Private Lavatory Basin PubUc Lavatory Bath Tub Dish Washer Foot Basin 3 5 15 15 3 10 25 75 10 80 20 3 5 15 30 3 20 35 75 20 150 20 3 5 30 "i2 150 3 8 30 30 3 20 35 100 to 180 20 80 20 3 15 30 30 "20 '200 20 3 8 30 30 3 20 35 100 to 180 20 100 30 3 5 3 5 3 8 30 3 "15 15 3 10 "is 3 10 30 30 Kitchen Sink Laundry Station- ary Tub 42 100 to 180 10 10 25 75 10 80 15 10 ■'20 200 20 20 35 Laundry Revolv- ing Tub (each). Pantry Sink Shower 15 100 to 180 260 15 100 to 180 20 ^00 Slop Sink 20 Dish Washer 220 gal. per hr. at 180 for serving capacity of 500 people Recommended heating capacity in gals, per hour in P. C. of total water for all fix- tures Recommended storage capacity in gals, in P. C. of total water for all fixtures 35% 35% 60% 40% 80% 40% 45% 45% 90% 50% 75% 45% 100% 50% 20% 40% 100% 50% 50% 30% 25% 40% 75% 50% joints on lead pipe are liable to be melted and pull apart when the temperature of the pipe becomes very high, or should the water be siphoned out of the boiler below the Digitized by Microsoft® 296 Principles and Practice of Plumbing waterback, the heat from the fire would melt off the solder'ed joints. Circulation between water heater and tank is impeded by friction, therefore the ends of brass, copper and iron pipe should be carefully reamed to re- move the burr formed by cutting, and 45 degree bends or large radius 90 degree bends of recess pattern should be used to connect the heater and tank. Pipe of smaller diameter than %-inch should never be used to connect a waterback or heater to a storage tank, and the larger the pipe used within reasonable limits the better the circulation of water. The usual method of connect- ing a heater to a hot water tank is shown in Fig. 132. The circula- tion pipe, a, from the bottom of the tank is connected to the bottom opening of the waterback, and the flow pipe, b, grades from the top opening of the waterback up to the side connected to the boiler, about one-third distance from the bottom. The coldest water in a tank is always at the bottom and the hottest water at the top ready to be drawn through the hot water pipe. The temperature of the water grades uni- formly from the hottest water at the top to the coldest water at the bottom of the tank. The flow pipe, b, must always have a rise from the waterback to the boiler. If it should be trapped, the water will not heat, and a rattling, snapping §ound will be heard wh§n a fire is started, Digitized by Microsoft® Pnnciples and Practice of Plumbing 12&'? A better way to connect the flow pipe from a waterback to a range boiler is shown by the dotted lines, c. In place of entering the side of the boiler, as in the ordinary method, the flow pipe is connected to a branch in the hot water sup- ply above the boiler. The efficiency of a heater depends upon the velocity of the circulating water, and the velocity depends upon the vertical height of the column of water, therefore with the flow pipe connected to the top of the boiler there would be a greater head, consequently a greater velocity than if the flow pipe entered the side of the boiler. Some plumbers object to the top connection on account of the possible loss of circulation in case the water is siphoned from the boiler to the level of the hole, /, in the cold water tube, or to the bottom of the cold water tube, d. The objection is not a good one, however, for as long as the waterback remains full of water no damage can result. If steam is generated it will either condense on the walls of the boiler or escape through the cold water pipe to the street mains. It is only when water is siphoned out of a boiler low enough to empty the waterback that it is dam- aged. Then, if the fire is continued in the range, the water- back becomes overheated, and is liable to crack if cold water is quickly turned into it. The top connection might be objectionable when a cir- culation pipe is carried back from the fixtures. In such a case the hot water from the waterback would circulate through the hot water supply pipe, not through the boiler. The cold water supply to a boiler usually enters the top and is conducted down through the hot water by a tube, d. If the tube were omitted cold water might short circuit from the cold water to the hot water pipe, as shown by the arrow, h, and cold water would then be drawn from the hot water faucet. If the cold water supply did not short circuit to the hot water pipe, it would mingle with the hot water at the top of the boiler, thus tending to cool it. The tube, d, should be tapped at / with a hole sufficiently large to admit air to break the siphon in case a vacuum is formed in the cold water supply pipe. The size of the hole should vary 'Digitized by Microsoft® 298 Principles and Practice of Plumbing with the size of the tube, and should have a sectional area of at least one-quarter the sectional area of the tube. The cold water tube in a boiler should never extend below the level of where the flow pipe enters the side of the boiler. If water is siphoned from the boiler it cannot be emptied below the end of the cold water tube, and if the end of the tube is above the flow pipe from the waterback, it provides for circulation through the waterback when the flow pipe is connected to the side tapping in the boiler, and in any event it will ensure the waterback remaining full of water when the siphonage takes place. Boiler tubes for the cold water should be of brass or copper to prevent their rusting off or the vent tube choking with rust. Many plumbers now connect the flow pipe from the waterback to both the side and to the top of a boiler, as shown by the solid lines, b, and dotted lines, c, in the illus- tration. Safety Appliances. — The most serious result of water being siphoned from a boiler is the liability of the boiler collapsing from atmospheric pressure. To prevent this, a vacuum valve can be placed close to the boiler in a branch to the cold water pipe. The vacuum valve will admit air to the boiler in case a vacuum is formed, and thus prevent the boiler being emptied and then collapsed by external press- ure. A vacuum valve should be used whenever a boiler is located at such a height in a building that there is danger of the water being siphoned out when a cold water faucet is opened at a fixture below, after the water is shut off from the building. Another way of preventing the water being siphoned from a boiler is to place a check valve in the cold water pipe. This method, however, prevents the water expanding back into the street mains when the water is heated, and might cause the boiler to burst from internal pressure unless some relief is provided. Relief is generally provided under such conditions by means of a safety valve or expansion pipe. A safety valve, Fig. 133, consists of a valve that is held closed by means of a spring adjusted so that when the internal pressure reaches a certain intensity it will open Digitized by Microsoft® Principles and Practice of Plumbing 299 the valve and hold it open until the pressure is reduced, so the spring can close the valve again. A safety valve should always be used in connection with a check valve when the water is supplied from a street main. The outlet to the safety valve should be connected to a pipe leading to a sink, so that in case it blows off, the water will not be scattered over the kitchen, and scald anyone. Combined safety and vacuum valves are sometimes used to provide safety against rupture from internal press- ure or collapsing from atmospheric pressure. An expansion pipe is used only with tank pressure. It consists of an extension of the hot water pipe up to and over the cold water supply tank, where it should return so as to discharge steam or water into the cold water tank. An expansion pipe also serves as a temper- ature regulator. A blow-off cock should be provided with every boiler to draw off water from it when necessary to empty the boiler. In practice it is quite usual to connect the blow-off pipe direct to the drainage system, either to the kitchen sink trap or to the waste pipe below the sink trap. This is bad practice. When a building is closed for any great period of time, the boiler is usually drained of water and the ^. ,„„ •' I'lg. 133 blow-off cock left open to carry off any safety vaiTc drip from the pipes or boiler. That, provides a direct com- munication between the house drainage system and the water supply system and possibly the living rooms. The best place to discharge the water from the blow- off of a boiler is in a trapped and water-supplied sink when there is one at a lower level than the boiler blow-off. When there is not, a compression hose bibb connected to a branch of the circulation pipe to the waterback will provide a means of emptying the boiler through a hose or into pails. The blow-off cock should always be located at the lowest part of the water heating apparatus, so it can be completely Digitized by Microsoft® 300 Principles and Practice of Plumbing drained of water. If the waterback is located on one floor and the boiler at a higher level, then the blow-off cock would have to be connected near the waterback. Double Heater Connections to Boilers. — Two or more heaters are sometimes connected to one boiler. For instance, a coal or gas heater is sometimes used to heat the water during summer months, and a steam coil used to heat the water during winter weather. Each connection would be made independently of the other under such cir- cumstances, and either means or both means could be used together to heat the water. The real test of the effi- ciency of a double heater con- nection to a boiler is the ability to heat with one or both heat- ers together. When two water- backs or heaters are connected to the one hot water tank, by joining the flow and return pipe from both circuits, great care must be taken to connect them in such a manner that the current from one circuit will not be stronger than the cur- rent to the other circuit, and thus short circuit the strong current and shut off the flow from the weak one. That is what usually happens when one heater is located at a lower level than the other heater, or if located at the same level but at a great distance. Also, it might happen if one circuit was made of smaller pipe than the other one, or for any other cause was subject to greater friction. The best way to connect Wq pr more heaters to one Fig. 134 Two Heater Connections to Boiler Digitized by Microsoft® Principles and Practice of Plumbing 301 ^ -^ tank is to connect each one separately. If there are only two heaters they may be connected as shown in Fig. 134, or the flow connection can be reversed, so the flow pipe from the heater on the lower floor will enter the top of the boiler. This will not affect the circulation from either heater otherwise than to cause a loss of velocity in the upper circuit, due to loss of head. If more than two heaters are to be connected, special tappings should be provided in the tank for the extra flow and circula- tion pipes. When two heaters ai-e located at different levels they are sometimes connected so the water will pass in circuit through both of the water- backs. This, however, is a poor method of connecting them. When a fire is burning" in only one heater, a great amount of heat is lost by radia- tion in passing through the cold heater and extra circulation piping, and when there is a fire in both heat- ers the heat imparted to the water in the tank is less than if each heater was connected separately to the tank. Heater Connection to Boiler AT Lower Level. — Circulation can be secured and the water heated in a boiler that is located below the level of the waterback, as shown in Fig. 135. When the boiler is so located, however, the circulation is sluggish j-ig. 135 at all times, and the weights of the Heater connected to Boiler , 1 J? J. Ill at Lower Level two columns of water so nearly bal- ance each other that good circulation cannot always be de- pended upon. Better results will be obtained by suspend- ing the boiler in a horizontal position close to the cellar Digitized by Microsoft® ^02 Principles and Practice of Piumhing ceiling, and extending the top loop at least twice the height of the lower loop or portion of the circuit. Also make the top or horizontal portion of the upper loop two sizes larger than the flow and return pipes, and as long as possible. In connecting the waterback to the boiler under such condi- tions, the circulation pipe from the boiler to the waterback is taken from the bottom of the boiler, and the flow pipe from the waterback to the boiler is extended vertically from the waterback to a distance equal to the distance from the waterback to the bottom of the boiler. If greater vertical height can be given to flow pipe, the more positive will be the circulation. The circulation pipe returns from the high- est point to which it is carried and enters the top of the boiler. The hot water pipe is taken from the top of the circulation loop or a separate connection from boiler. Connections to Horizontal Boilers. — Boilers are sometimes placed in horizontal position when there is no floor space to set them vertically. The usual tapping for a vertical boiler may be used when set horizontally, but the better practice is to have special tappings. When a vertical boiler is placed horizontally and stock tappings used, a boiler tube should be placed in the hot water pipe and curved upward inside of the boiler so as to offer an outlet near the top of the boiler for the hot water. The side tapping of the boiler is turned down and used for the cir- culation opening to the waterback. The flow pipe from the waterback enters what would be the bottom tapping of the boiler and the cold water enters the cold water tapping without a tube. The only special tapping necessary for a horizontally placed boiler is on the top side, to provide a connection for the hot water pipe. Overheated Water. — As previously stated, the rela- tion between the boiling point of water (which also is the generating point of steam) and pressure is absolute. Un- der a given pressure water will boil and steam will generate at a certain temperature. Increase the pressure and the point at which the water will boil will also increase. Thus, at atmospheric pressure, water will boil at 212 degrees Fahrenheit, while if the pressure is increased to 50 pounds, Digitized by Microsoft® Princivles and Practice of Plumbing 303 a common pressure for water in city mains, the boiling point of the water will be increased to 297 degrees Fahren- heit. If water under pressure is raised to a temperature above 212 degrees Fahrenheit and then released to the atmosphere, part of the water will instantly flash into Co/cf steam and continue to generate steam until the temperature of the water is re- duced below the boil- ing point at atmos- p h e r i c pressure. Thus, when water under pressure in a tank is raised to the boiling point at that pressure and a hot water faucet is open- ed, steam will flow from the faucet with a sputtering sound caused by the mix- ture of water with the steam. This flow of steam will con- tinue until the tem- perature of the water in the tank has been lowered by the in- flowing cold water to below 212 degrees Fahrenheit. The hot water tank is not full of steam, as would appear to the person at the faucet, but the water is instantly converted into steam as soon as the pressure is released from the water at the faucet. The overheating of water in a tank can be prevented by the use of temperature regulators, which are made to control the supply of steam to steam coil, also to regulate the drafts to water heaters, Fig. 136 Draft Regulator Digitized by Microsoft® 304 Principles and Practice of Plumbing and by these means maintain a uniform temperature of water in a tank. Draft Regulators. — An apparatus used to regulate the drafts of a water heater is shown in Fig. 136. It con- sists of a chamber, a, enclosed in a casting, b, with an an- nular space between them for water to circulate through. The inner chamber is connected by means of a pipe, c, to a diaphragm in valve, d, which it fitted with a lever and chain, so that any movement of the lever will open or close the dampers. The regulator is attached to the flow pipe from a heater, as shown in the illustration. The operation of the apparatus is as follows : The inner chamber is partly filled with water through the plugged connection, e, and the plug screwed in to prevent the escape of water or steam. The water in the inner chamber is under atmospheric press- ure, which boils at 212 degrees Fahrenheit, while the water in the heater is under an additional pressure that prevents it boiling at the same temperature as that in the chamber ; hence, when the temperature of the water in the heater rises above 212 degrees Fahrenheit it will cause the water in the chamber to generate steam, which presses the water against the diaphragm of the valve, d, thereby depressing the lever and closing the dampers. The fire is at once checked and no steam can form in the hot water tank, as the boiling point for the corresponding pressure has not been reached. When the temperature of the water in the heater falls below 212 degrees Fahrenheit the steam in the chamber condenses and pressure is released from the dia- phragm, which immediately settles back into place, thus opening the dampers. Steam Coil Regulators.— A regulator used for con- trolling the supply of steam to heating coils in tanks is shown in Fig. 187. It is operated by means of the unequal expansion of two different metal bars, a, which when heated to a certain temperature by water in the tank, b, open a small valve, c, in a water supply pipe, thus admitting the water pressure to the diaphragm valve, d. The pressure of water on the diaphragm closes the valve and thus cuts off the supply of steanj froin th§ coiL As sooij a§ the temper^. Digitized by Microsoft® Principles and Practice of Plumbing 305 ture of water in the tank falls sufficiently, the metal bars contract, thus shutting off the supply of water from the diaphragm valve, which is opened by a spring and again admits steam to the coil. Circulation Pipes. — Hot water pipes that are extend- ed any great distance to a fixture or group of fixtures should be provided with a circulation pipe through which hot water can circulate and thus be close to the faucets at all times. If circulation pipes are not provided, the water in hot water pipes cools when not being constantly drawn, and much time is wasted emptying the pipes of cold water when hot water is wanted. The water annually wasted in this man- ner, in any building would more than pay for circulation pipes. When installing the hot water system, a return pipe of smaller diameter than the hot water pipe is carried from the highest point of the hot water riser back to the boiler, where it may be connected to a separate tapping in the boiler or it may be connected to the return pipe from boiler to waterback. A valve should be put in each return pipe in a position to correspond with the shut-off valve in a hot water pipe, and both should be opened or closed as the case may be. Should only the hot water valve be closed, water would back up through the circulation pipe, and should the return valve be closed there would be no circulation through the pipes. A hot-water pipe should rise from the boiler connection to the highest point in the system, then return to the bottom connection of the boiler or to where it is connected to the apparatus. If the hot-water pipe should dip below its grade, should be trapped, or pitch down instead of up, the sygtem wQuld not work, and there would be no circulation. Fig. 137 Steam Coil Regulator Digitized by Microsoft® 306 Principles and Practice of Plumbing The return pipe from the highest part of the circulation system may be trapped or dip below the level of the boiler, as, for instance, should it be necessary to carry the return to the boiler in the basement or cellar, and this will not interfere with the circulation of water. The hot-water pipe, however, must have a positive rise from the boiler to the highest point in the system. Gravity circulation cannot be maintained in long, low buildings without the aid of a circulating pump. If the length of the building is not too great, circulation can be maintained by rising direct from the boiler to the top of the building, along the ceiling of the top floor to the end of the run, down to supply the groups of fixtures, and back to the boiler along the cellar ceiling. Expansion of Pipes. — Water pipes expand or contract for every change of temperature to which they are sub- po. jected. To provide / ,^ I for this, in all tall ,_[" ff O >] buildings expansion v| ] ^ „ I loops are placed in r, ■ — --— 2^ — '= JJ— ^ both hot water and /-4c: circulation pipe to J. permit the expan- Flg. 13S . J J. J Expansion Loop sion and Contrac- tion of the lines without injury to the pipes. The loops are usually from 6 to 8 feet long', made as shown in Fig. 138, placed under floors and spaced about 50 feet apart. Usually hot water and circulation pipes are fastened midway between loops and allowed to expand both up and down. Long horizontal runs should likewise have expansion loops or room to ex- pand. The length that water pipes will expand depends upon the degree to which they are heated and the material of the pipes. Within ordinary ranges of temperature, cast iron pipe varies f^-^y^^ of its length for each degree Fahren- heit, heated or cooled. Wrought iron pipe varies jy^Voo of its length for each degree Fahrenheit heated or cooled, and brass pipe varies ^. - ^ ^^ ^^ of its length for each degree Fahrenheit heated or cooled. Hence the expansion or con- Digitized by Microsoft® Principles and Practice of Plumbing 307 traction of any pipe, when the length and the temperature of water are known, can be found by the following rule : Rule — Multiply the length of pipe in inches by the num- ber of degrees Fahrenheit it is heated or cooled, and divide the product by the coefficient of expansion for the kind of pipe used. •Expressed as a formula: e ^ — . When 1 ;= length of pipe in inches, h = degrees Fahr. the pipe is c 1 . • 1 cast iron, — ■ 162000 150000 heated or cooled, c ^ coefficient of expansion ( 1 wrought iron and /. brass) , e = elongation of pipe in inches. Example — What will be the expansion of a wrought iron pipe 100 feet long when heated from 60 to 212 degrees temperature? Solution— 100 ft. X 12 in. X 152 = 182400 -^ 150000 = 1.21 inches. In Tables LXXXIII, LXXXIV and LXXXV the linear expansion of cast iron, wrought iron and brass pipe for each 100 feet length at different temperatures is given. TABLE LXXXIII. Expansion of Cast Iron Pipe Tempera- length of Pipe when Fitted Length of Pipe when heated to ture of Air when Pipe is Fitted 21S Deg. Fahr. AtmoBpheric Pressure 265 Deg. Fahr. IS Pounds Pressure 297 Deg. Fahr. 84 Pounds Pressure 338 Deg. Fahr. 100 Pounds Pressure Deg. Fahr. 32 64 Feet 100 100 100 Feet Inches 100 1.59 100 1.36 100 1.12 Feet Inches 100 1.96 100 1.65 100 1.43 Feet Inches 100 2.20 100 1.96 100 1.73 Feet Inches 100 2.50 100 2.27 100 2.00 TABLE LXXXIV. Expansion of Wrought Pipe Length of Pipe when Fitted Length of Pipe when heated to ture of Air when Pipe is Fitted 2 IS Deg. Fahr. Atmospheric Pressure 26S Deg. Fahr. 15 Pounds Pressure 297 Deg. Fahr. 84 Pounds Pressure 338 Deg. Fahr. 100 Pounds Pressure Deg. Fahr. 32 64 Feet 100 100 100 Feet Inches 100 1.72 100 1.47 100 1.21 Feet Inches 100 2.21 100 1.78 110 1.68 Feet Inches 100 2.31 100 2.12 100 1.87 Feet Inches 100 2.70 100 2.45 100 2.19 Digitized by Microsoft® 308 Principles and Practice of Plumbing Pipe Coverings. — Hot water pipes and hot water tanks that are uncovered lose by radiation from their surface about 13 B. T. U. per minute per square foot of surface. TABLE LXXXV. Expansion of Brass Pipe Length of Pipe when Fitted Length of Pipe when heated to ture of Air when Pipe is Fitted 215 Deg. Fahr. Atmospheric Pressure 265 Deg. Fahr. 15 Pounds Pressure 297 Deg. Fahr. 84 Pounds Pressure 338 Deg. Fahr. 100 Pounds Pressure Deg. Fahr. 32 64 Feet 100 100 100 Feet Inches 100 2.58 100 2.19 100 1.81 Feet Inches 100 3.18 100 2.79 100 2.41 Feet Inches 100 3.56 100 3.18 100 2.79 Feet Inches 100 4.05 100 3.67 100 3.28 To prevent this loss of heat and consequent extra consump- tion of coal, hot water pipes, circulation pipes, and hot water tanks in large installations are usually covered with some non-heat conducting substance. TABLE LXXXVI. Values of Pipe Coverings Name Maker £ w 3 ■ at . " .2 a MttH »-l "* o S u ** a M . S C L^ oij B •S'SS Nonpareil Cork Standard Nonpareil Cork Octagonal Manville High Pressure. . Magnesia Imperial Asbestos "W.B." Asbestos Air Cell Manville Infusorial Earth Manville Low Pressure. . . Manville Magnesia Asbestos Magnabestos Moulded Sectional Asbestos Fire Board Caloite Bare Pipe Nonpareil Cork Co Nonpareil Cork Co Manville Covering Co. . Keasby & Mattison Co.. H. F. Watson H. F. Watson Asbestos Paper Co ManviUe Covering Co.. . Manville Covering Co.. . Manville Covering Co.. . Keasby & Mattison Co.. H. F. Watson Asbestos Paper Co Philip Carey Co 2.20 2.38 2.88 2.91 3.00 3.33 3.61 13.84 15.9 17.2 17.2 17.7 18.0 18.9 20.0 20.2 20.7 20.8 21.0 21.7 24.1 26.1 100.0 1.00 .80 1.25 1.12 1.12 1.12 1.12 1.50 1.25 1.50 1.12 1.12 1.12 1.12 27 16 54 35 45 69 35 65 48 41 35 66 Digitized by Microsoft® Principles and Practice of Plumbing 309 The relative values of different makes of pipe cover- ings, as determined by tests conducted by Charles L. Nor- ton, of the Massachusetts Institute of Technology, for the Mutual Boiler Insurance Co., of Boston, can be found in Table LXXXVI. Carbonate of magnesia is a very poor conductor of heat, therefore, it is a good material for covering hot water pipes. The name "Magnesia," however, is often applied to pipe coverings made of carbonate of lime, or of plaster of paris. Table LXXXVII shows the percentage of lime and magnesia found by C. L. Norton in several well-known brands of "Magnesia" coverings. TABLE LXXXVII. Lime and Magnesia in Pipe Coverings Percentage Composition Name Mg. CO, Carbonate of Magnesia Ca. SOi Sulphate of Calcium K. & M. Magnesia 80 to 90 Less than 5 20 to 25 Less than 5 10 to 15 3 65 to 75 Watson Moulded 50 to 60 75 Manville Ma""nesia Asbestos None Data on pipe covering from Circular No. 6 of the Mutual Boiler Insurance Company, of Boston. Mineral wool, which was always considered a good covering, was not reported upon by the above experimenter, for the reason that mineral wool is of no value as a heat retardant. "Under vibration it is apt to become more and more massed into a semi-solid, leaving the top of a pipe partially covered, the under side of the covering more and more solid and therefore less effective. It is a dangerous material to handle and to use. The fine dust getting under the nails creates irritation and sometimes bad sores, or, passing into the bronchial tubes and the lungs, sometimes causes hemor- rhage." The conclusions to which we have been led by the tests pn which report i§ now m^ide, are as follows ; Digitized by Microsoft® 310 Principles and Practice of Plumbing There are a sufficient number of safe, suitable and incombustible coverings for steam pipes and boilers to main- tain a reasonable and adequate competition, without giving regard to any of the composite pipe covei"ings which contain combustible material in greater or less quantity, according to the integrity of the makers, and without giving regard to pipe coverings which contain substances like the sulphate of lime, which may cause the dangerous corrosion of the metal against which it is placed. We therefore name as the pipe and boiler coverings which may have the preference in respect to safety from fire and efficiency in service, the following makes : Name Made by Nonpareil Cork Nonpareil Cork Co., Bridgeport, Conn. Magnesia Keasby & Mattison Co., Ambler, Pa. Asbestos Air Cell Asbestos Paper Co., Boston. Imperial Asbestos H. F. Watson Co., Erie, Pa Hair felt and wool felt when new are good heat retard- ants, but deteriorate with age, and besides furnish a breed- ing place for house bugs and vermin. The value of pipe coverings is not proportional to its thickness. Sectional pipe coverings average about 1% inches in thickness and reduce the loss by radiation about 90 per cent., doubling the thickness of pipe covering only saves about another 5 per cent, of heat loss. In specifying covering for pipes and boilers, there- fore, a thickness of 1% inches will be sufficient. Covering for PJastic Maanes/a s Covering Magnesia Block. Fig. 139 for Hot Water Tanl; Tanks. — On account of the objectionable appearance they would present, range boilers are seldom covered to prevent loss of heat by radiation. Hot water tanks, however, are usually located in the basement or cellar, where appearance Digitized by Microsoft® Principles and Practice of Plumbing Sll is of less importance than the prevention of loss of heat, therefore they should be covered with about 1% inches of some good non-heat conducting covering. Tanks are gen- erally covered with plastic asbestos troweled over a band of expanded metal, or asbestos blocks, Fig. 139, held in place by a wire netting. Digitized by Microsoft® Sl2 Principles and Practice of Plumbing CHAPTER XXIX ICE-WATER SUPPLY Cooling Tanks. — The cooling of water for drinking purposes begins at the cooling tanks, which must be rightly proportioned and properly built if the best and most eco- nomical results are to be obtained. Cooling tanks are noth- ing more or less than ordinary ice boxes, and any well-made ice chest can be used for the purpose, although on account of the hard usage received, it is well to have cooling tanks made of extra strength. Tightness and heat insulation are the two prime requi- sites of the ice box. The box may be made water-tight by lining it with sheet metal of some kind, or by placing inside of the ice chest a specially built galvanized steel tank. So far as efficiency is concerned, either will answer, although the steel tank will wear the better. The ice chest must be well insulated with from four to six inches of charcoal, granulated cork or some equally good non-heat conducting substance, and fitted with good covers, either single or double. Where only one drinking fountain is to be installed, or where the fountains are widely scattered, individual ice boxes for each fountain will prove the most satisfactory and economical. When, however, there are a number of drink- ing fountains grouped fairly close together, one ice box cen- trally located will be found the most satisfactory. An ice box suitable for this purpose is shown in Fig. 140. It will be noted that the ice in this box rests on a perforated platform above the ice coils. This prevents the coils from being damaged when putting ice in the chest, and, as the ice does not come in contact with the coils, neces- sitates retaining water in the tank. This is far from being a disadvantage, however, for the water from melted ice is cold enough to cool the drinking water to the right degree, and will absorb enough heat from the drinking water to make it economically advisable to use the water for cooling Digitized by Microsoft® Principles and Practice of Plumbing 313 purposes. For instance, the following data about water in an ice cooler of this description will prove the point: Temperature of water at surface in contact with ice 41° F. Temperature of water at bottom of ice box , 43° F. Temperature of water drawn at basement fountain 53° F. Temperature of water drawn at first floor fountain 53° F. Temperature of water drawn at second floor fountain 53° F. Temperature of water drawn at third floor fountain 53° F. Accepting the average temperature of the water in the ice chest as 42 degrees Fahrenheit, then it is only about ten degrees warmer than the temperature of the ice, and that ten degrees heat, or the greater portion of it no doubt, was absorbed from the drinking water passing through the coils. The waste and overflow connections are so arranged that water can be retained in the ice box up to the level of the overflow, and the water then overflowing is from the bottom of the ice box, where the warmest water will be found, or, by opening the valve in the waste pipe, the water will drain ou t as fast as the ice melts. In p r o- portioningthe ice box, about three cubic feet of space should be al- lo w ed for each drinking fountain to be served. Indeed, it would be well to allow slightly more space to take care of the ice needed in extremely hot weather, then the cooling of water can be regulated in ordi- nary weather by not using so much ice. The amount of ice j-equired will of course depend upon the weather- Qrdina,v- •Su/lfi/jTj Fig. 140 Cooliug Tank for Ice Water Supply Digitized by Microsoft® 314 Principles and Practice of Plumbing ily, 50 pounds of ice per day for each fountain will be found sufficient, although in excessively hot weather it might require over three times that amount. Cooling Coils. — In the foregoing illustration, the pipe coil is shown occupying the main part of the tank. This is not necessary, however, and other methods are often resorted to. For instance, a flat coil may be laid on the bottom of the ice tank, or wall coils, may be run around the sides of the tank thereby keeping them out of the way of the ice, so they will not be damaged when putting the ice in the box, and at the same time permitting a smaller size of tank to be used. When a bottom coil is used, it is well to fasten over the coil a rack or grating of heavy timbers, say 21/2 x 5, to keep the ice from coming in contact with the coils and possibly damaging them. Size and Material of Cooling Coils. — For ordinary service, 10 feet of %-inch pipe will be a sufficient allowance for each drinking fountain supplied. That would be the equivalent of about 2l^ square feet of surface, the inside surface of the pipe being taken, as that is the surface to which heat is applied ; fourteen feet of V2-inch pipe ; eight feet of Irinch pipe ; 61/4 lineal feet of ll^-inch pipe, or 51/^ feet of li/^-inch pipe. Water stands in the cooling coils sometimes for a long while, so it is undesirable to use lead pipe or common iron pipe for this purpose. Brass pipe, copper pipe, block-tin pipe or Benedict Nickel Steel pipe will be found best for this purpose. Distribution of Ice-Water. — Cold water cannot be satisfactorily circulated without the aid of a pump. The attempt has been made to secure a circulation by gravity, by locating the ice box in the attic, and depending on the heat- ing of the water in the down supply upsetting the balance of the two columns of water enough to cause an up circula- tion in the return pipe. The difference in temperature is so slight, however, and the friction of the pipe proportionally so great, that it will not circulate. Even if it did, there are practical objections to such a system of ice-ws^ter supply. Digitized by Microsoft® Principles and Practice of Plumbing ^1§ In the first place, there is the muss and fuss of carrying the ice to the attic, and in the second place, the attic being the hottest part of the building, and so much hotter than the cellar where it would naturally be located, that much more ice would have to be used to keep the water at the required temperature. Water Cooler for Out-Door Fountain. — For fac- tories spread over large areas, parks, public playgrounds and like places, a sanitary drinking fountain supplied with cooled water can be fitted up as shown in Fig. 141. Expe r i e n c e has shown that a brick r concrete vault 2 feet wide, 214 feet long and 31/^ feet deep, containing a little over 17 cubic feet of space, and capable of holding from 700 to 800 pounds of ice, will keep the water cool for 24 hours and in sufficient quantity to supply 3000 people. About 9 square feet of coil surface, or 21 lineal feet of 114-inch pipe will be found sufficient for ordinary locations ; but, where the flow is almost continuous, 14 to 15 square feet of pipe surface will be needed to keep the water copied to the right temperature. Water-Cooling Refrigerating Machines. — Mechani- cal refrigeration is now generally used for cooling the drink- -.MaAi P/pe. Fig. 141 Water Cooler for Outdoor Fountain Digitized by Microsoft® 316 Principles and Practice of Plumbing ing water for large office buildings, hotels, clubs and like buildings. This requires a miniature plant of its own, or an expansion or brine coil from the general system, when refrigeration for other purposes is required in the building. El The complete refrigerating sysLem for a water-cooling plant is shown in Fig. 142. This was designed with a capacity of from twenty-five to thirty drinking fountains, and is operated by an electric motor. In supplying ice Digitized by Microsoft® Principles and Practice of Plumbing 317 water to a building a pump is necessary to keep up a circu- lation through the supply pipes, so that cold water will be on tap the moment a faucet is opened. If the water- were not kept in circulation, it would soon grow warm, and con- siderable water would have to be drawn before cold water could be obtained. From the circulating pump the risers are taken to the attic, or 10 or 12 feet above the level of the highest fixture, if there are none on the top floor, then returned and discharged into the cooling tank. In some cases a small tank called a "balancing taflk" is provided in the attic, and the water from the risers discharge into this, the overflow being carried back to the cooling tank in the cellar or basement. Supply branches to the drinking foun- tains are taken off the up-risers, so there will always be a supply available, and under a suitable head or pressure. It is very necessary to insulate thoroughly the ice-water pipes or they will condense the moisture in the atmosphere, thereby "sweating" and being a nuisance generally. In proportioning the system, an allowance of about 3 gallons capacity in the cold water tank for each fountain to be supplied, will be right for ordinary service. Actual Performance of Refrigerating Machine. — In the 30-story Union Central Office Building, Cincinnati, Ohio, a 10-ton Frick machine furnishes the tenants with ice water. Steam pressure 80 pounds; back-pressure on con- denser 15 pounds, and condenser pressure 150 pounds. City water is taken in at a temperature of 75 degrees Fahrenheit and cooled to an average of 44 degrees at the fountains throughout the building, of which there are 50 between the basement and the twenty-eighth floor. There were 468 pounds of steam used by the ice machine per hour, or 3,744 during the eight-hour test, which required 430 pounds of coal, Digitized by Microsoft® 318 Principles and Practice of Plumbing CHAPTER XXX WATER SUPPLY FOR SUBURBAN PLACES Windmills. — One of the cheapest and most satisfac- tory ways of pumping water for domestic or irrigation pur- poses is by means of windmills. There are two types of windmills in use, distinguished by the materials used in making the sails* of the wind wheel. One is the windmill with the sails of the windwheel made of narrow strips of wood set at a steep angle. Such windmills run at slow speed and operate the pump direct from the crank, and are called "direct-stroke" windmills. The other type has curved steel sails set at a flat angle in the windwheel. These wheels revolve at high speed, and the high speed of the windwheel is geared down to the proper speed for operating the pump. These windmills are known as "back-geared" windmills. Both types of windmills have certain features adapting them to different requirements. Action of Wind on Windmills. — It requires at least an 8-mile wind to do any effective work with a windmill, and they will not operate to the best advantage in winds of over 25 miles an hour. Very few windmills are made with larger wheels than 30 feet in diameter, and they are regu- lated to govern at a velocity of 25 miles an hour. There are no pumps or attachments which will enable the user of a windmill to utilize the increased power obtained from winds of high velocity, so that in practice the amount of water pumped by windmills in high winds is but little more than is pumped by the same mills in winds having velocities of from 12 to 18 miles an hour. The velocity of wind, pressure per square foot on the sails and action of the wind on a windmill, can be seen in Table LXXXVIIL From the table it will be seen that the only available winds are those blowing with a velocity of from 8 to 25 miles per hour, and that a 15-mile wind can be utilized to the best advantage. It is best, therefore, to "load" a wind- mill for a 15-mile wind. It will then start pumping in an Digitized by Microsoft® Principles and Practice of Plumbing 31& 8-mile wind, do excellent work in a 15-mile wind, and reach the maximum results in a 25-mile wind. It will be further observed that a wind velocity of 15 miles per hour develops a power three times as great as an 8-mile wind; and a 20-mile wind is twice as powerful as a 15-mile, or six times that of an 8-mile wind. It naturally follows that a small increase in velocity greatly increases the power of wind- mills, while a low velocity gives but a low working force. TABLE LXXXVIII. Action of Wind on Windmills Velocity of Wind in Miles per Hour Pressure per Square Foot in Pounds Description of Wind Action of Wind on Windmill 3 5 8 10 15 20 25 30 .045 .125 .33 .5 1.135 2. 3.125 4.5 8. 12.0 18. 32. 50. Just perceptible Pleasant wind Fresh breeze Average wind Good working wind. . Strong wind Very strong wind. . . Gale Windmill will not run Might start if lightly loaded Will start pump Pumps nicely if properly loaded Does excellent work Gives best service Maximum results secured Should be furled out of work 40 Storm. . . Well constructed mills and 50 W 80 Severe Storm Violent Storm Hurricane towers are safe if properly [erected Buildings, trees, etc., might be damaged Buildings, trees, etc., would bo 100 Tornado damaged Ruin The capacities of windmills based on the size of wheel, velocity of wind, and revolutions of wheel per minute, can be found in Table LXXXIX. This table gives also the amount of water that can be raised to different heights or elevations. Average Velocity of Wind. — Windmills would be of but little use if there was not enough wind blowing to oper- ate them. As a matter of fact, at some time during every twenty-four hours, there is enough wind blowing to operate a windmill and pump water. The average velocity of v;ind throughout the entire United States is very nearly 8 miles per hour, while for large areas, such as the great plains east of the Rocky Mountains, the average is about 11 miles Digitized by Microsoft® 320 Principles and Practice of Plumbing per hour. Again, in certain small areas situated in moun- tainous districts, the average velocity is as low as 5 miles per hour; therefore, in selecting and loading a windmill, the wind velocity prevailing in the particular locality where it will be used must be considered. In such localities the mills should be loaded to operate in 10-mile winds, instead of 15-mile wind recommended for general use. A mill loaded for a 10-mile wind can be depended upon to furnish a sufficient supply of water in those localities where the average wind velocity is low. TABLE LXXXIX. Capacity of Windmills .2 Si Gallons of Water Raised per -=a Minute to an Elevation of >>UI ■*-> p, •^ -t-i & OJ |a 1| 25 SO 75 100 ISO 200 lis ay_ >.« A'$- Feet Feet Fee t Feet Feet Feet W ^ / y ? z ^« -t / 7 H <> / 7- ' ■ ? V ' ; 7 ■^' y ,' ' ^ '^ •/ ...., -..- V'/.l ^ V / / •- 1' / ■' 7 t' * _ / / / "7" 7--" / -y 7 t.. • ■■■■;'■■ 900 800 700 600 BOO 400 300 250 200 150 100 90 80 70 (B la « Fig. 144 ^Jiowing Allowable Spacing for Hoop^ Digitized by Microsoft® 324 Principles and Practice of Plumbing diagram : How far apart should 1-inch hoops be placed, at 15 feet from the top, on a tank 20 feet diameter? 15 X 20 = 300. Follow up the right side of the dia- gram where marked "Product of diameter (feet) X depth (feet) " till you come to 300 ; then follow the horizontal line to the left till it intersects the diagonal line marked "1-inch Hoop ;" then follow downward to the bottom of the diagram, and it will be seen that the hoops under conditions above stated may be spaced S%, inches apart. a ■■5 M o o , M 'M M .-K 11 Hoops i"dia, ?1 o <1> hD n « > n la I m C3 o Iff H a. o 1:^ -H; 1 = n > a io IO .-4-.< "M o o i-l i.H O t^i o ~ X o o o o in CM ^ r\s^:\\^\ l4Hoops I'dia. BHoopsFdia. 4HoopsFdla. llHoopsi'dia. l2Hoopsi'dia. Fig. 145 Proper Spacing of Hoops In a similar way the spacing for any hoop for any size tank may be found. Extra hoops must be provided near the bottom to take the additional load due to the swelling of the bottom planks. For tanks up to 20 feet in diameter, one hoop of the siz§ Digitized by Microsoft® Principles and Practice of Plumbing 325 used next above it must be placed around the bottom oppo- site the croze. For tanks 20 feet or more in diameter two hoops must be used as above. The hoop or hoops at the croze are to be counted upon as taking the water pressure of half the space above. The spacing of hoops on tanks is shown graphically for several different sizes of tanks in Fig. 145. Dimensions for Tanks op Standard Sizes. — For con- venience Table XCI, giving dimensions for a few tanks of certain sizes, is added. f FABLE XCI. Dimensions of Wooden Tanks SIZE (Outside Dimensions) Thickness of Lumber after being Machined 1 t B.....g ■ c Approx. Net Capacity ^ HOOPS Average Diam. Ft.-In. Lengtli of Stave Ft. Staves In. Bot'm In. 1 A In. B In. c In. No. of Size In. 10,000 13-4 12 2K 2H sy2 'A 2H 11 % 15,000 14-6 14 2M 2M W2 'A 2A 14 M 20,000 15-6 16 2M 2M 3M % 2A {.? A 25,000 17-6 16 m 2M m % "2% [i A 30,000 18-0 18 m 2M Z'A % 2^ {A A 40,000 19-6 20 2H 2% 33^ % 2^ 3 10 ill A 1 50,000 22-0 20 2M 2K sy2 2^ {.2 A 1 The number and size of hoops are stated and the spac- ing for same are shown in Fig. 145. The proper size and spacing of hoops for tanks of other dimensions can readily be computed by use of the diagram. Tanks located outdoors must be covered with a double roof, an acceptable construction being shown in plan in Fig. 146, and in elevation in Fig. 147. It myst consist of a tight flat cover made of matched boards supported by joists, Digitized by Microsoft® g26 Principles and Practice of Plumbing and above this a conical roof. In the larger sizes the conical roof must be supported by rafters extending from the top of the tank to the peak of the roof. The conical roof must be covered with galvanized sheet iron or a good composition roofing which is not readily ignitible. Fig. 146 Plan of Tank Roof Expansion Joint. — When a tank is supported by a tower 30 feet or more in height, whether on the ground or on a building, an expansion joint of the approved type shown in Fig. 148 must be provided in the discharge pipe at Fig. 147 Double Cover for Tanl£ the tank connection. In those cases where a tank is located in a brick or reinforced concrete tower, a four-elbow swing joint may be used. Digitized by Microsoft® Principles and Practice of Plumbing 327 Overflow Pipe. — The overflow pipe must be 2 inches in diameter for tanks up to 30,000 gallons capacity and 3 inches in diameter for larger tanks. A short length of 2-inch pipe will discharge about 100 gallons per minute when the surface of the water is three inches above the centre of the pipe. The top of the overflow pipe must be placed 3 inches below the top of the staves of a wooden tank and 1 inch below the top of the cylindrical shell of a steel tank. The overflow pipe must extend through the bottom or side of tank. In the latter case it must project beyond the balcony. Frost-Pkooping for Pipes. — The discharge and hot water or steam pipes, and separate filling pipe when one is needed, for a tank on a tower on the ground or roof of a building, must be pro- tected from freezing by a frost-proof covering in addition to having the water in the discharge pipe heated. The frost-proof cov- ering should not be de- pended upon to prevent freezing of the pipes without some heat being added. Most tanks for fire pro- tective purposes have no draft from them except in case of fire, therefore the water in the discharge pipes has little or no circulation. For this reason, these pipes need more thor- ough protection than do pipes in similar positions which discharge from tanks in which there is nearly constant cir- culation, as for example in a village supply. Therefore the amount of protection to be provided for a certain pipe must be decided with due regard to the severity of exposure to 1 1 nil 'ii 1 i mg. 148 Expansion Joint for Wooden Tanks Digitized by Microsoft® 328 Principles and Practice of Plumbing cold winter winds, frequency of circulation in the pipe and amount of heat to be supplied. The standard frost-proof boxings are made of wood and are circular as shown in Fig. 149, or square in section as shown in Fig. 150. The boxings may be made more durable by using stock which has been antiseptically treated. A good tight joint must be made between boxing and bottom of tank. The lower end of boxing must be sup- ported by the sides of the pit, which must extend about a foot above ground. The woodwork must be well painted. Sheet lead or tarred paper should be placed between bot- tom of boxing and the pit to avoid absorption of moisture. The upper part of boxing must be con- structed so as to permit of access to the expansion joint without the neces- sity of destroying any portion of the boxing. The boxing must be made four-ply, with two air spaces, for tanks in northern Canada. It must be three-ply, with two air spaces, as shown in Figs. 149 and 150, for tanks in New England, New York, Ontario, Michigan and Wisconsin. Two-ply boxing with two air spaces must be used in States immediately south of this section. This boxing may also be used in the Southern States or else the pipes may be wrapped with felt and tar paper and covered with canvas. Calculating Wind Stresses in a Four-Post Tower The following is one method of computing the stresses due to the wind. The problem involves a simple application of graphic statics, and depends upon the proposition that a force is fully determined when its magnitude, direction and point of application are known. Such a force may be Digitized by Microsoft® Principles and Practice of Plumbing 329 represented by a line, and the stress diagram in its simplest form represents the force as sides of a polygon taken in order. The closing side in reverse order is the resultant in magnitude and direction. The diagram shown in Fig. 151 is a typical one and the method of computation is as follows : 1 represents one bent of a 100-foot tower supporting a 40,000-gallon tank. The loadings beginning at the top of the diagram are 4,330 pounds, applied at centre of gravity of the projected surface of tank and roof; 1,750 pounds, which is equal to 100 pounds per foot or y^ the height of the top stage ; 3,500 pounds, which is- equal to 100 pounds per foot for 1/2 the heights of the top and middle stages; and ^'f^^^Ps Fig. 150 Square Frost-Proof Boxing 3,700 pounds, which is equal to 100 pounds per foot for 1/2 the heights of. middle and bottom stages. One-half the wind load is used because one bent is being considered. 2 shows the stress diagram and, as it is drawn to scale, the force resulting may be measured directly from it. 3 is a plan-view of 1 and shows the wind blowing in the plane of one bent. This being the case the axis of rota- tion will be through xx and posts r and s will take com- pression, while posts and p will take tension. The amount of the compression in post has been found from the dia- gram to be 39600 pounds. The uplift or tension in the anchor bolt at the foot of post p will be a like amount. Sup- Digitized by Microsoft® 330 Principles and Practice of Plumbing pose, however, we consider the wind blowing in some other direction and determine which is the worst case for wind loading. 4 shows the same plan-view with the wind blowing in a diagonal direction, as indicated by arrow. The axis of rotation will be through xx, and this being the case post r 3700 Scale Ilrv40ft: I Scale liaHOOOO lbs. 2 Fig. 151 Diagram of Wind Pressures jt 2jr ^ will take all the compression. The relative amounts of the compression in these two axes are shown to be as follows : In 3 let m represent the total overturning moment, then the compression in r and s is equal to-^ while in 4 the com- 1 M MV pression m r equals ^-^ - ^^ 2yV^ 4y 4y Digitized by Microsoft® Principles and Practice of Plumbing 331 In other words the compression in r in 4 is the same as the compression in either r or s, in 3, times y^ therefore the maximum compression due to the load may be taken as the amount scaled from the stress diagram multiplied by the Similarly the maximum tension in any set of anchor bolts will be equal to the maximum compression in the lee- ward post in 3 less one-fourth the total weight of the structure and tank. The stresses in the diagonal rods and struts are consid- ered to be the maximum when the wind is blowing as in 3, and therefore may be scaled directly from the diagram. Hydraulic Rams. — The hydraulic ram is an engine for pumping water, using the force stored up in a moving column of water to cause a shock or water hammer, which will take water from one level and raise it to a higher eleva- tion. By means of a ram, water at a low head may be used to raise a portion of the same or some other water to a level higher than the supply. These efficient engines will pump water 30 feet high for every foot of fall. They will operate with as little as 2 feet fall, or with a head of 30 feet, and will deliver water to a height of 500 feet and to a distance of 2y2 miles. Finally, they may be had in sizes which will deliver from 1500 gallons a day to 1,000,000 .gallons in 24 hours. A Rife Hydraulic Engine is shown in Fig. 152. This contains only two working parts, the waste valve and the supply valve, so that once the engine is set up and started, it will continue to work successfully until some parts of the valves wear so they need repair. They cost nothing for operating expenses, and are about on a par with windmills in point of economy for operating. Rife hydraulic engines are made in two types. One is the single-acting engine which elevates part of the water used for operating the ram, and the other is a double-acting engine, which pumps a pure water, using a supply of inferior water to operate the ram. The principles of opera- tion of these two types can be seen in Fig. 153, which shows th? operating parts of the engine. In the single-acting ram Digitized by Microsoft® 332 Principles and Practice of Plumbing the pipe marked h-i is omitted, and the operation of the engine is as follows : The valve at b being open, the water from the source of supply at more or less elevation above the machine flows down the drive-pipe a, and escapes through the opening at b, until the pressure due to the increasing velocity of the water is sufficient to close the valve b. At the moment when the flow through this valve ceases, the inertia of the moving column of water produces the so-called ramming stroke, which opens the valve at c, and com- presses the air in the air chamber d, until the pressure of the air plus the pressure due to the head of the water in the main, is sufficient to overcome the inertia of the moving column of water in the drive-pipe. This motion may be likened to the oscillations in a U-tube. At this Fig. lo2 Rife Hydraulic Engine instant the column of water in the drive-pipe has come to a rest, and the air pressure being greater than the static head alone, the direction of motion of the moving column is reversed and the valve, c, closed. The water in the drive, pipe is then moving backward, and with the closing of c a teniJency to ^ yacuurn is produce^ at the base of the drive-. Digitized by Microsoft® Principles and Practice of Plumbing 333 pipe; this negative pressure causes "the valve b, to open again, completing the cycle of operations. At the moment of negative pressure the little snifting valve, e, admits a small quantity of air, and at the following stroke this passes into the air chamber, which would otherwise gradually fill with water, the air being gradually taken up by water. In many machines the mistake is made of making the waste-valve, b, sufficiently heavy to overcome the static head of water in the drive-pipe. In fact, most writers on this subject, including the "Encyclopedia Britannica," state that the weight of the waste valve, b, must be greater than the Fig. 153 Section of Rife Hydraulic Ram for Pumping Water, Using Impure Water for Power pressure of the statical head of water on its under side so that it may open when the column of water comes to rest. In the machine which we are describing this would be prac- tically impossible on account of the large- area of the open- ing at b. In this machine the valve, b, is made as light as is con- sistent with the necessary strength; the negative pressure at the end of the stroke is relied upon to open the valve. When an impure water is to be used to drive the ram and deliver a pure water, the pipe, h-i, is attached to the ram as shown in the illustration, and the spring water is delivered to the ram through this pipe. The engine is then Digitized by Microsoft® 334 Principles and Practice of Plumbing double-acting, and by a proper adjustment of the relative flow of the impure driving water and the pure spring water, the engine may be made to deliver only pure water to the. supply tank. This method is used only where the supply of pure water is limited, and there is a plentiful supply of the driving water. To deliver pure water, using impure water as power, there must be at least 18 to 24 inches of fall from the spring stand-pipe to the engine. If there is a greater natural fall, it must be piped to a tank having an overflow 24 inches above the supply pipe, h-i, so there will not be a greater head than two feet to the pure water. The engine should be set on a firm, level foundation, but need not be fastened. TABLE XCII. Sizes of Rife Rams Dimensions S. 0) _c* Gallons per u <<-<.? t;''? Minute Required .« K^ •g Si It "o s J3 ti g 3 •R.6 N 01 to Operate Engine 1 10 2' 1" 3' 2" 1' 8" IM" U" 3 to 6 3 150 15 2' 1" 3' 4" 1' 8" 1^" %" 5 to 12 3 175 *20 2' 3" 3' 8" 1' 9" 2" I" 10 to 18 2 252 25 2' 3" 3' 9" 1' 9" 2^" 1" 11 to 24 2 250 30 2' 7" 3'10" I'lO" 3" iM" 15 to 35 2 275 40 3' 3" 4' 4" 2' 0" 4" 2" 30 to 75 2 600 80 7' 4" 8' 4" 2' 8" 8" 4" 150 to 350 2 2500 *120 12" 5" 375 to 750 2 3000 tl20 8' 9" 9' 6" 3' 8" 2-12" 6" 750 to 1500 2 5500 •Single. tDuplex. Dkive-Pipe for Ram. — The length of drive pipe is gov- erned by the ratio of fall or driving head to elevation or pumping head. If the drive pipe is either too long or too short, the automatic supply of air will be interfered with and the efficiency of the engine impaired. The drive pipe must be laid in a perfectly straight line, without bends or curves, except where the pipe enters the engine, and this should be made by bending the pipe. The upper end of the drive pipe where it takes in water ought to be far enough Digitized by Microsoft® Principles and Practice of Pluwibing 335 below the surface so it will not take in air. It should be submerged one foot or more, and the entrance protected by a good open strainer. The delivery pipe can be laid with the necessary fittings, according to the usual practice with water pipes. In Table XCII can be found the size of drive pipe, dimensions and quantity of water required to operate differ- ent sizes of Rife Rams. In Table XCIII can be found the sizes of Gould rams and the length of drive pipes to operate them. These lengths may be accepted as approximations for usual con- ditions. TABLE XCIII. Conditions and Sizes* of Gould Rams To Deliver Water to Height of Place Ram under Conducted through 20 ft. above Ram 30 ft. above Ram 40 ft. above Ram 50 ft. above Ram 60 ft. above Ram 80 ft. above Ram 100 ft. above Ram 120 ft. above Ram 3 ft. Head of Fall 4 ft. Head of Fall 5 ft. Head of FaU 7 ft. Head of Fall 8 ft. Head of Fall 10 ft. Head of Fall 14 ft. Head of Fall 17 ft. Head of Fall 30 ft. of Drive Pipe 30 ft. of Drive Pipe 40 ft. of Drive Pipe 50 ft. of Drive Pipe 60 ft. of Drive Pipe 80 ft. of Drive Pipe 100 ft. of Drive Pipe 125 ft. of Drive Pipe *Any size Kam may be operated under these conditions and will afford the following approximate delivery : No. 2 requires 2 to 3 gals. No. 3 requires 2 to 4 gals. No. 4 requires 3 to 7 gals. No. 5 requires 6 to 12 gals. No. 6 requires 11 to 20 gals. No. 7 requires 18 to 35 gals. No. 8 requires 30 to 60 gals. per minute and delivers per minute and delivers per minute and delivers per minute and delivers per m'inute and delivers 10 to 15 gals, per hour 10 to 20 gals, per hour 15 to 35 gals, per hour 30 to 60 gals, per hour 65 to 100 gals, per hour per minute and delivers 90 to 175 gals, per hour per minute and deUvers 150 to 300 gals, per hour Efficiency and Capacity of Rams. — The question of efficiency of hydraulic rams has been much discussed, and such authorities as Rankine and D'Aubisson differ consider- ably in their calculations. Rankine's formula is : (Q-q) H' where Q is the quantity of water flowing per second in the Digitized by Microsoft® 336 Principles and Practice of Plumbing drive-pipe ; q, the quantity flowing per second to the stand- pipe through the discharge pipe; H, the height from the escape valve to the level of the reservoir which feeds the drive-pipe; and k, the difference in the level of the water- supply reservoir and the water in the stand-pipe. D'Aubis- son states the formula for efficiency as E= q^H + h) QH D'Aubisson's is the correct one, considering the mechan- ism as a machine receiving energy at one end and delivering it at the other, while if the machine is considered as elevat- ing water only from the one reservoir to the other, Ran- kine's formula is the correct one to use. The capacities of Rife Rams can be found in Table XCIV. The size of ram to use is easily determined by either of the two tables given. For instance, opposite each ram the maximum and minimum amount of water this ram will use will be found, and by simply multiplying either the maxi- mum or minimum amounts the ram uses by the factors found in the table of capacities, will give either the mini- mum or maximum amount this particular ram will deliver. Take a No. 20 engine for example. This ram will use from 10 to 18 gallons a minute. Now, then, if it is found that 15 gallons of water is all that is available, then multiply that amount by the factor found in the table of efficiencies, which will give the amount of water that will be delivered. The factors in the table are based on the ratio of power head or fall for the drive pipe, to the height the water must be elevated. This and the efficiency developed are shown in connection with the example worked out, in the corner of Table of Capacities. It will be noted that the number of gallons is 1400 per minute, which is multiplied by 192. Now, opposite 10 foot fall and under 50 elevation, this number 192 is found. This is a ratio of 5 to 1. In looking at the bottom of page giving the efficiencies, it will be found that the ratio from 1 to 3 up to 1 to 18 equals 66 2/8% efficiency, so that in determining the amount this ram will deliver, it was figured on 66 2/3% efficiency. A ram, if installed Digitized by Microsoft® Principles and Practice of Plumbing 337 OS s >-, d. ■p •^H y CQ a §■ K u -!ji00C0'*iO-G0Oi-l-asi-icv3ict~-oco b-COO(M'*C000O-^00(NCDO'^G0G0'^»O T-H T-i 1-1 T-H i-H (N (N (N (N CO CO J* t-»CasC^cDO"^I>-if3C^OI>-00C0c0i0O»0 COiOCDOOOir-KMCOCOOiCN-^OOOTtHt^COCD ^^^^^C^{>jC<1COCOCOtH'^ ■^CO-^0^-COiO-^'<*CO[MOOCOOOiOO C-01COt^C-(N TflcDOOOtNiCiOOOOiO cD0i(NcD0:iC01>.OcDC0O l-^rH.-^l^^^^lC0C0-!*^>O 1— li— I(NC0C0'^"^>J0 00 (N <^ lO !>) lO CM CI >0 "* CO O 1— 1 i-H C^ CO Tt< iO (N r-l(N O 05 O CO -^ 1-1 CO'^ IC ■a .61) ■9 s a I" s a no, h Vp-I ■a '5'-' ■a a o a oc o d ^ 1)5 o 00 0) o S oj ho; i>i a aii I SB I a ^ 0=5 o o p,'^'^ -"■" ao o O O rt P P 00^00 A C4 I. Cj 8J t( t4 M ^ t^ bJ rt"*^ OS «l O Om o o Digitized by Microsoft© 338 Principles and Practice of Plumbing under 3 foot fall and 75 foot elevation, which is a ratio of 1 to 25, the efficiency table shows that 50% efficiency would be developed where the ratio is 1 to 23 up to 1 to 30. Pneumatic Water Supply. — The pneumatic system of water supply utilizes the compressibility of air to force water out of a tank to any required elevation. When water is pumped into an empty tank, the air already in the tank is trapped there and compressed in the upper part, the water occupying the lower part of the tank. All pipe con- nections are made near the bottom of the tank so the air cannot escape, then, when a faucet is opened, the com- pressed air within the tank forces the water out at the fixture. The air in the tank would soon become exhausted, how- ever, if more air were not supplied in proportion to the water pumped into the tank, and to keep up the supply of air a small air compressor, "snifter" valve, or some other equally positive device must be employed to pump air into the tank. The quantity of water that a tank will deliver at a given pressure and elevation depends on the proportion of air and water in the tank. If the air cushion is of small volume, the pressure drops so rapidly when water is drawn, that it becomes necessary to pump in more water, thus in- creasing the pressure by compressing the air into still smaller space. But this does not increase the volume of air. The pressure of air in tanks when partly full of water, can be seen in Table XCV. TABLE XCV. Proportions of Air and Water in Tanks Amount of Water Pumped in Tank If Tank Contained only Atmosphere, Pressure will be If Tank is First Pumped to 10 Pounds Pressure with Air the Pressure will be 1/4 full of Water 2/5 full of Water 1/2 full of Water :V5 full of Water 2/3 full of Water 3/4 full of Water 5 Pounds 10 Pounds 15 Pounds 22 Pounds 29 Pounds 45 Pounds 18 Pounds 26 Pounds 34 Pounds 47 Pounds 58 Pounds 83 Pounds It will be noticed from the table of pressures that where Digitized by Microsoft® Principles and Practice of Plumbing SSd only the atmosphere in the tank is trapped and compressed, the volume of air is not sufficient to deliver under pressure all the water contained in the tank. For average require- ments the best results are obtained when the proportion two-thirds water and one-third air is maintained. At this proportion the atmosphere in the tank will be compressed to a point where it will exert a pressure of 29 pounds per square inch. Now, if water be further drawn off, until the pressure falls to 5 pounds, the tank will still be one-quarter full of water, and the pressure of air will not be sufficient to de- liver it to any fixture higher than the tank itself, and that one-quarter tank of water will not be available. Had 10 pounds of air been pumped into the tank first, the pressure would be 58 pounds at the proportion of two-thirds water and one-third air, and this pressure would force practically all the water out of the tank, having a pressure of 18 pounds to force out the Ikst quarter of water. Another advantage of an initial air pressure of 10 pounds lies in the fact that a smaller tank can be used for a given installation. For instance, if a 750-gallon tank is first pumped to 10 pounds pressure with air, it will deliver as much water at equal pressure as would be available from a 1000-gallon tank without the additional air pressure. Digitized by Microsoft® 340 Principles and Practice of Plumbing CHAPTER XXXI PLUMBING FIXTURES Classification of Fixtures Plumbing Fixtures. — Plumbing fixtures are here considered solely from a sanitary point of view. Types are discussed but not the various modifications or makes. Those may be seen in the show rooms of plumbing supply houses or very natural illustrations of them can be seen in plumb- ing supply catalogues. Plumbing fixtures are receptacles for soil and waste water from which it is discharged into the drainage system. There are several classes of fixtures, each fixture being classified according to its use. Thus : Soil fixtures include water closets, urinals, school sinks, bidets, slop sinks, and all other fixtures into which soil is discharged. Scullery fixtures include kitchen sinks, pantry sinks, laundry tubs, and any fixture used in the preparation of meals or washing of household goods. Laving fixtures include wash basins, bath tubs, needle, shower and spray baths, and any fixture used for cleansing the person. Clean water fixtures like drinking fountains form a group by themselves. Requirements of Sanitary Fixtures. — To be per- fectly sanitary, plumbing fixtures must be made of some non-absorbent, non-corrosive material that is not easily cracked, crazed or broken, and that has perfectly smooth surfaces to which soil will not adhere so firmly that it can- not be removed by a flush of water. Outlets of fixtures should be as large or larger than the waste pipe and should be unobstructed by strainers or cross-bars, so that the waste pipe will receive a scourging flush at each discharge of the fixture. Fixtures that are provided with stoppers for the waste outlet generally have overflows to prevent water overflowing the fixture when the stopper is in place. There is no reason why lavatories and bath tubs should have over- flow channels, however. They seldom are of sufficient size to carry off the inflow of water, so they do not perform the Digitized by Microsoft® Principles and Practice of Plumbing 341 function for which intended. Often they leak when water rises to their level, and at all times they are unsatisfactory channels, which might well be dispensed with. Fixtures should be set open, that is, perfectly free from enclosing woodwork or other casings that would cut off light and air. They should be well supplied with water for flushing, and in public places the walls and floor where they are set should be lined with some non-absorbent material. Requirements of a Sani- tary Closet. — To be efficient and san- itary, a water closet should be made of porcelain enameled iron or of vitreous ware, and must be absolutely free from working mechanism within the receptacle. It must contain a suf- ficient depth of water to com- pletely cover any excremental matter deposited in it, so as to prevent odor. It must have no surfaces that can become soiled or that are not thor- oughly water scour- ed every time the fixture is fiushed. It must be supplied at each discharge with a sufficient volume of water to remove the entire contents of the bowl and trap and replace it with fresh water. The water should be dis- charged into the closet suddenly, with force, and in a large volume, and the closet must be connected to the soil pipe with a perfectly tight and permanently tight floor flange, that is flexible to yield Witli ghrinkage, settJenjent, and Fig. 154 Hopper Closet Digitized by Microsoft® 342 Principles and Practice of Plumbing other movement of the building. No closet can be sanitary which depends on a putty-joint for a seal. Hopper Closets. — The simplest form of water closet is a hopper closet, shown in Fig. 154. It consists of a fun- nel or hopper-shaped bowl fitted with a flushing rim or pipe- wash connection. This type of closet contains no water in the bowl and the converging sides are dry and present the maximum surface to be soiled. Hopper closets are installed principally in exposed places where other types of closets that contain water would be damaged by the frost. When thus installed the closet trap and water supply valve are located in a pit below frost level, and after each flush of the fixture the water is automatically drained from the flush pipe down to the valve. When fitted up in this manner the entire inner surface of the pipe from the hopper to the trap, sometimes becomes covered with a coating of slime that in warm weather gives off a very disagreeable odor. At their best they are unsanitary and objectionable, and should not be permitted. Hopper closets located in warm places should be flushed from a tank or flush valve and should have the trap placed as close as possible to the closet bowl. Number of Fixtures Required. — The number of plumbing fixtures required depends somewhat on the type of building to be equipped. In Table XCVI will be found the number of fixtures of various kinds found sufficient to serve 100 patients in state hospitals for the insane in New York State. TABLE XCVI. Plumbing Fixtures Required in Hospitals Number required per 100 Patients In Men's Ward In Women's Ward Water Closets 8 4 10 2 1 9 Urinals 9 Rain Baths .... 2 Bath Tubs 1 The number of toilet fixtures required in school build- ings c^n b§ found in T^bie xcyii. Digitized by Microsoft® Principles and Practice of Plumbing 343 Laundry Fixtures and Connections. — The follow- ing list shows the fixtures installed in the laundry of the New York Ambassador, and the steam water waste and electric connections required : No. Kind of Machines 42x72" Washers 42x36" No. 12 Washers 40" Overbelt Driven Extractors . 28" Extractor 100 Gallon Soap Tanks Wood Truck Tubs 48x54" Clothes Tumbler . 42x60" Hot Air Tumbler. 50 Gallon Starch Cooker Zinc Covered Starch Table. . . 18" C. & C. Starcher 3 loop 9' Conveyor Dryroom. No. 1 C. & C. Dampener. . Heubsch Spray Dampener. Bishop Dampening Press . . 30x120" Big Two Ironers. . 06" Handy Type Ironer. . . Connections 38" Troy-Prosperity Presses No. 361 Hagen-Keystone Bosom Press . Type "C" Double Cuff Press Type"C" Single Neckband Press. 24" Steam C. & C. Ironer 30x96" Finishing Table No. 624 Shaw Collar Shaper Zeidler Improved Seam Dampener. 4M" Porcelain Hot Tube Shaper. . Shirt Ironing Table with outfit. . . . Skirt Ironing Tables No. 666 Gilbert Suspension Arms. . No. 6 Electric Irons Box Curtain Dryer 3 Compartment Stationary Tub . . Flatwork Tables. Hot and Cold Water, Steam and Electricity Hot and Cold Water, Steam and Electricity Connections for drain onlj', and electricity Connections for drain only, and electricity. Cold Water and Steam Con- nections. None. Electricity. Steam, Return with Trap and Electricity. Steam only. Steam only Steam, Return with Trap & Electricity. Steam, Return with Trap & Electricity Electricity. Water and Steam. None. Steam, Return with Traps and Electricity. Steam, Return with Trap and Electricity. Steam, Return with Trap Steam, Return with Trap and Electricity. Steam, Return with Trap. Steam andReturn with Trap. Steam, Return with Trap and Electricity . None Electricity Electricity Steam Connections. Electricity for Iron. Electricity for Irons. Electricity. Electricity Steam, Return with Trap. Hot and Cold Water and Steam. None. Digitized by Microsoft® 344 Principles and Practice of Plumbing TABLE XCVII. Number of Toilet Fixtures for Schools Number of Pupils Kind and Number of Fixtures Water Closets Urinals Girls Boys Kindergarten Boys Under 30 Children. . . . 50 ■ 70 100 150 200 300 2 2 4 5 6 8 12 1 2 2 3 3 4 5 2 3 3 4 5 6 8 2 3 4 5 7 10 15 Siphon-Action Closets. — The most satisfactory- closets are those which operate on the siphon principle, and contain sufficiently large bodies of water in the bowls to submerge and deodorize anything discharged into them. In addition they ought to be so constructed that there will be no dry sur- faces liable to foul or to which soil can adhere. The siphon-action closet shown in section in Fig. 155 is distinguished from all other types of siphon- acting closets by the hori- zontal portion of the out- let leg of the trap under- neath the bowl. The trap instead of having a straight outlet, is more or less offset and curved as in all siphon-acting closets, so that water overflowing from the bowl will rarify the air to such an extent as to induce siphonic action to carry the contents from the bowl. There is considerable dry space above the water line in the bowl of this closet, and it is the least satis- factory of all the siphon-action types. Indeed, the dia- phragm forming the upper part of the short leg of the trap Fig. 155 Section of an Ordinary Siphon-Action Closet Digitized by Microsoft® Principles and Practice of Plumbing 345 Fig, 156 Section ot a Reverse Trap Siphon-Action Closet in the bowl is so completely above the water, and so in the way, that it cannot escape being soiled more or less. •Reveese-Trap Siphon-Action Closets. — What is known as the reverse-trap siphon-action closet is shown in Fig. 156. The outlet leg of the trap in this type is quite similar to the outlet leg of the siphon- jet closet, which it resembles in general appearance. It is a better appearing and more satisfactory closet in every way than the or- dinary siphon-action clos- ets. As a rule they are smaller than the siphon- jet closet, contain less parts, and consequently cost less, while at the same time they rank a close second. Siphon-Jet Closets. — A siphon-jet closet is shown in Fig. 157. This closet is vitreous, smooth, impervious and contains a large body of water in a receptacle so shaped that it cannot easily be soiled. In operation it is almost noiseless. The operation of a siphon- jet closet is as fol- lows: The flushing water parts upon entering the closet; some of it enters the flushing rim and cleanses the bowl, while the rest of it flows through the jet, and ejects the water from the closet. The ejected water enters the outlet leg of the closet, which is usually so constructed that the outlet can be easily filled with water or the air rarified. When the outlet leg becomes filled with water it acts as the long leg of a siphon, and thus siphons the contents of the bowl Fig. 157 Sipbon-Jet Closet Digitized by Microsoft® 346 Principles and Practice of Plumbing into the soil pipe. Once the siphonic action is started it continues until the bowl is empty and enough air has en- tered the trap to prevent further siphonage. The closet is then refilled by the after-wash from the tank or flush valve. As the contents of a siphon- jet closet are ejected by the pressure of the atmosphere on the surface of the water in the bowl, it follows that a considerable volume of air from in and around the closet will be carried into the soil pipe at each discharge, thus carrying off the most impure air from around the closet. Some siphon-action closets are now made with a jet, so it is hard to distinguish one type from the other. However, the siphon-action is smaller, and usually has a side flush connection, while the siphon-jet has a top connection. One objection to the siphon-jet closet is the liability of shrinkage cracks or fire cracks which allow drain air to escape into the room. On account of the difficulty of manu- facture, a large percentage of siphon- jet closets have this concealed defect. Wall-hung closets are not siphon-acting. They are blow-out closets from which the contents are ejected or blown out by means of a jet of water. Closets are better installed resting on the floor than hung from wall or parti- tion. Closet Floor Flanges.— No closet can be considered perfectly sanitary which depends upon a putty- joint, gasket or slip-joint for a seal. The one bad and weak spot in past practice has been the point where the water closet is connected to the soil pipe. Experience has shown that where a putty-joint, or a rigid gasket joint or slip-connec- tion are used, the closet is either broken or the connection destroyed within a short time after the closet is installed. This is due to the settlements and shrinkages of the build- ing, or the settlements, expansions and contractions of the drainage system. The only sanitary connection for a water closet is a joint which is not only tight when it is put in, but will remain so during all the changes and movements which take place within the building. As many as 150 closets in Digitized by Microsoft® Principles and Practice of Plumbing 347 one building have been broken on account of rigid connec- tions, and where the closets are not broken the floor joints are. Every closet connection, then, should be provided with a flexible fitting of some kind to protect the closets, and the floor flange itself is preferably of the metal-to-metal kind. It is obvious that this important connection should be as perfect as it is possible to make it. This can be assured only when the flange is made in the factory and tested be- fore being sent out. A gasket connection is not a tight con- nection made so in the factory, but is merely the raw materials sent out for the plumber, if skillful enough, to make the joint tight. As it is almost an impossibility to make a tight joint using a rough gasket against a rough and irregular earth- enware surface, the ^ ^ plumber falls back on putty or paste of some kind to make the joint tight, us- ing it with the gas- ket, and to keep the joint tight until it has passed all tests. Such joints are not lasting, however, al- though they are fairly satisfactory when used in connection with a flexible fitting. The only sanitary types of flanges recognized as such are the metal-to-metal flanges. One flange of this type, known as the Standard Ball Joint, is shown in section in Fig. 158. This is what would be called a ground joint made on the well-known ball-and-socket principle. It is made tight in the factory, and when used in connection with a flexible fitting is one of the best closet floor flanges on the market. Another metal-to-metal closet floor flange, known as the Pres-0-Flex, is shown in Fig. 159. This is a flexible con- nection, so constructed that it will stretch or collapse to Fig. loS Stantlarcl Ball Joint Digitized by Microsoft® 348 Principles and Practice of Plumbing take care of any reasonable settlement, shrinkage, or other movement of the piping or building. This flange, like the Ball- joint, is made tight at the factory, and tested before being sent out, which ought to be required of any flange before specifying. If the maker is not willing to stand back of his goods for five years, the specifying architects cannot be expected to have much confidence in it. Flush Tanks. — Water closets should always be flushed with water from flush tanks, or through specially con- structed flush valves. There are two reasons for these requirements : First, the flush pipe or flush valve will be of Base of^C/ase/\ Fig. 159 lletal-to-Metal Floor Flange sufficient size to supply a large volume of water in a short period of time, thus insuring a good flush ; second, the tank can be proportioned or the flush valve regulated to furnish a certain quantity of water at each flush. Flush tanks are made with capacities ranging from 6 to 12 gallons. In large city apartment houses, hotels and like buildings, where a considerable volume of water is gen- erally flowing through the house drain, tanks of smaller capacity may be used than would be required in private houses or in large country institutions which are located a considerable distance from a trunk sewer or other place of Digitized by Microsoft® Principles and Practice of Plumbing 349 sewage disposal. The reason for this is that in large city buildings if a sufficient volume of water is provided in closet tank or flush valve to discharge the contents of a closet into the soil stack, it will fall by gravity to the house drain, where assisted by the flowing water in the drain, it will be carried to the street sewer. The functions of the flushing water is thereby performed and water economized at the same time. On the other hand, assistance from other sources cannot be depended upon in private buildings and country institutions, so a sufficient volume of water must be provided that will carry the contents of the closet bowl all the way to the street sewer. Closet tanks with siphon flush valves are generally used in connection with washdown, and hopper closets, while slow-closing flush valves are used with siphon-jet combinations. Flush Valves. — Flush valves are mechanically suc- cessful in operation, but are suitable only for buildings sup- plied with water from a storage tank. This does not mean they will not operate on direct city pressure, or that there is any sanitary reason for so installing them. The trouble lies in the large size of pipe required. If all the closets in a large city were served direct from the city mains through flush valves, the size of mains would be excessive. Flush valves cannot be successfully used unless there is sufficient volume and pressure to operate them. For high- pressure service they require a head of at least twenty feet; where this head is unavailable, special low-pressure valves should be used. Flush valves can be regulated to discharge almost any desired quantity of water at each flush of a fixture. The usual amounts vary from 4 to 8 gallons, which are dis- charged in from 3 to 6 seconds' time. If the service pipe is not large enough to supply this quantity of water within the required time a flush valve cannot be successfully used. Size of Pipes for Flush Valves. — Care must be tdken when installing flush valve systems to proportion the pipes so each valve will have an adequate supply of water. No pipe in the system should be smaller than 1 inch in diameter, ^jid three to five closets is the greatest number a 114,-inQh Uigitized by Microsoft® 350 Principles and Practice of Plumbing pipe will supply at the average pressure of 30 pounds. When there are more than four closets in an installation, a safe rule is to allow in the supply main the capacity of 34-inch pipe for each closet. When the large battery of closets is at a place of public assemblage like a ball ground, the allowance should be midway between % and 1 inch for each closet. When there are a greater number of closets than 100 in an office building, it can be assumed that all will not be operating at the same time and an allowance of the capacity of %-inch pipe be made for all the closets or of a 1-inch pipe for the greatest probable number that will be operated simultaneously. Example — What size of water main will be required to supply twenty-one flush valves? Solution — Required a pips having the capacity of twenty-one %-inch pipes, and Table LI shows that a 2%-inch pipe has a capacity of 23.3 ■')4-inch pipes, therefore a 2%-inch pipe should be used. The sizes of pipes required for flush valves determined by the foregoing rule are based on the assumption that a main of adequate size is provided for the group, so the length of run from the main to the first flush valve will not be over twenty to forty feet, depending on the pressure, the range of pressure being from twenty to sixty pounds. If there is a long run of pipe from the source of supply to the group of closets to be served, the main must be propor- tioned to take care of the additional frictional resistance in the pipes. The capacity of a 1-inch pipe for each closet in the group will take care of the friction. Table XCVIII gives the size of pipe required for a single flush valve installation, it being understood, of course, that as the number of water closets increases, the ratio of the size of pipes becomes smaller, due to the fact that the supply piping must only be large enough to take care of the maximum number of closets that are liable to be oper- ated at one time. School Sinks and Latrine Troughs. — School sinks or latrines are sometimes installed in schools, barracks, hospitals and like institutions. They are very unsanitary in Qo?istructiop m^ violate almost every known sanitary Digitized by Microsoft® Principles and Practice of Plumbing 351 requirement for a plumbing fixture. Oftentimes they are made of plain iron which corrodes and becomes foul smell- ing; frequently they are encased in woodwork which shuts out light and air, and that becomes filthy from deposits of soil and foul from saturation of urine; they furnish breed- ing places for bacteria and vermin, and worst of all, some- times retain for hours rank and putrid substances that should be immediately removed from sense of sight and smell. Water closets are made that are particularly adapt- ed for hospital barracks, schools and public toilet rooms, where great strength and durability are required in a fix- ture, and one that can easily be cleansed with hose and broom without damage to any part. These closets can be had in washdown or siphon- jet types. TABLE XCVIII. Size of Pipe for Single Flush Valve Minimum Pres- sure at the Flush Valve Total feet of supply pipe from the flush valve to the street main or storage tank S 10 20 30 40 60 80 100 150 200 Size of pipe for one water closet 5 Pounds 114 IV?. m. IM 2 2 2 2V^ 2H 3 10 Pounds \% W?. m ly?. 2 2 21^ 2M 20 Pounds IK IJC IK ly?. ly?. 1K« 2 2 30 Pounds 1 IK IK IK ly?. m 1J4 ly? 40 Pounds 1 IK IK IK ly?. ly?. m 60 Pounas H 1 1 IK IK IK ly?. ly?. 80 Pounds 'A M 1 1 1 IK IK IK iVi Add 10 feet for each 90 degree fitting. Ventilation of Closet Compartments. — Rooms in which water closets are situated should be well ventilated to insure a frequent change of air. This requirement is abso- lute in large toilet rooms containing many washout or other non-deodorizing closets. A method of ventilating closet compartments is shown in Fig. 160. The separate flues in this system should never be less than 6 inches in diameter, and when possible to place a small steam or hot water coil in the bottom of each flue, the direction of the current of air is made positive. Ventil- ation flues from different compartments should extend Digitized by Microsoft® 352 Principles and Practice of Plumbing separately through the roof or be joined at considerable distance from the rooms. When joined to flues from ad- joining rooms they serve as sound conductors from one room to another. In case the water closets are of the siphon type, or of any design which contains a large volume of water and but little soiling surface, ventilation of the room will be all that is necessary, the vent registers being located back of the closets. If for any reason the toilet room is so located that the air is heavy and the ventilation consequently sluggish, or if it is approached by descending a few steps into the room, each closet of whatever type, should be vented through a local vent having at least eight square inches of area, and connected to a shaft having a positive draft insur- ed by mechanical means. In many cases it is better to vent the closets, or the room through the local vents of the closets, than to vent the rooms through registers located back of the closets ; but as a rule it is better to vent the closet compartments used by girls through registers back of the closets, than to vent them through local vents in the closets. Urinals. — Urinals should be made from the least absorbent and least corrosive of materials, and all exposed connections, walls, floor and partition, should be equally non-absorbent and non-corrosive. If the urinals or sur- roundings are absorbent they will soon become saturated with urine and emit a most pungent and disagreeable odor. If made of corrosive materials they will be energetically attacked and destroyed by the urine. Stall urinals of Fig. 160 Toilet Eoora Ventilator Digitized by Microsoft® Principles and Practice of Plumbing 353 vitreos ware are the most satisfactory, or the least objec- tionable, and are best flushed with a foot valve. Slop Sinks. — A slop sink at which to draw water for scrubbing and general cleaning and in which to empty soiled scrubbing water and other slops, should be provided in every building. In a resi- Hush p/pe /romTank dence a slop sink on the sec- ■^ *-• ond floor will often save the cost of the fixture by pro- tecting the bath tub and water closet from the wear and tear incident to using them for drawing and emptying scrub water and slops. Hotels, office build- ings and other large institu- tions should have one or more slop sinks on each floor, and in hospitals slop sinks are indispensable on all floors. It is evident from the uses of a slop sink that it should be supplied with hot and cold water, and in addi- tion, hospital slop sinks should be flushed from an overhead tank or from a flush valve. The contents of bed-pans are emptied into hospital sinks, so that to a certain extent they partake of the functions of a water closet and must therefore be made and operated like one. The outlet to slop sinks should be unobstructed by strainers or cross bars, so the waste pipe will receive a good flush. In the case of hospital sinks this requirement is absolute, on account of their dual function. As they are in the nature of water closets they should like- Fig. 161 Hospital Slop Sink Digitized by Microsoft® S54 Principles and Practice of Plumbing wise' be provided with flexible metal-to-metal floor flanges. Slop sinks are usually made 10 to 12 inches deep and from 20 to 24 inches square. They are made both of iron and of porcelain. Iron slop sinks are made either plain, galvanized or porcelain enameled. Hospital Slop Sinks. — A hospital slop sink is shown in Fig. 161. The bowl of the sink is shaped like a closet bowl converging toward the outlet, which is large and unob- structed by a strainer. The sink is flushed through a flush- ing rim, a, from a tank overhead or from a flush valve, and is also supplied with hot and cold water through a combina- tion cock, 6. The slop sink is also fitted with a cleansing jet, c, to which the water may be turned on by hand valves at the back of the sink or by the foot valve, d, on the floor. The nurse or orderly empties the contents of a bed-pan on the right side of the sink which is flushed from the tank, the bed-pan is then inverted and held over the cleansing jet in the left side of the bowl to be washed. Hospital Lavatory. — A lavatory suitable for hospital operating rooms is shown in Fig. 162. A hospital lava- tory differs from a common type only in the manner of operating the supply and waste valves. This is accom- plished by means of levers attached to the floor and oper- ated by foot. A hospital lavatory should be supplied with Fig. 162 Hospital Lavatory Digitized by Microsoft® Principles and Practice of Plumbing 355 hot and cold water through a combination cock so that water of any desired temperature can be drawn. Shower and Rain Baths. — For use in private homes, public and semi- public bathing establish- ments, shower and spray- baths, Fig. 163, are very suitable. They are always ready and permit the bather to wash in running water. Many designs of rain, shower and needle- shower and spray baths are made, some simple and some elaborate. Stock fix- tures can be supplied to fill most any requirement. Mixing chambers, a, should be used with shower baths so the water can be tem- pered to the required tem- perature before using. When a mixing chamber is omitted, the supply valves should be so arranged that hot water cannot be turned on without also turning on the cold water. This ar- rangement of valves will prevent bathers from being scalded by hot water. Shower baths are often a failure, not because the shower baths are not prop- erly made, but because they are installed without a suf- ficient supply of water, or without sufficient pressure. Some- times they are lacking in both pressure and volume. As a rule it may be stated that no large needle shower and spray Fig. 163 Needle Shower and Spray Bath Digitized by Microsoft® 356 Principles and Practice of Plumbing bath will work satisfactorily with a less pressure than 20 or 25 pounds, and a supply of the full size of the fixture con- nections capable of delivering from 30 to 40 gallons of water per minute. Even then they will not work unless the whole water supply system is so proportioned that there will not be a drop of pressure below the 20-pound limit when other fixtures in the building are being operated. Where showers are fitted up in battery, the supply mains to them must be sufficiently large so the throwing into service or cutting out of either the hot or cold water of one will not affect the others. Small pipes are the cause of many fail- ures of showers. Unless the supply mains are properly proportioned, when a bather has the water for his shower tempered to the right degree, it is suddenly made either hotter or colder by another shower being turned on or shut off. This will happen even when mixing valves are used, although the fluctuation of temperature will not be notice- able if the system is rightly proportioned, or a Leonard type of thermostatic mixing valve used. A hand on this valve is set at the temperature of water wanted and the variation from that temperature will not be more than two degrees. A great mistake in institutional work where a number of showers are to be used, is in getting the shower heads too large in diameter and with the perforation or holes too large and too numerous. This is unnecessary from a prac- tical standpoint, for a small shower head with small holes will give as good results; and it is wasteful from an eco- nomic standpoint, for it will use too much water, part of which has to be heated. By actual measurement, it was found that one shower head was using water at the rate of 35 gallons per minute. In practice it is found that a shower head 4 inches in diameter, having 70 holes of about 1/32-inch each, is large enough for all the ordinary requirements of institution or other shower work, and is at the same time particularly sav- ing of water. This size shower head operates very satis- factorily at a low head or pressure, owing to the increased velocity obtained by the use of small spray holes. It is found that a %-mQh pipe with wat^r at 50 pounds Digitized by Microsoft® Principles and Practice of Plumbing 357 pressure will supply six 4-inch shower heads each having 70 holes of 1/32-inch diameters. That is the very smallest supply for that number, and, even at the pressure stated is inclined to be small. That is, it would be better for six shower heads of the kind described to provide larger sup- plies, and as the pressure decreases, increase the size still more. Digitized by Microsoft® 358 Principtes and Practice of Plumbing CHAPTER XXXII SWIMMING POOLS Construction of Swimming Pools. — The structural features of a swimming pool depend somewhat upon the place where it will be located, and particularly on whether it will rest on solid foundation or be suspended from the steel floor beams of a building. A swimming pool, or plunge bath, built on a solid foun- dation of earth or bed rock can be seen in Fig. 164. It is made of reinforced concrete with walls of a thickness pro- portional to the size and depth of the tank. The concrete would be poured wet, and mixed with an integral water- ^ o '"' Burlap ^ c ^ Wote^ proof mg^ Ertameted Br/cff y. ^ Waterproofing '■' ^»^^ ."J " a . ' '•■ft' »".•■' '^ Flg. 164 Plunge Tank proofing compound. In addition, the bottom and walls would be water proofed by applying a coating of asphalt, or some other good water proofing material, about i/^-inch thick, laid hot in burlap of 8 to 12 ounce weight, then while still hot covered with another i^-inch of the water proofing Digitized by Microsoft® Principles and Practice of Plumbing 359 material and burlap pressed and broomed to a proper bond. Where pipes pass through the walls or bottom they must be made water tight by means of lead flashings built into the concrete, and water proofing. After the walls have been water proofed, the tank may then be lined with an 8-inch wall of glazed brick. A 4-inch wall may be used if there is no danger of back pressure from Digitized by Microsoft® 360 Principles and Practice of Plumbing ground water at the site; or instead of using brick, the water proofing material may be laid between two walls of concrete, and the inner surface lined with tile. The bottom of a swimming pool is made sloping, so there will be good drainage towards one point, and so the tank will be deeper at one end than at the other. In small tanks the depth at the shallow end will average between 31/4 and 4 feet, and 5 to 6 feet at the deep end. In large plunge baths a depth of 7 to 8 feet will be found at the deep end. *■)■•■ s^i-;?;'^ ;i"S^e ■»■■'.':„■..- •V-?Vi. .'^:^'> ir.ff'j^ ■i-^.-V. ' a P-.- • ("' *>■;>■"• ■■»■■.';•.■''■''■ ". ^:V".;^ Mix ,a.■»^T•p■.^>^r.■.■:^:. .^».:eVV.>.:i..-i;- Fig. 166 Waste Connected to Plunge Tank A gutter is shown at the surface level of the water. This gutter extends around all sides of the pool, serving as an overflow. Also by turning on the water the top scum or film can be skimmed off, thereby carrying off floating impurities from the surface. A railing is shown about a foot below the level of the gutter. A hanging or suspended swimming pool is shown in Fig. 165. The details of construction are very clearly Digitized by Microsoft® Principles and Practice of Plumbing 361 shown. The bearing walls of the building must be made strong enough to sustain the tremendous weight of the pool when it is filled with water, and double I beams will be required at frequent intervals to support the frame work of the tank. The framework is made of I beams and channel irons, and inside of the framework a steel tank is built as a casing for the plunge. This tank must be made of suf- ficiently heavy plates to sustain the weight of lining and water without bending or yielding between supports, The inside of the tank is water proofed and lined as explained in the case of tanks resting on the ground. The waste and overflow connections to a swimming pool is shown in Fig. 166. The overflow pipe is made large enough to carry iConcrefe. off as much water d|»g^ as can be dis- mMk^i Flattened »:«-a.2:^-j<--A.^-^,-.., ■:^>vA-.^,-«-.rf.:>;A ^Atf:;^' i-wi-'d--"?;: Wate^r proof ing> ■ass "head. Fig. 167 Hand Rail Support charged into the tank by the sup- ply pipes, and the waste pipe is made large enough to empty the tank inside of an hour. Some times swimming pools are located below the level of the street sewer, in which case the contents of the tank must be elevated to the sewer when emptying by means of pumps. Ordinarily a centrifugal pump direct- connected to an electric motor is used for this purpose. One method of attaching anchors for the support of hand rails is shown in Fig. 167. A piece of pipe flattened at one end to keep from turning and threaded and bent at the right angle, is built into the wall. Then when the glazed brick or tile are in place the rail can be finished by putting the cast brass skew plates on the anchor pipes, then screwing into place the cast brass ring heads. Heating Water for Swimming Pools. — The water in Digitized by Microsoft® 362 Principles and Practice of Plumbing a swimming pool is generally heated by circulating it through a steam water heater. Sometimes when the pool is at a higher level than the boiler room, a simple gravity sys- tem of heating by means of a coal water heater such as is shown in Fig. 168 is employed. The cold water supply is connected to the heater, and by-passed to the pool, so water can be supplied direct or through the heater. In very small tanks only one inlet and outlet connection will be necessary, but in large tanks multiple connections give a better distri- bution and circulation of the water. The usual method of heating water for swimming pools is shown in Fig. 169. The heater, which in this case is an ordinary feed-water heater, is connected up so either live steam or exhaust steam can be used. A pump is used for circulating the water, and the connections to the pump are cross connected to the sewer, so the water from the pool can be discharged by the pump into the city sewer. Sterilization of Swimming-Pool Water. — The water in a swimming pool becomes contaminated very quickly when in use, each bather contributing some towards this state of affairs. Serious infections have been traced directly to unsanitary pools. The Detroit Board of Health took weekly samples of a pool for a period of one year. During Fig. 168 Heating Plunge with Water Heater Digitized by Microsoft® Principles and Practice of Plumbing 363 this time filtration and chemical disinfection were used. The result showed a maximum count of 216,000 colonies of bacferia per cubic centimeter — a cubic centimeter is about 15 drops — and an average count of 26,706 colonies per cubic \ Sfe fe & centimeter. All samples showed gas indicating colon bacilli. The water in a swimming pool ought to contain not more than 1,000 colonies per cubic centimeter. There is no Digitized by Microsoft® 364 Principles and Practice of Plumbing standard established as yet, however, so the practice lacks uniformity. The California State Board of Health offers the following as a standard for the bacterial purity of water in swimming pools, which will answer until a national standard is adopted : "All the water in the pool and applied to the pool shall ^SUPPLY TO POOL INLETS CIRCULATING OUTLET- Z^' DRAIN CTRCUUVTING CUTLET-- I 1 <8>i" .4_j ifcATTR sumv-^ Fig. 170 Swimming Pool Plan be continuously safe hygienically. As a tentative standard, a total bacterial count of 1,000 colonies per cubic centimeter on agar, incubated at 37.5 degrees C, and a B. Coli count of 1 per cubic centimeter, is set for the pool water in any part of the pool examined within 48 hours after sampling. "All tests are to be made in accordance with the latest SCUM GUTTER O OVERFLOV. J.J^T ~ S^ CIRCULATING OUTLET DRAIN. l-WMNEKl* ROOM Fig. 171 STvlmming Pool Section methods of the American Public Health Association." The dilution method is now generally employed to main- tain the purity of the water in a swimming pool. The dilu- tion method consists of supplying a water that is originally pure, distributing that water evenly and uniformly through- out the tank, and supplying it in sufficient quantity to insure Digitized by Microsoft® Principles and Practice of Plumbing 365 frequent changes of the water in the pool. This is done by recirculating the water through cleansing and heating appa- ratus, and back again to the pool. In Fig. 170 is shown the plan of a swimming pool, and in Fig. 171 a section through the same pool. In Fig. 172 can be seen the layout of apparatus serving the pool. Ref- erence letters refer to all three illustrations. It will be observed that the inlets are at one end of the tank, and the outlets at the other. Water is drawn from the pool and WATER SUPPLY. ®OSt= TO POOL INLETS U- tiS&BBSSSiariSSBSXSiSGAS^/lSiiiSSrasaf^S^(t{SSSX^2^Sa^)a^S^avieJHrkfa*ta r^ V \ fc -4- ■ FROM POOL DRAIN Fig. 172 Lay-out of Apparatus Serving Pool forced through the filter, A, by means of pump, B. From the filter the water flows to the heater, C, or is by-passed around the heater if the water is warm enough. From the heater it flows through a battery of two ultra violet ray sterilizers, which are generally used for the sterilizing of water in swimming pools. The filters clarify the water, the heater heats it, and the ultra violet ray apparatus steril- izes the water. The apparatus is so connected that new water from the city mains can be made pass through filter, heater and sterilizer before discharging into the pool. Digitized by Microsoft® 366 Principles and Practice of Plumbing CHAPTER XXXIII APPENDIXES Decimal Fractions of a Foot. — Measurements ex- pressed in fractions of an inch can be converted into decimal fractions of a foot by the following rule: Rule — Multiply the measurement expressed in fractions of an in^h by 1/12, and divide the numerator of the product by the denominator; the quotient will be the corresponding fraction of a foot expressed as a decimal. Example — Reduce % inch to a decimal fraction of a foot. Solution— % X 1/12 = 3/48 = .0625. Answer. For convenience in reference, Table XCIX of decimal equivalents of a foot for each 1/64 of an inch is appended. Decimal fractions of a foot can be converted to common fractions of an inch by reducing the decimal to a common fraction of lowest denomination and dividing it by 1/12. Example — Reduce .0625 of a foot to a fraction of an inch. Solution— .0625 = -^^— = 1/16, and 1/16 H- 1/12 = %. Answer. 10000 Decimal Equivalents of an Inch. — Measurements that are expressed in fractions of an inch can be converted into decimal fractions by dividing the numerator by the denominator. Example — What is the decimal equivalent of % of an inch? Solution — % = 1-^8:= .125. Answer. Fractions of an inch expressed as decimals can be con- verted to common fractions of an inch by changing the decimal to a common fraction, and thei^reducing it to its lowest terms. Decimals can be changed to common frac- tions by using the decimal for a numerator, and writing below it for denominator 1, with as many ciphers annexed as there are decimal places in the numerator. Example — ^Reduce .125 to a common fraction. 125 Solution — .125 = -— — = %. Answer. Digitized by Microsoft® Principles and Practice of Plumbing 367 M"^»Ot^00C3T-HCqC0lCCDt^0iOT-((NTtilO500003OC GOOOCOCOOOQOOOoboOoboOOOOOOOOOOOOOQOQOOOOOOOOOOOQOOOOOOOOOCOCOCO s e o 5W o 09 1 u Q OCO'£iOi(NiOOOi-i-<:Hl>OCOeOOi(NlOOOi-H-<*l>OCOCOOsC^CDai(NU300THTf< Oi-HcncDt^C30 iO"0iCiOiOlCUSiOCC)COCDCC)CDcDcDcOt>l>l>I>I>t^l>i>G000Ci0000000C0a> t- t- !> t^ t^^t>. i>i>-i:^b-i>i>^-i>i>i>r^i>i>i>t>b-t^i>t^i>i>-t>.i>t^i>i> cOOOOSO»-tCOrPiOt^OOOSi-H(NCO''^ ,, , _. . .^ c0cDC0l:^lr^t^l:^l>-I>lr^l>00Q0000d00C»000i030i0iOsa>ai0iOOOOOO CO cDcDCOcOcOcOtDcDcOCOcDCOCOCOcDcOCOCOcOCOCOCOcOcOCOI>-t^t^l>"I>- 1^ COTjdC .„,, - -- , -^ -. - G0000000000003050iOaC:iOiOiOOOOOOOOi-ti-i»-Hi-(T-ir-i,-(rH(N(N(N kOiC»0»CiO«OW3iOiO»OiOlOiOCOCDCOOCDCD?DCD<:OCOCOCOOCDCOCOcOCDCO OeocD05(MiOOOT-i-^t^OCOCDO(NiOOOT-H-^l:^OCOCDOsC0.rH--OCvDc0Ol.OC0tD0iC CO-^Ot>-OOc3l'-HNeOincDI:^050'-lW'^lOOCOOSOCMeOT:HV5t>OOOlipHC^CC COCOCOCOCOOO'rWTi5-«*TiH-<^TH'«*iO»OiOiOiOU3lO»Oi:OcDCDCO(©COCDCO(>b-l> COMCOCOCOCOCOCOMCOCCCOCOeOCOCOCCCOMCOCOMCOCvSCOCOMCOCCCOCOCO OC0005COCOC005WiOCOi-HTtl|>-OCOc005(NCOOSC-aJOr-HCO'^lOOOOOON«'*CDt>C005i--IClCOtOa)0 iniCiOiOiOOiO»OOOcOcOCOOOcDI>.b-r^t^l>-l>-l>b-OOOOOOCi000000005 h-.OCOtOCTC^iOCXJi-H'^t^OCCCOOSCQiOCiOi— iTHt^OCOcDOlC-lWSOOi-H-^t^O cDOcDi^I>t^t-t^t—l>-I^000000Q00000000S050s0i0i0i0s0iOOOOOO ;j:;;i;»H.-HT-HrHi-H,-H^.-H^rH^^r-(l-Hr-K.-H,-H.-H,-H,-Hi-H,-H,-H,-H(NCT-H'<#l>OMCD03C^iCG0i-t'^b;OC0C0a)NW3Q0i-HTff|>- CO-^SblVOOOii-HNCOiOCDr*050i-HN'OOOii-H(NCO OOOOOOOOGOCOOSaiOia)OiOSOiOOOOOOOOi-li-li-li-4T-ii-lT-l»-i(N(N(N OOOOOOOOOOOOOi-HT-(i-HT-lTHi-ti-li-HT-l>-lt-H*-(T-'i-l,-Hi-l,-l,-|,-H MCOCS(NiOC)Oi-iT:t00^^050'-lM'*u^cDO COmOWC^-^COt^OOOrHtN-^iOCDt^OiOi-iCO-^iOt^OOCsOMeOTPcDtvOOO ^o^ococDcocc^cococD^-t^l^-^>.^^-^^t^^-ooQOooooooooooclOos0500^as050^0 OCOcOoi.OC0CD05CGOO'— lC^'^>^cD000iOi-iP0-<:H»0l>-00a5*-'C^C05'^t-00Oi-'MTtHi0 I>t^t^l>OOOOCiOOOOOOOOOOOOlOiOlOSOlC50s020000000i-li-li-it-i^ OOOOOOOOOOOOOOOOOOOOC000000000000000000003050S050S050S0305030iOi ^^OC0C00iCOC0CD0il^^IO00l-l-^I^-OC0<:DC5(Nl000l-^Tt^^>O i-HCOTHiOCOOOC3SO(NCO-^CDt-*QOOii-i(NCOiOCOI>-050'-HMrH"3COOOO>ON OiOOiOlOOSOSOOOOOOOOi-Hi-lw.-Hi— lr-H.-Hl>.I>I>I>t>O0COO0GOOOO0O0O0O0O0OOCiOOOO0COOOODOOO0O0OO0OO0COCO C0C0a:iCOC0C003C:^cDt^C0Oi-l(N'^i0C01r*0sOi-tC0'^v0t>000iOC^CC-^c0b-00 OOl-^'-Hr-^w^-H^T-^c*^(^^C<^C<^(NC^C<^C^cocococococO(^OCOTJ^■<^rt^■«^■^1^■^>-r^l>•^-^-^-^^^-.i^-^-.^^^-.I>^*^-t*^*^^^-^-^>^-^-^-^-^^-l^■^-t>^^^^ OMO0SC^LCG0i-HTtOe0CD05C^iO00i-<'^r^OC0tDCsC-ococDOiCocoi:Dosc^iooOi— c-^r^o rHcro■<*^lCOOOOiOCNCOT*^cD^*0005rMMl^Ou:)':Cl^:^CDO'--^(^^'<:^|»OcDOOCsO(^1 "Tt^co■^t^■Tt^"^TH■^Ol0^ou:lw:)uol0^oocDOcD<£)^cD^>.^-^>^-l>^-^-^-QOoo X m CO CO CD (N >OC 00 Oi 0(N CV3 ■« U3 lO CD CO CO C - OCOCDOiC<^lOOO^-lTt^t^OCOCDOiC^lCOO'-HTt^^^OCOcOOlC^l:DOlC^lOOOT-^r*^ oco^-lMQl-H(N'^»ocoooc^)0'-^(^0'^lr:>^^oocnl-l(^^coTt^cD^^ooo^(N■^lC^ I>l>h-I>-OOOOGiOOOOOOOGOOOOSOS0050iOS050500cr50000T-ir-ii-it-'i-H COCOroirOCOCOCOCOfOCOCOCO«COCOCOCOCOCOCO-^'5jH'<^Tt-OCOCOOi(NiOOOr-iTHIr^OCOCDClN»nOOi-<-<^t>0 rHCO"^u:)CDoOOOC^eO'^cDt^OOOii-i(NeoiOcot--asOi-H(MTjiiocDOOO>0(N 05aic:iOsa:i050iOOOOOOOO«-HT-H»-HrH»-Hi-Hi-i(N(Nc^cO00'-H-^t-OP0CD0iC<|i0Q0T-lTjl:^OiOrHCO'^iO(>COOiONCO'^COI>GO OCOcOOSN>^COT-HT}*I>-OCOCDa)(NiOOOrH'CXDO'-<(N'^»/S CqC^C^lN«COcrOCOCv3COCOCOTH"<:H'^'^'^*^-=**TtHi^iOiOiOiOU5u^CDcOCDCDcO t^OC0C00:l^lLra00wT*l|>oc0c00:)C^l0G0■<-HT^^t>OC0C00l£^»0CCl-l'<*^^-O ^CO'-^>-^^r'-^^^-.o'^oo oooooooooooooooooooooooooooooooo CO N 2 I I t IM ^ (M Digitized by Microsoft® Principles and Practice of Plumbing 369 Decimal equivalents of fractions of an inch can be found in Table C. TABLE C. Decimal Equivalents of Fractions of an Inch 8ths 1/8 = .125. 1/4 = .250 3/8 = .375 1/2 = .500 5/8 = .625 3/4 = .750 7/8 = .875 leths 1/16=. 0625 3/16= . 1875 5/16=. 3125 7/16=. 4375 9/16=. 5625 11/16=. 6875 13/16=. 8125 15/16=. 9375 32ds 1/32=. 03125 3/32=. 09375 5/32=. 15625 7/32=. 21875 9/32=. 28125 11/32=. 34375 13/32=. 40625 15/32=. 46875 17/32=. 19/32=, 21/32=. 23/32=, 25/32= 27/32=, 29/32=, 31/32=, 53125 59375 65625 71875 78125 84375 90625 96875 64ths 1/64=. 015625 3/64=. 046875 5/64=. 078125 7/64=. 109375 9/61= 11/64= 13/64= 15/64^ 17/^4= 19/64= 21/64= 23/64= 25/64= 27/64b= 29/64= 31/64= 33/64= 35/64= 140625 171875 203125 234375 265625 296875 328125 359375 390625 421875 453125 484375 515625 546875 37/64^ 39/64= 41/64= 43/64= 34/64= 47/64= 49/64= 51/64= 53/64= 55/64= 57/64= 59/64= 61/64= 63/64= ,578125 ,609375 ,640625 ,671875 703125 734375 ,765625 ,796875 ,828125 859375 890625 ,921875 ,953125 984375 Decimals of a Square Foot. — Measurements taken in square inches can be converted into decimals of a square foot by dividing the number of square inches by 144, which is the number of square inches contained in a square foot. Example — Express 20 square inches as a decimal of a square foot. 20 Solution— 20 square inches^-- — =20-H 144 = .138. Answer. Square inches expressed as decimals of a square foot can be found in Table CI. To reduce decimals of a square foot to square inches, multiply the decimal by 144. Example — Reduce .1388 of a foot to square inches. Solution — .1388 X 144 = 20 square inches nearly. Answer. Aeea of a Circle. — To find the area of a circle, square the diameter and multiply by .7854. Squaring the diameter means multiplying the length of the diameter by itself. Example — What is the area of a circle having a diameter of 20 feet? Solution— 20 X 20 X -7854 = 314.16 square feet. Answer. Diameter of a Circle. — When the area of a circle is known, the diameter can be found by dividing the area by ,7854 and extracting the square root, Digitized by Microsoft® 370 Principles and Practice of Plumbing Example — What is the diameter of a circle having an area of 314.16 square feet? Solution— 314.16 -h .7854 = 400 and tf 400 = 20 feet. Answer. TABLE CI. Square Inches in Decimals of a Square Foot Square Square Square Square Square Square Square Square Inch Foot Inch Foot Inch Foot Inch Foot 1 .00694 15 .10416 29 .20138 43 .29861 2 .01388 16 .11111 30 .20833 44 .30555 3 .02083 17 . 11805 31 .21527 45 .31249 ,4 .02'/'/'/ 18 . 12500 32 .22222 46 .31944 5 .03472 19 . 13194 33 .22916 47 .32638 6 .04166 20 . 13888 34 .23611 48 .33333 7 .04861 21 .14583 35 .24305 49 .34027 8 .05555 22 . 15277 36 .25000 50 .34722 9 .06250 23 . 15972 37 .25694 61 .35416 10 .06944 24 . 16666 38 .26388 52 .36111 11 .07638 25 . 17361 • 39 .27083 53 .36805 12 .08333 26 . 18055 40 .27777 54 .37500 13 .09027 27 .18750 41 .28472 55 .38194 14 .09722 28 . 19444 42 .29166 56 .38888 57 .39583 79 . 54861 101 .70138 123 .85416 58 .40277 80 .55555 102 .70833 124 .86111 59 .40972 81 .56249 103 .71527 125 .86805 60 .41666 82 .56944 104 .72222 126 . 87500 61 .42361 83 .57638 105 .72916 127 .88194 62 .43055 84 .58333 106 .73611 128 .88888 63 . .43750 85 .59027 107 .74305 129 . 89583 64 .44444 86 .59722 108 .75000 130 .90277 65 .'45138 87 .60416 109 .75691 131 .90972 66 .45833 88 .61111 110 .76388 132 .91666 67 .46527 89 .61805 111 .77083 133 .92361 68 .47222 90 .62500 112 .77777 134 .93055 69 .47916 91 . 63194 113 .78472 135 .93750 70 .48611 92 . 63888 114 .79166 136 .94444 71 .49305 93 . 64583 115 .79861 137 .95138 72 .50000 94 .65277 116 .80555 138 .95833 73 .50694 95 . 65972 117 .81249 139 .96527 74 .51388 96 .66666 118 .81944 140 .97222 75 .52083 97 .67361 119 .82638 141 .97916 76 .52777 98 . 68055 120 .83333 142 .98611 77 .53472 99 .68750 121 .84027 143 ,99305 78 .54166 100 .69444 122 .84722 144 1.00000 Life of Cast Iron Pipes The question often arises, how long will cast iron pipe last when buried in the earth. This question cannot be Digitized by Microsoft® Principles and Practice of Plumbing 371 answered definitely in any case, for the life of a cast iron pipe will depend upon the chemical composition of the earth and water it is in contact with, the chemical constituents of the fluid passing through, and whether or not the pipe is covered with a protective coating. The following data, however, will serve as a guide in forming a judgment. The only data from observations at hand are found in reports from St. John, N. B., and Los Angeles, Cal. The superintendent of the water works at the former place re- ported in 1892 several observations. In one case a 4-inch main, in use about 33 years in marsh mud, had failed by softening of the outside, and the break took place at some air cells in the body of the pipe. A 6-inch pipe 52 years old in soft, slaty rock, failed from softening. A 24-inch pipe laid in well drained, gravelly brick clay, 36 years old, failed from inherent de- fects in the pipe, the outside of the pipe being sound and the inside having a coat less than 1/16 inch thick. None of these pipes were protected by coatings. The conclusion regarding the 24-inch pipe in well drained gravelly clay was that, aside from the defects in manufacture, its life would have been practically indefinitely long. The City Engineer of Los Angeles, Cal., reported the condition of the water works in 1897. The pipe was un- covered in 318 places. Cast iron pipe 28 years old was found in a perfect state of preservation. In sand or loam the bare pipe metal did not rust. In hard adobe soil there was some rust, but the pipe was practically uninjured. In all cases the original asphalt coating had practically disap- peared. A later report of a board of engineers, estimated the depreciation of the water pipe in the city in the better soils at 1.25 per cent, per annum, indicating a life of 80 years, and in the poorer soils at 2 per cent, per annum, indi- cating a life of 50 years. The effect of the soil upon the outside of the pipe and of tuberculation upon the inside are both allowed for in these estimates. In case there is opportunity for electrolysis from street railway or other electric leakage, the life of pipe is very Digitized by Microsoft® 372 Principles and Practice of Plumbing greatly shortened. Some chemical conditions of soil which will shorten the life of pipe will doubtless also be met with. Length of Life of Wrought Iron Gas Pipe Like with cast iron pipe buried in the ground, any statement about wrought pipe that would be correct in one locality inight be entirely wrong in another, its life depend- ing largely upon the chemical composition of the land through which it runs. There are cases where pipes which had been in but 10 years, upon examination were found to be badly decomposed, while in another locality which pipe that had been under ground 25 years when uncovered show- ed but little signs of decay. This refers to the outside surface only. Cases are rare, however, when pipe would be so affected in 10 years as to require replacing. While chemical action figures largely in considering this question it is not the only thing to take into account when consider- ing the life of gas pipe. Electrolysis is liable to be more destructive in its attacks than the ordinary chemicals of the earth. It will be seen, therefore, that it is quite impossible to give any definite data on the subject, but under ordinary circumstances cutting out the possibilities of electrolysis and especially corrosive soil, 25 years would be about as long a life as the average underground gas pipe would last, so far as outside deterioration is concerned. When the inner surface is considered, however, an entirely different problem is presented. There we have the quality of the gas to consider. For instance, gas pipes which for years gave perfect satisfaction, while coal gas was being distributed, became entirely useless from the effects of the gas, when adulterated gas was forced through the mains, naphthalene and rust accumulating to such an extent as to stop the flow of gas entirely. As a rule gas pipes suffer more from the inside than the outside, particularly in the case of small pipes where the impurities and condensation have a better chance to work on the entire surface, making small pipes shorter- lived than the larger ones. And while a good sized pipe might be in fairly good Digitized by Microsoft® Principles and Practice of Plumbing 373 condition at the age of 25, the smaller sized might be filled with rust and condensation and be condemned at 15. Under favorable conditions, good gas, etc., there is no reason why pipe of sufficient sizes should not be good for 25 years at least, conducting either gas or water. The Sherardizing Process The process of sherardizing metals is becoming so ex- tensively used in the manufacture of plumbing materials, that a better knowledge of the process should be had by all engaged in the business. In the course of some extensive experiments, writes Thomas Liggett in The Foundry, for the purpose of improv- ing case-hardening methods, early in the twentieth century, Dr. Sherard Copew-Cowles sprinkled some zinc dust on a piece of steel and subjected the whole to the ordinary case- hardening process and at a temperature less than the melt- ing point of zinc — less than 788 degrees Fahrenheit. When the material cooled, he found that the steel was coated with a thin layer of zinc. After thorough and exhaustive tests it was found that this coating gave the underlying metal better protection than that obtained by the well known hot process, or galvanizing as this is known. The essential apparatus necessary in a sherardizing plant is an oven large enough to receive the retorts or drums which contain the material to be treated. The larg- est retorts in use today are 26 inches in diameter and 23 feet long, designed for merchant pipe. The retorts are loaded with the material to be treated and zinc dust or dross, placed in the oven and subjected to the heat from any of the common fuels, providing that an even temperature may be maintained. The retorts are left in the oven for a short period at a constant temperature and then removed. When they can be handled, they are opened and the material and unused dust are dumped on a screen or grating. The dust falls through and is ready to be used again. The material is finished and found to be covered with a continuous, uni- form coating of zinc iron alloy, with a very thin coating of pietallic zinc on the surface, Digitized by Microsoft® 374 Principles and Practice of Plumbing No matter how irregular the shape of the material, it has a uniform coating and everything is reproduced. An inconsiderable amount of superficial material is added by the sherardizing process. The zinc dust which is used in the process is -a secondary product from a zinc smelter and is recovered in the flues. The dust is com- posed of from 85 to 92 per cent, metallic zinc, about 7 per cent, zinc oxide and some other impurities which are not in sufficient quantities to work any injury. Zinc dross also can be used instead of dust and it has its advantages. It is the material which settles to the bottom of a galvanizing kettle. After treating it, no difficulty is found in pulveriz- ing it for use. While there have been several theories ad- vanced as to the action which takes place in the retorts or drums during the process, the following facts alone are known : If metallic zinc content in the dust is kept constant there is on the same class of materials equal weights of coating, under the same temperature and time of treatment. Zinc does not begin to deposit until the material has reached the temperature at which magnetic oxide of iron appears. Iron which oxidizes with, difficulty, sherardizes with difficulty. The continuity of the zinc dust coating, when properly applied, is equal to and in the majority of cases superior to the hot galvanized coating. While, it is true, under the microscope the zinc iron alloy shows cracks or fissures, these are of such minute dimensions that nothing can get through to the underlying metal. The adherence of this alloy is very tenacious. The durability of the alloy coating is great, although it is a little more brittle than pure zinc and has a slight tendency to flake if bent through a sharp angle. The metal which is exposed after the flaking is still resistent to corrosion, which shows that the underlying metal is not exposed. The resistance of the alloy to corrosive agencies is much greater than with the zinc coating. In testing sherardized material the method most frequently used is the Preece or copper Digitized by Microsoft® Principles and Practice of Plumbing 375 sulphate method. This consists of immersing a piece of galvanized material in a standard copper sulphate solution for one minute then washing in clear water and drying with cotton waste. This is repeated four times, and if there are no bright metallic copper deposits, the material is accepted. The standard solution is one whose specific gravity at 65 degrees Fahrenheit is 1.186. It is prepared by dissolving copper sulphate in water, to which an excess of cupric oxide has been added. This solution is then filtered and the spe- cific gravity made 1.186 at 65 degrees Fahrenheit. The trouble of testing sherardized material by this method is that if the material is wiped with waste a burnishing action takes place. The reasons for this are that the sherardized coating being an alloy, the copper is deposited more slowly and is more adherent than that which deposits on hot galva- nized material; as the sherardized surface is rough it af- fords a foothold for this copper and the waste rubbing the top burnishes the copper so that instead of cleaning the surface as the specifications intend, the deposit is rubbed onto the object. With further dipping, the copper deposit thickens, and those not thoroughly familiar with this action will decide that the coating has failed. To overcome this, it is always best to use a stiff bristle brush and scrub lightly instead of using waste. The Cost of Digging The plumber has so much digging and refilling of trenches for his pipes, that the following data as to costs will be convenient. In laying sewers and water-mains, men will excavate and throw on the bank 10 cu. yds. of sand or easy earth and from that down to 6 cu. yds. of very hard picking earth in a day of eight hours. In back-filling with shovels, any good workman should average from 12 to 16 cu. yds. in eight hours. For shallow work, that is trenches not more than five feet deep, the above output should be increased about 50 per cent, for excavation but the figures for backfilling maintained. If a laborer is paid $1.50 for 8 hours' work and can put out 8 cu. yds. of earth, the cost will be a trifle under 19 cents for digging. The cost of Digitized by Microsoft® 376 Principles and Practice of Plumbing backfilling will be about 12 cents, thus making the total cost per yard only 31 cents. It is seldom that stone which must be drilled and blasted, will cost more than $2.00 per cu. yd. Ice Freezing of water is the cause of much trouble in plumbing systems. Burst pipes and vessels, the most com- mon damage, is caused by the expansion of water when it turns from the fluid to the solid state. When it freezes, water increases in volume 10 per cent., so that ten volumes of water produce 11 volumes of ice. Fresh water, under ordinary circumstances, when it reaches the temperature of 32 degrees Fahrenheit, passes to the solid state, or crystal- izes into ice. Water in freezing always expands. If it be so confined that expansion is impossible, "it remains liquid even at tem- peratures far below the freezing point ; but the instant the pressure is removed, the water freezes into solid ice. As there is a constant effort on the part of water exposed to freezing temperatures to form ice, and as a very consider- able pressure is needed to counterbalance its expansive force, the lower the temperature the greater the pressure becomes. At a temperature of 30 degrees Fahrenheit the pressure amounts to 146 atmospheres, or the weight of a column of ice' one mile high ; or 138 tons per square foot. Consequently, when water freezes at a lower temperature, the pressure on the walls of its enclosing vessel exceeds 138 tons per square foot. Bomb-shells and cannon filled with water and hermetically sealed, have been burst in freezing weather by the expansion of the freezing water within them. When water is under pressure, for every atmos- phere of pressure, that is, for every 14.7 pounds to the square inch, the freezing point is lowered by .0075 degree Centigrade. Multiple Shrinkage of Floor Beams. — In buildings of wooden floor construction there is more to consider than the mere shrinkage of one depth of floor joist. There is the multiple shrinkage of the several tiers of joists. Buildings Digitized by Microsoft® Principles and Practice of Plumbing 377 over five stories in height seldom have wooden floor beams, although up to that height they are the rule rather than the exception. If we take as an example, then, the multiple shrinkage in a three-story building, it will do to explain the case. In Fig. 173 is shown the framework of an ordinary building when properly put together. This illustration shows a row of brick piers in the centre of the building supporting a 10 x 12 girder on which rests the centre bear- ing partition to carry the floor beams for the upper floors. ■Shrinkage he^e '/e'nc/i ThlRD rUQDO .LF /Z"Jo'sfj ■^Double P/afe Second Fuod^^ /B''J'ofsfs M \£)oui>/e Pfa/e ^fbsi//onofSeam6ef<»v.sim!k!^e ^ /2' Jaf's/s ^ pbsif/an a/" Beam aff^er J/innkOfe m ^ /e'xiz'- 3hr/f7/fi7^e ^^^ hen '&moh ^^ Fig. 173 Framework of an Ordinary Building When Properly Put Together It will be observed that each tier of beams rests on a plate made of two 2x4 and from this plate the studdings are erected for the next tier of beams.- If the total shrinkage for the three floors be now computed it will be seen that the 10 X 12 girder has shrunk approximately 1/2 inch, and the two plates on which the second and third floor beams rest, Digitized by Microsoft® 378 Principles and Practice of Plumbing each being 4 inches deep, shrink approximately 1/6 inch each. The total shrinkage for the third floor therefore would be 1/^ plus 1/6 plus 1/6, equals 5/6 of an inch. The dotted line shows the original position of the joists, and the solid lines the position after shrinkage has taken place. It might be well to add that carpenters are aware of this shrinkage of timbers and in building make the floors higher in the centre than at the walls to allow for the shrinkage so the floors will be about level when the building has dried out. THfRD Floor 16" Will shrink about -^mch /l-'li^rS ^^Doub/e p/afe OccoND Floor ■S/na/e 'O/// /&" Joist /e"hf>// s/irm/r aiouf % /ncA ^Doab/e p/a/a First Floor 1 I r ie"yo/st ty/a"x/a~Seam £6 M//sMn/r aixtut ///k/j Fig. 174 Framework of a Commonly Constructed Building But buildings are not always erected as they should be. In the illustration, Fig. 174, is shown how they commonly are constructed. This method of framing saves a foot in length of every studding at each floor, and for this reason is more often followed than the better method. The difference to the plumber and fitter, however, will be readily seen. Instead of all floors resting on a partition supported by a girder so there would be no shrinkage to Digitized by Microsoft® Principles and Practice of' Ptumbing 379 take care of but that of the girder and two double plates (wood does not shrink lengthwise perceptibly) in the pres- ent method the bearing partitions for each floor rests on a single plate supported by the floor joists below; the result is, the upper floors are affected by the shrinkage of the floor joists on every floor below them. In the present instance, the joist, sill and girder of the first floor are 26 inches deep and will shrink all told over 1 inch. The double plate, joist and sill of the second floor being about 18 inches deep will shrink approximately % inch; while the double plates and joists of the third floors, being 16 inches deep, will shrink about % inch. The total lowering of the floor line of the third floor then will be 1 plus % plus %, equals 2% inches, as against less than one inch in the former method of construction. It will be seen, therefore, that the plumbers and fltters in lay- ing out their work must take into consideration not only the shrinkage of beams and timbers and their combined shrink- ages, but likewise the method of construction and make due allowances in the connection to radiators, and provide flex- ible and collapsible connections for water closets. Water Pipe Sizes in Various American Cities Sir : The writer has recently compiled statistics of the amount of the several sizes of water pipe in use in the fol- lowing cities : . Cambridge, Mass. Lowell, Mass. Fall River, Mass. Brockton, Mass. Attleboro, Mass. Hartford, Conn. Richmond, Va. Troy, N. Y. Washington, D. C. Holyoke, Mass. Concord, N. H. Brookline, Mass. Providence, R. I. Corning, N. Y. Boston, Mass. New Haven, Conn. Wilmington, Del. Springfield, Mass. Reading, Pa. Binghamton, N. Y. Albany, N. Y. Worcester, Mass. Rochester, N. Y. Waterbury, Conn. New Bedford, Mass. As these 25 cities may perhaps be considered as repre- senting the average of a greater number, the following result is given, as being of possible interest to your readers : Digitized by Microsoft® 380 Principles and Practice of Plumbing Size. Percentage. Size. Percentage. 3 in. .77 18 in. .03 4 in. 8.93 20 in. 2.81 6 in. 44.98 24 in. 2.54 8 in. 14.44 30 in. 1.99 10 in. 4.00 36 in. 1.17 12 in. 12.64 40 in. .30 14 in. .42 42 in. .20 16 in. 4.38 48 in. .40 W. B. Franklin, Press of Lyon & Armor Phliaaelphla, Pa. Digitized by Microsoft® Principles and Practice of Plumbing 381 INDEX A Page. Absorption and Radiation of Heat 245 Acid and Alkali, Fibre Conduit for 16 Acid and Alkali Wastes, Piping for 12 Acids, Resistance of Metals and Alloys to 15 Action of Wind on Windmills 319 Air Chambers 199 Air Chambers 162 Air Leakage, Effect of on a Siphon. .■ 48 Air Locks in Plumbing 165 Alkali and Acid, Fibre Conduit for 16 Alkalia and Acid Wastes, Piping for 12 Alloys and Metals, Resistance of to Acids 15 Apparatus, Deactivating 240 Apparatus, De-Aerating 241 Apparatus, Deoxidizing • 240 Apparatus, Water Heating 245 Appliances, Safety ". . 298 Area and Yard Drains 45 Area of a Circle 369- Automatic Water Heaters 277 B Back-Pressure on Traps 91 Back-Venting Traps 95 Boiler Connections 294 Blow-Ofif Tanks 99 Boilers, Copper 288 Boilers, Range 289 Boiling Point of Water 248 Booster Heaters 275 Brass Pipe 175 Buildings, Settlement and Shrinkage of 80 c Capacity of Drains Running Full 32 Capacity of Pipes, Discharging 146 Capacity of Pumps 202 Capacity of Sewer Pipes 37 Capacity of Waterbacks and Coils 255 Capacity of Water Heaters 257 Cast-iron Pipe, Life of , 370 (Circle, Area of si. ,..,,.,;,.,,,,.,,,,: -^ ,,::■■■ ^ ,., 369 Digitized by Microsoft® 382 Principles and Practice of Plumbing Page. Circle, Diameter of a ■ . 369 Circulation of Water 252 Circulation Pipes 305 Classification of Water 116 Cleanout Ferrules 22 Closet Floor Flanges 346 Closets, Reverse-Trap 345 Closets, Siphon-Aotion 344 Closets, Siphon- Jet 345 Coagulant 220 Cocks and Valves 178 Coils and Waterbacks, Capacity of ^ . . . 255 Coils, Cooling 314 Coils, Steam 262 Commingler 268 Connection, Service 187 Connections to House Drain 21 Connection to Street Sewer 19 Consumption of Water, Per Capita 35 Continuous Vent or Loop System 60 Contracted Vein, The 134 Contraction and Expansion of Leaders 44 Cooling Coils 314 Cooling Tanks 312 Copper Boilers 288 Corrosion of Lead Pipe 169 Cost of Digging 375 Covering for Tanks 310 Coverings, Pipe ■. 308 D Deactivating Apparatus 240 De-Aerating Apparatus 241 Decimal Equivalents of an Inch 366 Decimal Equivalents of Fractions of an Inch 369 Decimal Fractions of a Foot 366 Decimals of a Square Foot 369 Deoxidizing Apparatus 240 Diameter of a Circle 369 Digging, Cost of , 375 Discharging Capacity of Pipes 146 Distance Fixtures Can Be from Stack , 64 Distance of Back-Vent from Trap 94 Draft Regulators 304 Drainage, Sub-Soil 109 Drainage System, Example of a , , , , . ,, 1 Digitized by Microsoft® Principles and Practice of Plumbing 383 Page. Drainage System, Proportioning the 28 Drains Running Full, Capacity of : 32 Drains, Velocity of Flow in.' 28 Drive-Pipe for Rams 334 Duriron 13 E Effect of Water Upon Metals 120 Efficiency of Filters. 224 Equation of Pipes 189 Equivalents of an Inch, Decimal 366 Evaporation from Traps 91 Example of a Drainage System . . 1 Expansion and Contraction of Leaders 44 Expansion of Pipe 307 Expansion of Soil and Waste Stacks 79 Expansion of Water 248 F Fibre Conduit for Acid and Alkali 16 Filters, Efficiency of , 224 Filtration 219 Filtration Controllers 222 Fire Hose 217 Fire Lines 212 ' Fire Streams, Range of 213 Fires, Temperature of 248 Fixtures, Distance Can Be from Stack 54 Fixtures for Schools, Number of Toilet 344 Fixtures, Plumbing 340 Fixtures Required, Number of 342 Flanges, Closet Floor 346 Flashings, Roof , 83 Floor Beams, Shrinkage of 376 Floor Drains 26 Floor Flanges, Closet 346 Flow in Drairts, Velocity of 28 Flow of Water at Plumbing Fixtures 194 Flow of Water Through Pipes 134 Flow, Velocity of 141 Flush Tanks 348 Flush Valves 349 Force Pumps 198 Fractions of a Foot, Decimal 366 Friction in Pipes 134 Digitized by Microsoft® 384 Principles and Practice of Plumbing Pace. Fresh-Air Inlet 39 Full- Weight and Merchant Pipe 175 G Garbage Burning Water Heaters , 260 Gas, Heat Units in 276 Gas, Kinds of 275 Gasoline and Oil Separators 46 Grease Traps 91 H Hardness of Water 118 Head, Loss of 142 Heat, Absorption and Radiation of 245 Heat, Measurement of 246 Heat, Properties of 245 Heat, Transfer of 245 Heat, Transmission of . . 247 Heat Units in Gas 276 Heaters, Automatic Water 277 Heaters, Booster 275 Heaters, Multi-Coil Storage 279 Heaters, Water 256 Heating Apparatus, Water 245 Heating Water by Steam in Contact 265 Heating Water for Swimming Pools 361 Heating Water with Gas 275 High-Silica Cast-iron Pipe 13 Horsepower of Pumps ; 201 Hose, Fire 217 Hose Reels 218 Hospital Lavatory 354 Hospital Slop Sinks 354 Hot Water, Properties of 248 Hot Water Supply i 245 Hot Water, Tanks for Storing 288 House Drain 20 House Drains, Size of 29 House Drains, Supports for 24 House Sewers, Iron Pipe 16 House Sewer, The 7 Hydraulic Gradient, The 129 Hydraulic Pressure, Laws of 129 Hydraulic Rams 331 Hydrodynamics 129 Hydrostatics 129 Digitized by Microsoft® Principles and Practice of Plumbing 385 I Page. ^'^^ 376 Ice-Water Supply 312 Incrustation of Water Heaters 261 Iron Pipe House Sewers 16 J Joints, Lead Calked 18 Joints, Rust 18 Joints, Tile Pipe H L Lavatories, Roughing-In for 68 Law of Pressure, Pascal's 131 Laws of Hydraulic Pressure 129 Laying Tile Sewer, Methods of 8 Leaders, Expansion and Contraction of 44 Lead-Calked Joints 18 Lead Pipe, Corrosion of 169 Lead Pipe, Strength of 169 Leaders, Size of 43 Leveling Tile Pipe 9 Life of Cast-Iron Pipe 370' Life of Wrought-Iron Pipe 372 Lift of a Pump 196 Lift of Pumps, Suction 198 Loop or Continuous Vent System , 60 Loss of Head 142 Loss of Head in Meters 150 Loss of Seal 88 Laundry Fixtures and Connections 343 M JIain-Drain Trap 25 Materials for House Drain 20 Materials for Stacks 85 Measurement of Heat 246 Measurement of Temperatiure 247 Measurement of Water 147 Mechanical Discharge Systems 104 Merchant and Full- Weight Pipe 175 Metals and Alloys, Resistance of to Acids 15 Meters, Loss of Head in 150- Meters, Velocity 147 HMeters, Volume 148 Meter Rates, Water 150 Digitized by Microsoft® 386 Principles and Practice of Plumbing ' Pace. Meter, Venturi 147 Mixing Waters of Different Temperatures 253 Mud Drum 289 Multi-Coil Storage Heaters , 278 N Noiseless Water Heaters 265 JVon-Siphon Traps 90 Number of Fixtures Required 342 Number of Toilet Fixtures for Schools 344 ■Oil Separators 46 One Pipe System of Plumbing 58 ■Overheated Water 302 P Pascal's Law of Pressure 131 Performance of House Pumps 202 Permutit Process, The 230 Pipe, Brass 175 Pipe Coverings 308 Pipe, Expansion of 307 Pipe, Leveling Tile , 9 Pipe, Life of Cast-iron 370 Pipe, Life of Wrought-Iron 372 Pipe, Merchant and Full-Weight 175 Pipe Joints, Tile 11 Pipes, Circulation 305 Pipes, Discharging Capacity of 146 Pipes, Equation of 189 Pipes, Friction in 134 Pipes, Sizes of Water 192 Pipes, Water Supply 168 Pipes, Wrought Iron and Steel. ., 172 Piping for Alkali and Acid Wastes 12 Plumbing Fixtures 340 Plumbing Fixtures, Flow of Water at 194 Plumbing, One Pipe System of 58 Plumbing System, Requirements of a 6 Plumbing, Two-Pipe System of 56 Pneumatic Water Supply 338 Pools, Swimming 358 Pressure, Pascal's Law of 131 Pressure, Laws of Hydraulic 129 Digitized by Microsoft® Principles and Practice of Plumbing 387 I'age. Pressure Regulators 183 Properties of Heat 245 Properties of Hot Water 248 Properties of Saturated Steam 271 Properties of Water 113 Proportioning the Drainage System 28 Pump, Lift of a , 196 Pumps and Pumping 196 Pumps, Capacity of 202 Pumps, Force 198 Pumps, Horsepower of 201 Pumps, Performance of House 202 Pumps, Slip of 198 Pumps, Suction Lift of 198 Pumps, Suction or Lift 196 Pumps, Steam 200 R Radiation and Absorption of Heat 245 Rain and Shower Baths 355 Rain Leaders 41 Rainfall, Intensity of 30 Rams, Drive-Pipe for 334 Rams, Hydraulic 331 Range Boilers 289 Range of Fire Streams 213, Refrigerator Wastes 101 Regulators, Draft 304. Regulators, Pressure 183 Regulators, Steam Coil 304 . Reverse-Trap Closets 345 Roof Connections 41 Roof Flashings 83 Roughing-In for Bathrooms on Two Floors 66 Roughing-In for Lavatories 68 Roughing-In for Single Bathrooms 63 Roughing-In Tall Buildings 69 Rust Joints / 18 Rust Prevention 238 s Safety Appliances 298 Saturated Steam, Properties of 271 School Sinks and Latrine Troughs 350 Schools, Number of Toilet Fixtures for 344 , Digitized by Microsoft® 388 Principles and Practice of Plumbing Pace. Seal, Loss of , 88 Service Connection 187 Sewer, Connection to Street 19 Sewer Pipes, Capacity of 37 Sewer, Methods of Laying Tile 8 Sewer Pipe, Dimensions of 8 Sewers, Iron Pipe House 16 Settlement and Shrinkage of Buildings 80 Soap Required to Soften Water 227 Softening of Water 226 Soil, Waste and Vent Systems 56 Solvent Power of Water 119 Sherardizing Process, The 373 Shower and Rain Baths 355 Shrinkage and Settlement of Buildings 80 Shrinkage of Floor Beams 376 Siamese Twin Connections 217 Siphonage, Application of to Fixture Trap 50 Siphon-Action Closets 354 Siphon- Jet Closets 345 Siphon Traps 87 Siphons and Siphonage 47 Siphons, Application of to Closets 53 Siphons for Equalizing Water Levels 49 Size of Fresh-Air Inlet 40 Size of House Drains '. 29 Size of Leaders 43 Size of Standpipes 212 Size of Water Pipes 192 Size of Soil and Vent Stacks 72 Slip of Pumps 198 Slop Sinks 353 Smoke Flues 257 Soil and Vent Stacks, Size of 72 Soil and Waste Stacks, Expansion of 79 Square Foot, Decimals of a 369 Stacks Above Roof, Outlets to 83 Stacks and Branches 56 Stacks, Materials for 85 Stacks, Supports for 85 Standpipes, Size of , 212 Steam Coil Regulators 304 Steam Coils ■ 262 Steam, Properties of Saturated , 271 Steam Pumps 200 Steam Required to Heat Water 270 Digitized by Microsoft® Principles and Practice of Plumbing 389 Pace. Steel and Wrought Iron Pipes 172 Sterilizing Swimming Pool Water , 362 Sterilizing with Ultra Violet Rays 234 Street Sewer, Connection to 19 Strength of Lead Pipe 169 Sub-Sewer Systems ^ 104 Sub-Soil Drainage 109 Suburban Places, Water Supply for 318 Suction Lift of Pumps 198 Suction or Lift Pumps 196 Supply, Ice-Water 312 Supply, Hot Water 245 Supply Pipes, Water 168 Supports for House Drains 24 Supports for Stacks 85 Swimming Pools 358 Swimming Pools, Heating Water for 361 Swimming Pool Water, Sterilizing 362 System of Plumbing, One-Pipe 58 System of Plumbing, Two-Pipe - 56 T Tall Buildings, Roughing-In 69 Tanks, Blow-Off 99 Tanks, Cooling 312 Tanks, Covering for 310 Tanks, Flush 348 Tanks for Storing Hot Water 288 Temperature, Measurement of ; 247 Temperature of Fires ■ 248 Tide-Water Trap 25 Tile Pipe Joints H Tile Pipe, Leveling 9 Tile Sewer Pipe, Where It May Be Used 12 Transfer of Heat 245 Transmission of Heat 247 Traps and Trapping 87 Traps, Back-Pressure on 91 Traps, Back-Venting 95 Traps, Grease 91 Traps, Distance of Back-Vent from 94 Traps, Evaporation from • 91 Traps, Main Drain 25 Traps, Non-Siphon 90 Traps, Siphon 87 Digitized by Microsoft® 390 Principles and Practice of Plumbing Page. Traps, Tide- Water ^ 25 Trapping of Leaders 41 Two-Pipe System of Plumbing 56 u Urinals 352 Ultra Violet Rays, Sterilizing with 234 V Valves and Cocks 178 Valves, Flush i 349 Velocity of Flow 141 Velocity of Flow in Drains 28 Velocity Meters 147 Velocity of Wind 319 Vent and Soil Stacks, Size of , 72 Vent System, Loop or Continuous Vent 60 Ventilation of Closet Compartments , 351 Venturi Meter 147 Volume Meters 148 w Waste of Water 152 Wastes, Refrigerator 101 Waterbacks 254 Waterbacks and Coils, Capacity of 255 Water at Plumbing Fixtures, Flow of 194 Water, Boiling Point of 248 Water, Circulation of 252 Water, Classification of , 116 Water Closets 341 Water Cooler for Outdoor Fountain , 315 Water-Cooling Refrigerating Machines 315 Water, Effect of Upon Metals 120 Water, Expansion of 248 Water, Flow of Through Pipes 134 Water Hammer 156 Water, Hardness of 118 Water Heaters 256 Water Heaters, Capacity of 257 Water Heaters, Garbage Burning 260 Water Heaters, Automatic 277 Water Heating Apparatus 245 Waler Heating Data : 282 Water, Heating with Gas 275 Digitized by Microsoft® Principles and Practice of Plumbing 391 Page. Water Heaters, Incrustation of 261 Water Heaters, Noiseless 265 Water, Measurement of 147 Water Meter Rates 150 Water, Overheated 302 Water, Per Capita Consumption of 35 Water Pipe Sizes in American Cities 379 Water Pipes, Sizes of 192 Water, Properties of 113 Water Required for Various Purposes 193 Water, Soap Required to Soften 227 Water Softening Apparatus 228 Water, Softening of 226 Water, Solvent Power of 119 Water, Steam Required to Heat 270 Water Supply for Suburban Places 318 Water Supply, Hot 245 Water Supply Pipes 168 Water Supply, Pneumatic 388 Water, Waste of 152 Water, Tanks for Storing Hot ' 288 Waters of Different Temperatures, Mixing 253 Windmills 318 Windmills, Action of Wind on 319 Wind, Velocity of 319 Wrought Iron and Steel Pipes 172 Wrougbt-Iron Pipe, Life of 372 Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® laaiigwii