^^■'i'^JU^ r r; -i»w_-. . 'V-iire* MAXIMS AKD INSTRUCTIONS FOR THE BOILER ROOM This Work is Fraternally inscribed to W, R, Hawkins, R. K Hawkins and F, P. Hawkins, Maxims and Instructions FOR The Boiler Room. USEFUL TO Engineers, Firemen & Mechanics, RELATING TO STEAM GENERATORS, PUMPS APPLIANCES, STEAM HEATING, PRAC- TICAL PLUMBING, ETC. By N. HAWKINS, M. E., Honorary ]V£ember National Association of Stationary Engineers. Editorial Writer, Author of Hand Book of Calculations FOR Engineers and Firemen, Etc., Etc. Comprising Instructions and Suggestions on the Construc- tion, Setting, Controi, and Management oe Various Forms of Steam Boilers; on the Theory and Prac- TiCAi, Operation of the Steam Pump; Steam Heating ; Practical Plumbing ; also Rules for the Safety Valve, Strength of Boilers, Capac- ity OF Pumps, Etc. Xt^EO. AUDEIv S. CO., F»ub>Hst»ers, 63 FIFTH AVE.. Cor. 13TH St., New York. 18345 TWO COPIES RECEIVEO- <^V' Copyrighted by Thko. Audki. & Co. Cr.d COPV, 10S3. PREFACE. The chief apology for the preparation and issue of these Maxims and Instructions, for the use of Steam, users, Engineers and Firemen, is the more than hind reception of Calculations. But there are other reasons. There is the wholesome desire to henefit the class, with whom, in one way and another, the author has heen associated nearly two score years. The plan followed in this worh will he the same as that so generally approved in Calculations ; the com- pleted volume will he a worh of reference and instruct tion upon those worhs set forth in the title page. As a worh of reference the worh will he especially helpful through comhined Index and Definition Tables to he in- serted at the close of the hooh. By the use of these the meaning of every machine, material and performance of the hoiler room can he easily found and the "points" of instruction made use of. This worh heing issued in parts, now in manuscript, and capahle of change or e^nlargement, the editor will he thanhful for helpful suggestions from his profession- al brethren, before it is put into permanent booh form. J^. HAWKIJ^S. '^^^/?G£snPRt^^^'' Robert fuu INTRODUCTION, Each successive generation of engineers lias added cer- tain unwritten experiences to the general stock of knowledge relating to steam production, which have been communicated to their successors, and by them added to^ in their turn, it is within the province of this book to put in form for reference, these unwritten laws of conduct, which have passed into MAXIMS among engineers and firemen — a maxim being an undisputed truth, expressed in the shorti-st terms. Soliloquy op an Engineer. "Standing in tlie boiler room and looking around me, there are many things I ought to know a good deal about. Coal ! What is its quality ? How much is used in ten hours or twenty- four hours ? Is the grate under the boiler the best for an eco nomical consumption of fuel ? Can I, by a change in method of firing save any coal ? The safety valve. Do I know at what pressure it will blow off ? Can I calculate the safety-valve so as to be certain the weight is placed right ? Do I know how to calculate the area of the grate, the heating surface of the tubes and shell ? Do I know the construction of the steam gaugt >« ad vacuum-gauge ? Am I certain the steam-gauge is in- dicating correctly, neither over nor under the pressure of the steam ? What do I know about the setting of boilers ? About the size and quality of fire bricks? About the combination of carbon and hydrogen of the fuel with the oxygen of the atmosphere ? About oxygen, hydrogen and nitro- gen? About the laws of combustion ? About radiation and heating sur- faces ? "Do I know what are good non-conductors for covering of pipes, and why they are good ? Do I know how many gallons of water are in the boiler ? " What do I know about water and steam ? How many gallons of water are evaporated in twenty-four hours ? What do I know about iron and steel, boiler evaporation, horse-power of engines, boiler appendages and fittings ? " Can I calculate the area and capacity of the engine cylinder ? Can I take an indicator diagram and read it ? Can I set the eccentric ? Can I set valves ? Do I understand the construction of the thermometer, and know something about the pressure of the atmosphere, temperature and the best means for ventilation? Can I use a pyrometer and a salinometer? IKTEODUCTIOiq". " AVitliout goiii^ outside of my boiler and engine room I find these tilings are all about me — air, water, steam, heat, gases, motion, speed, strokes and revolutions, areas and capacities — how much do I know about these ? " How much can be learned from one lump of coal ? What was it, where did it come from ? When it is burned, what gases will it give off ? " And so with water. What is the composition of water ? What are the effects of heat upon it ? How does it circulate ? AVhat is the temperature of boiling water ? What are the temperatures under differ- ent pressures ? What is latent heat ? What is expansive force ? " These are the questioning thoughts which fill, while on duty, more or less vividly, the minds of both engineers and fire- men, and it is the purpose of this volume to answer the en- quiries, as far as may be without attempting too much ; for the perfect knowledge of the operations carried on within the boiler-room involves an acquaintance with many branches of science. In matters relating to steam engineering, it must be remembered that ^' art is long and time is short/' The utility of such a book as this is intended to be, no one will question, and he who would not be a ^^ hewer of wood and a drawer of water " to the more intelligent and well- informed mechanic, must possesses to a considerable extent the principles and rules embraced in this book ; and more especially, if he would be master of his profession and re- puted as one whose skill and decisions can be implicitly relied upon. The author in the preparation of the work has had two objects constantly in view ; first to cause the student to become familiarly acquainted with the leading principles of his profession as they are mentioned, and secondly, to furnish him with as much advice and information as possible within the reasonable limits of the work. While it is a fact that some of the matter contained in this work is very simple, and all of it intended to be very plain, it yet remains true that the most expert living engineer was at one time ignorant of the least of the facts and principles IlftBODUCTlOK. here given, and at no time in his active career can he ever get beyond the necessity of knowing fche primary steps by which he first achieved his sncoess. ' The following taken from the editorial columns of the lead- ing mechanical journal of the country contain the same sug- gestive ideas already indicated in the *' soliloquy of an engi- neer : '" ** There is amongst engineers in this country a quiet educational move- ment going on in matters relating to facts and principles underlying their work that is likely to have an important influence on industrial affairs. This educational movement is noticeable in all classes of workmen, but amongst none more than among the men in charge of the power plants of the country. It is fortunate that this is so, for progress once begun in such matters is never likely to stop. •' Engineers comprise various grades from the chief engineer of some large establishment, who is usually an accomplished mechanic, carrying along grave responsibilities, to the mere stopper and starter, who is en- gineer by courtesy only, and whose place is likelyto be soon filled by quite another man, so far as qualifications are concerned. Men ignorant of everything except the mere mechanical details of their work will soon have no place. * ' Scarcely a week passes that several questions are not asked by en gineers, either of which could be made the subject of a lengthy article. This is of interest in that it shows that engineers, are not at the present time behind in the way of seeking information. Out of about a thousand questions that went into print, considerable more than half w^ere asked by stationary engineers. These questions embrace many things in the way of steam engineering, steam engine management, construction, etc." The old meaning of the word lever was '^ a lifter " and this book is intended to be to its attentive student, a real lever to advance him in his life work ; it is also to be used like a ladder, which is to be ascended step by step, the lower rounds of which, are as important as the highesto It is moreover, the earnest wish of the editor that when some, perchance may have '' climbed up '' by the means of this, his work, they may in their turn serve as lifters to advance others, and by that means the benefits of the work widely extended. MATERIALS, The things with which the engineer has to deal in that place where steam is to be produced as an industrial age?it, are /. The Steam Generator, 2. Air. J. Fuel. ^. Water. 5. Steam Appliances. Starting with these points which form a part of every steam plant, however lim.it ed, however vast, the subject can easily be enlarged ttntil it embraces a thousand varied divisions extending throttgh all time and into every portio7i of the civilized world. It is within the scope of this work to so present the subjects specified, that the student may classify and arrange the inatter into truly scientific order. Maxims and Instructions, 13 MATERIALS. In entering the steam department^ where he is to be employ- ed, the eye of the beginner is greeted with the sight of coal, water, oil, etc., and he is told of invisible materials, such as air, steam and gases ; it is the proper manipulation of these seen and unseen material products as well as the machines, that is to become his life task. In aiding to the proper accomplishment of the yet untried problems nothing can be more useful than to know something of the nature and history of the different forms of matter entering into the business of steam production. Let us begin with Coal. The source of all the power in the steam engine is stored up in coal in the form of heat. And this heat becomes effective by burning it, that is, by its combustion. Coal consists of carbon, hydrogen, nitrogen, sulphur, oxygen and ash. These elements exist in all coals but in varying quantities. These are the common proportions of the best scrts : ANTHRACITE BITUMINOUS WOOD (average) DRY. Peat PEAT i WATEE Carbon . . . 90i 81 50 59 44 Hydrogen . 3* 5i 6 6 4i Nitrogen . . Oi 1 1 li 1 Sulphur . „ . 00 IJ p (25) Oxygen. . . 2i 6i 41 30 n\ Ash 4i 4f 2 31 3 1^0 100 100 100 100 In burning coal or other fuel atmospheric air must be in- troduced before it will burn; the air furnishes the oxygeuj without which combustion cannot take pl^cCo 14 Maxims and Instructions, MATERIALS. It is found that in burning one lb. of coal one hundred and fifty cubic feet of air must be used and in every day practice it is necessary to supply twice as much ; this is supplied to the coal partly through the grate bars, partly through the perforated doors, and the different devices for applying it already heated to the furnace. WOOD. Wood as a combustible, is divisible into two classes : 1st, the hard, compact and comparatively heavy, such as oak, ash, beech, elm. 2d, the light colored soft, and comparatively light woods as pine, birch, poplar. Wood when cut down contains nearly half moisture and when kept in a dry place, for several years even, retains from 15 to 20 per cent, of it. The steam producing power of wood by tests has been found to be but little over half that of coal and the more water in it the less its heating power. In order to obtain the most heating power from wood it is the practice in some works in Europe where fuel is costly, to dry the wood fuel thoroughly, even using stoves for the purpose, before using it. This *' hint '* may serve a good purpose on occasion. The composition of wood reduced to its elementary condition will be found in the table with coal. PEAT. Peat is the organic matter or vegetable soil of bogs, swamps and marshes — decayed mosses, coarse grasses, etc. The peat next the surface, less advanced in decomposition, is light, spongy and fibrous, of a yellow or light reddish-brown color ; lower down it is more compact, of a darker-brown color, and in the lowest strata it is of a blackish brown, or almost a black color, of a pitchy or unctuous feel. Peat in its natural condition generally contains from 75 to 80 per cent, of water. It sometimes amounts to 85 or 90 per cent, in which case the peat is of the consistency of mire. When wet peat is milled or ground so that the fibre is broken, crushed or cut, the contraction in drying is much Maxims and Instructions, MATERIALS. increased by this treatment ; and the peat becomes denser, and is better consolidated than when it is dried as it is cut from the bog; peat so prepared is known as condenf^ed peat, and the degree of condensation varies according to the natural heaviness of the peat. So effectively is peat consolidated and condensed by the simple process of breaking the fibres whilst wet. that no merely mechanical force of compression is equal to il. In the table the elements of peat are presented in two condi- tions. One perfectly dried into a powder before analyzing and the other with 25 per cent, of moisture. The value of peat as a fuel of the future is an interesting problem in view of the numerous inroads made upon our great natural coal fields. TAN. Tan, or oak bark, after having been used in the process of tanning is burned as fuel. The spent tan consists of the fibrous portion of the bark. Five parts of oak bark produce four parts of dry tan. STEAW. Two compositions of straw (as a fuel) is as follows : Water, - - - - 14 per cent. Combustible matter, - - 79 '* Ash, - - . - ^ a COKE, CHAEOOAL, PEAT OHAECOAL. These are similar substances produced by like processes from coal, wood, and peat and they vary in their steam-producing power according to the value of the fuels from which they are produced. The method by which they are made is termed carbonization, which means that all the gases are removed by heat in closed vessels or heaps, leaving only the carbon and the more solid parts like ashes, LIQUID AND GAS FUELS. Under this head come petroleum and coal gas, which are ob- tained in great variety and varying value from coal and coal oil. The heating power of these fuels stands in the front rank, as will be seen by the table annexed. 1 6 Maxims and Instructions, MATERIALS. There are kinds of fuel other than coal such as wood, coke, sawdust, tan bark, peat and petroleum oil and the refuse from oil. These are all burned with atmospheric air of which the oxygen comUnes with the combustible part of the fuel while the nitrogen passes off into the chimney as waste. The combustible parts of coal are carbon, hydrogen and sulphur and the unburnable parts are nitrogen, water and the incombustible solid matters such as ashes and cinder. In the operation of firing under a boiler the three first elements are totally consumed and form heat ; the nitrogen, and water in the form of steam, escapes to the flue, and the ashes and cinders fall under the grates. The anthracite coal retain their shape while burning, though if too rapidly heated they fall to pieces. The flame is generally short, of a blue color. The coal is ignited with dif- ficulty ; it yields an intense local or concentrated heat ; and the combustion generally becomes extinct while yet a consider- able quantity of the fuel remains on the grate. The dry or free burning bituminous coals are rather lighter than the anthracites, and they soon and easily arrive at the burning temperature. They swell considerably in coking, and thus is facilitated the access of air and the rapid and complete combustion of their fixed carbon. The method of firing with different sorts of fuel will be treated elsewhere. AIR. The engineer's success in the management of the furnace depends quite as much upon his handling the air in the right mixtures and proportions as it does in his using the fuel — for 1. Although invisible to the eye air is as much a material sulstance as coal or stone. If there were an opening into the interior of the earth which would permit the air to descend its density would increase in the same manner as it diminishes in the opposite direction. At the depth of about 34 miles it would be as dense as water, and at the depth of 48 miles it would be as dense as quicksilver ; and at the depth of about 50 miles as dense as gold. Maxims and Instructions, MATERIALS. 2. Air is not only a substance, but an impenetrable tody ; as for example : if \Ye make a hollow cylinder, smooth and closed at the bottom, and put a stopper or solid piston to it, no force will enable us to bring it into contact with the bottom of the cylinder, unless we permit the air within it to escape. 3. Air is a fluid which is proved by the great movability of its parts, flowing in all directions in great hurricanes and. in gentle breezes ; and. also by the fact that a pressure or blow is propagated through all parts and affects all parts alike. 4. It is also an elastic fluid, thus when an inflated bladder is compressed it immediately restores itself to its former situation; indeed, since air when compressed restores itself or tends to restore itself, with the same force as that with which it is com- pressed, it is a perfectly elastic body. 5. The weight of a column of air one square foot at the bottom is found to be 2156 lbs. or very nearly lo lbs. to the square inch, hence it is common to state the pressure of the atmosphere as equal to 15 lbs. to the square inch. It follows from these flve points that the engineer must con^ nder air as a positive, although unseen, factor with which Ms ivorh is to he accomplished. What air is composed of is a very important item of knowledge. It is made of a mixture of two invisible gases whose minute and inconceivably small atoms are mingled together like a parcel of marbles and bullets — that is while together they do not lose any of their distinctive qualities. The two gases are called nitrogen and oxygen, and of 100 parts or volumes of air 79 parts are of nitrogen and 21 parts of oxygen ; but by weight (for the oxygen is the heaviest) 77 of nitrogen and 23 of oxygen. The oxygen is the part that furnishes the heat by uniting with the coal — indeed without it the process of combustion would be impossible : of the two gases the oxygen is burned in the furnace, more or less imperfectly, and the nitrogen is wasted. jS Maxims and Instructions, MATERIALS. Table of Evaporatiok. In order to arrive at the money value of tlie various f ie!a heretofore described a method of composition has been arrived at which gives very accurately their comparative worth. The rule is too advanced for this elementary work, but the follow- ing results are plainly to be understood, and will be found to be of value. Lbs. of FneL Temperature of water ^ Coal, 14.62 lbs, . of water. Coke, - • - - 14.02 « Wood, 8.07 €% Wood, 25 the carbonizing of the tar in the delivery pipe, thus choking it up and rendering it uncertain in action. To obviate these Maxims and Instructions. j?i FIRING WITH VARIOUS FUELS. difficulties vario-us plans have been resorted to, but the best means for overcoming them are thus described ; fix the tar supply tank as near the furnace to be supplied as convenient, and one foot higher than the tar-mjector inlet A cock is screwed into the side of the tank, to which is attached a piece of composition pipe f -inch in diameter, ten inches long. To this a "2 -inch iron service pipe is connected, the other end of which is joined to the injector. By these means it is found that at the ordinary temperature of the tar well (cold weather excepted) loar gallons of tai pei hour are delivered in a con- stant steam into the furnace. If more tar is requixed, the piece of f -inch tube must be shortened, or a larger tube substituted, and if less tar is required it must be lengthened. The risk of stoppage in the nozzle of the injector is overcome by the steam jet, which scatters the tar into spray and thus keeps everything clear. Trouble being occasioned by the retorts becoming too hot, in which case, on shutting off the flow of tar for a while, the tar in the pipe carbonized and caused a stoppage, a remov- able plug injector is fitted and ground in like the plug of a cock, having inlets on either side for tar and steam. This plug injector can be removed, the tar stopped in two seconds and refixed in a similar time. The shell of the injector is firmly bolted to the top part of the door frame. The door is swung horizontally, having a rack in the form of a quadrant, by which it is regulated to any required height, and to admit any quantity of air. FiRii^TG WITH Straw. — The operation of burning straw un- der a boiler consists in the fuel being fed into the furnace only as fast as needed. When the straw is handled right, it makes a beautiful and very hot flame and no smoke is seen com ing from the stack. The whole secret of getting the best results from this fuel is to feed it into the furnace in a gradual stream as fast as consumed. When this is done complete com- bustion is the result. A little hole may be drilled in the smoke- box door, so that the color of the fire can be seen and fire is handled accordingly. When the smoke comes from the stack the color of the flame is that of a good gas jet. Bj feeding a ^2 Maxims and Instructions. FIRING WITH VARIOUS FUELS. little faster the color becomes darker and a little smoke comes from tlie stack ; feeding a little faster tlie flame gets quite dark and? the smoke blacker; faster still, the flame Ig extinguished, clouds of black smoke come from the stack, and the pressure is falling rapidly. FiRiKG WITH OiLc— Great interest is now manifested in the use of oil as fuel. There are various devices used for this pur- pose, most of them depending upon a steam jet to atomize the oil, or a system of retorts to first heat the oil and convert it into gas, before being burned. Another method in successful operation is the use of com- pressed air for atomizing the oil — air being the element, nature provides for the complete combustion of all matter. The cleanliness of the latter system and its comparative freedom from any odor of oil or gas and its perfect combustion, all re- commend it. Among the advantages claimed for the use of oil over coal are 1, uniform heat ; 2, constant pressure of steam ; 3, no ashes, clinkers, soot or smoke, and consequently clean flues ; 4, uniform distribution of heat and therefore less strain upon the plates. FiRiKG OK AN OcEAK Steamer like the '' Umhria" i\iQ men come on in gangs of eighteen stokers or firemen and twelve coal passers, and the '^ watch "' lasts four hours. The '' Umhria " has 72 furnaces, which require nearly 350 tons of coal a day, at a cost of almost 120,000 per voyage. One hun- dred and four men are employed to man the furnaces, and they have enough to do. They include the chief engineer, his three assistants, and ninety stokers and coal passers. The stoker comes to work wearing only a thin undershirt, light trousers, and wooden shoes. On the '* Umbria ^' each stoker tends four furnaces. He first rakes open the furnaces, tosses in the coal, and then cleans the fire, that is, pries the coal apart with a heavy iron bar, in order that the fire may burn freely. He rushes from one furnace to another, spending perhaps two or three minutes at each. Then he dashes to the air pipe, takes his turn at cooling off, and waits for another Maxims ancr Instructions. Jj FIRING WITH VARIOUS FUELS. call to his furnace, which comes speedily. When the '^ watch ** is over, the men shuffle off, dripping with sweat from head to foot, through long, cold galleries to the forecastle, where they turn in for eight hours. Four hours of scorching and eight hours sleep make up the routine of a fireman's life on a voyage. The temperature is ordinarily 120°, but sometimes reaches 160°; and the work then is terribly hard. The space between the furnaces is so narrow that when the men throw in coal they must take care when they swing back their shovels, lest they throw their arms on the furnace back of them . In a recent trial of a government steamer the men worked willingly in a temperature of 175°, which, however, rose to 212° or the heat of boiling water. The shifts of four hours were reduced to two hours each, but after sixteen men had been prostrated, the whole force of thirty-six men refused to submit to the heat any longer and the trial was abandoned. There is no place on ocean or land, where more suffering is inflicted and endured by human beings than in these h holes, quite projDcrly so called ; it is to be hoped that the efforts towards reform in the matter will not cease until completely successful. Firing of Sawdust akd Shavings. — '^The air was forced into the furnace with the planer shavings at a velocity of about 12 feet per second, and at an average temperature of about 60 degrees Fahrenheit. The shavings were forced through a pipe 12 inches in diameter, above grate, into the combustion chamber. The pipe had a blast gate to regulate the air in order to main- tain a pressure in the furnace, which a little more than bal- anced the ascending gases in the funnel or chimney. All the fireman had to do was to keep the furnace doors closed and watch the water in the gauges of his boiler. The combustion in the furnace was complete, as no smoke was visible. The shavings were forced into the combustion chamber in a spray- like manner, and were caught into a blaze the moment they entered. The oxygen of the air so forced into the furnace along with the shavings gave full support to the combustion. 34 Maxims and Instructions, FIRING WITH VARIOUS FUELS. The amount of shavings consumed by being thus forced into the furnace was about fifty per cent, less than the amount consumed, when the fireman had to throw them in with his shovel." It is an important ^' point " when burning shavings or saw- dust with a blast, to keep the blower going without cessation, as there have been disastrous accidents caused by the flames going up the shutes, thence through the small dust tubes leading from the bin to the various machines. In firing ^' shavings^' by hand, it is necessary to bum them from the top as otherwise the fire and heat are only pro- duced when all the shavings are charred. To do this, provide a a half inch gas pipe, to be used as a light poker ; light the shaving fire, and when nearly burned take the half -inch pipe and divide the burning shavings through the middle, banking them against the side- walls as shown in 1^'ig. 9. Kow feed a pile of new shavings into the centre on the clean grate bars, as shown in Fig. 10, and close the furnace doors. The shavings will begin to burn from above, lighted from the two side fires, the air will pass Fig. 10. through the bars into the shav- ings, where it will be heated and unite with the gas, making the combustion perfect, generating heat, and no smoke, and the fire will last much longer and require not half the labor m itoking. Maxims and Instructions. 35 FIRING A LOCOMOTIVE. ^.^ This figure exhibits the interior of the furnace of a locomo- tive engine, which varies greatly from the furnace of either a land or marine boiler. This difference is largely caused by the method of applying the draught for the air supply; in the locomotive this is effected by conducting the exhaust steam through pipes from the cylinders to the smoke-box and allow- ing ib to escape up the smoke stack from apertures called exhaust nozzles; the velocity of the steam produces a vacuum, by which the products of combustion are drawn into the smoke- box with great power and forced out of the smoke stack into the open air. To prevent the too quick passage of the gases into the flues an appliance called a fire brick arch has been adopted and has proved very efficient. In order to be self supporting it is built in the form of an arch, supported by the two sides of the fire box which serve for abutments. The arch has been sometimes replaced by a hollow riveted arrangement called a water table designed to increase the fire surface of the boiler. 36 Maxims and Instructions, FIRING A LOCOMOTIVE. Firing a Locomotive. — T^o rules can possibly be given for firing a locomotive which would not be more misleading than helpful. This is owing to the great variations which exist in the circumstances of the use of the machine, as well as the differences which exist in the various types of the locomotive. These variations may be alluded to, but not wholly described. 1. They consist of the sorts of fuel used in different sections of the country and frequently on different ends of the same rail- road; hard coal, soft coal, and wood all require different man- agement in the furnace. 2. The speed and weight of the train, the varying number of cars and frequency of stopping places, all influence the duties of the fireman and tax his skill. 3. The temperature of the air, whether cold or warm, dry weather or rain, and night time and day time each taxes the skill of the fireman. Hence, to be an experienced fireman in one section of the country and under certain circumstances does not warrant the assurance of success under other conditions and in another loca- tion. The subject requires constant study and operation among not only " new men '' but those longest in the service. More than in any other case to be recalled, must the fireman of a locomotive depend upon the personal instruction of the engineer in charge of the locomotive. FiEiKG WITH Tan Bark. — Tan bark can be burned upoB common grates and in the ordinary furnace by a mixture of bituminous screenings. One shovel full of screenings to four or five of bark will produce a more economical result than the tan bark separate, as the coal gives body to the fire and forms a hot clinker bed upon which the bark may rest without falling through the spaces in the grate bars, and with the coal, more air can be introduced to the furnace. The above relates to common furnaces, but special fire boxes have been recently put into operation, fed by power appli- ances, which work admirably. The '* point '^ principally to be noted as to the efficacy of tan bark as a fuel, is to the effect, that like peat, the drier it is the more valuable is it as a f ueL Maxims and Instructions, jy POINTS RELATING TO FIRING. The Process of Boiling. Let it be remembered that the boiling spoken of so often is really caused by the formation of the steam particles, and that without the boiling there can be but a very slight quantity of steam produced. While pure water boils at 212°, if it is saturated with common salt, it boils only on attaining 224°, alum boils at 220°, sal ammoniac at 236°, acetate of soda at 256°, pure nitric acid boils at 248°, and pure sulphuric acid at 620°. Ok the First Application of Heat to water small bubbles soon begin to form and rise to the surface; these consist of air, which all water contains dissolved in it. When it reaches the boiling point the bubbles that rise in it are principally steam. In the case of a new plant, or where the boiler has some time been idle it is frequently advisable to build a smaF fire in the base of the chimney before starting the boiler fires Thit, will serve to heat the chimney and drive out any moist ire that may have collected in the interior and will frequently prevent the disagreeable smoking that often follows the building of a fire in the furnace. Always bear in mind that the steam in the boilers and engines is pressing outward on the walls that confine it in every direction; and that the enormous forces you are handling, warn you to be careful. When starting fires close the gauge cocks and safety valve as soon as steam begins to form. Go SLOW. It is necessary to start all new boilers very slowly. The change from hot to cold is an immense one in its effects on the contraction and expansion of the boiler, the change of dimension by expansion is a force of the greatest magnitude and cannot be over-estimated. Leaks which start in boilers that were well made and perfectly tight can be attributed to this cause. Something must give if fires are driven on the start, and this entails trouble and expense that there is no occa- sion for. This custom applies to engines and steam pipes as well as to boilers. No one of any experience will open a stop yalve and let a full head of live steam into a cold line of pipe or a cold engine. 3^ Maxims and Instructions, POINTS RELATING TO FIRING. To preserve the grate« bars from excessive heat, when first firing a boiler, it is well to sprinkle a thin layer of coal upon the grates before putting in the shavings and wood for starting the fire. This practice tends greatly to prolong the life of the grate-bars. The fuel shonld generally be dry when usedu Hard coal, however, may be dampened a little to good advantage, as it is then less liable to crowd and will burn more freely. Air, high temperature, and sufficient time are the principal points in firing a steam boiler. In first firing up make sure that the throttle valve is closed, in order that the steam first formed may not pass over into the engine cylinder and fill it with water of condensation. If the throttle valve leak steam it should be repaired at the first opportunity. Keep all heating surfaces free from soot and ashes. Eadiant rays go in all directions, yet they act in the most efficient manner when striking a surface exactly at a right angle to their line of movement. The sides of a fire-box are for that reason not as efficient as the surface over the fire, and a flat surface over the fire is the best that can be had, so far as that fact alone is considered. When combustion is completed in a furnace then the balance of the boiler beyond the bridge wall can be utilized for taking up heat from the gases. The most of this heat has to be absorbed by actual contact ; thus by the tubes the gases are finely divided, allowing that necessary contact. Combustion should be completed on the grates for the reason that it can be effected there at the highest temperature. When this is accomplished, the fullest benefit is had from radiant heat striking the bottom of the boiler — it is just there that the tulk of the work is done. There must necessarily be some waste of heat by its passing up the chimney to maintain draft. It is well to have th« Maxims and Instructions, ^p POINTS RELATING TO FIRING. 3, as they enter the chimney, as much below 600 deg. F. (down to near the temperature of the steam) as you can and yet maintain perfect combustion. Every steam engine has certain well-defined sounds in action which we call noises, for want of a better term, and it is upon them and their continuance that an engineer depends for assurance that all is going well. This remark also applies to the steam boiler, which has, so to speak, a language of its own, varying in volume from the slight whisper which announces a leaking joint to the thunder burst which terribly follows a destructive explosion. The hoarse note of the safety valve is none the less significant because common. The dampers and doors to the furnace and ash pit should always be closed after the fire has been drawn, in order to keep the heat of the boiler as long as possible. But the damper must never be entirely closed while there i? fire on the grate as explosions dangerous in their character might occur in the furnace from the accumulated gases. Flues or tubes should often be swept, as soot, in addition to its liability to becoming charged with a corroding acid, is a non-conductor of heat, and the short time spent in cleaning them will be repaid by the saving of labor in keeping up steam. In an establishment where they used but half a ton of bituminous coal per day, the time of raising steam in the morning was fifty per cent, longer when the tubes were unswept for one week than when they were swept three times a week. Smoke will not be seen if combustion is perfect. Good firing will abate most of the smoke. Coals, at the highest furnace temperature, radiate much heat, whereas gases ignited at and beyond the bridge wall radiate comparatively little heat — it is a law in nature for a solid body highly heated to radiate heat to another solid body. Dry Ais'D Cleak is the condition in which the boiler shouM be kept, i, e., dry outside and clean bothinside and out. Maxims and Instructions, POINTS RELATING TO FIRING To haul his furnace fire and open the safety vahe before seeking his own safety or the preservation of property, is the duty of the fireman in the event of fire threatening to burn a whole establishment. Many, now prominent, engineers have made their first repu- tation by remembering to do this at a critical time. Whek watee is pumped into the boiler or allowed to run in, some opening must be given for the escape of the contained air, usually the most convenient way is to open the upper guage cock after the fire has been lighted until cloudy steam begins to escape. In a snmmaiy of experiments made in England, it is stated that : — ** A moderately thick and hot fire with rapid draft uniformly gave the best results/* "' Combustion of black smoke by additional air was a loss/* *' In all experiments the highest result was always obtamed when all the air was introduced through the fire bars." ** Difference in mode of firing only may produce a difference of 13 per cent.'* (in economy). The thickness of the fire under the boiler should be in accordance with the quality and size of the fuel. For hard coal the fire should be as thin as possible, from three to six inches deep ; when soft coal is used, the fire should be thicker, from five to eight inches deep. If it is required to bum coal dust without any change of grates, wetting the coal is of advantage ; not that it increases its heat power, but because it keeps ib from falling tlirough the grates or going up the chimney. The same is true of burning shavings ; by watering they are held in the furnace, and the firing is done more easily and with better results. Stirkikg the Fire should be avoided as much as possible ; firing should be performed evenly and regularly, a little at a time, as it causes waste fuel to disturb the combustion and by making the fuel fall through the grates into the ash pit ; hence do not ** clean** fires oftener then absolutely necessary. Maxims and Instructions. POINTS RELATING TO FIRING. The slower the velocity of the gases before they pass the damper, the more nearly can they be brought down to the temperature of the steam, hence with a high chimney and strong draft the dampers should be kept nearly closed, if the boiler capacity will permit it. No arbitrary rule can be laid down for keeping fires thick or thin. Under some conditions a thin fire is the best, under others a thick fire gives best economy. This rule, however, governs either case : you must have so active a fire as to give strong radiant heat. One of the highest aims of an expert fireman should be to keep the largest possible portion of his grate area in a condition to give great radiant heat the largest possible part of a day- using anthracite coal by firing light, quick and often, not covering all of the incandescent coals. Using bituminous coal, hand firing, by coking it very near the dead plate, allowing some air to go through openings in the door, and by pushing toward the bridge wall only live coals — when slicing, to open the door only far enough to work the bar ; this is dono with great skill in some cases. Regulating the Deaft. — This should be done so as to admit tlie exact quantity of air into the furnace, neither too much nor too little. It should be remembered that fuel can- not be burned without air and if too much air is admitted it cools the furnace and checks combustion. It is a good plan to decrease the draft when firing or cleaning out, by partly closing the damper or shutting off the air usually admitted from below the grates ; this is to have just draught enough to pieTent the flame from rushing out when the door is opened. By luminous fiame is generally meant that which burns witK a bright yellow to white color. All flame under a boiler is not luminous, sometimes the whole or a part of it will be red or blue. The more luminous the flame, that is to say, the nearer white it is, the better combustion. 4^ Maxims and Instructions, RULES RELATING TO FIRING. To DETERMII^E THE TEMPERATURE OF A FUE:N"ACE FIRE the following table is of use. The colors are to be observed and the corresponding degrees of heat will be approximately as follows: Faint red 960° F. Bright red 1,300° F. Cherry red 1,600° F. Dull orange 2,000° F. Bright orange 2,100° F. White heat 2,400° F. Brilliant white heat 2,700° F. That is to say, when the furnace is at a '^ white heat " the heat equals 2,400 degrees Fahrenheit, etc. Another method of finding the furnace heat is by submitting a small portion of a particular metal to the heat. Tin melts at 442° F. Lead '' " 617° F. Zinc *' '' .700° F. nearly. Antimony melts at 810 to 1,150° F. Silver melts at 1,832 to 1,873° F. Cast Iron melts at 2,000° F. nearly. Steel " •' 2,500° F. '' Wrought Iron melts at 2, 700° F. " Hammered Iron melts at 2,900° F. '* FOAMING m BOILERS. The causes are — dirty water, trying to evaporate more water than the size and construction of the boiler is intended for, taking the steam too low down, insufficient steam room, im- perfect construction of boiler, too small a steam pipe and some- times it is produced by carrying the water line too high. Too little attention is paid to boilers with regard to their evaporating power. W^here the boiler is large enough for the water to circulate, and there is surface enough to give off the steam, foaming never occurs. As the particles of the steam have to escape to the surface of the water in the boiler, unless that is in proportion to the amount of steam to be generated, it will be delivered with such violence that the water will be mixed with it, and cause foaming. Maxims and Instructions, ^^ FOAMING IN BOILERS. For violent ebollition a plate hung over the hole where the steam enters the dome from the boiler, is a good thing, and prevents a rush of water by breaking it, when the throttle is opened suddenly. In cases of very violent foaming it is imperative to check the draft and cover the fires. The steam pipe may be carried through the flange six inches into the dome — which will prevent the water from entering the pipes by following the sides of the dome as it does. A similar case of priming of the boilers of the IT. S. Steamer Galena was stopped by removing some of the tubes under the smoke stack, and substituting bolts. Clean water, plenty of surface, plenty of steam room, large steam pipes, boilers large enough to generate steam without forcing the fires, are all that "is required to prevent foaming. A high pressure insures tranquillity at the surface, and the steam itself being more dense it comes away in a more compact form, and the ebullition at the surface is no greater than at a lower pressure. When a boiler foams it is best usually to close the throttle to check the flow, and that keeps up the pressure and lessens the sudden delivery. Too many flues in a boiler obstruct the passage of the steam from the lower part of the boiler on its way to the surface — this is a fault in construction. An engineer who had been troubled with priming, finally removed 36 of the tubes in the centre of the boiler, so as to centralize the heating effect of the fire, thereby increasing the rapidity of ebullition at the centre, while reducing it at the circumference. The effect of the change was very marked. The priming disappeared afc once. The water line became nearly constant, the extreme variation being reduced to two inches. 44 Maxims and Instructions, A CHAPTER OF DON'TS. Which is another way of repeating what has already been said, 1. DotV^t empty the boiler when the brick work is hot. 2. Don't pump cold water into a hot boiler. 3. Don^t allow filth of any kind to accumulate around the boiler or boiler room. 4. Uofl't leave your shovel or any other tool out of its appointed place when not in use. 5. Don^t fail to keep all the bright work about the boiler neat and " shiny." 6. Don't forget that negligence causes great loss and danger. 7. Don't fail to be alert and ready-minded and ready- headed about the boiler and furnace. 8. Don't read newspapers when on duty. 9. Don't fire up too quickly. 10. Don't let any water or dampness come on the outside of your boiler. 11. Don't l^t Siny dampness get into the boiler and pipe coverings. 12. Z)o^^< fail to see that you have plenty of water in the boiler in the morning. 13. Don't fail to keep the water at the same height in the boiler all day. 14. Don't let any one talk to you when firing. 15. Don't allow water to remain on the floor about the boiler. 16. Don't fail to blow off steam once or twice per day- according as the water is more or less pure. 17. Don't fail to close the blow-off cock, when blowing off, when the water in the boiler has sunk to one and a half inches. 18. Dont fail, while cleaning the boiler, to examine and clean all cocks, valves and pipes and look to all joints and packings. Mixxims and Instructions. 4s A CHAPTER OF DONTS. J 9. lyouH commence cleaning the boiler until it has had time to cool. 20. DonH forget daily to see that the safety valve moves freely and is tight. 21. Don^t fail to clean the boiler inside frequently and carefully. 22. Don*t fail to notice that the steam gauge is in order. 23. Don't fail to keep an eye out for leaks and have them repaired immediately, no matter how small. 24. Don^t fail to empty the boiler every week o^ two and re- fill it with fresh water. 25. DonH let any air into the furnace, except what goes through the grate bars, or the smoke burners, so called, by which the air is highly heated. 26. Don't increase the load on the safety valve beyond the pressure allowed by the inspector, 27. Don^t fail to open the doors of the furnace and start the pump when the pressure is increased beyond the amount allowed, hut 28. Don^t fail to draw the fires when there is danger from the water having fallen too low. 29. Don^t fail to check the fire — if too hot to draw, do it with fresh coal, damp ashes, clinkers or soil ; and 30. Don't fail to open the doors of the furnace and close the ash pit doors at the time the fire is checked — and 31. Don't decrease the steam pressure by feeding in water or suddenly blowing off steam, and 32. Don't touch the safety valve, even if it be opened or closed, and 33. Don't change the feed apparatus if it is working, or the throttle- valve be open ; let them both remain as they are for a short time, and 34. Do n't fail to change them very cautiously and slowly when you close them, and d6. Don't fail to be very cool and brave while resolute in gbserving these last seven '' Dent's.'' Maxims and Instructions. A CHAPTER OF DONTS. 36. Don^t fail to keep yourself neat and tidy. 37. Don^t fail to be polite as well as neat and brave. 38. I>on'f fail to keep the tubes clear and free from soot and ashes. 39. DonH let too many asbes gather in the ashpit. 40. I>on^t disturb the fire when it is burning good nor stir it up too often. 41. DonH be afraid to get instruction from books and engineering papers. 43. JDon^t fail to make an honest self-examination as to points upon which you may be ignorant, and really need to know in order to properly attend to your duties. 43. JDon^t allow too much smoke to issue from the top of the chimney if the cause lies within your power to pre- vent it. 44. DonH think that after working at firing and its kindred duties for a year or two that the whole subject of engineering has been learned. 45. Don^t forget that one of the best helps in getting for- ward is the possession of a vigorous and well balanced mind and body — this covers temperance and kindred vir- tues and a willingness to acquire and impart knowledge. 46. Don^t forget to have your steam gauge tested at least once in three months. 47. DonH use a wire or metallic rod as a handle to a swab in cleaning the glass tube of a water gauge for the glass may suddenly fiy to pieces when in use within a short time afterwards. 48. JDonH forget that steam pumps require as much atten- tion as a steam engine. 49. Dofi^t run a steam pump piston, unless in an emergency, at a speed exceeding 80 to 100 feet per minute. 60. Don^t do anything without a good reason for it about the engine or boiler, bat when you are obliged to d« anything, do it thoroughly and as quickly as possible* Maxims and Instructions, ^y A CHAPTER OF DONT'S. 51. Do7iH forget to sprinkle a thin layer of coal on the grates before lighting the shavings and wood in the morning. This practice preserves the grate bars. 52. DonH don't take the cap off a bearing and remove the upper brass simply to see if things are working well ; if there is any trouble it will soon give you notice, and, besides, you never can replace the brass in exactly its former position, so that you may find that the bearing will heat soon afterwards, owing to your own uncalled- for interference. 53. Don^t put sulphur on a hot bearing, unless you intend to ruin the brasses. 54. Don't use washed waste that has a harsh feel, as the chemicals used in cleansing it have not been thoroughly removed. 55. I>ofl'tf in case of an extensive fire, involving the whole business, rush off without drawing the fires, and raising and. propping open the safety valve of the boiler. 56. Dofi't fail to preserve your health, for ^'a sound mind in a sound body " is beyond a money valuation. 57. Don't fail to remember that engineers and firemen are in control of the great underlying force of modern civ- ilization; hence, to do nothing to lower the dignity of the profession. 58. Don't forget that in the care and management of the steam boiler the first thing required is an unceas- ing watchfulness —watch-care. 59. Don't forget that an intemperate, reckless or indiffer- ent man has no business in the place of trust of a steam boiler attendant. 60. Don't allow even a day to pass without adding ono or more facts to your knowledge of engineering in some of its branches. ^8 Maxims ana Instructions. STEAM GENERATORS. In the examinations held by duly appointed officers to determine the fitness of candidates for receiving an engineer's license the principal stress is laid upon the applicant's know- ledge of the parts and true proportions of the yarious designs of steam boilers, and his experience in managing them. In fact, if there were no boilers there would be no examin- ations, as the laws are framed, certificates issued and steam boiler inspection companies formed to assure the public safety in life, limb and property, from the dangers arising from so- called mysterious boiler explosions. Hence an almost undue proportion t)f engineer's examina- tions are devoted to the steam boiler, its management and con- struction. But the subject is worthy of the best and most thoughtful attention. Every year adds to the number of steam boilers in use. \^ith the expanding area and growth of pop- ulation, the number of steam plants are multiplied and in turn each new steam boiler demands a careful attendant. There is this difference between the boiler and the engine. When the latter is delivered from the shop and set up, it does its work with an almost unvarying uniformity, while the boiler is a constant care. It is admitted that the engine has reached a much greater state of perfection and does its duty with very much more reliability than the boiler. Even when vigilant precautions are observed, from the moment a steam boiler is constructed until it is finally de- stroyed there are numerous insidious agents perpetually at work which tend to weaken it. There is nothing from which the iron can draw sustenance to replace its losses. The at- mosphere without and the air within the boiler, the water as it Maxims and Instructions. 49 STEAM GENEEATOES. ca;or3 tbrough the feed-pipe and containing mineral and organic substances, steam into which the water is converted, the sediment which is precipitated by boiling the water, the fire and the sulphurous and other acids of the fuel, are all natural enemies of the iron; they sap its strength, not only while the boiler is at work and undergoing constant strain, but in the morning before fire is started, and at noon, night, Sun- days, and other holidays it is preyed upon by these and other corroding agents. These are the reasons which impress the true engineer with a constant solicitude regarding the daily and even momentary action of the steam generator. Desckiptioi^. The Steam Boiler in its simplest form was simply a closed -vessel partly filled with water and which was heated by a fire box, but as steam plants are divided into two principal parts, the engine and the boiler, so the latter is divided again into the furnace and boiler, each of which is essential to the other. The furnace contains the fuel to be burnt, the boiler contains the water to be evaporated. There must be a steam space to hold the steam when generated ; heating surface to transmit the heat from the burning fuel to the water; a chimney or other apparatus to cause a draught to the furnace and to carry away the products of combustion ; and various fittings for supplying the boiler with water, for carrying away the steam when formed to the engine in which it is used ; for allowing steam to escape into the open air when it forms faster than it can be used ; for ascertaining the quantity of water in the boiler, for ascertain- ing the pressure of the steam, etc., all of which, together with the engine and its appliances is called A steam plant. The forms in which steam generators are built are numerous, but may be divided into three classes, viz. : stationary, loco- motive and marine boilers, which terms designate the uses for which they are intended ; in this work we have to deal mainly with the first-named, although a description with illustration is given of each type or form. 50 Maxims and Instructions, AN UPRIGHT STEAM BOILER. To illustrate the operations of a steam generator, we give the details of an appliance, which may be compared to the letter A of the alphabet, or the figure 1 of the numerals, so simple is it. Fig. 11, is an elevation of boiler, fig. 12 a vertical section through its axis, and fig. 13 a horizontal section through the furnace bars. Fig. 11. Fig. 12. The type of steam generator here exhibited is what is known as a vertical tubular boiler. The outside casing or shell is cylindrical in shape, and is composed of iron or steel plates riveted together. The top, which is likewise composed of the same plates is slightly dome-shaped, except at the center, which is away in order to receive the chimney a, which is round in shape and formed of thin wrought iron plates. The interior is shown in vertical section in fig. 12. It consists of a furnace chamber, h, which contains the fire. The furnace is formed like the shell of the boiler of wrought iron or steel plates by flanging and riveting. The bottom is occupied by the grating, on which rests the incandescent fuel. The grating consists of Maxims and Instructions. 5/ UPRIGHT STEAM BOILERS. a number of cast-iron bars, d (fig. 12), and shown in plan in fig. 13, placed so as to have interstices between them like the grate of an ordinary fireplace. The bottom of the furnace is firmly secured to the outside shell of the boiler in the manner shown in fig. 12. The top covering plate cc, is perforated with a num- ber of circular holes of from one and a half to three inches diameter, according to the size of the boiler. Into each of these holes is fixed a vertical tube made of brass, wrought iron, or steel, shown at fff (fig. 12). These tubes pass through similar holes, at their top ends in the plate g, which latter is firmly riveted to the outside shell of the boiler. The tubes are also firmly attached to the two plates, cc^ g. They serve to convey the flame, smoke, and hot air from the fire to the smoke box, h, and the chimney, a, and afc the same time their sides provide ample heating surface to allow the heat contained in the products of combustion to escape into the water. The fresh fuel is thrown on the grating when required through the fire door, A (fig. 11). The ashes, cinders, etc., fall between the fire bars into the ash pit, B (fig. 12). The water is contained in the space between the shell of the boiler, the furnace chamber, and the tubes. It is kept at or about the level, ww (fig. 12), the space above this part being reserved for the steam as it rises. The heat, of course, escapes into the water, through the sides and top plate of the furnace, and through the sides of the tubes. The steam which, as it rises from the boiling water, ascends into the space above ww, is thence led away by the steam pipe to the engine. Unless consumed quickly enough by the engine, the steam would ac- cumulate too much within the boiler, and its pressure would rise to a dangerous pomt. To provide against this contingency the steam is enabled to escape when it rises above a certain pressure through the safety valve, which is shown in sketch on the top of the boiler in fig. 11. The details of the construction of safety valves will be found fully described in another section of this work, which is devoted exclusively to the consideration of boiler fittings. In the same chapters will be found full de- scriptions of the various fittings and accessories of boilers, such as the water and pressure gauges, the apparatus for feeding the boiler with water, for producing the requisite draught of air to maintain the combustion, and also the particulars of the con- struction of the boilers themselves and their furnaces. 52 Maxims and Instructions. THE GROWTH OF THE STEAM BOILER. After the first crude forms, such as that used in connection with the Baranca and Newcoman engine, and numerous others. The steam boiler which came into very general use was th^ 'plain cylinder holier. An illustration is given of this in figures 14 and 15. It consists of a cylinder A, formed of iron plate with hemis- pherical ends B.B. set horizontally in brick work C. The lower part of this cylinder contains the water, the upper part the steam. The furnace D is outside the cylinder, being beneath one end ; it consists simply of grate bars e e set in the brick work at a convenient distance below the bottom of the boiler. The sides and front of the furnace are walls of brick work, which, being continued upwards support the end of the cylinder. The fuel is thrown on the bars through the door which is set in the front brick work. The air enters between Fig. 14. the grate bars from below. The portion below the bars is called the ash pit. The flame and hot gasses, when formed, first strike on the bottom of the boiler, and are then carried forward by the draft, to the so-called bridge wall 0, which is a projecting piece of brick work which contracts the area of the flue n and forces all Fig. 13. Maxims and Instructions. ^^ THE GROWTH OF THE STEAM BOILER. the products of combustion to keep close to the bottom of the boiler. Thence the gasses pass along the flue n, and return part one side of the cylinder in the flue m (fig. 15) and back again by the other side flue m to the far end of the boiler, whence they escape up the chimney. This latter is provided with a door or damper p, which can be closed or opened at will, so as to regulate the draught. This boiler has been in use for nearly one hundred years, but has two great defects. The first is that the area of heating surface, that is the parts of the boiler in contact with the flames, is too small in proportion to the bulk of the boiler ; the second is, that if the water contains solid matter in solution, as nearly all the water does to a greater or less extent, this matter becomes deposited on the bottom of the boiler just where the greatest evaporation takes place. The deposit, being a non-conductor, prevents the heat of the fuel from reaching the water in sufficient quantities, thus rendering the heating surface inefficient ; and further, by preventing the heat from escaping to the water, it causes the plates to become unduly heated, and quickly burnt out. There is another defect belonging to this system of boiler to which many engineers attach great importance, viz. : that the temperature in each of the three flues n, m, m' is very differ- ent, and consequently that the metal of which the shell of the boiler is composed expands very unequally in each of the flues, and cracks are very likely to take place when the effects of the changes of temperature are most felt. It will be noted that the flames and gasses in, this eailiest type of steam boiler make three turns before reaching the chimney, and as these boilers were made frequently as much as 40 feet long it gave the extreme length of 120 feet to the heat products. 54 Maxims and Instructions. THE GROWTH OF THE STEAM BOILER. The Corn^ish Boiler is the next form in time and ex- cellence. This is illustrated in figures 16 and 17. It consists also of a cylindrical shell A, with flat ends as ex- hibited in cuts. The furnace, however, instead of being sit- uated underneath the front end of the shell, is enclosed in it in a second cylinder B, having usually a diameter a little greater than half that of the boiler shell. The arrangement of the grate and bridge is evident from the diagram. After passing the bridge wall the heat products travel along through the in- ternal cylinder By till they reach the back end of the boiler ; then return to the front again, by the two side flues in, m,,' and thence back again to the chimney by the bottom of flue n. In this form of boiler the heating surface exceeds that of the last described by an amount equal to the area of the internal flues, while the internal capacity is diminished by its cubic contents ; hence for boilers of equal external dimensions, the ratio of heating surface to mass of water to be heated, is greatly increased. Boilers of this sort can, however, never be made of ""^^^=^-^^^^:^ B ^j» rv n Fig. 16. as small diameters as the plain cylindrical sort, on account of the necessity of finding room inside, below the water level, for the fur- nace and flue. The disadvantage, too, of the deposits mentioned in the plain cylinder is, to a great extent got Fig, VI. over in the Cornish boiler, for the Maxims and Instructions, 55 THE GROWTH OF THE STEAM BOILER. bottom, where the deposit chiefly takes place, is the coolest instead of being the hottest part of the heating surface. But the disadyantage of unequal expansion also exists in this type of boiler, as the internal flue in the Cornish system is the hottest portion of the boiler, and consequently undergoes a greater lengthways expansion than the flues. The result is to bulge out the ends, and when the boiler is out of use, the flue returns to its regular size, and thus has a tendency to work loose from the ends to which it is riveted and if the ends are too rigid to move, a very serious strain comes on the points of the flue. Even while in use the flue of a Cornish boiler is liable to un- dergo great changes in temperature, according to the state of the fire ; when this latter is very low, or when fresh fuel has been thrown on, the temperature is a minimum and reaches a maximum again when the fresh fuel commences to burn fiercely. This constant expansion and contraction is found in practice to also so weaken the tube that it frequently collapses or is pressed together, resulting in great disaster. This led to the production and adoption of the — Lancashire Boiler, contrived to remedy this inconvenience and also to attain a more perfect combustion, the arrange- ment of the furnaces of which is shown in fig. 1 9 and fig. 20. It will be observed that there are two internal furnaces in- stead of one, as in the Cornish type. These furnaces are some- times each continued as a separate flue to the other end of the boiler as shown in the cuts ; but as a rule they emerge into one internal flue. They are supposed to be fired alternately, and the smoke and unburned gases issuing from the fresh fuel are ignitod in the flue by the hot air proceeding from the other furnace, the fuel in which is in a state of incandescence. Thus all violent changes in the temperature are avoided, and the waste of fuel due to unburned gases is avoided, if the firing is properly conducted. The disadvantage of the Lancashire boiler is the difficulty of finding adequate room for the two furnaces without unduly in- 56 Maxims and Instructions. Maxims a7td Instrtictions. 57 THE GROWTH OF THE STEAM BOILER. creasing the diameter of the shell. Low furnaces are extremely unfavorable to complete combustion, the comparatively cold crown plates, when they are in contact with the water of the boiler, extinguishing the flames from the fuel, when they are jusfc formed, while the narrow space between the fuel and the crown does not admit the proper quantity of air being supplied above the fuel to complete the combustion of the gases, as they arise. On the other hand, though this boiler favors the formation of the smoke, it supplies the means of completing the com- bustion afterwards, as before ex- _ _ _ ■ plained, by means of the hot air ^^^J^J-^^SSY^^S^^'fJ'jA from the second furnace. ^ Another disadvantage is the danger of collapsing the internal flue already spoken of ; this is remedied by the introduction of what are called the galloway tubes, illustrated in the cut shown on this page, which is a cross section of the water tubes shown in Figs. 18 and 20. These tubes not only contribute to strengthen the flues but they add to the heating surface and greatly promote the circu- lation so important in the water space. Note. These descriptions and illustrations of the Lancashire boiler are of general value, owing to the fact that 7ery many exhaust- ive tests and experiments upon steam economy have been made and permanently recorded in connection with this form of steam generator. s^ Maxims and Instructions, THE GROWTH OF THE STEAM BOILER. In the Galloway form of boiler the flue is sustained and stiffened by the introduction of numerous conical tubes, flanged at the two ends and riveted across the flue. These tubes, a sketch of which are given in fig. 18 (a), are in free communication with the water of the boiler, and besides acting as stiffeners, they also serve to increase the heating surface and to promote circulation. Fig. 19. Fig. 20. The illustration (figs. 18, 19 and 20) give all the principal details of a Lancashire boiler fitted with Galloway tubes. Fig. 18 represents a longitudinal section and figs. 19 and 20 shows on a large scale an end view of the front of the boiler with its fittings and also a transverse section. The arrange- ment of the furnaces, flues, and the Galloway tubes is suf- ficiently obvious from the drawings. The usual length of these boilers is 27 feet, though they are occasionally made as short as 21 feet. The minimum diameter of the furnaces is 33 inches, and in order to contain these comfortably the diameter of the boiler should not be less than 7 feet. The ends of the boiler are flat, and are prevented from bulging outwards by being held in place by the furnaces and flues which stay the two ends to- gether and also by the so-called gusset stays e, e. In addition to the latter the flat ends of the boiler have longitudinal rods to tie them together; one of these is shown &t A, A, ilg. 18, Maxims and Instructions, j'p THE GROWTH OF THE STEAM BOILER. The steam is collected in the pipe 8, which is perforated all along the top so as to admit the steam and exclude the water spray which may rise to the surface during ebullition. The steam thence passes to the stop valve T outside the boiler and thence to the steam pipes to the engines. There are two safety valves on top of the boiler on B (fig. 18 ), being of the dead weight type described hereafter, and the other, C, being a so-called low water safety valve. It is attached by means of a lever and rod to the float F, which ordinarily rests on the surface of the water. When through any neglect, the water sinks below its proper level the float sinks also, caus- ing the valve to open, thus allowing steam to escape and giving an alarm. M is the manhole with its covering plate, which admits of access to the interior of the boiler and H is the mud hole by which the sediment which accumulates all along the bottom is raked out. Below the front end and underneath, the pipe and stay valve are shown, by which the boiler can be emptied or blown off. On the front of the boiler (fig 19) are shown, the pressure gauges, the water gauges and the furnace door ; K is the feed pipe \ R, R, 2, pipe and cock for blowing off steam. In the front of the setting are shown two iron doors by which access may be gained to the two lower external flues for cleaning pur- poses. In the Lancashire boiler it is considered advisable to take the products of combustion, after they leave the internal flues, along the bottom of the boiler, and then back to the chimney by the side. When this plan is adopted the bottom is kept hotter than would otherwise be the case, and circulation is promoted, which prevents the coldest water from accumulating at the bottom. The Galloway (or Lancashire"^ boiler is considered the most economical boiler used in England, and is being introduced into the United States with success. The long traverse of heat provided (three turns of about 27 feet each) contributes greatly to its efficiency. 6o Maxims and Instructions. THE GROWTH OF THE STEAM BOILER. It may be useful to add the following data relating to this approved steam generator, being the principal dimensions and other data of the boiler shown in fig. 18: Steam pressure, 75 lbs. per sq. inch. Length, 27 feet. Heating surface : Diameter, 7 feet. In furnace and flues 450 sq. feet. Weight, total, 15^ tons. In Galloway pipes, 30 ^' Shell plates, yV inch. In external flues, 370 '' Furnace diameter, 33 inches. Furnace Plates, f inch. 850 sq. feet. End plates, \ inch. Grate area, 33 sq. feet. We have thus detailed step by step the improvement of the steam boiler to a point where it is necessary to describe at length the locomotive, the marine, the horizontal tubular and the water tube boilers, which four forms comprehend ninety-nine out of one hundred steam generators in use in the civilized world at the present time. MARINE BOILEES. The boilers used on board steamships are of two principal types. The older sort used for steam of comparatively low temperature, viz. : up to 35 lbs. per square inch, is usually made of flat plates stayed together, after the manner of the exterior and interior fire boxes of a locomotive boiler. Medium high pressure marine boilers, constructed for steam of 60 to 150 lbs. per square inch, are circular or oval in cross section, and are fitted with round interior furnaces and flues like land boilers. There are many variations of marine boilers, adapted to suit special circumstances. Fig. 22 shows a front elevation and partial sections of a pair of such boilers and fig. 23 shows one of them in longitudinal vertical section. Maxims and Instructions. THE MARINE STEAM BOILER. Fig 22. 6k 62 Maxims and Instructions. THE MARINE STEAM BOILER. It will be seen from these drawings that there are three in- ternal cylindrical furnaces at each end of these boilers, making in all six furnaces per boiler. The firing takes place at both ends. The flame and hot gases from each furnace, after pass- ing over the bridge wall enter a flat-sided rectangular combus- tion chamber and then travel through tubes to the front up- take (^. e, the smoke bonnet or breaching), and so on to the chimney. The sides of the combustion chambers are stayed to each other and to the shell plate of the boiler; the tops are strengthened in the same manner as the crowns of locomotive boilers, and the flat plates of the boiler shell are stayed to- gether by means of long bolts, which can be lengthened up by means of nuts at their ends. Access is gained to the uptakes for purposes of cleaning, repairs of tubes, etc., by means of their doors on their fronts just above the furnace doors. The steam is collected in the large cylindrical receivers shown above each boiler. The material of construction is mild steel. The following are the principal dimensions and other particulars of one of these boilers: Length from front to back 20 feet. Diameter of shell, 15 feet 6 inches. Length of furnace, 6 feet 10 inches. Diameter of furnace, 3 feet 10 inches. Length of tubes, 6 feet 9 inches. Diameter of tubes, 3^ inches. No. of tubes, 516. Thickness of shell plates, \\, Thickness of tube plates, f . Grate area, 12 6^ square feet. Heating surface, 401 5 square feet. Steam pressure, 80 lbs. per sq. inch. Fig. 24 is a sketch of a modern marine boiler, which is only fired from one end, and is in consequence much shorter in proportion to its diameter than the type illustrated in figs. 22 and 23. Maxims and InstrMctions, 63 THE MARINE STEAM BOILER. Marine boilers over nine feet in diameter have generally two furnaces, those over 13 to 14 feet, three, while the very largest boilers used on first-class mail steamers, and which often exceed fifteen feet in diameter, have four furnaces. In the marine boiler the course taken by the products of combus- tion is as follows; the coal enters through the furnace doors on to the fire-bars, the heat and flames pass over the fire bridge into the flame or combustion chamber, thence through the tubes into the smoke-box, up the up-take and funnel into the air. The fittings to a marine boiler are — funnel and. air casings, up- takes and air casings, smoke Fig. 24. boxes and doors, fire doors, bars, bridges, and bearers, main steam stop valve, donkey valve, safety valves and drain pipes, main and donkey feed check valves, blow-off and scum cocks, water gauge glasses on front and back of boiler, test water cock for trying density of water, steam cock for whistle, and another for winches on deck. A fitting, called a blast pipe, is sometimes placed in the throat of the funnel. It consists of a wrought iron pipe, hav- ing a conical nozzle within the funnel pointing upwards, the other end being connected to a cock, which latter is bolted on to the steam space or dome of the boiler. It is used for increasing the intensity of the draft, the upward current of steam forcing the air out of the funnel at a great velocity; and the air having to be replaced by a fresh supply through the ash-pits and bars of the furnaces, a greater speed of combus- tion is obtained than would otherwise be due to simple draft alone. ^4 Maxims and Instriictions^ THE MARINE STEAM BOILER. Boilers are fitted with dry and wet uptakes, which differ from each other as follows: — The dry uptake is wholly outside the boiler, and consists of an external casing bolted on to the firing end of the boiler, covering the tubes and forming the smoke-box, and is fitted with suitable tube doors. A wet up- take is carried back from the firing ends of the boiler into its steam space, and is wholly surrounded by water and steam. The dry uptake seldom requires serious repair; but the wet uptake, owing to its exposure to pressure, steam, and water, requires constant attention and repair, and is very liable to corrosion, being constantly wetted and dried in the neighbor- hood of the water-line. The narrow water space between both front uptakes is also very liable to become burnt, owing to accumulation of salt. The flue boilers of many tugs and ferry boats are fitted with wet uptakes. A superheater is a vessel usually placed in the uptake, or at the base of the funnel of a marine boiler, and so arranged that the waste heat from the furnaces shall pass around and through it prior to escaping up the chimney. It is used for drying or heating the steam from the main boiler before it enters the steam pipes to the engine. The simplest form of superheater consists of a wrought iron drum filled with tubes. The heat or flame passes through the tubes and around the shell of the drum, the steam being inside the drum. Superheaters are usually fitted with a stop valve in connection with the boiler, by means of which it can be shut off; and also one to the steam pipe of the engine; arrangements are also usually made for mixing the steam or working independently of the superheater. A safety valve is also fitted and a guage glass; the latter is to show whether the superheater is clear of water, as priming will sometimes fill it up. The special fittings of the marine boiler will be more partic- ularly described hereafter as well as the stays, riveting, strength, etc., etc. Maxims and Instructions. 65 THE MARINE BOILER. The nse of the surface condenser in connection with the marine boiler was an immense step toward increasing its effi- ciency. In 1840 the average pressure used in marine boilers was only 7 or 8 lbs. to the square inch, the steam being made with the two-flue pattern of boiler, sea water being used for feed ; as the steam pressure increased as now to 150 to 200 lbs. to the square inch, greater and greater difficulty was experi- enced from salt incrustation — in many cases the tubes did not last long and frequently gave much trouble, until the intro- duction of the surface condenser, which supplied fresh water \o the boilers. b^/UmA Vlaltr from CirtulaCuig hunfi Fig. 25. The Surface Cokdbnsbb. The condenser is an oblong or circular box of cast iron fitted in one of two ways, either with the tubes horizontal or vertical: at each end are fixed the tube plates, generally made of brass, and the tubes pass through the plates as well as through a supporting plate in the middle of the condenser. Each end of the condenser is fitted with doors for the purpose of enabling the tube ends to be examined, drawn, or packed, as may be necessary. The tube ends are packed in various ways, and the tubes are made of brass, so as to resist the action of the w^ter. The water is generally sucked through the tubes bj 66 Maxims and Instructions^, TF^ CONDENSER. the circulating pump, and the steam is condensed by coming in contact with the external surface of the tubes. In some cases the water is applied to the external surface, and the steam exhausted through the tubes ; but this practice is now generally given up in modern surface condensers. The pack- ing round the tube ends keeps them quite tight, and in the event of a split tube, a wooden plug is put in each end until an opportunity offers for drawing it and replacing with a new one. The condenser may be made of any convenient shape. It sometimes forms part of the casting supporting the cylinders of vertical engines ; it is also frequently made cylindrical with flat ends, as in fig 25. The ends form the tube plates to which the tubes are secured. The tubes are, of course, open at the ends, and a space is left between the tube plate and the outer covers, shown at each end of the condenser, to allow of the circulation of water as shown by the arrows. OPERATIOiir OF THE COKDEKSER. The cold water, which is forced through by a circulating pump, enters at the bottom, and is compelled to pass forward through the lower set of tubes by a horizontal dividing plate ; it then returns through the upper rows of tubes and passes out at the overflow ; the tubes are thus maintained at a low tem- perature. The tubes are made to pass right through the condensing chamber, and so as to have no connection with its internal space. The steam is passed into the condenser and there comes in contact with the cold external surface of the tube, and is condensed, and removed, as before, by the air pump, as may be readily seen in the illustration (p. 65). The advantages gained by the use of the surface condenser are : 1. The feed water is hotter and fresh ; being hotter, it saves the fuel that would be used to bring it up to this heat; and being fresh, it boils at a lower temperature. 2. Not term- ing so m-uch scale inside the boiler, the heat passes through to the water more readily ; and as the scum cock is not used so freely, all the heat that would have been blown off is saved. Its disadvantages are that being fresh water and toj*ming no scq-le on the boiler, it causes the boiler to 10^^ Maxims and Instructions. 67 THE MARINE BOILER. is often said that one engineer will get more out of a It ship than another. In general it will be found that the most successful engineer is the man who manages his stokers best. It is very difficult on paper to define what is meant. It is a thing to be felt or seen, not described. * * * * The engineer who really knows his business will give his fires a fair chance to get away. He will work his engines up by degrees and run a little slowly for the first few moments. WATER TUBE STEAM BOILERS. A popular form of steam boiler in use in the United States and Europe is what is called the water tube boiler. This term is applied to a class of boiler in which the water is con- tained in a series of tubes, of comparatively small diameter, which communicate with each other and with a common Water Tube Boiler.— Fig. 26. steam-chamber. The flames and hot gases circulate between the tubes and are usually guided by partitions so as to act equally on all portions of the tubes. There are many varieties of this type of boiler of which the cut illustrates one : in this each tube is secured at either end into a square cast-iron head, and each of these heads has two openings, one communicating with the tube below and the other with the tube above \ the 68 Maxims and Instruclzons. WATER TUBE STEAM BOILERS. communication is effected by means of hollow cast-iron caps shown at the end of the tubes ; the caps have openings in them corresponding with the openings in the tube heads to which they are bolted. In the best forms of the water tube boilers, it is suspended entirely independent of the brick work from wrought iron girders resting on iron columns. This avoids any straining of the boiler from unequal expansion between it and its enclosing walls and permits the brick work to be repaired or removed, if necessary, without in any way disturbing the boiler This design is shown in Fig. 26. The distinguishing difference, which marks the water tube boiler from others, consists in the fact that in the form^er the small tubes are filled with water instead of the products of combus- tions ; hence the comparison, frequently made, between water- tube and^re tuhe boilers— the difference has been expressed in another way, '' Water-tube vs. shell boilers, ^^ but the principle of steam production in both systems remains the same ; the heat from the combustible is transferred to the water through the medium of iron plates and in both, the furnaces, steam appliances, application of the draught, etc., is substantially the same. In another important point do the systems agree, i, e., in the average number of pounds of water evaporated per lb. of combustible ; it is in the thoroughness of construction and skillfulness of adaptation to surroundings that produce the best results. Water tube or sectional boilers, have been made since the days of James Watt, in 1766, in many different forms and under various names. Owing, however, to the imperfec- tion of manufacture the system, as compared to shell boilers, has been a failure until very recently; various patterns of water-tube boilers are now in most favorable and satisfactory use. The advantages claimed for this form of steam generator are as follows : 1. Safety from disastrous explosions, arising from the division of the contents into small portions, and especially from details of construction which make it tolerably certain that the rupture will be local instead of a general violent ex- plosion which liberates at once large masses of steam aiid water. Maxims and Instruct ions, 6p WATER TUBE STEAM BOILERS. 2. The small diameter of the tubes of "v^hich they are com- posed render them much stronger than ordinary boilers. 3. They can be cheaply built and easily repaired, as duplicate pieces can be kept on hand. The various parts of a boiler can be transported without great expense, trouble or delay ; the form and proportions of a boiler can be suited to any available space ; and, again, the power can be increased by simply ad- ding more rows of tubes and increasing the grate area. 4. Their evaporative efficiency can be made equal to that of other boilers, and, in fact, for equal proportions of heating and grate surfaces, it is often a trifle higher. 5. Thin heating surface in the furnace, avoiding the thick plates necessarily used in ordinary boilers which not only hinder the transmission of heat to the water, but admit of overheating, 6. Joints removed from the fire. The use of lap welded water tubes with their joints removed from the fire also avoid the unequal expansion of riveted joints consequent upon their doable thickness. 7. Quick steaming. 8. Accessibility for cleaning. 9. Ease of handling and erecting. 10. Economy and speediness of repairs. The known disadvantages of these boilers are • 1. They generally occupy more space and require more masonry than ordinary boilers. 2. On account of the small quantity of water which they contain, sudden fluctuations of pressure are caused by any irregularities in supplying the feed-water or in handling the fires, and the rapid and at times violent generation of steam causes it to accumulate in the contracted water-cha^lbers, and leads to priming, with a consequent loss of water, and to over- heated tubes. 7^ Maxims and Instructions, WATER TUBE STEAM BOILERS. 3. The horizontal or inclined water tubes which mainly compose these boilers, do not afford a ready outlet for the steam generated in them. The steam bubbles cannot follow their natural tendency and rise directly, but are generally obliged by friction to traverse the tube slowly, and at times the accumulation of steam at the heated surfaces causes the tubes to be split or burned. 4. The use of water which forms deposits of solid matter still further increases the liability to overheating of the tubes. It has been claimed by some inventors that the rapid circulation of the water through the tubes would prevent any deposit of scale or sediment in them, but experience has proved this to be a grave error. Others have said that the expansion of the tube would detach the scale as fast as it was deposited and prevent any dangerous accumulation, but this also has been proved an error. Again, the use of cast iron about these boilers has frequently been a constant source of trouble from cracks, etc. CARE OF WATER TUBE BOILERS. The soot and ashes collect on the exterior of the tubes in this form of boilers, instead of inside the tubes, as in the tubular, and they must be as carefully removed in one case as in the other; this can be done by the use of blowing pipe and hose through openings left in the brick work ; in using bituminous coal the soot should be brushed off when steam is down. All the inside and "outside surfaces should be kept clean to avoid waste of fuel ; to aid in this service the best forms are provided with extra facilities for cleaning. For inspection, remove the hand holes at both ends of the tubes, and by hold- ing a lamp at one end and looking in at the other the condition of the surface can be freely seen. Push the scraper through the tube to remove sediment, or if the scale is hard, use tl'o chipping scraper made for that purpose. Hand holes should be frequently removed and surfaces examined, particularly in case of a new boiler. In replacing Maxims and Instructions. 7/ CAEE OF WATER TUBE BoIlERS. hand hole caps, clean the surfaces without scratching or bruising, smear with oil and screw up tight. The mud drum should be periodically examined and the sediment removed ; blow-off cocks and check valves should be examined each time the boiler is cleaned ; when surface blow- cocks are used they should be often opened for a few minutes at a time ; be sure that all openings for air to boiler or flues except through the fire, are carefully stopped. If a boiler is not required for some time, empty and dry it thoroughly. If this is impracticable, fill it quite full of water and put in a quantity of washing soda; and external parts exposed to dampness should receive a coating of linseed oil. Avoid all dampness in 8eatings or coverings and see that no water comes in contact with the boiler from any cause. Although this form of boiler is not liable to destructive explosion, the same care «hould be exercised to avoid possible damage to boilers and expensive delays. SECTIONAL BOILERS. Probably one of the first sectional boilers brought into practical use is one made of hollow cast iron spheres, each 8 inches in diameter, externally, and f of an inch thick, connected by curved necks 3i inch in diameter. These spheres are held together by wrought iron bolts and caps, and in one direction are cast in sets of 2 or 4, which are afterwards drawn together so as to give more or less heating surface to the boiler according to the number used. NOTE. Owing to their multiplication of parts all sectional, including water tube boilers, should be made with unusual care in their details of construction, setting, fittings and proportions. It is to the attention paid to these '' points " that the sectional boilers are now coming into more general favor. ^2 Maxims and Instructions, LOCOMOTIVE BOILEES. The essential features of locomotive boilers are dictated by the duties which they have to perform under peculiar condi- tions. The size and the weight are limited by the fact that the boiler has to be transported rapidly from place to place, and also that it has to fit in between the frames of the locomotive ; while at the same time, the pressure of the steam has to be very great in order that with comparatively small cylinder the engine may develop great power ; moreover, the quantity of water which has to be evaporated in a given time is very con- siderable. To fulfil these latter conditions a large quantity of coal must be burned on a fire grate of limited area ; hence in- tense combustion is necessary under a forced blast. To utilize advantageously the heat thus generated, a large heating surface must be provided and this can only be obtained by passing the products of combustion through a great number of tubes of small diameter. The forced draught in a locomotive boiler is obtained by causing the steam from the cylinders, after it has done its work to be discharged into the chimney by means of a pipe called the blast pipe ; the lower portion of this consists of two branches, one in communication with the exhaust port of each cylinder. As each puff of steam from the blast pipe escapes up the chimney it forces the air out in front of it, causing a partial vacuum, which can only be supplied by the air rushing through the furnace and tubes. The greater the body of steam escaping at each puff, and the more rapid the succession of puffs, the more violent is the action of the blast pipe in producing a draught, and conse- quently this contrivance regulates the consumption of fuel and the evaporation of water to a certain extent automatically, because when the engine is working its hardest and using the most steam, the blast is at the same time most efficacious. The blast pipe is, perhaps, the most distinctive feature of the locomotive boiler, and the one which has alone rendered it possible to obtain large quantities of steam from so small a Maxims and Instructions, 13 74 Maxims and Instructions, THE LOCOMOTIVE BOILER. generator. The steam blast of the locomotive has been com- pared to the breathing apparatus of a man, and has rendered the mechanism described nearer a live thing than any other device man has ever produced. On account of the oscillations, or violent motions to which the boiler of locomotive engines are subject, weighted safety valves are not possible to be used and springs are used instead to hold the valves in j^lace. The locomotive form of steam boiler is sometimes used for stationary engines, but owing to extra cost and increased liability to corrode in the smaller passage they are not favorites. DESCRIPTIOK OF PAGE ILLUSTRATION. In fig. 27, FB represents the fire box or furnace; F D, fire door ; D P, deflector plate ; F T P, fire box tube plate ; t" B R S, fire box roof stays ; S T P. smoke box tube plate ; S B, smoke box ; S B D, smoke box door ; S D, steam dome ; S, outer shell ; R S V", Ramsbottom safety valve ; F, funnel or chimney. ' !! 1 1 1 1 I : - 1 1 ' i 1 1 : • i 1 II o^^ The crown plate of the fire-box being flat reqiures to be efficiently stayed, and for this purpose girder stays called fox roof stays are mostly used, as shown in the figure. The stays are now made of cast steel for locomotives. They rest at the two ends on the vertical plates of the fire-box, and sustain the Maxims and Inslructtons. 75 THE LOCOMOTIVE BOILER. pressure on the fire-box crown by a series of bolts passing througli the plate and girder stay, secured by nnts and washers. Fig. 28 is a plan and elevation of a wrought-iron roof stay. Another method adopted in locomotive types of marine boilers for staying the flat crown of the fire-box to the circular upper plate is shown in fig. 29— namely, by wrought-iron vertical bar stays secured by nuts and washers to the fire-box with a fork end and pin to angle-iron pieces riveted to the boiler shell. A^ Q Q ^ =Wt The letters in this figure refer to the same parts of the boiler as do those in fig. 27, i.e., F B to the fire-box, etc., etc. It was formerly the custom to make the tubes much longer than shown in the fig., with the object of gaining heating surface ; but modern experience has shown that the last three or four feet next the smoke box were of little or no use, because, by the time the products of combustion reached this part of the heating surface, their temperature was so reduced that but little additional heat could be abstracted from them. The tubes, in addition to acting as flues and heating surface, fulfil also the function of stays to the flat end of the barrel of the boiler, and the portion of the fire box opposite to it. ' In addition to the staying power derived from the tubes, the smoke box, tube plate and the front shell plate are stayed together by several long rods. 76 Maxims and InstrMctions, ^ M o PQ < t» pq <1 H "A o tSJ M o Maxims and Instructions, STANDARD HORIZONTAL TUBULAR STEAM BOILER. TABLE OF SIZES, PROPOETIOlirS, ETC. 5 °,d mber of abes. ©<^, © W uare et of ating rface. s ^ - «. ^ m o W ^ ^ H ^ B *«w^ ^w^ 72 in. 19 ft. 4 in. 3-8 in. 1-2 in. 80 4 in. 18 ft. Oin. 1,500 100 72 " 18** 4" 3-8 ** 1-2 ** 86 8* o3 DIAMETER OF BRACR Tensue strength per •quare inch of section allowed r r 2208 2650 3092 3313 1" 3006 3607 4209 4509 1" 3927 4712 5497 5890 H" 4970 5964 6958 7455 6136 7363 8590 9204 8835 10602 12369 13253 12026 14431 16837 18039 r 6000 6000 7000 7500 981 1178 1874 1472 1533 1840 5567 2750 15708 18849 21991 23562 Shop Names foe Boiler Braces. — 1. Gusset brace (fig. 47). 9. Crowfoot brace. 3. Jaw brace (fig. 44). 4. Head to head brace (fig. 60). These shop terms refer to braces used in the tubular form of boiler. A Stat a:n^d a Brace in a steam boiler fulfil the same office, that of withstanding the pressure exerted outward of the ex- panded and elastic steam. Socket Bolts are frequently used instead of the screw stay between the inside and outside plates that form the center space. Socket bolts are driven hot the same as rivets. The method of bracing with X ^a-rs is considered the best; the bars make the flat surface rigid and unyielding even before the brace is applied. The braces should be spaced about 8 inches apart on the X ^^^^ ^^^ ^ inches from the edge of the flange X ^'^ ^^^^ should be 4" X ^"\" X iron and riveted to the head or flat surface with ^" rivets spaced 4^ inches apart. Hollow Stay Bolts are used in the side of locomotive boil- ers at the top of the fire line, to aid the combustion; these are ordinarily \\" in diameter. The flange of a boiler head ^ thick will amply support 6 inches from the edge of the flange. A radius of 2 inches is ample for bend of flange on the head. The lower braces should be started 6 inches above the top row of tubes. Braces should be fitted so as to have a straight pull, t. e, parallel with the boiler shell. The heads of the boiler should be perfectly straight before the braces are fitted in place. Gusset brace plates should not be less than 30 inches long and 14 inches wide. Braces are best made of 1 inch O iron of highest efficacy with tensile strength of not less than 68,000 lbs. to the square inch. t04 Maxims and Instructions. POINTS RELATING TO BOILER BRACES. I I Fig. 51 i The riyeted stay shown in Fig. 51, consists of a long rivet, passed through a thimble or distance piece of wrought iron pipe placed between plates, to be stayed together, and then riveted over in the usual man- ner. An ingenious device is in use to show when a bolt has broken. A small hole is drilled into the head, extending a little way beyond the plate, and as experience shows that the fracture nearly always occurs next to the outside plate, that is the end taken for the bored out head: when the bolt is broken the rush of steam through the small hole shows the danger without causing serious disturbance. Even where the best of iron is used for stay bolts they should never be exposed to more than 117th or iVth their breaking strength. The stays should be well fitted, and each one carefully tight- ened, and, as far as possible each stay in a group should have the same regular strain upon it — if the " pull " all should come on one the whole are liable to give way. DiMEiirsiOKS AiTD Shape of Angle and T Ieok. ANCLE IRON. ^^ ""''*• Fig. 63. Maxims and Instructions. foS POINTS RELATING TO BOILER BRACES. The condition of a boiler can be learned by tapping on the sheets, rivets, seams, etc., to ascertain whether there are any broken stays, laminated places, broken rivets, etc. Big. A. Big. B. Fig. A represents the method of preparing testing pieces of boiler plate, for the machines prepared specially to measure their elongation before breaking, and also the number of pounds they will bear stretching before giving way. Fig. B exhibits the same with reference to the brace and other O '^^'^ RULES AND TABLES FOR DETERMINING AREAS AND CALCULATING THE CONTENTS OP STEAM AND WATER SPACES IK THE STEAM BOILER.* To make these calculations, a circle should be drawn repre- senting the circumference of the head of the boiler, and a line drawn across between points, corresponding with the ends of the upper row of tubes. Measure carefully that portion of the circle which is above these points which are represented by the figure in the diagrams and D, and multiply it by one-quar- ter of the diameter of the circle. Then measure the length of the line 1, 2, multiply it by one-half of the dotted line drawn from the center of the circle to the base of the segment, and Bubtract this product from the result first obtained. The re- mainder will be the area of the segment. *We are indebted to W. H. Wakeman, M. E., for this mla. ro6 Maxims and Instructions, STEAM AND WATER SPACES. Fig. C. Fig. D. Suppose the circle to be forty- eiglit inches in diameter a.d the segment fourteen inches high, the upper part of the cucie between 1 and 2 will measure four feet six inches, or in evact figures, 54.6875 inches; one-quarter of the diameter of the circle is 12 inchesand 54.6875 x;i2=656.35. The straight hne, from 1 to 2, we' find to be, say, 4S 75 inches m length, the line extending from the center of tJie circle to the segment base is 10 inches long, half of this is 5.0x43.75=218.75. 656—218.75=437.5, the area in square inches of the segment. To find the area of the larger portion of the circle, the lengtk of the line from 1 to 2 must be carefully ascertained and mul- tiplied by one-fourth the diameter of the circle. Half the length of the straight line from 1 to 2 must then be multiplied by one-half the dotted line, the product added to the figures already obtained, and the result will be the area of the larger portion of the circle. Special care must be bestowed on the measurement of the curved lines, as a mistake of a fraction of an inch will throw the calculations out. For the following valuable tables we are indebted to success- ive numbers of that unique and instructive journal, the LocO' motive. Maxims and Instructions. toy TABLES FOR CALCULATING NUMBER OF STAYS. The accompanying tables will greatly facilitate the calcu- lation of the number of braces required in a boiler that is to run under any given pressure. They contain the results of long experience on the subject, and can be relied upon to give perfectly satisfactory results. It has teen shown hy direct experiment that the tubes pos- sess sufficient holding power to amply stay the part of the head to which they are attached, and we may safely consider that they will also possess sufficient staying power to take care of the head /or two {2) inches above their upper surfaces. The flanges of the heads being securely united to the shell, and being also curved or dished, it may likewise be safely as- sumed that no braces need be provided for thai 'part of the head which lies ivithin three (3) inches of the shell. The part to be braced, therefore, consists of a segment of a circle whose cir- cumference lies three inches within the circle of the shell, and whose base is two inches above the upper row of tubes. Thus in a 66-inch boiler, whose upper row of tubes is 26 inches below the top of the shell, the part of the head that requires bracing consists in a segment of a circle, the diameter of which is 60 inches, and the height of which is 21 inches ; 21 inches being the measured height (26 in.), minus the 3 inches that lies between the shell and the segment to be braced, and minus the two inches that lies between this segment and the top of the tubes. Table No. 1 gives the total area in square inches. No. 2, areas to be braced. No. 3, number of braces of one inch round iron required, allowing sefen thousand five hundred pounds per square inch of section at one hundred pounds steam pressure. Table 3 will be found of more practical use than Table 2, for it gives directly the number of braces required in any given boiler, instead of the area to be braced. It was calcu- lated from Table 2. The iron used in braces will safely stand io8 Maxims and Instructions^ TABLES FOR CALCULATING NUMBER OF STAYS. a continiious pull of 7:,500 pounds to the square inch, whicb, is the figure used in computing the foregoing table. A round brace an inch in diameter has a sectional area of .7854- of an inch, and the strain that it will safely withstand is found by multiplying .7854 by 7,500, which gives 5,890 pounds as the safe working strain on a brace of one-inch round iron. In a 60-inch boiler, whose upper tubes are 28 inches be- low the shell, the . area to be braced is, according to table, ^,930 square inches. If the pressure at which it is to be run is 100 pounds to the square inch, the entire pressure on the area to be braced will be 93,000 pounds, and this is the strain that must be withstood by the braces. As one brace of inch-round iron will safely stand 5,890 pounds, the boilei will need as many braces as 5,890 is contained in 93,000, which is 15.8. That is, 16 braces will be required. The table is made out on the basis of 100 lbs. pressure to the square inch, because that is a very convenient number. Table No. 1. TOTAL AREA ABOVE TUBES OR FLUES. (Square Inches.) DIAMETER OF BOILER IN INCHES. Height from Height from tubes to shell. 36 43 48 54 60 66 72 tubes to shell. 15 389 15 16 419 16 17 458 526 17 18 566 620 667 18 19 608 667 720 19 20 650 714 770 824 20 21 756 824 882 21 22 808 878 937 22 23 930 996 1059 23 24 982 1056 1121 24 25 1037 1116 1184 25 26 1090 1209 1252 1324 26 27 1145 1234 1316 1394 27 28 1391 1381 1465 28 29 1352 1445 1536 29 30 1414 1511 1608 30 31 1576 1674 31 32 1641 1746 32 83 1818 33 84 1896 34 Maxims and Instructions. log TABLES FOR CALCULATING NUMBER OF BRACES. Table 3. AREAS TO BE BRACED (Square Inches.) Height from DIAMETER OF BOILER IN INCHES. Height trom tubes to tubes to Bhell. 86 42 48 fA 60 66 72 shell. 15 206 15 16 235 16 17 264 297 17 18 831 365 896 18 19 816 404 439 19 20 401 444 483 619 20 21 485 528 568 21 88 626 574 618 22 23 620 668 714 28 24 667 720 769 24 25 714 772 825 26 26 761 824 883 087 26 27 809 877 940 998 27 28 930 998 1061 28 29 983 1056 1124 29 80 1037 1115 1187 80 81 1174 1252 81 82 1334 1317 82 83 1383 83 84 1447 84 Table 8. NUMBER OF BRACES REQUIRED, AT 100 LBS. PRESSURE. DIAMETER OF BOILER IN INCHES. Height from Hfiipht fr^IB tubes to tubes to shelL 86 4a 48 64 60 00 T8 BhelL 16 8.5 15 16 4.0 16 17 4.5 5 17 18 5.6 6.2 6.7 18 19 6.3 6.9 7.5 19 20 6.8 7.5 8.3 8.9 20 21 8.2 9.0 9.6 21 23 8.9 9.8 10.5 23 23 10.5 11 3 13.1 23 24 11.3 12.3 13.1 24 26 13.1 13.1 14.0 25 26 12.9 14.0 15.0 16.9 26 27 13.7 14.9 16.0 16.9 27 28 15.8 16.9 18.0 28 29 16.7 17.9 19.1 89 80 17 6 18.9 20.3 80 31 19.9 21.3 81 83 21.0 22.4 83 83 23.5 8f 84 A ' 84 JIO Maxims and Instructions, BOILER TUBES. In Table 2 this calculation has been made for all sizes of boilers that are ordinarily met with. The area to be braced has been calculated as above in each case, the two-inch strip aboYG the tubes, and the three-inch strip around the shell be- ing taken into account. As an example of its use, let us suppose that upon measuring a boiler we find that its diam- eter is 54 inches, and that the distance from the upper tubes to the top of the shell is 25 inches. Then by looking in the table under 54" and opposite 25" we find 714, which is the number of square inches that requires staying on each head. BOILER TUBES. Table. Dimensions of Lap Welded Boiler Tubes, Size outside diajneter. Wire Guage. Weight per foot. Size outside j diameter. Wire Gauge. Weight per foot. 1 inch. 15 0.708 31- inches. 11 4.272 li '' 15 0.9 ,3f - 11 4.590 H '' 14 1.250 ;4 10 5.320 If - 13 1.665 ki - 10 6.010 2 " 13 1.981 5 9 7.226 2i ^' 13 2.238 6 8 9.346 2i- 12 2.755 7 8 12.435 2f - 12 3.045 8 8 15.109 3 '' 12 3.333 9 n 3i - 11 3.958 10 '' 64 The above is the regular manufacturers' list of sizes and weights. Note* Boiler tubes are listed and described from the outside diame- ter. This should be noted, as gas- pipe is described from the inside diameter. Thus a 1-inch gas-pipe is nearly 1^ outside diameter while a 1-inch boiler tube is exactly one inch. Another difference between the two consists in the fact that the outside of boiler tubes is rolled smooth and eyen, gas-pipe is left com- paratively rough and uneven. Maxims and Instructions. Hi BOILER TUBES. When the boiler tubes are new and properly expanded there is a large reserve or surplus of holding power for that part of the tube sheet supported by them, this has been proved by ex- periment made by chief engineer W. H. Stock, U. S. N. as shown in the following Table of Holdikg Power of Boiler Tubes. 0« «M Inches. 2t 2t o-2o (U Of PJ M CDT3 < 9, Sq. ins. .981 .981 .981 .981 .981 PI Pt Indies. tV o Pt Pounds. 22650 22150 25526 29675 13050 Metliod of Fastening. Expanded by Dudgeon tool, end riveted over. Expanded by Dudgeon tool, end partly riveted over. Expanded by Dudgeon tool, end riveted over. Expanded by Dudgeon tool, fer- ruled, not ri v^eted over. Simply expanded by Dudgeon tool. Mr. C. B. Eichards, consulting engineer at Colt's Armory at Hartford, Conn., made some experiments as to the holding power of tubes in steam boilers, with the following results: The tubes were 3 inches in external diameter, and 0.109 of an inch thick, simply expanded into a sheet f of an inch thick by a Dudgeon expander. The greatest stress without the tubes yielding in the plate was 4,500 pounds, and at 5,000 pounds was drawn from the sheet. These experiments were repeated with tbe ends of the tubes which projected through the sheet three-sixteenths of an inch, being flared so that the external diameter in the sheet was expanded to 3.1 inches. The great- est stress without yielding was 18,500 pounds ; at 19,000 pounds yielding was observed ;and at 19,500 pounds it was drawn from the sheet. The force was applied paralled to the axis of the tube, and the sheet surfaces were held at right angles to the ^be axis. tI2 Maxims and Instructions, BOILER TUBES. Note. Wlien the tube sheet and tube ends near the the sheet become coated with scale or the tubes become over heated, the holding power of the tubes becomes largely reduced and caution must be used in having the tube ends re-expanded and accumulated scale removed. Note. 2 — In considering the stress or strain, upon the expan- ded or riveted over ends of a set of boiler tubes it may be re- membered that the strain to be provided against is only that coming upon tube plate, exposed to pressure, between the tube ends — ^the space occupied by the tubes has no strain upon it. The gauge to be employed by inspectors to determine the thickness of boiler plates, will be any standard American gauge furnished by the Treasury Department. All samples intended to be tested on the Eiehle, Fairbanks, Olsen, or other reliable testing machine, must be prepared in form according to the following diagram, viz: eight inches in length, two inches in width, cut out at their centers as indica- ted. Fig. E. Portions of the Marine Boiler which Become Thin BY Wear. These are generally situated, 1st, at or a little above the line of fire bars in the furnace; 2d, the ash pits; 3d, combustion chamber backs; 4th, shell at water line; 5th, front and bottom of boiler. The thinning can usually be detected by examination, sound- ing with a round nosed hammer, or drilling small holes in inspected parts not otherwise accessible for e:3^aminatio4. Maxims and Instrtutiom. "3 EXAMPLES OF CONSTRUCTION AND DRAWING The small table at the left is of use in this and the four succeeding pages ; in all places in the drawings where '' d" is used it indi- cates tlie diameter of the rivet; /'t" means the tUchness of the plate; *'p" stauds for pitch. The table also shows the proportion of rivet to the plate— thus, a J inch plate requires a h rivet, etc. It is recommended, in view of the in- creased disposition on the part of official examiners to test the applicant's knowledge of drawing, for any one interested , to redraw to afv.ll size all the rivets, plates, and methods of join- ing the two contained on pages 113-116. «r # ^ t fA ^4 % s/i ^>/>s S//6 yy/6 ^/^ 'A: j/s /Vi9 r/? ^_ J^ ^'/J6 d = DIAM. OF RIVET. e=THICKNESS OF PLATE. Kg. sa PAN HEAO Fig. 54. The figures 53 to 60 will be understood without much expla- nation. In figures 53 and 54 the cup heady the conical head and pan head rivets are shown. Figs. 55 and 56 exhibit the details (and drawings) of single and double riveting. Where the cut reads p=2|d, it means that that the distance from the center of one rivet to the cen- ter of the next shall be 2|- the diameter of the rivet, see ex- ample, page 115. 114 Maxims and Instructions. CONSTRUCTION AND DRAWING. Fig. 65. Fig, 66, Maxims and InstrucHons* '^5 CONSTRUCTION AND DRAWING. Example. If tlie size of the rivet used is fths, then f X2J=2A inches nearly, and this gives the proportionate strength of the plate and the rivet, see page 113. COMBINED LAP AHD m},m, , , . ,^ GOWPLETE THE PLAN. ^../i^/^. I ^^^^ .....^.^. .v^i -xf <^ )^os'r-ico»ot-THco»05005'-'CC»ot' of Plates OiOJOJCQCQCOCOCC WC^C^JC^JC^COCOCOCOOiOiG^CQO^COCOCOOO I ©l^ CO OOCO — ' 00 L^ O «2 XCiCiClCS'J^OOCSOOOSWlOCQCOCOOSWOS !2^COaO-*CQ-TOv/sO C:CiCSC505t-CJCS'^ Cilr.-'OCOCOOiOSOOOS • ^ *; cc 00 '^ cvJ L-5 :o '>\ — :c o ^ — '" ci cad o '*' ci oi co o cc c6 cx5 cs cc oi ^ T;.^ .-- O O LO CJ 00 X) O rt- r- X «0 t-i C^_ ^ r- i- O t- X ^_ tH O CO ^ 00 '"' I a 5 :£ cj cCO^Lt:!DXCSO— --'0>CO^!Ot-XC50 I ©l? lO CS 1^ ?> ?t CO O 03 'X C5 C5 C; C5 O? X CS^ 35XU0'^CQ^!>O'<:i< '^ -:*^ L? ■ 5 S -^ «D O r-^ 05 X' C3 T-! 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The definitions necessary are, then, briefly as follows : — Tensile Strength is equivalent to the amount of force which, steadily and slowly applied in a line with the axis of the test piece, just overcomes the cohesion of the particles, and pulls it into separate parts. Contraction of Area is the amount by which the area, at the point where the specimen has broken, is reduced below what it was before any strain or pulling force was applied. Elongation is the amount to which the specimen stretches, between two fixed points, due to a steady and slowly applied force, which pulls and separates it into parts. Elongation is made up of two parts ; one due to the general stretch, more or less, over the length ; the other, due to contraction of area at about the point of fracture. Shearing" strength is equivalent to the force which, if steadily and slowly applied at right angles, or nearly so, to the line of axis of the rivet, causes it to separate into parts, which slide over each other, the planes of the surface at the point of separation being at right angles, or nearly so, to the axis of the rivet. Elastic limit is the point where the addition to the per- manent set produced by each equal increment of load or force, steadily and slowly applied, ceases to be fairly uniform, and is suddenly, after the point is reached, increased in amount. It is expressed as a percentage of the tensile strength. Tongh. — The material is said to be " tough" when it can be bent first in one direction, then in the other, without frac- turing. The greater the angles it bends through (coupled with the number of time it bends), the tougher it is. Dnctile. — The material is *' ductile '* when it can be ex- tended by a pulling or tensile force and remain extended after the force is removed. The greater the permanent extension, the more ductile the material. /^^ Maxims and Instructions. DEFINITION OF TERMS. Elasticity is that quality in a material by which, after be- ing stretched or compressed by force, it apparently regains its original dimensions when the force is removed. Fatigued is a term applied to the mate] ial when it has lost in some degi'ee its power of resistance to fracture, due to the repeated application of forces, more particularly when the forces or strains have varied considerable in amount. Malleable is a term applied to the material when it can be extended by hammering, roliing, or otherwise, without fractur- ing, and remains extended. The more it can be extended with- out being fractured, the more malleable it is. Weldable is a term applied to the material if it can be united, when hot, by hammering or pressing together the heated parts. The nearer the properties of the material, after being welded, are to what they were before being heated and welded, the more weldable it is. Cold-short is a name given to the material when it cannot be worked under the hammer or by rolling, or be bent when cold without cracking at the edges. Such a material may be worked or bent when at a great heat^ but not at any tempera- ture which is lower than about that assigned to dull red. Hot-short is when the material cannot be easily worked under the hammer, or by rolling at a red-heat at any tempera- ture which is higher than about that assigned to a red-heat, without fracturing or cracking. Such a material may be worked or bent at a less heat. Homogeneous describes a material which is all of the same structui*e and nature. A homogeneous material is the best for boilers, and it should be of suitable tensile strength with contraction of area and elongation best suited for the purpose, having an elastic limit that will insure the structure being reliable ; it should be tough and ductile, and its elasticity fairly good, and be capable of enduring strains without becoming too quickly or easily fatigued. The material should be malleable and in some cases weldable ; that which is of a decidedly cold-short or hot-short nature should be avoided. Maxims and InstrMctions. 123 BOILER KEPAIRS. 01 This cufc represents a form of clamp used in holding the plates against each other when being riyeted. Fig. 66. Fig. 67 represents a peculiar form of bolt for screw- ing a patch to a boiler. It is threaded into the boiler plate, the champer rests against the patch and the square is for the application of the wrench. After the bolt is well in place, the head can be cut off with a cold chisel. REPAIEINa CRACKS. Cracks in the crown-sheet or side of a fire-box boiler, or top head of the upright boiler can be temporarily repaired by a row of holes drilled and tapped touching one another, with f or -J inch copper plugs or bolts, screwed into the plates and after- wards all hammered together. For a permanent job, cut out the defect and rivet on a patch. This had better be put on the inside, so as to avoid a *' pocket '' for holding the dirt. In putting on all patches, the defective part must be entirely removed to the solid iron, especially when exposed to the fire. Note.— When fire comes to two surfaces of any consider- able extent, the plate next to the fire becomes red-hot and weakens, hence the inside plate, in repairs, must be removed. The application of steel patches to iron boilers is injudicious. Steel and iron differ structurally and in every other particular, and their expansion and contraction under the influence of changing temperatures, is such that trouble is sure to result from their combination. 1^4 Maxims and Instructions. DEFECTS AND NECESSARY REPAIRS. Fig. 68. heated and expanded tubes. Fig. 68 represents a patch called a ** spectacle piece.'" This is used to repair a crack situated between the tube ends. These are usually caused (if the metal is not of bad quality) by allowing incrustation to collect on the plate inside the boiler, or by opening the furnace and smoke doors, thus allowing a current of cold air to contract the metal of the plates round the The *' spectacle piece 'Ms bored out to encircle the tabes adjacent to the crack, or in other words, to be a duplicate of a portion of the tube plate cracked. These plates are then pinned on to the tube covering the crack. Steam generators, as they are exposed to more or less of try- ing service in steam production develop almost an unending number and variety of defects. When a boiler is new and first set up it is supposed to be clean, inside and out, but even one day's service changes its condition ; sediment has collected within and soot and ashes without. Unlike animals and plants they have no recuperative powers of their own — whenever they become weakened at any point the natural course of the defect is to become continually worse. In nothing can an engineer better show his true fitness than in the treatment of the beginnings of defects as they show themselves by well known signs of distress, such as leaks of water about the tube ends, and in the boiler below the water line, or escaping steam above it. In more serious cases, the professional services of a skillful and honest boiler maker is the best for the occasion. Maxims and Instructions, J2^ DEFECTS AND NECESSARY REPAIRS. In a recent report given in by the Inspectors the following list of defects in -boilers coming nnder their observation was re- ported. The items indicate the nature of the natural decay to which steam boilers in active use are exposed. The added col- umn under the heading of ^' dangerous" carries its own lesson, urging the importance of vigilance and skill on the part of the engineer in charge. Nature of Defects. Whole Number. Dangerous. Cases of deposit of sediment 419 36 Cases of incrustation and scale 696 44 Oases of internal grooving 25 16 Cases of internal corrosion 139 21 Cases of external corrosion 347 114 Broken and loose braces and stays 83 50 Settings defective 129 14 Furnaces out of shape 171 14 Fractured plates 181 84 Burned plates 93 31 Blistered plates 232 22 Cases of defective riveting 306 34 Defective heads 36 20 Serious leakage around tube ends ...... . 549 57 Serious leakage at seams 214 53 Defective water gauges 128 14 Defective blow-offs 45 9 Cases of deficiency of water 9 4 Safety-valves overloaded 22 7 Safety-valves defective in construction . . 41 16 Pressure-gauges defective 211 29 Boiler without pressure-gauges 3 This list covers nearly, if not all, the points of danger against which the vigilance of both engineer and fireman should be continually on guard; and is worth constant study until thor- oughly memorized. Note. Probably one-quarter, if not one-third, of all boiler-work is done in the way of repairs, hence the advice of men who have had long experience in the trade is the one safe thing to follow for the avoidance of danger and greater losses, and for the best results the united opinion of 1, the engineer, experienced in his own boiler and 2, the boiler-maker with his wider observa- tion and 3, the owner of the steam plant, all of whom are most interested. 126 Maxims and Instructions, DEFECTS AND NECESSARY REPAIRS. Corrosion is a trouble from which few if any boilers escape. The principal causes of external corrosion arise from undue ex- posure to the weather, improper setting, or possibly damp brick work, leakage consequent upon faulty construction, or negli- ence on the part of those haying them in charge. Internal corrosion may be divided into ordinary corroding, or rusting and pitting. Ordinary corrosion is sometimes uniform through a large portion of the boiler, but is often found in iso- lated patches which have been difficult to account for. Pit- ting is still more capricious in the location of its attack ; it may be described as a series of holes often running into each other in lines and patches, eaten into the surface of the iron to a depth sometimes of one- quarter of an inch. Pitting is the more dangerous form of corrosion, and the dangers are increased when its existence is hidden beneath a coating of scale. There IS another form of decay in boilers known as grooving ; it may be described as surface cracking of iron, caused by its expansion and contraction, under the influence of differing temperatures. It is attributable generally to the too great rigidity of the parts of the boiler affected, and it may be looked upon as resulting from faulty construction. n \ Fig. 69. In plugging a leaky tube with a pine plug, make a email hole, of -iz of an inch diameter, or less, running through it from end to end. These plugs should never have a taper of more than \ of an inch to the foot. It is well to have a few plugs always on hand. Fig. 69 exhibits the best shape for the wooden plug. Maxims and Instructions. taf QUESTIONS BY THE PROPRIHTOR TO THE EIS^GIKEER Iiq" CHARGE, RELAT- ING TO CONDITION OF THE BOILER. How long since you were inside your boiler? Were any of the braces slack ? Were any of the pins out of the braces? Did all the braces ring alike ? Did not some of them sound like a fiddle-string ? Did you notice any scale on flues or crown sheet ? If you did, when do you intend to remove it ? Have you noticed any evidence of bulging in the fire-box plates ? Do you know of any leaky socket bolts ? Are any of the flange joints leaking ? Will your safety valve blow off itself, or does it stick a little sometimes ? Are there any globe valves between the safety valve and the boiler ? They shpuld be taken out at once, if there are. Are there any defective plates anywhere about your boiler ? Is the boiler so set that you can inspect every part of it when necessary ? If not, how can you tell in what condition the plates are 'i Are not some of the lower courses of tubes or flues in your boiler choked with soot or ashes ? Do you absolutely know, of your own knowledge, that your boiler is in safe and economical working order, or do you merely suppose it is ? QUESTIONS ASKED OP A CANDIDATE FOR A MARINE LICENSE RELATING TO DEFECTS IN BOILER WITH ANSWERS. If you find a thin plate, what would you do ? Put a patch oiu 128 Maxims and Instructions. QUESTIONS AND ANSWERS RELATING TO THE MAEINB BOILER. Would you put it on inside or outside ? Inside. Wliy so ? Because the action that has weakened the plate will then act on the patch, and when this is worn it can be replaced ; but the plate remains as we found it. If the patch were put on the outside, the action would still be on the plate, which would in time be worn through, then the pressure of the steam would force the water between the plate and the patch, and so corrode it ; and during a jerk or ex- tra pressure, the patch might be blown off. It is on the same principle that mud-hole doors are on the inside. K you found several thin places, what would you do ? Patch each, and reduce the pressure. If you found a blistered plate ? Put a patch on the fire side. If you found a plate at the bottom buckled ? Put a stay through the centre of the buckle. If you found seyeral ? Stay each, and reduce the pressure. The crown of the furnace down ? Put a stay through the middle, and a dog across the top. If a length of the crown were down, put a series of stays and dogs. A cracked plate ? Drill a hole at each end of the crack ; caulk the crack, or put a patch oyer it. If the water in the boiler is suffered to get too low, v/hat may be the consequence ? Burn the top of the combustion chamber and the tubes j perhaps cause an explosion. If suffered to get too high ? Cause priming ; perhaps cause the breaking of the cylin- der covers. Maxims and Instructions, I2g THE INSPECTION" OF STEAM BOILERS. Let ifc be clearly understood that if there were no steam generators using steam under pressure there ivoiild he no boiler inspection, and no licensing of engineers; it requires no license to be a machinist or a machine tender, no more would a license be essential to run a steam engine, except it were connected with the boiler. Tlie danger to the ^uUic arising from their use requires that the care and management of high pressure steam boilers shall be in hands of careful, experienced and nat" urally ingenious men, hence it is on tho affairs of the Boiler Eoom that the first tests are made, as to the worthiness of an aspirant for an engineer's license, hence too, the success of many firemen in obtaining the preference over engine-builders or school graduates, in the line of promotion as steam engi- neers. The inspection laws of the yarious states and cities are framed after substantially the same leading ideas, and in presenting one the others may be assumed to be nearly the same. The special province of the Steam Boiler Inspection and Engineers' Bureau in the police department in New York City is to inspect and test all the steam boilers in the city, at certain stated periods, and to examine every applicant for f;he position of engineer as to his ability and qualifications for running an engine and boiler with safety. According to the laws of the State, every owner, agent or lessee, of a steam boiler or boilers, in the city of New York, shall anually report to the board of police, the location of said boiler or boilers, and, thereupon, the officers in command of the sanitary company shall detail a practical engineer, who shall proceed to inspect such steam boiler or boilers, and all appa- ratus and appliances connected therewith. '^ When a notice is received from any owner or agent that he has one or more boilers for inspection, a printed blank is re- turned to him stating that on the day named therein the boiler^ 1^0 Maxims and Instructions. INSPECTION OF STEAM BOILERS. will be tested, and he is asked to make full preparation for the inspection by complying with the following rules ; Be ready to Lest at the above named time. Have boiler filled with water to safety valve. Have \\ inch connection. Have steam gauge. Steam allowed two-thirds amount of hydrostatic pressure. More particularly stated, the following have been adopted by one or more Inspection Companies. How TO PREPAEB FOR StEAM BoILER IkSPECTIOH. 1. Haul fires and all ashes from furnaces and ash pits. 2. If time will permit, allow boiler and settings to cool gradually until there is no steam pressure, then allow water to run out of boilers. It is best that steam pressure should not exceed ten pounds if used to blow water out. 3. Inside of boiler should be washed and dried through m^holes and handholes by hose service and wiping. 4. Keep safety valves and gauge cocks open. 5. Take off manhole and handhole plates as soon as possible after steam is oat of boiler, that boiler may cool inside sufficiently for examination ; also Iceep all doors shut about boilers and settings, except the furnace and ash pit doors. Keep dampers open in pipes and chimneys, 6. Have all ashes removed from under boilers, and fire sur- faces of shell and heads swept clean. 7. Have spare packing ready for use on manhole and hand- hole plates, if the old packing is made useless in taking off or is burned. The boiler attendant is to take off and replace these plates. 8. Keep all windows and doors to boiler room open, after fires are hauled, so that boilers and settings may cool q,s quickly as t)o^sib>Q Maxims and Instructions, Ijr INSPECTION OF STEAM BOILERS. 9. Particular attention is called to Rule 5, respecting doors — which should be open and which closed— also arrange- ment of damper. The importance of cooling the inside of the boiler by removal of manhole and handhole plates at the same time the outside is cooling, is in equalizing the process of con- traction, ISSTJINa CERTIFICATES. These conditions having been complied with, the boiler is thoroughly tested, and if it is deemed capable of doing the work required of it, a number by which it shall hereafter be known and designated is placed upon it in accordance with the city ordinance : Failure to comply with this provision is pun- ishable by a fine of $25. A certificate of inspection is then given to the owner, for which a fee of |3 is paid. This certificate sets forth that on the day named the boiler therein described was subject to a hydrostatic pressnre of a cer- tain number of pounds to the square inch. The certificate tells where the boiler was built, its style or character and '^now appears to be in good condition and safe to sustain a working pressure of to the square inch. The safety valve has been set to said pressure. ^^ A duplicate of this certificate is posted in full view in the boiler-room. In case the boiler does not stand the test to which it is subject, it must be immediately repaired and put in good working order before a certificate will be issued. THE HYDRAULIC TEST. The hydraulic test is a very convenient method of testing the tightness of the luorh in a neiu toiler, in conjunction with inspection to a greater or lesser degree, in the passing of new work. As a detector of leakages it has no rival, and its appli- cation enables faulty caulking to be made good before the boiler has left the works, and before a leak has time to enter on its insidious career of corrosion. The extent to which it en- ables the soundness and quality of the work to be ascertained is another matter, and depends on several conditions. It will be evident that if the test be applied with this object to a new boiler, the pressure should range to some point in excess of the 1^2 Maxims and Instructions. INSPECTION OF STEAM BOILERS. working load if such a test is to be of any practical value. What the excess should be so as to remain within safe limits cannot be stated without regard being paid to the factor of safety adopted in the structure. In addition to the advantage which the hydraulic test affords as a means of proving the tightness of the riveted seams and work generally, it is also of frequent assistance in determining the sufficiency of the staying of flat surfaces, especially when of indeterminate shape, or when the stresses thrown upon them by the peculiar construction of the boiler are of uncertain mag- nitude. For the hydraulic test, however, to be of any real value in the special cases to which we refer, it is essential that it should be conducted by an expert, and the application of the pressure accompanied by careful gaugings, so as to enable the amount of bulging and permanent set to be ascertained. With- out such readings the application of the test in such cases is worthless, and may be delusive. Indeed, the careful gauging of a boiler as a record of its behavior should be a condition of every test, and is a duty requiring for its adequate performance a skilled inspector. The duty of inspecting a new boiler or witnessing the hy- draulic test properly belongs to one of the regular inspecting companies, who have men in their employ specially trained for the performance of such work. The advantage accruing from such a course is well worth the fee charged for the service, and secures a searching inspection of the workmanship, which fre- quently brings to light defects and oversights that a mere pump- ing-up of the boiler would never reveal. Such a proceeding in fact, can only prove that the boiler is water-tight, and a boiler may be tight under test although the workmanship is of the poorest character. Besides, it is well to bear in mind that the tightness of a boiler under test is no guarantee of its tight- ness after it is got to work. In a word, as far as new boilers are concerned, the ajoplication of hydraulic pressure unaccom- panied by careful inspection and guagings may be almost worth- less, while with these additions it may be extremely valuable, especially in the case of boilers of peculiar shape, and is a pre- caution that should not be neglected. Maxims and Instructions, ijj ENGINEEES' EXAMIN'ATlOJSrS. Keeping in mind the fact that if there were no steam-boilers there would le no examinations and no public necessity for licenses, these ^* points'' are added. Examinations are trying periods with all engineers, as the best are liable to fail in their answers from a nervous dread of the ordeal, but the granting of the document is yery largely influenced by the personal experience of the candidate in the practical duties of the engine and boiler room, which must be stated and certified to by the evidence of others. A general "knowledge of the suhject of steam engineering is the first requisite to success, A few sample questions are here given to show the ordinary course pursued by examiners to determine the fitness of applicants: How long have you been employed as an engineer, and where ? Are f ou a mechanic ? Where did you learn your trade ? Give some idea of the extent of your experience as an engineer ? What kind of boil- r^rs have you had charge of? Describe a horizontal tubular boiler. Describe a locomotive style boiler. Describe a vertical style boiler. Describe a sectional water tube boiler. How thick is the iron in the ishell of your boiler ? How thick should it be in the shell of your boiler ? How thick are the Leads m your boiler ? How thick should they be in your boiler? How are the heads fastened to the shell? What is the best way to put heads in a boiler ? How is the shell riv- cteci? What size rivets are used? What distance apart are they? How should the shell be riveted ? Why do they double rivet some seams? What ones are best double riveted? How is a horizontal boiler braced ? How is a locomotive boiler braced ? What is the size of and forms of braces generally used ? Wnat is the size of your boil- er or boilers, length and diameter ? How many have you in charge ? Name the horse-power. How many tubes are in the boiler ? What size are they, and how thick? How long are they? How are they secured ? What is the difference between a socket and a stay bolt ? What is the tensile strength of Boiler Iron? What is the tensile strength cf Boiler Steel? What is mild steel? What is CH No. 1 Iron? What is Flange Iron? What is Hot Short and Cold Short Iron? What is the common dimensions of a Man Hole? What is it for? What are Hand Holes for? Do you open them often ? Plow often? What are Crown Bars and where are they used? How is a poller Caulked? What is a Drift Piii? IJ4 Maxims and Instructions. MECHANICAL STOKERS. In the back counties of England for many genoxations before the steam engine was eyolyed from the brains of Trevethick, Watt and Stephenson, the word ^^ stoke ^^ was used, meaning to ''stir the fire/^ The word was derived from an ancient word, stoko, meaning a stick, stock or post. To-day there are very many men who are called '''stokers,'" employed principally on locomotive engines, steam vessels, etc., and then there is the ''stoke-hole,^' so-called, in which they do their work. But, now comes the "mechanical stoker,'^ which is well, named, as its office is to feed and " stir the fire " by a machine, thus relieving the fireman from much excessively hard toil and allowing the time and energy thus saved to be more profitably used elsewhere. The figure shows a view of the American Stoker which is a device of the most advanced type. The principal parts of the machine are : ], the Hopper, which may be filled either by hand shoveling or by elevating and conveying machinery; 2, the Conveyor Screw, which forces the coal, or indeed, any description of fuel, forward to the, 3, Magazine, shown in the figure to the left ; 4, a Driving Mechanism, which is a steam motor arranged conveniently in front of the hopper ; 5, the Eetort, so called from its being the place (above the conveyor) where the coal is distilled into gas. Note. - An illustrated printed description of tliis machine is issued and sent free upon appUcation by the makers, The American Stoker Co. , Washington Life Building, Cor. Broadway and Liberty St. , New York, Maxims and Instructions. ij£ MECHANICAL STOKERS. The rate of feeding coal is controlled by the speed of the motor, this being effected by the simple means of throttling the steam in the supply pipe to the motor. The shields cover- ing the motor effectually protect the mechanism from dirt and dust. The motor has a simple reciprocating piston ; its piston rod carries a crosshead, which, by means of suitable connecting links, operates a rocker arm having a pawl mechanism, which 'in, turn actuates the ratchet wheel attached to the conveyor shaft. The stoker is thus entirely self-contained and complete in itself. A screw conveyor or worm is located in the conveyor pipe and extends the entire length of the magazine. Immediately beneath the conveyor pipe is located the wind box, having an opening beneath the hopper. At this point is connected the piping for the air supply, furnished at low pressure by a volume blower. The other end of the wind-box opens into the air space between the magazine and outer casing. The upper edge of the magazine is surrounded by tuyeres, or air blocks, these being provided with openings for the discharge of air, inwardly and outwardly. The stoker rests on the front and rear bearing bars ; the space between the sides of the stoker and side walls is filled with iron plates, termed ^^dead grates.''^ Steam is carried to the motor by a f-inch steam, pipe. The exhaust steam from the motor is discharged into the ash pit. In operation the coal is fed into the hopper, carried by the conveyor into the magazine, which it fills, ^^ overflows^' on both sides, and spreads upon the sides of the grates. The coal is fed slowly and continuously, and, approaching the fire in its upward course, it is slowly roasted and coked, and the gases released from it are taken up by the fresh air entering through the tuyeres, which explodes these gases and delivers the coal as coke on the grates above. The continuous feeding gives a breathing motion to this coke bed, thus keeping it open and free for the circulation of air. It will be noted that in this machine the fuel is introduced from the bottom of the bed of fuel, technically speaking, upon the principle of ^' underfeeding." Ij6 Maxims and Instructions, CHEMICAL TEKMS AND EXPLAKATIONS EELATIKG TO FEED WATERS. Chenfiistry is a science whicli investigates the composition and properties of material substances. Nature is composed of elementary elements ; knowledge of these bodies, of their mutual combinations, of the forces by which these combinations are brought about, and the laws in accordance with which these forces act, constitute chemistry, and the chemistry of steam engineering largely deals with the for- eign bodies contained in the feed water of steam boilers. ElemenU In general, the word element is applied to any substance which has as yet never been decomposed into constitu- ents or transmuted to any other substance, and which differs in some essential property from every other known body. The term simple or undecomposed substance is often used synony- mously with element. There are about 70 simple elements, three quarters of which are to be met with only in minute quantities and are called rare elements. Copper, silver, gold, iron, and sulphur are simple elements — the metal irridium, for example, is a rare ele7nent — it is the metal which tips the ends of gold pens — it is heavier than gold and much more valuable. Probably there are not two tons of it in existence, A. He-agent is a chemical used to investigate the qualities of some other chemical — example, hydro chloric acid is a re-agent in finding carbonic acid in lime stone, or carbonate of lime, which when treated by it will give up its free carbonic acid gas, which is the same as the gas in soda water. An Oxide is any element, such as iron, aluminium, lime, magnesia, etc., combined with oxygen. To be an oxdide it must pass through the state of oxidation. Iron after it is rusted is the oxide of iron, etc. A Carbonate is any element, such as iron, sodium, etc., which forms a union with carbonic acid — the latter is a mixture of carbon and oxygen in the proportion of 1 part of carbon to % of oxygen. Carbonic acid, as is well known, does not support combustion and is one of the gases which come from perfect Maxims and Instructions, j^f CHEMICAL TERMS RELATING TO FEED WATER, combustion. This acid, or what may be better termed a gas, is plentifully distributed by nature and is found principally com- bined with lime and magnesia, and in tbis state (?. e,y carbonate of lime and carbonate of magnesia) is one of the worst enemies to a boiler. An Acid is a liquid which contains both hydrogen and oxygen combined with some simple element such as chlorine, sulphur, etc. It will always turn blue litmus red, and has that peculiar taste known as acidity ; acids range in their power from the corrosive oil of vitriol to the pleasant picric acid which gives its flavor to fruits. Alhalies are the opposite to an acid ; they are principally potash, soda and ammonia — ^these combined with carbonic acid form carbonates. Sal-soda is carbonate of soda. A Chloride is an element combined with hydro chlorio acid — common salt is a good example of a chloride — ^being sodi- um united with the element chlorine, which is the basis of hydro chlorio acid. Chlorides are not abundant in nature but all waters contain traces of them more or less and they are not particularly dangerous to a boiler. Sulphates are formed by the action of sulphuric acid (commercially known as the oil of vitriol) upon an element, such as sodium, magnesia, etc. The union of sodium and sul- phurio acid is the well-known glauber salts — this is nothing more than sulphate of soda ; sulphate of lime is nothing more than gypsum. Sulphates are dangerous to boilers, if in large quantities should they give up their free acid — ^the action of the latter being to corrode the metal. Silica is the gritty part of sand — ^it is also the basis of all fibrous vegetable matter — a familiar example of this is the ash which shows in packing, which has been burnt by the heat in steam ; by a peculiar chemical treatment silica has been made into soluble glass — a liquid. 65 per cent, of the earth's crust is composed of silica — it is the principal part of rock — pure white sand is silica itself — it is composed of an element called silicon combined with the oxygen of the air. Owing to its abundance in nature and its peculiar solubility it is found largely in all wa- ters that come from the earth and is present in all boiler scale. Ij8 Maxims and Instructions. CHEMICAL TERMS RELATING TO FEED WATER. In water analysis the term insoluble matter, is silica. This id one of the least dangerons of all the impurities that axe in feed water, JKagnesia is a fine, light, white powder, having neither taste nor smell, almost insoluble in boiling, but less so in cold water. Magnesia as found in feed water exists in two states, oxide and a carbonate, when in the latter form and free from the traces of iron, tends to give the yellow coloring matter to scale — in R. R. work, yellow scale is called magnesia scale. Carbonate of Magnesia is somewhat more soluble in cold than in hot water, but still requires to dissolve it 9,000 parts of the latter and 2,493 of former. Magnesia, in combination with silica, enters largely into the composition of many rocks and minerals, such as soapstone, asbestos, etc. Lime, whose chemical name is calcium, is a white alkaline earthy powder obtained from the native carbonates of lime, such as the different calcerous stones and sea shells, by driving off the carbonic acid in the process of calcination or burning. Lime is procured on a large scale by burning the stone in furnaces called kilns, either mixed with the fuel or exposed to the heated air and flames that proceed from side fires through the central cavity of the furnace in which the stones are collected. The calcined stones may retain their original form or crum- ble in part to powder ; if protected from air and moisture they can afterwards be preserved without change. Soda is a greyish white solid, fusing at a red heat, volatile with difficulty, and having an intense affinity for water, with which it combines with great evolution of heat. The only reagent which is available for distinguishing its salts from those of the other alkalies is a solution of antimoniate of potash, which gives a white .precipitate even in diluted solu- tions. Sodium is the metallic "base of soda. It is silver white with a high lustre ; crystallizes in cubes ; of the consistence of wax at ordinary temperatures, and completely liquid at 194% and Maxims and Instructions. /jp CHEMICAL TERMS RELATING TO FEED WATER. volatilizes at a bright red lieat. It is very generally diffused throughout nature though apparently somewhat less abundantly than potassium in the solid crust of the globe. Halt, the chloride of sodium, a natural compound of one atom of chloride and one of sodium. It occurs as a rock inter- stratified with marl, and sandstones, and gypsum, and as an element of salt springs, sea water, and salt water lakes. The proportions of its elements are 60.4 percent, of chlorine and 39.6 percent, of sodium. In salt made of sea water the salts of magnesia with a little sulphate of lime are the principal impurities. The above mentioned chemical substances can be classified into two distinct classes, i.e., incrusting and non-incrusting. Of the incrusting salts, carbonate of magnesia is the most objectionable and any feed v/ater that contains a dozen grains per gallon of magnesia can be expected to have a most injurious effect on the boiler causing corrosion and pitting. Carbonate of lime, while not as bad as the magnesia carbonate, yet has a very destructive action on a boiler and 20 grains per gallon of this is considered bad water. All silicates, oxides of iron, and aluminium, and sulphate of lime are also incrusting. The non-incrusting substances are three, viz., chloride of sodium (common salt), and sulphate and carbonate of soda. KOTE. In view of the increasing importance laid upon a knowledge of the chemical formation cf feed water, these chapters of Chemical Terms and Analysis of Feed Waters are given to indicate tlie direction in ichich the advanced engineer must push his inquiries. There are more millions of treasure to be made by properly '* treating ^^ the water which enters the steam gen- erators of the world than can be extracted from its gold mines. An important " point " is to make sure, before adopting any permanent system for purifying the waters of a steam plant, that it is always the same in its ingredients, i. e, that the impurities pont^ined in the water are the game at all times. t^O Maxims and Instructions, ANALYSIS OF FEED WATER. In response to a generous offer made by a leading engineering journal, the following compositions of feed water were ascer- tained and published. The ^'Directions'* show how the water was forwarded, and the tables the result of careful examination of samples sent from widely separated sections of the country. DiEECTIOKS. 1. Get a clean gallon jug or bottle and a new cork (or, at all events, a thoroughly clean one). 2. Wash out the vessel two or three times with the same water that is going to be sent in it. This is to make sure that the sample may not be contaminated with any '^ foreign '* in- gredient. 3. Tie the cork, after the bottle is filled with the water, with a strong string or wire. Pack the bottle so secure, with hay or straw, sawdust, or newspapers, that it may not knock itself to pieces against the sides of the box. FBOM AR(K)S, INO. Grains per Gallon. Silica 1.1096 Oxides of iron and aluminium 1752 Carbonate of lime 11 . 9010 Carbonate of magnesia 5.4597 Carbonate of soda 1 . 1324 Chloride of sodium 0715 Total soUds 19.8494 FROM SIOUX FALLS, S. D. Grains per Gallon. SiUca 8292 Oxides of iron and aluminium .2452 Carbonate of lime 9.0699 Carbonate of magnesia 5 .4376 Chloride of sodium 1 .7172 Sulphate of sodium 4. 5245 Sulphate of lime 2.0976 Total solids ,...,. 25.093^ Maxims and Instructions. i^l ANALYSIS OF FEED WATER. FROM LITCHFIELD, ILL. Grains per Gallon. SiHca 4711 Oxides of iron and aluminium 7475 Carbonate of lime 3800 Carbonate of magnesia 2 . 2911 Chloride of sodium , 8 . 7543 Sulphate of soda 16.0329 Sulphate of lime 2.8168 Total solids 31.4835 FROM CHELSEA, MASS. Grains per Gallon. Silica 1168 Oxides of iron and aluminium 6540 Carbonate of lime 34.5260 Carbonate of magnesia 22.8470 Chloride of sodium 63.2041 Sulphate of soda 28.4711 Carbonate of soda 32.2321 Total solids 182.0511 FROM MEMPHIS, TENN. Grains per Gallon. Silica 8292 Oxides of iron and aluminium 4789 Carbonate of lime 1.8337 Carbonate of magnesia 9956 Carbonate of soda 1 . 9792 Total solids 6.1166 FROM PEKiN, ILL. Grains per Gallon. Silica 1.0628 Oxides of iron and aluminium Trace Carbonate of lime 10.0915 Carbonate of magnesia 5.8224 Chloride of sodium Trace Sulphate of soda 1,2456 Total solids. 18.6471 FROM TIFFIN, OHIO. Grains per Gallon. SiUca. . . 5256 Oxides of iron and aluminium. 2336 Carbonate of lime 12.6144 Carbonate of magnesia. 10 . 2652 Carbonate of soda 2.4137 Sulphate of soda 6.8296 Chloride of sodium 1 . 0484 Total solids , . . , 33 . 939$ l/f2 ' Maxims and Jnstructwns^ OORROSIOH AND IKCRUSTATIOK OF STEAM BOILERS. No more perplexing question presents itself to the engineer and steam user than the one to be inferred from the above heading. Enormous losses of money, danger to life and property and the loss of position and the reputation of the engineer are involved in it. How to avoid these actual evils is of the first importance in steam economy. The subject at first eight seems to the average student a difficult one to master, but like all other matters pertaining to mechanics, investigatiou that is backed with reason, will show that much that appears obscure is really very plain indeed; this is because nature, even down to the sediment remaining in a boiler after the conver- sion of water into steam, operates in its formation with infinite exactness and along well known lines. Question. — What is cov-ooion ? Answer. — Corrosion is simply rusting or the wasting away of the surfaces of metals, for particulars of which see page 126. Question. — What is Incrustation ? Answer. — Incrustation means simply a coating over. Water, on becoming steam, is separated from the impurities which it may have contained, and these form sediment and incrustation. Boilers corrode on the outside as well as within, and to a great extent unless carefully cleaned and painted ; but it is the damage caused by ''hard" and accidulated water within the boiler that is to be principally guarded against. An extreme example of incrustation has been described in that of a locomotive type of a stationary boiler. Its dimensions were : seventy-two inches in diameter, twenty- two feet long, with 153 three-inch tubes ; she> ', three-eighths ; head, three- eighths, and made of iron. The scale against the back head was nearly two inches thick and completely filled the space between the tubes, so that circulation was impossible, the only wonder being that the boiler did not give out sooner than it finally did. The scale was even with the top row of tubes, the Maxims and Instructions, I^J CORROSION AND INCRUSTATION OF STEAM BOILERS, only part of the boiler generating steam being the fire box and the upper row of tubes, the others acting simply as smoke conduits. There was certainly a great loss of fuel, quite fifty per cent. Had it been a horizontal boiler it; would have burned out before the scale became so heavy. In the above instance, the loss in fuel is estimated at one- half. Careful experiment has proved an average loss of fuel as follows : 1-16 inch of scale causes a loss of 13 per cent of fuel. 1-4 funnel-shaped appliance placed at the opening of the upflow pipe, which, aided by the rapid flow of the hot water, carries the floating scum towards it into the reservoir. Attached to the reservoir is the blow-off pipe through which the deposited matter is removed as often as necessary. The use of these mechanical cleaners is readily understood : (1) they provide a place of accumulation for the sediment ; (3) they save the necessity of opening the boilers to remove by hand, the refuse of the boiler ; (3) save fuel by avoiding the necessity of frequent blowing off one or two guages of watier, and (4) by the preventing the formation of scale with its at* Pendant evils. Maxims and Instructions^ i6i SCUMMING APPAEATUS. In addition to tlie bottom blow-ont apparatus every boiler should be provided with m?ans for blowing out water from the surface in order to remove the fine particles of foreign matter floating there, which afterward settle and consolidate as scale on the heating surfaces. It consists, in its simplest form, of a pan, or a conical scoop. ScVVNwC^^^^ Fig. 70. near the surface of the water, but below it, connected with a pipe passing through the boiler-shell, on which is a cock, or valve, for regulating the escape of the water laden with the im- purities deposited in the pan. There are patented apparatus for this purpose which are well designed and easily fitted to a boiler. The office of the surface blow-off, illustrated in Fig. 70, IS to remove the foreign matter which is precipitated from its solution in the water. A surface blow-off used occasionally will remove the greater portion of this scum and keep the boilers reasonably free from scale and mud. Where dirty or muddy water is fed into the boilers the surface blow-off is one of the cheapest and most efficient means for keeping the boiler clean. The efficiency of the surface blow-off is not so great as that of some of the me- chanical boiler-cleaners, as by their use it is not required that any hot water shall be wasted, and this is the greatest objec- tion to the surface blow-off, as in the hands of some people a large amount of boiling water is wasted each time it is Hf'e'^ But both of th«ae arrangements arc virtuaily skimmers, as they reii^^.v. i/xic |ft-ecipitated mineral and vegetable matter from the surface of the water in the boiler. One does it by blowing ou^ j62 Maxims and Instructions, SCUMMING APPARATUS, the scum and some water at the same time, while the mechani- cal boiler-cleaner removes the scum, but returns the water to the boiler. There are several efficient ways of arranging a surface blow-off. The principal part of the blow-off is a pan or perfor- ated pipe placed horizontally at the water level having a pipe leading outside the boiler to any convenient place where the scum may be blown. When a perforated pipe is used the action is to force the scum from the top of the water during the time the valve is open, and blow it through the pipe. In using an apparatus of this kind it should be blown often, bat only for a moment at a* time, as all the scum near the pipe is removed immediately, and to keep the valve open longer than necessary to remove the scum near the pipe would allow the escape of clean water or steam which would be wasteful. If a pan is used and is fastened so that the top is secured at the ordinary water level, as shown in Fig. 70, the blow-off pipe leading from near the bottom of the pan, it will be more efficient than the perforated pipe arrangement as it will not require to be used so often, and the waste of water and steam will not be so great. The pan, by producing an eddy in the water, causes all the scum to gather orer the top, and as the water is quiet there it will gradually settle into the pan, where it will remain as mud. When the blow-off valve is opened the greater part of the mud which is gathered is blown out, and but very little water is carried with it. USE OF ZING 1^ MAKINE BOILEES. Zinc has been used in marine boilers for many years, but it was not until the publication in 1880 of the report of the Admiralty committee that the use of zinc became general. It has been used in \arious ways: 1. — Virgin spelter, as imported in oblong slabs of various sizes. 2. — Cast, or remelted zinc. 3. — Cast zinc buttons, generally made from virgin spelter or new clean zinc trimmings. 4. — Zinc spheres. 5.- -Rolled zinc blocks, generally 12 inches by 6 inches, and thicknesses vary- ing from \ inch to l^ inch, generally with a 13-1 6 mch holem the centre. Maxims and Instructions^ J(>3 USE OF ZINC IN MARINE BOILEES It is desirable that close-grained zinc of uniform structure and free from impurities should be used, and rolled zinc appears to meet this want. The wear is entirely confined to the surface. It does not appear to become distorted or broken up. On the contrary, it gradually wastes away till only a slight shred, a sort of skeleton frame work, remains to indicate what it has been. The primary object in the use of zinc in boilers is the pre- vention of corrosion, bnt it has also some effect in reducing the amount of incrustation, and rendering it softer and less adherent. Table Showing Amount of Sediment collecting in a steam toiler when evaporating 6,000 gallons per weelc, of 58,318 grains each. When a gallon of feed i water evaporated to | dryness at 212 degrees j Fahrenheit, leaves of solid matter in grains. The araonnt of solid matter collecting in boiler per weelc will be: When a gallon of feed water, evaporated to dryness at 212 degrees Fahrenheit, leaves of solid matter in grains: The amount of solid matter collecting in boiler per week will be: Grains. Pounds. Ounces. Grains. Pounds. Ounces. 1 13.714 55 47 2.285 2 1 11.428 60 51 6.857 3 2 9.143 65 55 11.428 4 3 6.857 70 60 5 4 4.571 75 64 4.571 6 5 2.285 80 68 9.143 7 6 85 72 13.714 8 6 13.714 90 77 2.285 9 7 11.428 95 81 6.857 10 8 9.142 100 85 11.428 15 12 13.713 110 94 4.571 20 17 2.284 120 102 13.714 25 21 6.855 130 111 6.857 30 25 11.426 140 120 35 30 150 128 9.142 40 34 4.571 160 137 2.285 45 38 9.143 170 145 11.428 60 42 13.714 180 154 4.571 /<5^ Maxims and Instructions. BOILER FIXTTJRES AKD BELONGINGS. A boiler is not complete wifchout certain fixtures. There must be a feed-pump or injector, with a supply-pipe, feed-valve, safety feed -valve, and cbeck- valve, in order to supply water properly to the boiler; gauge-cocks, a glass water-gauge, a blow- pipe, with its valve, to reduce the height of the water in the boiler, or to empty it entirely; a safety-valve to allow the steam to escape from the boiler when it exceeds a fixed pressure; a scumming apparatus to remove the foreign matters from the water as much as possible; a steam-pipe to convey the steam to the place where it is wanted; man-holes and hand-holes, with their covers and guards, for examination and cleaning; a non- corrosive steam-gauge, to accurately indicate at all times the amount of pressure in the boiler; and a fusible pl'\g to give warning in case of ** low water." Thus we see that in speaking of a boiler, not only the boiler proper is meant, but also the whole of its fixtures and belong- ings, of which the following is only a partial list: Feed Pump, Surface Blow Cocks, Injector or Inspirator, Grate Bars, Check Valve, Baffle or Shield Plates, Guage Cocks, Mud Drum, Glass Water Gna^ Feed Water Heaters, Try Cocks, Boiler Fronts, Blow-out Apparatus^ Dead Plate, Blow-off Valve, Steam Pressure Recording Safety VaJve, Guage, Scum Apparatus, Drain Cock for Steam Guage^ Steam Guage, Steam Trap, Fusible Plug, Steam Whistle, Maxims and Instructions, i6^ BOILER FIXTURES. All these are attachments to the boiler proper, having direct reference to its internal functions; but in addition there are tbe lugs, pedestals, or brackets which support the boiler; the masonry in which it is set, with its binders, rods, and wall- plates; the boiler front, with its doors, anchor-bolts, etc.; the arch-plates, bearer-bars, grate-bars, and dampers, an I last, bufc not least, the chimney. These are all equally necessary to enable the boiler to perform its duty properly. And besides, there are required fire-tools, fliie brushes and scrapers, and scaling tools, with hose also, to wash out the boiler, to say nothing of hammers, chisels, wrenches, etc. The fittings and attachments of the marine boiler are similar to those belonging to the land steam generators, and vary only in accommodating themselves to their peculiar surroundings. The proper operation of the boiler as to efficiency and econ- omy is largely dependent upon the number, appropriate pro- portion and harmony of action of its numerous attachments, and the utmost care and skill are requisite for designing and attaching them. It mnst not be supposed that a complete list and description of all steam boiler attachments are here presented — that were a task beyond the limits of the entire volume. BOILER FRONTS. Boiler fronts are made in many different styles, almost every maker having some peculiar points in design that- he uses on his own boilers and which nobody else nses. In the illustrations here given may be seen the four princi- pal designs : 1. The flush front as shown in Fig. 72. 2. The overhanging front as seen in Fig. 73, 5 . The cutaway front. Fig. 74. 4. Fronts with breaching as shown in Fig. 75. The flush front is one of the earliest forms of fronts, and though it often gives good satisfaction, yet it is liable to certain accidents. 66 Maxims and Instructions. Flush Front.— Fig. 72. BOILER FRONTS. As will be seen from cut 72, the front of the smoke arch,, in this form of setting, is flush with the front of the brickwork, and the dry sheet just outside of the front head is built into the brick- work. The heat from the fire, striking through the brickwork, impinges on this sheet, which is unprotected by water on the inside. So long as the furnace walls are in proper condition the heat thus transmitted should not be SLifEcient to give trouble; but after running some time bricks are very apt to fall away from over the fire door, and thus expose portions of the dry sheet to the direct action of the fire, causing it to be burned or otherwise injured by the heat, and perhaps Etartmg a leakage around the front row of rivets when the head is attached to the shelL In the overhanging front this tendency is entirely prevented by setting the boiler in such a manner that the dry sheet projects out into the boiler roo7n. If the brickwork over the fire door falls away when a boiler is set in this man- Maxims and Instructzons. 16'^ BOILER FRONTS. ner, the only effect is to slightly increase the heating surface. No damage can be done, since the sheet against which the heat would strike is protected by water on the inside. The objection is some- times raised against the pro- jecting front, that it is in the way of the fireman. To meet this point and yet pre- serve all the advantages of this kind of front, the cut- away style has come into use. In this form the lower por- tion or the front sheet is cut obliquely away, so that at the lowest point the boiler projects but little beyond the brickwork. It will be noticed that in the flush and overhang- ing fronts, the doors open sidewise, swing about on vertical hinges; in the cutaway front the best way to arrauge the tube dooristorunahingealong the top of it, horizontally, and to have the door open upward. But with such a disposition of things the door is not easy to handle. For the purpose of sup- port a hook and chain, hanging from the roof should be provided. Overhanging Front. — Fig. 73. c=^( Cutaway Front. — Fig. 74, i68 Maxims and Instructions, BOILER FRONTS. Fig. 75 shows a boiler the setting of which is similar in general design to the other three, except that in the place of a cast-iron front it has bolted to it a sheet iron breeching that comes down over the tubes and receives the gases of combustion from them. In Fig. 75 a manhole is shown under the tubes. This, of course, is not an essential fea- ture of the breeching, but it will be seen that manholes can readily be put below the tubes on fronts of this kind, in such a manner as to be very convenient of access. In addition fco these more general styles of boiler fronts, there are fronts designed particularly for patent boilers, water- front boilers, etc., which are made, very often, in ornamental and attractive designs. In Fig. 71 is shown a beautiful and appropriate design in use in connection with water tabular boileis. Front for Manhole.— Fio-. 75. FUEl^ACE DOORS. The chief points to be considered in the design of furnace doors are to prevent the radiation of heat through them, and to provide for the admission of air above the burning fuel in order to aid in the consumption of smoke and unburnt gasses. In all cases where the doors are exposed to very rough usage — such, for instance, as in locomotive and marine boilers — the means for admitting air must be of the simplest, and consist generally of small perforations as shown in Fig. 76 which re* Maxims and Instructions, i6g FURNACE DOORS. presents a front Tiew, and section of the furnace door of a locomotive boiler. The heat from the burning fuel is prevented A Pig. 76. from radiating through the perforation in the outer door, by attaching to it a second or baffle plate, a, at a distance of about 1 J inches, the holes in which do not coincide in direction with the door proper. By the constant entry of cold air from the outside the greater part of any heat which may be com- municated to the door by radiation or conduction is returned to the f nrnace. Doors similar to the above provide for the constant addition of limited quantities of fresh air above the fuel, but in actual practice, however, air is only needed above the fire for a few minutes after fresh fuel has been thrown on the grates and then is required in considerable quantities. In the case of land boilers, the furnace doors of which undergo comparatively mild treatment, it is possible to introduce the necersary com- plications to effect this object. J i B - !-«*«^ f^zzzzm i % Fig. 77. I^O Maxims and Instructions, FURNACE DOORS. Fig. 77 shows an arrangement largely in use in New England, in which, by means of a diaphram, the air is passed back and forth across the heated inner or baffle plate with the very best results. The air is first drawn by the natujal draught into the hollojv space between the iron door and its lining, through a row of holes A, in the lower part of the door, controlled however, by a slide not shown in the cut, then caused to flow back and forth across the width of the door by simply arranged diaphrams, and finally injected into the furnace through a series of minute apertures drilled in the upper part of the door liner, as indicated in cut at B. It will be seen that while the air may enter the door at a low temperature, it constantly becomes heated during its circulation until the instant it enters the furnace, it is ready to flash into flame with intense heat upon its incorporation with the ex- panding gasses of the furnace. An arrangement in common use in Cornish and Lancashire boilers consists of a number of radial slits in the outer door which can be closed or opened at will in the same manner as an ordinary window ventilator. Other and more complicated arrangements have been frequently devised, which work admir- ably so long as they remain in order, but the frequent banging to which furnace doors are subjected, even in factory boilers, soon deranges delicate mechanism. Furnace doors should be made as small as possible consider- ing the proper distribution of fael over the grate area, as other- wise the great rush of cold air, when the door is opened rapidly cools down the flues and does considerable injury to tube plates, etc. ; for this reason it is desirable, when grates are over forty inches in width to have two doors to each furnace, which can be fired alternately. The great loss arising from a rush of cold air on opening the furnace doors for raplenishing the fires with fuel has led to costly experiments to produce '* a mechanical stoker,^' or self boiler feeding arrangement for supplying the coal as needed. Maxims and Instructions, 171 FUSIBLE PLUGS. In some States tlie insertion of fusible plugs at the highest fire line in boilers is compelled by law under a heavy penalty. Its design is to give the most emphatic warning of low water, and at the same time relieve the boiler of dangerous press- ure. rigs. 78 and 79 exhibit two of the forms most commonly used, and on the succeed- Fig. 78. i^g P^'gG^ i^ cut 80, is shown the device in operation where the water has sunk to a dangerously low level. In the illustration the device is shown in connection with a locomotive boiler, in the common tubular boiler the plug is usually inserted in the rear head of the boiler, so that in case of its operation it will not endanger the fireman. These devices are designed to be screwed into the boiler shell at the safety line. Ths figs. 78 & 79 exhibits their construction. The part to be screwed into the boiler is called the shell and is commonly made of brass; the internal part is plug and is made of a soft metal like banca tin or a compound consisting of lead, tin and bismntl]. This composition melts easily at the proper point to allow escape, where the water has sunk to a dangerously low level. There is considerable diversity in the make up of the material used for filling the plug, which must not have its melting point at ac /thing less than the temper- ature of the steam lest it should g-> off" at the wrong time. Fio:. 79. i?3 Maxims and Instructions, FUSIBLE SAFETY PLUG. ioQOOd Fig. 80. If the accident of low water occurs at a time where it is important to continue operations with the least possible delay, a pine plug may be driven in the opening left by the melting of the fusible metal. In any event it is but a short job to re- new the fusible cap, it being only necessary to unscrew the nut and insert a new cap, the rest of the device remaining intact. The plug should be renewed occasionally and the surface ex- posed inside the boiler be kept free from scale and deposit. It is to be understood that the fusible portion extends entirely through the shell of the boiler and when melted out makes a vent for the water or steam. All marine boilers in service in the United States are required to have fusible plugs, one-half inch in diameter, made of pure tin, and nearly aH first-class boiler makers put them in each boiler they build. Maxims and Instrzictions, '73 GEATE BARS. Fig. 81. The Grate Bars are a very important part of the furnace appliances. These consist of a number of cast iron bars sup- ported on iron bearers placed at and across the front and back of the furnace. Innumerable forms of grate bars have been contrived to meet the cases of special kinds of fuel. The type in common use is represented in Fig. 82. 3? These cuts show a side view and a section of a single bar, and a plan of three bars in position. Each bar is in fact a small girder, the top surface of which is wider than the bottom. On each bar are cast lugs, the width of which de- termines the size of the opening for the passage of air. This opening varies in width according to the character of the fuel ; for anthracite f inch is a maximum, while for soft coals f to f inch is often used; for pea and nut coal still smaller openings than either of those are used, L e., i and f inches. For wood the opening should be a full inch in width. For long furnaces the bars are usually made in two lengths, with a bearer in the middle of the grate, as shown in Fig. 83, As a rule long grates are set with a considerable slope towards n4 Maxims and Instructions, GRATE BARS. Fig. 83. the bridge in order to facilitate the distribution of the fuel; an inch to a foot is the rule commonly approved. Fig. 84. Rocking and shahing grates are now very extensively used; these combine a dumping arrangement, and very largely lessen the great labor of the fireman, and by allowing the use of slack and other cheap forms of fuel are very econom- ical. Several patents are issued upon this form of grate bars all working on essentially the same principal. Fig. 84 exhib- its an efficient form of a shaking grate. As shown in the cut, the grates are arranged to dump the ashes and clinkers. By the reverse motion the flat surface of the grates are restored. Trouble with grate bars comes from warping or twisting caused by excessive heat, and burning out, produced by the same cause — this explains the peculiar shape in which grates are made — very narrow and very deep. A free introduotioa Maxims and Instructions. /75 GRATE BARS, of air not only causes perfect combustion but tends towards the preservation of the bars. Grate bars are usually placed so as to incline towards the rear, the inclination being from one to two inches; this facili- tates somewhat the throwing of the coal into the furnace. The proportion between grate and heating surface should be determined by the kind of fuel to be used. The greatest economy will be attained when the grate is of a size to cause the fire to be forced, and have the gases enter the chimney only a few degrees hotter than the water in the boiler. If the grate is too large to admit of forcing the fire, the com- bustion is naturally slower, and consequently the temperature in the furnace is lower, and the loss from the escaping gases is greater. It must be borne in mind that the only heat which can be utilized is that due to the difference in temperature between the fire and the water in the boiler. For example, if the tem- perature in the furnace be 975°, and the water in the boiler have a temperature due to 80 pounds of steam, viz. : 325°, it is evident that the heat which can be utilized is the difference between them, or f of the total heat. Now if the fire be forced, and the furnace temperature raised to 2600°, -J of the total heat can be utilized; so it can be readily seen that the grate should be of such a size as to have the fire burn rapidly. The actual ratio of grate to heating surface should not in any case be less than 1 to 40, and may with advantage, in many cases, be 1 to 50. This proportion will admit of very sharp fires, and still insure the greater portion of the heat being transmitted to the water in the boiler. The water grate bars, invented in 1824, and since frequently applied to locomotives and marine boilers, do not seem to grow in popular favor, and are scarcely known in stationary boilers. The objections urged against them are the expense of main- tenance, their fittings an^l attachments, and the possibility of serious consequences should they rupture or burn out. 176 Maxims and Instructiofis. WATER GAUGE COOKS. It is of the first importance that those in charge of a boiler shall know with certainty the position of the water leyel within the boiler. These attachments, also called Try cocks, are usually 23laced in a conspicious and accessible position on the front of boilers. They are so arranged that one will blow only steam, one at the working level of the water, and the third at the lowest water level or say three inches above the highest point of the fire line of the boiler. The cut, Fig. 85, exhibits them as commonly arranged. It is not essentially requisite, that the the cocks themselves should be placed at the point indi- cated, so long as they have pipes projecting internally into the boiler, with their ends corresponding to the height of water above mentioned. In order that these cocks may readily be cleaned out, a plug is usually fitted into bit of cock opposite the port or opening of the plug, upon removing which a pricker can be readily inserted. The gauge or cocks should be tested many times each day, and when opened the top one should always give steam and the bottom one water. They should be allowed to re- main open long enough to make sure whether steam or water is issuing from the cock. This is a matter of instruc- tion, but the beginner with a little experience can detest the difference by the sound. In so universal an appliance as this there are very many forms and arrangements, but they ^ work upon the same principle as stated above. Fig. 85. Maxims and Instructions. 177 GLASS GAUGES. These are the second and auxilliary arrangements for ascertaining the water line. Near- ly all boilers are supplied with both try cocks and glass gauges, and so important is it considered to be correctly informed as to the water line that a third method con- sisting of a float which is carried on the water surface, is sometimes added to the two named. The glass water gauge column consists of an upright casting bolted to the front of the boiler, in which are fixed two cocks having stuffing boxes for receiving the gauge glass. The lower of these cocks is also fitted with a drain cock for blowing out the glasp. The try cocks are frequently placed on the above-mentioned standard or column. The action of the gauge glass is to show the level of the water in the boiler by natural gravitation and the best posi- tion for it is in view of the engine r.)om, as close to the boiler as possible and preferably in the middle line of its diameter, at such height that its lowest portion is about two inches above the highest part of the fire line of the boiler, and its center, nine inches above that, making the total visible por- tion of glass eighteen inches longo Glass water gauges sometimes have pipe connections top mid bottom. The object of this arrangement is to have an una.s- turbed water level in the glass by carrying one pipe to the steam dome and the other near to the bottom of the boiler ; the one position not being so liable to be effected by foartiing and the other by the boiling of the water. Cocks should always be fitted to the boiler ends of these pipes, in order that lyS Maxims and Instructions, WATER GAUGES. in case of accident to tlio pipes, steam and water may be shut off. The glasses are h'able to burst and become choked up with dirt. The former defect is easily repaired by shutting off the cocks in connection with the boiler and putting in a new glass. The mud or sediment is cleaned out by opening the above- mentioned drain or blow out cock and allowing the steam or water, or both, to rush through the glass, which will effectually blow out all sediment and leave the glass in good condition again to show the height of the water in the boiler. In ojiening the cocks connected with the glasses, it should be done cautiously, as the glass is liable to burst. A strip of white running the whole length of the glass on the side toward the boiler is a great help in observing the variations of the water line in the tube. It is not needed to remove the gauge glasses to clean them. There are good fixtures in the market that by taking out the plug in the top, the glass may be cleaned with a bit of wicking on the end of a stick. A slight scratch will break the glass, hence do not use wire. Use soft rubber gaskets when setting the glass, screw up until all leaking stops. Don't let the glass come in contact with the metal anywhere. Don't try to reset the glass with an old, hard gasket. Two glasses from the same bundle will not act alike. The glasses used to show the water line are made of a soft glass known as ^Head glass," and are easily cut, or broken square across. Most oE them can be broken by filing a notch at the point at which it is necessary to break them. After filing the notch, place the thumbs as if you would break the glass ; it will crack easily, and the fracture be straight and clean. If the tube be brittle, as some are, to avoid cutting the hands wrap two pieces of paper around the glass, each side of the notch. If the ends are rough or uneven, they can be made smooth by filing or by the grindstone. The Manchester, Eng., Boiler Association attribute more accidents to inattention to water gauges than to all other causes Maxims and Instructions, lyg "WATER Gauges. put together. It is, therefore, of much importance that these glasses should be kept clean. It is not an uncommon thing to go into a boiler room and find that a leaky stufiSng box has allowed the steam or water to blow out, and, by running down the outside of the glass, leave a deposit of lime scale. Af ^?r this deposit has been formed, it is sometimes difficult to remove — and more than a few glasses have been broken by the engineer attempting to remove the scale. After this scale has once been formed, unless it is soft enough to be wiped oS with a piece of waste, it is best to take the glass out and soak or wash it in a solution of one-half muriatic acid and one-half water until it is clean or the scale so softened that it may be readily wiped off. To prevent the scale from again forming and hardening, the glass should be dipped in glycerine before re- placing. THE MUD DRUM. The mud drum is attached to a boiler with the expectation that it will catch and hold the larger portion of the sediment precipitated from the water. The mud drum to be effective should be protected from the heat of the fire, for so soon as it receives sufficient heat to boil the water within it can no longer serve the purpose for which it was intended as all the sediment which may have gathered would be expelled by the ebullition of the water. When the drum is located under the boiler it is not in a good position to catch the sediment, as the boiling water produces sufficient current to carry the sediment to the top, or keep it violently agitat:d, so that there is little opportunity for it to be deposited any where so long as the boiler is making steam. Afterward when the water is quiet the sediment for the most past is deposited on the tubes and the curve of the shell; the small portion falling into the neck of the drum serves prin- cipally to show the inefficiency of the device. Located under the boiler as it generally is, makes it extremely difficult to get at for examination, and as a consequence of its being enclosed, as it m.ust be, to be of much importance, it is subject to greater deterioration than would otherwise be the case, and as the enclosure to be most efficient would enclose the neck also, the l8o Maxims and Instructions. THE MUD DRUM, difference of expansion at or near the junction would soon produce leaking if not worse. When the mud drum is located outside the boiler walls where it wouM be most efficient, if properly connected, it loses its identity and becomes a mechan- ical boiler cleaner. In consequence of these drawbacks the mud drum is becoming antiquated as a boiler appliance, and is now seldom used. BAFFLE PLATES. These are a device sometimes used inside steam boilers to check the too sudden flow of steam towards the exit pipe, they are sim- ply plate to baffle the rush of the steam so as to ayoid foaming. In Fig. 90 baffle plate is illustrated by the division casting against which the steam strikes on its passage from the boiler to the engine. The liners or inner plates of the boiler doors are baffle plates. DEAD PLATE. This is a flat plate of iron immediately inside the furnace door and is used in many boilers in order to insure the more perfect combustion of the coal. When the fresh fuel is laid on, it is placed on the dead plate instead of on the grate ; in this position the coal is coked, the gasses from the coal being ignited as they pass over the alread}^ intensly hot fuel in the furnace, the fuel from the dead plate is pushed forward to make place for another 'sharge to be put on the dead plate. But more fre- quently, as elswhere described, the fuel is thrown over and across the dead plate directly upon the hot fire. STEAM WHISTLES. These are of two kinds, known as the bell-whistle and organ- tube whistle; the latter is now fast superceding the former on account of the simplicity of construction and superior tone. An improved form has a division in the tube so as to emit two distinct notes, which may be in harmony, or discord, and when sounded together may be heard a long distsnce. It is important that the whistle shall sound as soon as the steam is turned on; to ensure this great care must be taken to keep the whistle-pipe free from water. Maxims and Instructions, i8r THE STEAM GAUGE. The principle of construction of the dial steam gauge is, that the pressure may be indicated by means of a pointer in a divided dial similar to a clock face, but marked in division, indicating pounds pressure per square inch instead of hours and minutes. Figs. 87 and 88 show the ordinary style of gauge which con- sists of an elliptical tube, connected at one end to a steam pipe in communication with the boiler pressure and at the other end with gearing to a pointer spindle as shown in cut. An inverted syphon pipe is usually formed under the gauge, its object being to contain water and thus prevent the heat of the steam injuring the machinery of the gauge, or distorting its action by expansion. Pig. 87. Fig. 88. A small drain cock should be fitted to the leg of the S3rphon of a steam gauge, leading to the boiler, at a level with the highest point the water can rise in the other leg, otherwise an increased pressure will be indi- cated, due to the head of water which would otherwise collect in the boiler leg of the syphon. Steam gauges indicate the pressure of steam iSs Maxims and Instructions. THE STEAM GAUGE. above tlie atmosphere only, tlie total pressure being measured from a perfect vacuum which will add 14i^ lbs. on the average to the pressure shown on the steam gauge. These gauges are apt to get out of order in consequence of water lodging in the end of the heat tube and corroding the latter. It may be easily known when they are out of order by raising the pressure of the steam in the boiler and watching when it commences to blow off at the safety valve, and then noting the position of the index finger. The pressure registered by the finger should, of course, then correspond with the known blow off pressure of the valves ; if it does not, one or the other or both of these instruments must be out of order ; therefore, when this is the case and a disagreement occurs, the steam gauge may be presumed to need correction. It should also be noted that the steam gauge finger points to zero when steam pressure is cut off. A two-way cock should be used for closing the connection between the steam gauge and the boiler, and at the same time to let air into the steam gauge. The steam should never be allowed to act directly on a steam gauge when located in cold situations where they are liable to freeze. The valve on the boiler should be closed and the water allowed to drip out, and, before the steam is turned on from the boiler, the drip on the gauge should be closed, in order that sufficient steam may be condensed in the pipe to furnish the quantity of water necessary to keep the steam from striking the gauge. A ready method for leing always ahle to prove the correctness of your steam gauge. When steam is at some point not over half the usual pressure, place the ball on the safety valve at the point where it com- mences to blow off and mark the place. Move the ball twice as far from the fulcrum as this mark, and it should blow off at twice the pressure as indicated by the gauge, or it is not right. Any other relative distance may be used to advantage. Maxims and Instructions. 1S3 STEAM SEPARATOE. This appliance, which is also called an interceptor or catch water, is generally a T shaped ^ pipe. This, although not a boiler fixture or fitting, is intimately connected with them : it Is an appliance fast coming into use both for land and marine engines, to guard against the danger to steam engine cylin- ders arising from ''the prim- ing'^ of the boilers when the steam is used at a high pressure with high speed of the piston. The separator is usually Fig- ^0- placed in the engine room, so as to be well in sight. The steam is led down the pipe round a diaphragm plate and then up again to the engine steam pipe. By this means any priming or particles of water that may be brought from the boiler with the steam will fall to the bottom of the interceptor or catch water, from whence it can be blown out, according to the arrangement of the pipes, by opening the drain cook fixed on the bottom. It has a water gauge fixed on the lower end, so as to show whether water is accumulating; and the engineer's attention is required to see that this water is from time to time blown off. In the illustration. Fig. 90, is shown the simplest form in which the device can be made. The arrows exhibit the direc- tion in which the steam travels, the aperture whence the water is to be blown out and the place for attachment of a water col- umn. In practical construction the separator should have a diameter twice that of the steam pipe and be 2^ to 3 diameters long. It is often made with a round top and flat bottom and sometimes with both ends hemispherical. The division plate should extend half the diameter of the steam pipe below the level of the bottom of the steam pipe. j84 Maxims and Instructions. THE SEPARATOR. In Fig. 91 is shown an improved form of a steam separator whicli consists of a shell or casing in which there is firmly secured a double-ended cone. On this cone there arc cast a number of wings^ extending spirally along its exterior. On entering the separator the steam is spread and thrown outward by the cone and given a centrifugal motion by the spiral wings. These wings are constructed with a curved surface. It will be noticed that the steam on entering the separator is immediately expanded from a solid body into an annular space of equal volume to the steam pipe, whereby its particles are removed from the center and thus receive a greater amount of centrifugal motion. The entrained water cr grease, etc., is thus precipitated against, and flows along the shell of the sep- arator, and is collected in a well of ample proportions at base of separator, where it is entirely isolated from the flow of dry steam. SW««wV«v\*<>v«\3 o<\€sj\^^ Nrv==:r-^ rrr^^ the steam gauge. This regulator, by using the water pressure from the boiler as a motive power, becomes a complete engine without the connecting rod and crank, having a balanced piston valve, the valve stem of which is enlarged where itpasses through the upper end of the chest into a piston of small area, working in a small open ended cylinder cast on the chest. The pressure forcing this piston outward is counterbalanced by weights as shown in illustration. The differential motion is accomplished by the device shown at the top of small cylinder. FUEL ECONOMIZER AND FEED WATER PURIFIER. This device, shown in Fig. 93, is designed to utilize the waste products of combustion as they pass from the furnace to the chimney. Its use permits a high and consequently efficient temperature under the boilers and yet saves the excess of heat. It acts also as a mechanical boiler cleaner, furnishing a settling i86 Maxims and Instructions. FUEL ECONOMIZER AND FEED WATER PURIFIER. chamber for the deposit of the impurities separated by the heat which nearly equals that of the live steam in the boiler. This device adds largely to the water capacity of the boiler, frequent- ly containing one-half the weight of the water held in the boiler itself. It will be readily understood that the openings between the vertical tubes are ample for the chimney flue area and that the device is located between the chimney and the boiler, with the waste furnace heat passing between the tubes. Fig. 93. The economizer shown in Fig. 93 consists of sections of ver- tical ^\" boiler tubes fitted te their top and bottom headers by taper joints. The top headers are provided with caps over each tube to permit cleaning out the sediment and remove and replace any tube that may become damaged. The several top headers are connected together at one end by lateral openings and the bottom headers are also connected as shown in cut, having hand holes opposite each bottom header to provide for cleaning out. Maxims and Inst^Mctions. i8y FUEL ECONOMIZER AND FEED "WATER PURIFIER. Mechanical scrapers are made to travel up and down each tube to keep them clear of soot. These are controlled by an automatic mechanism and driving head, as shown in the Fig. 93. The important features about the economizer are its adapta- bility to any type of boiler, the great saving attained by utilizing that heat which has necessarily been an almost total waste, the purifying of the water by means of the intense heat and slow circulation obtained. SAFETY VALVES. The most important fitting upon a steam boiler is the safety valve. It may also be defined, as applying to all valves, that the seat of the valve is the fixed surface on which it rests or against which it presses, and the face of a valve is that part of the surface which comes in contact with the seat. The spindle is the small rod, some- times made of composition bronze, which projects upwards or downward from the middle of the valve, and so arranged that it causes the valve to raise The seat is preferably leveled Fig. 94. and drop evenly upon its seat. at an angle of forty-five degrees. Generally speaking, the safety valve is a circular valve seated on the outside of the boiler, and weighted to such an extent, that when the pressure of the steam exceeds a certain point, the valve is lifted from its seating and allows the steam to escape. Safety valves can be loaded directly with weight valves, or the load can be transmitted to the valve by a lever. Again, the end of the lever is sometimes held down by a sim- ple weight attached to it, a plan generally adopted in land i88 Maxims and Instructionu THE SAFETY VALVE, boilers ; while sometimes as in the case of locomotive and marine boilers, the lever is weighted by means of a spring, the tension of which can be adjusted. A valve much used in locomotives is shown in Fig. 94. It consists really of two valves A, A, placed side by side, at a little distance apart. A cross piece B bears upon each and to the cross piece is attached a powerful spiral spring By the lower end of which is so fixed at C that its tension can be adjusted by means of a set screw at E which is out of reach of the engine driver. Before the valves can rise they have to overcome the resistance of the spring to which the pressure is communicated by the cross piece. The spring is attached to the cross piece below the bearing points of the cross piece on the valves, hence if one of the valves should rise from its seating before the other, the spring leans a little towards this latter, easing the pressure on it, and allow- ing it to open. The rise of the valve from its seating is much greater with these directly loaded valves than when the pressure is transmitted through a lever, and thus the steam steam escapes with miich greater rapidity. A "pop^^ safety valve is a com- Fig. 95. mon form of safety valve and takes its name from the fact that it takes a little more pressure to raise it off its seat than what it is set at, conse- quently it releases itself with a ^^pop." Fig. 95 shows a form of dead weight safety valves when a is the valve which rests on the seating I, The valve is attached to the cir- cular casting A, A, A, so that both rise and fall together. The weights W, W., etc., are disposed on the casting in rings, which can be adjusted to the desired blow off press- ure. Owing to the center of gravity of the casting and weight being below the valve, the latter requires no Maxims and Instructions. iS^ THE SAFETY VALVE. guides to keep it in position. This is a great advantage aa guides frequently stick, and prevent the valve from acting. Another advantage of this form of valve is, that it is difficult to tamper with. For instance, a four inch valve, intended to blow off at 100 lbs. per square inch would require weight of over 1,200 lbs., which require a considerable bulk. An unauthorized addition of a few pounds to such a mass would make no appreciable addition to the blowing off pressure, while any effectual amount added to the weight would be immediately noticed. It is quite different with the lever safety valve about to be described, a small addition to the weight at the end of the lever is multiplied several times at the valve. TJ. S. EuLES Relating to Safety Valves. Extract from rules and regulations passed and approved Feb. 25, 1885, by the United States Board of Supervising Inspectors of Steam Vessels : Section 24. *' Lever safety valves to be attached to marine boilers shall have an area of not less than one square inch to two square feet of the grate surface in the boiler, and the seats of all such safety valves shall have an angle of inclination of forty-five degrees to the centre line of their axis. '' The valves shall be so arranged that each boiler shall have one separate safety valve, unless the arrangement is such as to preclude the possibility of shutting off the communication of any boiler with the safety valve or valves employed. This arrangement shall also apply to lock-up safety valves when they are employed. ' * Any spring-loaded safety valves constructed so as to give an increased lift by the operation of steam^, after being raised from their seats, or any spring-loaded safety valve constructed in any other manner, or so as to give an effective area equal to that of the aforementioned spring-loaded safety valve, may be used in lieu of the common lever-weighted valve on all boilers on steam vessels, and all such spring-loaded safety valves shall I go Maxims and Instructions, IT. S. RULES RELATING TO SAFETY VALVES, be required to have an area of not less than one square inch to three square feet of grate surface of the boiler, and each spring- loaded valve shall be supplied with a lever that will raise the valve from its seat a distance of not less than that equal to one- eighth the diameter of the valve-opening, and the seats of all such safety valves shall have an angle of inclination to the centre-line of their axis of forty-five degrees. But in no case shall any spring-loaded safety valve be used in lieu of the Icver- weightcd safety valve, without first having been approved by the Board of Supervising Inspectors/^ The following size ^'Pop'^ Safety Valves are required for boilers having grate surfaces as below : 2 inch ^'Pop'^ Valve for 9.42 square feet of grate surface. 24 " " '' '' 14.72 *' *^ 3 •' " " " 21.20 ^\ *' 4 *' ** '' *' 37.69 ** ** 6 ** " '' *' 58.90 " ** 6 '* *' " " 84.82 " '' Peofessoe Rai^kin's Rule. — Multiply the number of pounds of water evaporated per hour by .006, and the product will be the area in square inches of the valve. The U. S. Steamboat Inspection Law requires for the com- mon lever valve one square inch of area of valve for eyery two square feet of area of grate surface. United States Nav}^ Department deduced from a series of experiments the following rule : Multiply the number of pounds of water evaporated per hour by .005, and the product will be the area of the valve in square inches. Rule adopted by the Philadelphia Department of Steam Engine and Boiler Inspection : 1. Multiply the area of grate in square feet by the number 22.5. 2. Add the number 8. 6'3 to the pressure allowed per square inch. Divide (1) by (2) and the quotient will be the area of the val f e in square inches. This is the same as the Trench rule. Maxims and Instructions, igi SAFETY VALVE RULES. The maximum desirable diameter for safety valves is four inches, for beyond this the area and cost increase much more rapidly than the effective discharging around the circumference. There should not be any stop valve between the boiler and safety valve. The common form of safety valve is shown in Fig. 96. Here the load is attached to the end B of the lever A, B, the fulcrum of which is at c. The effective pressure on tha valve, and consequently the blowing off pressure in the boiler, can be regulated within certain limits, by sliding the weight W along the arm of the lever. In locomotive engines, as well as on marine boilers, the weight would on account of the oscillations, be inadmissible and a spring is used to hold down the lever. The pressure on the valve can be regulated by altering the tension of the spring. In the calculations regarding the lever safety valve, there are five points to be determined, and it is necessary to know four of these in order to find the fifth. These are : (1) The Steam Pressure, (2) The Weight of Ball, (3) The Area of Valve, (4) The Length of Lever, (5) The Fulcrum. Fig. 96. In making these calculations it is necessary to take into account the load on the valve due to the weight of the valve- stem and lever. The leverage with which this weight acts is measured by the distance of its centre of gravity from the fulcrum. The centre of gravity is found by balancing the lever on a knife edge, and thp weight of th^ valve-stem and tg2 Maxims and Instructions. SAFETY VALVE RULES, lever can be found by actual weighing. This load can also be found by attaching a spring balance to the lever exactly over the centre of the valve stem when they are in position. The following examples will be computed under these conditions : (1) Steam Pressure, 130 pounds; (2) Weight of Ball, 100 pounds ; (3) Weight of Valve and Lever, 60 pounds, weighed in position ; (4) Length of Lever, 45 inches ; (5) Length of Fulcrum, 5 inches ; (6) Area of Valve, 8 square inches. To find the area of the valve : EuLE. — Multiply the length of the lever by the weight of the ball, and divide the product by the fulcrum, and to the quotient add the weight of the valve and lever, and divide the sum by the steam pressure. Example. 45 inches, length of the lever, 100 pounds, weight of the ball. Fulcrum, 5 in.)4500 ~9ob 60 pounds, weight of valve and lever. Steam pressure 120 lbs.) 960(8 square inches, area of valve. 960 To find the pressure at ivhich the valve will blow off: Rule. — Multiply the length of the lever by the weight of the ball ; divide this product by the fulcrum, and to the quotient add the weight of the lever and valve, and divide the sum by the area of the valve. Example. 45 inches, length of lever, 100 pounds, weight of ball. Fulcrum 5 in.) 4500 "ioo 60 pounds, weight of valve and lever. Area of Valve 8) 960 120 pounds, pressure at which valve will blow. Maxims and Instructions, igj SAFETY VALVE RULES. To find the weight of hall : EuLE. — Multiply the steam pressure by the area of the valve, and from the product substract the weight of the valve and lever, then multiply the remainder by the fulcrum, and divide the product by the length of the lever. Example, 120 pounds, steam pressure, 8 inches, area of valve, 960 60 pounds, weight of valve and lever. 900 5 inches, fulcrum. Length of lever, 45 in.)4500 100 pounds, weight of ball. To find the length of lever : EuLE. — Multiply the steam pressure by the area of the valve, and from the product substract the weight of the valve end lever, then multiply the remainder by the fulcrum, and divide the product by the weight of the ball. Example, 120 pounds, steam pressure, 8 inches, area of valve, 960 60 pounds, weight of valve and lever. 900 5 100)4500(45 length of lever. Every boiler should be provided with two gafe1;y valves, one cf which should be put beyond the control of the attendant. The size of the openings depenc*. oi course. ur)on tbe ste9-j» producing power of the boiler. Tg^^ Maxims and Instructions. POINTS RELATING TO SAFETY VALVES. Safety valyes that stick will do so even though tried every day, if they are simjjiy lifted and dropped to the old place on the seat again. If a toiler should ie found with an excessively Mgli inessure, it tvould he one of the worst things to do to start the safety valve from its seat unless extra iveight was added, for should the valve once start, it would so suddenly relieve the boiler of such a volume of steam as would cause a rush of water to the opening, and hy a blow, just the same as in water ham- mer, rupture the boiler. Such a condition is very possible to occur of itself when a safety valve sticks. The valve holds the pressure, that gets higher and higher, until so high that the safety valve does give way and allows so much steam to escape that the sudden chang- ing of conditions sets the water in motion, and an explosion may result. The noise made by a safety valve when it is blowing off may be regarded in two ways. First, by it is known that the valve is capable of performing its proper function, and that there is, therefore, a reasonable assarance that no explosion will result from excessive pressure of steam cr other gas, and on the other hand too much noise of this kind indicates wasted fuel. The hole of the safety valve may be 2, 3 or 4 inches; that does not say that the area is 3.141 6, 7.06 or 12.56 square inches, but the area is that which is inside of the joint. The valve opening may be, say 2 inches, but the circle of contact of valve to seat may be of an average diameter of 2-J inches, if so, all the close calculations otherwise will not avail. In the first place, the area of 2 inches equals 3.1416; that of 2^ diameter equals 3.5466, showing a difference of .4 square inches. Note. Very extended rules issued by the TJ. S. Grovernment for salculating the safe working pressure, dimensions and propor- ••JDns of the safety valves for marine boilers are reprinted in •' Hawkins' Calculations" for engineers. Maxims and Instructions, ^95 POINTS EELATING TO SAFETY VALVES. When a safety valve is described as a ^'^ 2 inch safety valve/* otc, it means that 2 inches is tlie diameter of the pipe; hence the tollowing rule and examples for finding the area. Rule for fikdin^g Area of Valve Opei^in^g. Square the diameter of the opening and multiply the product by the decimal .7854. Example. What is the area of a 3 inch valve ? Now then: 3 X 3 = 9 X .7854 == 7.iVo square inches, Ans. .Note.— A shorter method of calculationg by .7854 in larger sums is to multiply by 1 1 and divide by 14, for decimal .7855 = the fraction lith. Note: .7854 is the area of a circular inch. When valves rise from their seats under increasing steam pressure they do so by a constantly diminished ratio which has been carefully determined by experiment and reduced to the following table. Pressure in Lbs. Rise of Valve. Pressure in lbs. Rise of Valve. 12 1-36 60 1-86 20 1-48 70 1-132 35 1-54 80 1-168 45 1-65 90 1-168 50 1-86 The following useful table was prepared by the Novelty Iron Wi)iks, New York. Boiler Pressure in Lbs. Above the Atmos- phere. Area of Orifir-e in Sq. In. for Each Sq. Ft. of Heating Suj face. Boiler Pressure in Lbs. Above the Atmos- phere. Area of Orifice in Sq. In. for Each Sq. Ft. of Heating Surface. 0.25 .022794 40. .001723 0.5 .021164 50. .001389 1. .018515 60. .001176 2. .014814 70. .001015 3. .012345 80. .000892 4. .010582 90. .000796 5. .009259 100. .000719 10. .005698 150. .000481 20. .003221 200. .000364 30. .002244 ig6 Maxims and Instructions. FEED WATER HEATEES. There are two general f<;rms of feed water heaters HOT WATER OUTLET • , ,, , „ , TO BOILERS lust as there are two oi steam j^ boilers, i. e., 1, the water tube heater, where the feed water passes through tJie tubes and extracts the heat from the exhaust contained in the shell of the heater. 2, the more approved form of heater where the water is held in the shell as it were in a tank, and the exhaust steam is passed through the tubes. The original feed water heater called a ^'^pot heat- er/' consisted of a vessel so constructed that the feed water was sprayed through the exhaust steam in to a globe formed tank, from the bottom of which the heated water \vas pumped into the boiler ; its name was origi- nally the "pot heater," but as it was open to the air through the ex- haust pipe, it was, with its succes- sively improved forms called the Fig. 97, open heater. Maxims and Instructions. 191 FEED WATER HEATERS. All the heat imparted to the feed water, before it enters the boiler, is so much saved, not only in the cost of fuel, but br the increased capacity of the boiler, as the fuel in the furnack will not have this duty to perform. There are two sources of waste heat which can be utilized for this purpose: the chimney gases and the exhaust steam. The gases escap- ing to the chimney after being reduced to the lowest possible temperature con- tain a considerable quan- tity of heat, 'i'his waste of heat energy may be largely saved by the device illustrated on page 186. How much saving is ob- tained under any given condition is a question requiring for its solution a careful calculation of all of the conditions which have a bearing on the subject. Exhaust steam under at- mospheric pressure only has a sensible temperature of 212 degrees, but exhaust steam contains also a large number of heat units which are given up when the steam is condensed into water; for this reason it might be thought possi- Fig. 98. ble to raise the temperature of the feed water a few degrees higher even than the sensible temperature of the exhaust steam. But this should not be expected, on account of the radiation of heat that would occur above that of the steam. The steam which escapes from the exhaust pipe dissipates into the atmosphere or discharges into the condenser over nine- igS Maxims and InstrMctions. FEED WATER HEATERS. tenths of the heat it contained , when leaving the boiler. This can be best utilized by exhaust feed ivaier heaters, for thense of live steam heaters represents no saving in fuel, as all the heat imparted to the feed water by their use comes directly from the boiler. The purpose for which they are used is to elevate the temperature of the feed water above the boiling point, so as to precipitate the sulphate of lime and other scale forming sub- stances, and prevent them from entering the boiler. Neither does the heat in the feed water introduced by an injector repre- sent saving, as it comes from the boiler and was generated by the fuel. It is important to note these two statements: 1, That neither live steam feed water heaters, nor 2, injectors save the heat from the escaping steam. It is also well to remember that it requires a pound of water to absorb 1.146 heat units, and that this quantity of heat is distributed through the whole quantity of water, and as a pound of steam is the same as a povnd of water, it may be understood that at 212° each pound of exhaust steam contains 1,14G heat units; ten pounds of steam contain 11,460 heat units distributed through the mass, etc. : thus, to explain still further: To evaporate water into steam, it must first be heated to the boiling point, and then sufficient heat still further added to change it from the liquid to the gaseous state, or steam. Take one pound of water at 32 degrees and heat it to the boiling point, it will have received 212° — 3-^° = 180 heat units. A heat unit being the amount of heat necessary to raise one pound of water through one degree at its greatest density. To convert it into steam after it has been raised to the boiling point, requires the addition of 966 heat units, -which are called latent, as they cannot be detected by the thermometer. This makes 180+966 = 114:6 heat units, which is the total heat con- tained in one pound of water made into steam at the atmos- pheric pressure. And at atmospheric density the volume of this steam is equal to 26.36 cubic feet, and this amount of steam contains 1,146 units of heat, distributed throughout the whole quantity, while the temperature at any given point at Maxims and Instructions, igg FEED WATER HEATERS, which the thermometer may be inserted is 212 degrees. If two pounds of water be evaporated, making a volume of 52.72 cubic feet, then the number of heat units present would be doubled, while the temperature would still remain at 212, the same as with one pound. If by utilizing the heat that would otherwise go to waste, the temperature of the feed water is raised 125 degrees, the saving would be tVA of the total amount of heat required for its evap- oration, or about 11 per cent. Thus it can be seen the percen- tage of saving depends upon the initial temperature of the feed water, and the pressure at which it is evaporated. For example, a boiler carrying steam at 100 pounds pressure has the temperature of the feed water raised from 60 to 200 degrees, what is the percentage of gain ? By referring to a table pressure of ^^ saturated steam,^' it will be seen that the total heat in steam at 100 pounds pressure is 1185 heat units. These calculations are from 32 degrees above zero, consequently the feed must be computed likewise. In the first case, the heat to be supplied by the furnace is the total heat, less that which the feed water contains, or 1185 — 28=1157 heat units. In the second case it is 1185 — 168 = 1017 heat units, the difference being 1157 — 1017 = 140, which repre- sents a saving of ^^, or about 12 per cent. Where feed water is heated no more than 20 degrees above its normal temperature the gain effected cannot amount to more than 2^, not sufficient to pay for the introduction and maintenance of a feed water heating device, no matter how simple, but if the temperature of the water can be increased 60 degrees the gain will be in the neighborhood of 5^. To make feed water heating practical and economical it would be neces- sary to increase the temperature of the water about 180 degrees at least, and to do this, using the exhaust from a non-condens- ing engine without back pressure, would require such a capacity of heater as would give fully 10 square feet of heating surface to each horse power of work developed, and to raise the tem- perature above this would require a certain amount of back pressure or an increased capacity of heater, so that the subject 200 Maxims and Instructions. FEED WATER HEATERS. resolves itself into a qnestion of large capacity of heater, or a higher temperature of the exhaust steam, which could only be obtained through a given amount of back pressure. In the same way has been calculated the following table, showing percentages of saving of fuel by heating feed-water to various temperatures by exhaust steam, otherwise waste: Percentage of saving, {Steam at 60 pounds gauge pressure,) '3 0"^-' Initial Temperature of "Water (Falirenheit). 60 80 [00 120 140 160 180 200 220 32Deg. 2.39 4.09 5.79 7.50 9.20 10.90 12.60 14.36 16.00 Deg. 1.71 3.43 5.14 6.85 8.57 10.28 12.00 13.71 15.42 50 Deg. 9.86 2.59 4.32 6.05 7.77 9.50 11.23 13.00 14.70 60 Deg. 1.74 3.49 5.23 6.97 8.72 10.46 12.20 14.00 70 Deg. 80 Deg. *6.'88 2.64 i.77 4.40 3.55 6.15 5.32 7.91 7.09 9.68 8.87 11.43 10.65 13.19 12.33 90 Deg. .90 2.68 4.47 8.06 9.85 11.64 100 Deg. 120 Deg. 140 Deg. 160 Deg. 1 1 80 Deg. 200 Deg. 60 80 100 120 1.8*6 140 3.61 1.84 IfiO 5.42 7.23 9.03 10.84 3.67 5.52 7.36 9.20 1.87 3.75 5.62 7.50 *i.*9i 3.82 5.73 1 i.*9G 3.93 180 200 220 1.9< ^ A good feed- water heater of adequate proportions should readily raise the temperature of feed-water up to 200° Fahr., and, as is seen by inspection of the table, thus effect a saving of fuel, ranging from 14.3 per cent, to 9.03 per cent., accord- ing as the atmospheric or normal temperature of the water varies from 32° Fahr. in the height o^ ^vinter, to 100° Fahr. in the height of summer. Maxims and Instructions, 20i POINTS RELATING TO FEED WATER HEATERS. The ]iercentage of saving which may be obtained from the use of exhaust steam for heating the feed water, with which the boiler is supplied, will depend upon the temperature to which the water is raised, and this, in turn, will depend upon the length of time that the water remains under the influence of the exhaust steam. This should be as long as possible, and unless a suflBcient amount of heating surface is employed in the heater best results cannot be expected. It does not necessarily require all the exhaust steam — or the whole volume of waste steam passing from tlie engine to bring the feed water up to the temperature desired, and the larger the heating appliance the smaller proportion is needed — hence heaters are best made with two exits nicely proportioned to avoid back pressure and at the same time utilize enough of the exhaust to heat the feed water. An improssion prevails among many who are running a con- denser on their engine that a feed water heater can not be used in connection with it ; large numbers of heaters running on condensing engines with results as follows : the feed water is delivered to the boiler at a temperature of 150° to 160° Fahr., depending on the vacuum: the higher the vacuum the less the heat in the feed water. A heater applied to a condensing engine generally increases the vacuum one to two inches. "When cold water is used for the feed water, the saving in fuel by the use of the heater is from 7 to 1 4 per cent. When feed water is taken from the hot well, it will save 7 to 8 per cent. Where all the steam generated by a boiler is used in the engine and the exhaust passed through a heater it is found by actual experiment, where iron tubes are used in the heater, that approximately ten square feet of heating surface will be required for each 30 lbs. of water vsupplied to the boiler at a temperature of 200 degrees Fahr. Ten square feet of heating surface in the feed water heater also represents one horse power. 201 Maxims and Instruction^, CAPACITY OF CISTER:N^S. The following table gives the capacity of cisterns for each twelve inches in depth: Diameter. Gallons, 25 feet 3671 30 '« 2349 15 *' 1321 14 '• 1150 13 '* 992 12 " 846 11 *• 710 10 " 587 9 " 475 8 * 376 7 " 287 6i*' 247 6 " 211 5 " 147 4i" 119 4 " 94 3 " 53 2i'* 36 2 " 23 Supposing it was required to find the weight of the water in any cistern or tank; it can be ascertained by multiplying the number of gallons by the weight of one gallon, which is 8^ pounds, 8.333. For instance, taking the largest cistern in the above table containing 3(J71 gallons: 3^,71x8.33=30579.43 pounds. The table above gives the capacities of round cisterns or tanks. If the cistern is rectangular the number of gallons and weight of water are found by multiplying the dimensions of the cistern to get the cubical contents. For instance, for a cistern or tank 96 inches long, 72 inches wide, and 48 inches deep, the formula would be: 96x72x18=331,776 cubic inches. As a gallon contains :i31 cubic inches; 331,776 divided by 231 gives 1,436 gallons, which multiplied by 8.33 will give the weight of water in the cistern. Maxims and Instructions, 20 J CAPACITY OF CISTERNS. For round cisterns or tanks, the rule is: Area of bottom on inside multiplied by the height, equals cubical capacity. For instance, taking the last tank or cistern in the table: Area of 24 inches (diameter) is 452.39, which multiplied by 12 inches (height) gives 5427. 6 cubic inches, and this divided by 231 cubic inches in a gallon gives 23 gallons. Supposing the tank to be 24 inches deep instead of 12 inches, the result v^^ould be, of course, twice the number of gallons. Rule foe Obtain^ii^g Coi^tekts of a Barrel ik Gallons. Take diameter at bung, then square it, double it, then add square of head diameter; multiply this sum by length of cask, and that proLiuct by .2618 which will give volume in cubio inches; this, divided by 231, will give result in gallons. WATER METERS. #ater meters, or measurers (apparatus for the measuremem; of water;, are constructed upon two general principles: 1, an arrangement called an '^ inferential meter'' made to divert a certain proportion of the water passing in the main pipe and by measuring accurately the small stream diverted, to infer, or estimate the larger quantity; 2, the yodtive meter; rotary piston meters are of the latter class and the form usually found in connection with steam plants. They are constructed on the positive displacement principle, and have only one working part — a hard rubber rolling piston — rendering it almost, if not entirely, exempt from liability to derangement. It measures equally well on all sized openings, whether the pressure be small or great; and its piston, being perfectly balai^^d, is almost frictionless in its operation. Constructed of composition (gun-metal) and hard rubber, it is not liable to corrosion. An ingenious stufiBng-box insures at all times a perfectly dry and legible dial, or the registering 204 Maxims and Instructions, WATER METERS, mecliaiiism which is made of a combination of metals especially chosen for durability and wear, and inclosed in a case of gun- metal. Fig. 99 is a perspective view of the meter, showing the in- dex on the top. It is shown here as when placed in position. The proper threads at the inlet and outlet make it easy of attachment to the supply and discharge pipes. The hard rubber piston (the only working part of the Me- ter), is made with spindle for moving the lever communicat- ing with the intermediate gear by which the dial is moved. Fig. 99. The water, through the continuous movement of the piston, passes through the meter in an unbroken stream, in the same quantity as with, the pipe to which it is attached whon the opening in the merer equals that of the service pipe; the appa- ratus is noiseless and practically without essential wear. "Points" Eelatii^g to Water Meters. In setting a meter in position let it be plumb, and properly secured to remain so. It should be well protected from frost. If used in connection Avith a steam boiler, or under any other conditions where it is exposed to a backpressure of steam or hot water it must be protected by a check valve, placed between the outlet of the meter and the vessel it supplies. It is absolutely necessary to blow out the supply pipe before setting a new meter, so that if there be any accumulation of sand, gravel, etc., in it, the same may be expelled, and thus prevented from entering the meter. Avoid using r^d lead in Piaking j>)ints. It is liable to vrork into the meter and cause Tx^uch annoyance by clogging the piston. Maxims and Instructions, 20S WATER METERS. This engraving. Fig. ICO, shows the counter of the Meter. It registers cubic feet — one cubic foot being TtoV U. S. gallons and is read in the same way as tho counters of gas meters. Fig. 100. The following example and directions may be of service to those unacquainted with the method : If a pointer be between two figures, the smallest one must always be taken. 7fhen the pointer is so near a figure that it poems to indicate that figure exactly, look at the dial next below it in number, and if the pointer there has passed 0, then the .count should be read for that figure. Let it be supposed that the pointers stand as in the above engraving, they then read 28,187 cubic feet. The figures are omitted from the dial marked •^^oi^e," because they represent but tenths of one cubic foot, and hence are unimportant. From dial marked '^ 10,'^ we get 7; from the next marked *^ 100," we get 8; from the next marked *' 1,000," we get the figure 1; from the next marked '' 10,000," the figure 8; from the next marked *aOO,- 000," the figure 2. The Fish Trap used in connection with water meters is an apparatus (as its name denotes) for holding back fishes, etc. 2o6 Maxims ajtd Instructions, THE STEAM BOILEE mJECTOR. For safety sake, every boiler ought to have two feeds in order to avoid accidents when one of them gets out cf order, and one of these should be an injector. This consists in its most simple form, of a steam nozzle, the end of which extends somewhat into the second nozzle, called the combining or suction nozzle; this connects with, or rather terminates in, a third nozzle or tube, termed the ^^ forcer." At the end of the combining tube, and before entering the forcer, is an opening connecting the interior of the nozzle at this point with the surrounding area. This area is connected with the outside air by a check valve, opening outward in the automatic injectors, and by a valve termed the overflow valve. The operation of the injector is based on the fact, first de- monstrated by Gifford, that the motion imparted by a jet of steam to a surrounding column of water is sufficient to force it into the boiler from which the steam was taken, and, indeed, into a boiler working at a higher pressure. The steam escaping from under pressure has, in fact, a much higher velocity than water would have under the same pressure and condition. The rate of speed at which steam — taking it at an average boiler pressure of sixty pounds — travels when discharged into the atmosphere, is about 1,700 feet per second. When discharged with the full velocity developed by the boiler pressure through a pipe, say an inch in diameter, the steam encounters the water in the combining chamber. It is immediately condensed and ifs bulk will be reduced say 1,000 times, but its velocity remains practically undiminished. Uniting with the body of water in the combining tube, it imparts to it a large share of its speed, and the body of water thus set in motion, operating against a comparatively small area of boiler pressure, is able to overcome it and pass into the boiler. The weight of the water to which steam imparts its velocity gives it a momentum that is greater in the small area in which its force is exerted than the boiler pressure, although its force has actually been derived from the bpiler pressure itself. Maxims and Instructions, 201 THE STEAM INJECTOR. The following cut 101 represents the outline of one of the best of a large number of injectors upon the market, from which the operation of injectors may be illustrated. S. Steam jet. V Suction jet , C-D. Combining and delivery tube , R. Ring or auxiliary check , P. Overflow valve . O Steam plug. M. Steam valve and stem . N. Packing nut. K. Steam valve handle X Overflow cap Fig. 101. The steam enters from above, the flow being regulated by the handle K. The sl^cam passes through the tube S and expands in the tube V, where it meets the water coming from the suc- tion pipe. The condensation takes place in the tubes V and C, and a jet of water is delivered through the forcer tube D to the boiler. Connection passages are made to the chamber surrouncl- ing the tubes 0, D, and to the end of tube V. If the pressure in this surrounding chamber becomes greater than that of the atmosphere, the check valve P is lifted and the contents are discharged through the overflow. So long as the pressure in this chamber is atmospheric, the check valve P remains closed, and all the contents must be dis- charged through the tube D. 2o8 Maxims and Instructions, THE STEAM INJECTOR. There are three distinct types of live steam injectors, the ''simple fixed nozzle/'' the ''adjustable nozzle/' and the '* double/' The first has one steam and one water nozzle which are fixed in position but are so proportioned as to yield a good result. There is a steam pressure for every instrument of this type at which it will giv3 a maximum delivery, greater than the maximum delivery for any other steam pressure either higher or lower. The second type has but one set of nozzles, but they can be so adjusted relative to each other as to produce the best results throughout a long range of action; that is to say, it so adjusts itself that its maximum delivery continually increases with the increase of steam pressure. The double injector makes use of two sets of nozzles, the ''lifter'' and *' forcer." The lifter draws the water from the reseryoir and delivers it to the forcer, which sends it into the boiler. All double injectors are fixed nozzle. All injectors are similar in their operation. They are de- signed to bring a jet of live steam from the boiler in contact with a jet of water so as to cause it to flow continuously in the direction followed by the steam, the velocity of which it in part assumes, back into the boiler and against its own pressure. As a thermodynamical machine, the injector is nearly perfect, since all the heat received by it is returned to the boiler, except such a very small part as maybe lost by radiation; consequent- ly its thermal efficiency should be in every case nearly 100 per cent. On the other hand, because of the facb that its heat energy is principally used in warming up the cold water as it enters the injector, its mechanical efficiency, or work done in lifting water, compared with the heat expended, is very low. The action of the injector is as follows: Steam being turned on, it rushes with great velocity through the steam nozzle into and through the combiniag tube. This action induces a flow of air from the suction pipe, which is connected to the combin- ing tube, with the result that a more or l:ss perfect vacuum is f(;rmed, thus inducing a flow of water. After the water com- mences to flow to the injector it receives motion from the jet of ste^m: it absorbs heat from the steam and finally condenses it^ Maxims and Instructions. 2og THE STEAM INJECTOR, and thereafter moves on into the forcer tuhe simply as a stream of water, at a low velocity compared with that of the steam. At the beginning of the forcer tube it is subjected only to atmospheric pressure, but from this point the pressure increases and the water moves forward at diminished velocity. ^^ Points'' Relating to the Injectoe. In nine cases out of ten, where the injector fails to do good service, it will be either because of its improper treatment or location, or because too much is expected of it. The experience of thoroughly competent engineers establishes the fact that in almost every instance in which a reliable boiler feed is required, an injector can be found to do the work, provided proper care is exercised in its selection. The exhaust steam injector is a type different from any of the above-named, in that it uses the exhaust steam from a non- condensing engine. Exhaust steam has fourteen and seven- tenths (14.7) pounds of work, and the steam entering the injector is condensed and the water forced into the boiler upon the same general principle as in all injectors. The exhaust steam injector would be still more extensively used were it not for a practical objection which has arisen — it carries oyer into the boiler the waste oil of the steam cylinder. Some injectors are called by special names by their makers, such as ejecters and inspirators, but the term injectors is the general name covering the principle upon which all the devices act. The injector can be and sometimes is, used as a pump to raise water from one level to another. It has been used as an air compressor, and also for receiving the exhaust from a steam engine, taking the place in that case of both condenser and air pump. The injector nozzles are tubes, with ends rounded to receive and deliver the fluids with the least possible loss by friction and eddies. Double injectors are those in which the delivery from one injector is made the supply of a second, and they will handle water at a somewhat higher temperature than single ones wi^h fixed nozzles. 210 Maxims and Instructions. POINTS RELATING TO THE INJECTOR. The motive force of tlie injector is fourd in the heat received from the steam. The steam is condensed and surrenders its latent heat and some of its sensible heat. The energy so given up by each pound of steam amounts to about 900 thermal units, each of which is equivalent to a mechanical f Dree of 778 foot pounds. This would be sufficient to rai^e a great many pounds of water against a very great pressure could it be so applied, but a large portion of it is used simply to heat the water raised by the injector. The above explanation will apply to every injector in the market, but ingenious modifications of the principles of con- struction have bften devised in order to meet a variety of re- quirements. That the condensation of the steam is necessary to complete the process will be evident, for if the steam were not condensed in the combining chamber, it would remain a light body and, though moving at high speed, would have a low degree of energy. Certain injectors will not work well when the steam pressure is too high. In order to work at all the injector must condense the steam which flows into the combining tube. Therefore, when the steam pressure is too high, and as a consequence the heat is very great, it is difficult to secure complete conden- sation; so that fur high pressure of steam good results can only be obtained with cold water. It would be well when the feed water is too warm to permit the injector to work well, to reduce the pressure, and consequently the temperature of the steam supplied to the injector, as low pressure steam condenses much easier, and consequently can be employed with better result. Throttling the steam supplied by means of stop valves will often answer well in this case. The steam should not be cold or it will not contain heat units enough to allow it to condense into a cross section small enough to be driven into the boiler. This is the reason why exhaust injectors fail to work when the exhaust steam is very cold. It also explains why such injectors work well when a little live steam is admitted into the exhaust sufficient to heat it above a temperature of 212°. Maxims and Instructions, 21 1 POINTS RELATING TO THE INJECTOR. Leaks affect injectors the same as pumps, and in addition, the accumulation of lime and other mineral deposits in the jets stops the free flowing of the water. The heat of the steam is the usual cause of the deposits, and where this is excessive it would be well to discard the injector and feed with the pump. The efficient working of the injector depends materially upon the size of the jet which should be left as the manufacturer makes it; hence in repairs and cleaning a scraper or file should not be used. For cleaning injectors, where the jets have become scaled, use a solution of one part muriatic acid to from nine to twelve parts f)f water. Allow the tubes to remain in the acid until the scale is dissolved or is so soft as to wash out readily. The lifting attachment, as applied to any injector, is simply a steam jet pump. It is combined with the injector proper and is operated by a portion of the steam admitted to the instru- ment. Nearly all the successful injectors on the market are made with these attachments, and will raise water about 25 feet if required, from a well or tank below the boiler level. Where an injector is required to work at different pressures it must be so constructed that the space between the receiving tube and the combining tube can be varied in size. As a rule this is accomplished by making both combining and receiving tubes conical in form and arranging the combining tube so that it can be moved to or from the receiving tube, and the water space thereby enlarged or contracted at will. The adjustment of the space between the two tubes by hand is a matter of some difficulty, however; at least it takes more time and patience than the average engineer has to devote to it, and the majority of the injectors in use are therefore made automatic in their regulation. '^J'he injector is not an economical device, but it is simple and convenient, it occupies but a small amount of space, is not expensive and is free from severe strains on its durability ; moreover, where a number of boilers are used in one establish- ment, it is very convenient to have the feeding arrangements separate, so that each boiler is a complete generating system ia itself and independent ot its neighbors. is 212 Maxims and Instructions, ojAws of heat. Heat is a word freely used, yet difficult to defiiie. The word heat^^ is coramonly used in two senses: (1) to express the sensation of warmth; (2) the state of things in bodies which causes that sensation. The expression herein must be taken in the latter sense. Heat is transmitted in three ways — by conduction, as when the end of a short rod of iron is placed in a fire, and the oppo- site end becomes warmed - this is conducted heat; by convection (means of currents), such as the warming of a mass of water in a boiler, furnace, or saucepan: and by radiation, as that dif- fused from a piece of hot metal or an open fire. Eadiant heat is transmitted, like sound or light, in straight lines in evei»y direction, and its intensity diminishes inyersely as the square of the distance from its center or point of radiation. Suppose the distance from the center of radiation to be \, 'I, 3 and 4 yards, tlie surface covered by heat rays will increase 1, 4, 9 and 16 square feet; the intensity of heat will diminish 1, \, 1-9, and 1-16. and so on in like proportions, until the heat becomes absorbed, or its source of supply stopped. Whenever a difference in temperature exists, either in solids or liquids that come in contact with or in close proximity to each other, there is a tendency for the temperature to become equalized; if water at 100° be poured into a vessel containing an equal quantity of water at 50°, the tendency will be for the whole to assume a temperature of 75°; and suppose the tem- perature of the surrounding air be 30°, the cooling process will continue until the water and the surrounding air become nearly equal, the temperature of the air being increased in proportion as that of the water is decreased. The heat generated by a fire under the boiler is transmitted to the water inside the boiler, when the difference in the speci- fic gravities, or, in other words, the cold water in the pipes being heavier than that in the boiler sinks and forces the lighter hot water upward. This heat is radiated from the pipes, which are good conductors of heat to the air in the room, and raises it to the required temperature. That which absorbs heat Maxims and Instructions, ^ij LAWS OF HEAT, rapidly, and parts with it rapidly, is called a good conductor, and that which is slow to receiye heat, and parts with it slowly, is termed a bad conductor. The following tables of conductivity, and of the radiating properties of various materials, may be of service: Conducting Power of Various Substances.— Desprtiz. Material. Conductivity. Gold 100 Silver 97 Copper 89 Brass 75 Cast iron 56 Wrought iron 37 Zinc ... 36 Tin 30 Lead ... 18 Marble 3.4 f'ire clay .».. .,. , 1.1 Water 0.9 Radiating Power of Various Substances.— Leslie Radiating Material. Power. Lampblack 100 Water 100 Writing paper 98 Glass 90 Tissue paper 88 Ice 85 Wrought lead 45 Mercury 20 Polished lead ^ 19 Polished iron , , 15 Gold, silver .. 12 Copper, tin 12 From the above tables, it will be seen that water, being an excellent radiator, and of great specific heat, and iron a good conductor, these qualities, together with the small cost of the materials, combine to render them efficient, economic and convenient for the transmission and distribution of artificial heat. 21^ Maxims and Instructions. LAV7S OF HEAT. By adopting certain standards we are enabled to define, com- pare and calculate so as to arrive at definite results, hence the adoption of a standard unit of heat, unit of power, unit of work, etc. The standard unit of heat is the amount necessary to raise the temperature of one pound of water at 3"-^° Fahr. on. degree, i, e., from 32" to 33°. Specific heat is the amount of heat necessary to raise the temperature of a solid or liquid body a certain number of degrees; water is adopted as the unit or standard of comparison. The heat necessary to raise one pound of water one degree, will raise one pound of mercury about 30 degrees, and one pound of lead about 32 degrees. Table of the Specific Heat of Equal Weights of Various Substances. Solid bodies. Heat. Wood (fir and pine) 0.650 «' (oak) 0.570 Ice 0. 504 Coal , 0.280 Charcoal (animal) '. 0.260 " (vegetable) ... 0.241 Iron (cast) 0.241 Coke 0.201 Limestone 0.200 Glass 0.195 Steel (hard) 0.117 ' ' (soft) 0. 116 Iron (wrought) O.lll Zinc 0.095 Copper (annealed) 0.094 ' ' (cold hammered) 0.093 Tin 0.056 Lead 0.081 Liquids. Water 1.000 Alcohol 0.158 Acid (pyroligneous) 0. 590 Ether 0.520 Acid (acetic) 0.509 Oil (olive) 0.309 Mercury 0.033 Maxims and Instructions, 2i^ LAWS OF HEAT. Qases, Hydrogen , 3.409 Vapor of alcohol 0.547 Steam , 0.480 Carbonic oxide 0.245 Nitrogen 0.243 Oxygen 0.217 Atmospheric air 0.237 Carbonic acid 0.202 THE STEAM PUMP. Jt is difficult to oyeresfcimate the importance, in connection with a steam plant, of the appliance which supplies water for the boil- er, not only, but a hundred other uses. Upon the steady operation of the pump depends the safety and comfort of the engineer, owner and employee, and indirectly of ^* * the success of the business with which the '^ plant" is connected. Hence the necessity of acquiring complete knowledge of the operation of a device so important. Pumps now raise, convey and deliver water, beer, molasses, acids, oils, melted lead. Pumps also handle, among the gases, air, ammonia, lighting gas, and oxygen. Pumps are also used to increase or decrease the pressure of a fluid. Pumps are made in many ways, and defined as rope, chain, diaphram, jet, centrifugal, rotary, oscillating, cylinder. Cylinder pumps are of two classes, single acting and double acting. In single acting — in ejffect is single ended — in double acting, the motion of the cylinder in one direction causes an inflow of water and a discharge at the same time, in the other; and on the return stroke the action is renewed as the discharge end becomes the suction end. The pump is thus double acting. 2i6 Maxims and Instructions. STEAM PUMPS. A direct pressure steam j)iinip is one in which the liquid is pressed out by the action of steam upon its surface, without the intervention of a piston. A direct acting steam pump is an engine and pump combined. A cylinder or reciprocating pump is one in which the piston or plunger, in one direction, causes a partial vacuum, to fill which the water rushes in pressed by the air on its head. Note. — A suction valve prevents the return of this water on the return stroke of the piston and a discliarge valve permits the outward passage of the fluid from the pump but not its return thereto or to the reservoir through the suction pipe. The force against which the pump works is gravity or the attraction of the earth which prevents the water from being lifted. This is shown in the fact that water can be led, or trailed, an immense distance, limited only by the friction, by a pump. Note. — It may be noted that the difference between a fluid and liquid is shown in the fact that tbe latter can be poured from one vessel to another, thus: air and water are both fluids, but of the two water alone is liquid : air, ammonia, etc., are gases, while they are also fluids, i. e,, they flow The idea entertained by many that water is raised by suction, is erroneous. Water or other liquids are raised through a tube or hose by the pressure of the atmosphere on their surface. When the atmosphere is removed from the tube there will be no resistance to prevent the water from rising, as the water outside the pipe, still having the pressure of the atmosphere upon its surface, forces water up into the pipe, supplying the place of the excluded air, while the water inside the pipe will rise above the level of that outside of it proportionally to the extent to which it is relieved of the pressure of the air. If the first stroke of a pump reduces the pressure of the air in the pipe from 15 pounds on the square inch to 14 pounds, the water will be forced up the pipe to the distance of 2i feet, since a column of water an inch square and '2\ feet high is equal Maxims and Instructions, 2IJ STEAM PUMPS. in weight to about 1 pound. Now if the second stroke of the pump reduces the pressure of the atmosphere in the pipe to 13 pounds per inch, the water will rise another 1\ feet; this rule is uniform, and shows that the rise of the column of water within the pipe is equal in weight to the pressure of the air upon the surface of the water without. There are pumps (Centrifugal) especially designed for pump- ing water mingled with mud, sand, gravel, shells, stones, coal, etc., but with these the engine or has but little to do, as they are used mostly for wrecking and drainage. The variety of pattern in which pumps are manufactured and the still greater yariation in capacity forbids an attempt to fully illustrate and describe further than their general princi- ples, and to name the following general CLASSIFICATIOiq- OF PUMPS. 1st. Pumps are divided into Vertical and HorizontaL Vertical Pumps are again divided into: 1. Ordinary Suction or Bucket Pumps. 2. Suction and Lift Pumps. 3. Plunger or Force Pumps. 4. Bucket and Plunger Pumps, 5. Piston and Plunger Pumps. Horizontal Pumps are diyided into: 1. Double-acting Piston Pumps. 2. Single-acting Plunger Pumps. 3. Double-acting Plunger Pumps. 4. Bucket and Plunger Pumps. 5. Piston and Plunger Pumps, 2lB Maxims a7td Instructions, Fig. 103. A — Air Chamber. B— Water Cylinder Ca-p, C— Water Cylinder with Valves and Seats in. D— Rocker Shafts, each, Long or Short. E— Removable Cylinders, each. F— Water Piiton and Follower, each. ii— Water Piston Followers, eack G— Rocker Stand. H — Suction Flange, threaded. I— Discharge Flange, threaded. J— Intermediate Flanges, each. K— Water Cylinder Heads, each. J'-Concaves complete, with Stuffing Boxes, each M— Steam Cylinder, without Head, Bonnet and Valve. N — Stcavn Cylinder Foot. O— Crossbead Links, each. P— Steam Piston, complete with Rings and Fol- lower, each. Piston Head. H— ^team Piston Follower. Steam Piston Rings, including Sprine and Breakjoint. . Q— Sidt Water Cylinder Bonnet, each. K— Steam Chest Bonnet, each S-Steam Chest Stuffing Box Gland, each. T— Steam Slide Valve, each. U— Piston Rods, eacb. V — ^Cros-beads, each. W— Rocker Arms, each, Long or Short. X— Valve Rod Links, each. Long or Short* Y — Steam Valve Stenw,, each. Z— Steam Cylinder Heads, each, aa-Piston Rod Nuts, each. hh— Piston Rod Stuffing Glands, each, ii — Water Valve Seats, each/ jj— Rubier Valves, each. kk— Water Valve Stems, each. II— Water Valve Springs, each. gg— Removable Cylinder Screws, each* b— Steam Valve Stem Forks, each, c— Steam Valve Stem Fork Bolts, each* e— Valve Rod Link Bolts, each- d— Rocker Arm Pins, each. f- Crosshead Link Bolts, each, o — Collar Bolts, each. pp— Brass Steam Cylinder Drain Cocks, eaclW Water Packings, each. Brass Pi.Nton Rods, each. Bra.ss Lined Removable Cylinders, extra, eat Piston Rod Stuffing Q'^nd Bolts, each. Water Cylinder Cap Bonnets, each. Top Valve Caps, each. Valve Cap Clamps, each. In Figs. 103 and 103 are exhibited the outlines of the double acting steam pumo, which is undoubtedly the pattern most thoroughly adapted for feeding steam boilers, as it is equipped for the slowest motion with less risk of stopping on a center. From the drawing with reference letters may be learned the terms applied generally to the parts of all steam pumps: exam- ple: ^^ k " shows the water valve stems, '^ K '^ the water cylinder heads. It may be remarked that nearly all pump makers furnish val- uable printed matter, giving directions as to repairs, and best method of using their particular pumps — especially valuable are their repair sheets in which are given cuts of '^ parts'^ of the pumps. It were well for the steam user and engineer to request such matter from the manufacturers for the special pump they use. Maxims and Instructions, ^ip POINTS RELA.TING TO PUMPS. Blow out the steam pipe tlaorouglily with steam before con- necting it to the engine; otherwise any dirt or rubbish there might be in the pipe will be carried into the steam cylinder, and cut the yalyes and piston. Never change the valve movement of the engine end of the pump. If any of the working parts become loqse, bent or broken, replace them or insert new ones, in precisely the same position as before. Keep the stuffing boxes nearly full of good packing well oiled, and set just tight enough to prevent leakage without excessive friction. Use good oil only, and oil the steam end just before stopping the pump. It is absolutely necessary to have a full supply of water to the pump. If possible avoid the use of valves and elbows in the suction pipe, and see that it is as straight as possible; for bends, valves and elbows materially increase the friction of the water flowing into the pump. See that the suction pipe is not imbedded in sand or mud, but is free and unobstructed. All the pipes leading from the source of supply to the pump must be air-tight, for a very small air-leak will destroy the vacuum, the pump will not fill properly; its motion will be jerky and unsteady, and the engine will be liable to breakage. A suction air chamber (made of a short nipple, a tee, a piece of pipe of a diameter not less than the suction pipe and from two to three feet long, and a cap, screwed upright into the suc- tion pipe close to the pump) is always useful; and where the suction pipe is long, in high lifts, or when the pump is running at high speed, it is a positive necessity. Never take a pump apart before using it. If at any time subsequently the pump should act badly, always examine the pump end first. And if there is any obstruction in the valve, remove it. See that the pump is well packed, and that there are no cracks in pipes or pump, nor any air-leaks. 220 Maxims and Instructions, POINTS RELATING TO PUMPS. In selecting a pump for boiler feeding it is well to have it plenty large enough, and also these other desirable features: tew parts, have no dead points or center, be quiet in operation, economical of steam and repairs, and positive under any press- ure. Granted motion to the piston or plunger, a pump fails because it leaks. There can be no other reason, and the leak should be found and repaired. Leaky valves are common and should be ground. Leaky pistons are not so common, but sometimes occur. Eepairing is the remedy. Leaky plungers are common. They need re-turning. The rod must be straight as far as in contact with the packing. The packing around the plungers is sometimes neglected too long, gets filled with dirt and sedi- ment, and hardens and scores an otherwise perfect rod, and so leaks. The lifting capacity of a pump depends upon proper propor- tion of clearance in the cylinder and valve chamber, to displace- ment of the piston and plunger. An injector is a sample of ^jet jpnmjp — this may either lift or force or both. The most necessary condition to the satisfactory working of the steam pump is a full and steady supply of water. The pipe connections should in no case be smaller than the openings in the pump. The suction lift and delivery pipes should be as straight and smooth on the inside as possible. When the lift is high, or the suction long, a foot valve should be placed on the end of the suction pipe^ and the area of the foot valve should exceed the area of the pipe. The area of the steam and exhaust pipes should in all cases be fully as large as the nipples in the pump to which they are attached. The distance that a pump will lift or draw water, as it is termed, is about 33 feet, because water of one inch area 33 feet weighs 14.7 pounds; but pumps must be in good order to lift 33 feet, and all pipes must be air-tight. Pumps will give better satisfaction lifting from 22 to 25 feet. Maxims and Instructions. 221 POINTS RELATING TO PUMPS. In cold weather open all the cocks and drain plugs to prevent freezing when the pump is not in use. When purchasing a steam pump to supply a steam boiler, one should be selected capable of delivering one cubic foot of water per horse-power per hour. No pump, however good, will lift hot water, because as soon as the air is expelled from the barrel of the pump the vapor occupies the space, destroys the vacuum, and interferes with the supply of water. As a result of all this the pump knocks. When it becomes necessary to pump hot water, the pump should be placed below the supply, so that the water may flow into the valve chamber. The air vessel on the delivery pipe of the steam pump should never be less than five times the area of the water cylinder. There are many things to be considered in locating steam pumps, such as the source from which water is obtained, the point of delivery, and the quantity required in a given time; whether the water is to be lifted or flows to the pump; whether it is to be forced directly into the boiler, or raised into a tank 25, 50 or 100 feet above the pump. The suction chamber is used to prevent pounding when the pump reverses and to enable the pump barrel to fill when the speed is high, Suction is the unbalanced pressure of the air which is at sea level i4TV per inch, or 2096.8 per square foot. When a valve is spoken of in connection with a pump it maj be understood that there may be several valves dividing and performing the functions of one. A simple method of obtaining tight pump- valves consists simply in grooving the valve-sheets and inserting a rubber cord in the grooves. As the valves seat themselves the cord is com- pressed and forms a tight joint. An additional advantage is that it prevents the shock ordinarily produced by rapid closing and prolongs the life of the valve seat. Ti^e rubber cord when worn can be easily and quickly replaced. 222 Maxims and Instructions, CALCULATIONS EELATING TO PUMPS. To find the pressure in pounds per square inch of a column of water, multiply the height of the column in feet by .434. Approximately, we say that every foot elevation is equal to ^ lb. pressure per square inch; this allows for ordinary friction. To find the diameter of a pump cylinder to move a given quantity of water per minute (100 feet of piston being the standard of speed), divide the number of gallons by 4, then extract the square root, and the product will be the diameter in inches of the pump cylinder. To find quantity of water elevated in one minute running at 100 feet of piston speed per minute. Square the diameter of the water cylinder in inches and multiply by 4. Example: capacity of a 5 inch cylinder is desired. The square of the diameter (5 inches) is 25, which, multiplied by 4, gives 100, the number of gallons per minute (approximately). To find the horse power necessary to elevate water to a given height, multiply the weight of the water elevated per minute in lbs. by the height in feet, and divide the product by 33,000 (an allowance should be added for water friction, and a further allowance for loss in steam cylinder, say from 20 to 30 per cent. ). The area of the steam pidon, multiplied by the steam press- ure, gives the total amount of pressure that can be exerted. The area of the ivaier piston, multiplied by the pressure of water per square inch, gives the resistance. A margin must be made between the power and the resistance to move the piston at the required speed — say from 20 to 40 per cent., according to speed and other conditions. To find the capacity of a cylinder in gallons. Multiplying the area in inches by the length of stroke in inches will give the total number of cubic inches: divide this amount by 231 (which is the cubical contents of a U. S. gallon in inches), and product is the capacity in gallons. The temperature 62° E. is the temperature of water used in calculating the specific gravity of bodies, with respect to the gravity or density of water as a basis, or as unity. Maxims and Instructions, 223 STEAM PUMPS. SIDE SECTION FRONT SECTION OOO-GtiOO-QOOO y. 00.00000 o.oboo I ^9^600000 ooqo I oci 0000 000 obo I apoooooooop i o;o 000000 00 Qoooooo 000b oq 00000 00000 o o. o 00 o o o o/> o^ ^. ooQooo 00 06 oOH O 0(5Q.OQj;>OoOO 000000 0000 00 itzii Maxims and Instruction^, STTEFACES AND CAPACITIES OF PIPES. Sizes of Pipes. 2.652 m. 3.299 1 in. in. 1^ in. 5.969 2 in. 2^ in. 9.933 3 in. 10 99 3^ in. 4 in- 4^ in. 5 in. 1. Outside cir- cumferences ot pipes in inches.. 4.136 5.215 7.461 12.56 14.13 15.70 17 47 2. Length of Pipe In feet to give a square foot of outsidf surface 4.53 3.63 2.90 3.30 2.01 1.61 1.33 1.09 .954 .849 7.63 .686 3. Number of square feet of outside surface in ten lineal feet of Pipe 2.21 2.74 3.44 4.34 4.97 6.21 7.53 9.16 10.44 11.78 13.09 16.53 4. Cubic in. of internal capaci- ty in ten lineal feet of pipe 36.5 63.9 103.5 179.5 244.5 402.6 573.9 886.6 1186.4 1527.6 1912.6 2398.8 5. Weight in lbs. of water in ten lineal feet of pipe 1.38 2.31 3.75 6.5 8.8 14.6 20.8 321 43.6 55.4 69 3 86 9 Pipe manufactured from double thick iro.i is called X-strong pipe, and pipe made double the thickness of X-strong is known as XX-strong pipe. Both X-strong and XX-strong pipe are furnished plain ends — no threads, unless specially ordered. The table '^ Data relating to iron pipe " will b3 found espec- ially useful to the engineer and steam fitter. The size of pipes referred to in the table range from -J to 10 inches in diameter. In the successive columns are given the figures for the follow- ing important information: 1. Inside diameter of each size. 2. Outside diameter of each size. . 8. External circumference of each size. 4. Length of pipe per square foot of outside surface, 5. Internal area of each size. 6. External area of each size. 7, Length of pipe containing one cubic foot. 8. Weight per foot of length of pipes. 9. Number of threads per inch of screw. 10. Contents in gallons ( D". S. measure) per foot. 11. Weight of water per foot of length. Maxims and Instructions. H7 DATA Relati2!sG to Iroi^ Pipe. Weight of Water per foot of Length. a 0(^^^oooi-t1'r?coiOTH^iOOloOr^cc»ooo OOOOr-rOiOi>-COT— IOtH'^00»OC0COi--»CiO 1-1 1-1 GoooGOoo(^^ocoooooco OOwOOOOOi-IT^CO'^CDOOO'rrOiCOCOO o*P. T-l rH tH C^ C-C ^ No. of Threads per inch of Screw 2>-0000^'H'T-lrH — rHOOOOOOQOOOOOQOOOOOQOOO C^T-ii-lr-iTHrHrHrHT-l So^ .^4:^^) o5 »-5 ^1^ Length of Pipe con- taining one Cubic Foot. iOiO-X5T-l3:>COT-irOOGOT?OOCC>0 10^ 0(^?cocoi-i-^iOcoO'r^05J>ooG<«oo >o — ^ (7^' CO CO '7'^c6ci ^ rA 000»OJ>t^<:OCii>'-^COTHT— It— 1 CO i> ' ■ * * * r-5 (72 Sy* ^' CO 05 G«it-r-lOOOOrH'OrtJiO-+'^lO?>0 i-i-tH-^OS-T^OO^CO-^OCOCVCOOCOir-QOCO— 1^ ooT-iT-i^£-'7;t-^c50coio::^x>7>-!ti(7?coio iHr-)CO-^£-C5:>'7^»OaiCX)OOOCOOO r-irHi-174COiOCOJ>- Length of Pipe per sq. ft. of Outside Surface. 1 lO^>'^??^-co-^ rHoo-H»ooi»oc5t-JO'!i^'*»o "rHt^OOCOOOt— lTH'7^0:>iO'^CO-7^?>'0'^aiiO •^O':oiocoo:>co0iocooc5:>ao2>'coioo^coco 05^:-0'^co'^^c^>(^^l-lr-^r^ 9 d ® 5;^ H " 5 fS el «3 5 (T^COrH'T^OS-'^iOCriT-lfT^-OCOJ-OOiOCOHHCOCOO ^^-o:(^^lOc^ico^Hcococooi<:ocoo^^-'-HiOCi'-^o --HQ0a5O'^O r^ tH (7^ (^i CO ^* 10 Z> CrJ Csj '^* ?^ CO* t- O CO rHTHrHr-lrH(7i(7/(?^COCO M 2 1 o -::H OOOOCO-^C5COOOiO lO lOCOCOCOCOiT- (§5* r-ir-irHr-i(rOOOiO ♦ The Standard U. S. gallon of 231 cubic inches. 248 Maxims and Instructions, ^mt:liiii!'^^-^m,^^ PIPES AND PIPING. The division of process in the manufacture of pipe, takes place at 1^ inch, \\ inch and smaller sizes heing called butt- welded pipe, and J^ inch and larger sizes being known as lap- welded pipe; thio rule holds good for standard, X-strong and XX-strong. JOmTS OF PIPES AT^D FITTINGS. The accompanjdng illustrations represent certain joints, couplings and connections used in steam and hot water h-ating systems. For many years in the matter of pipe joints there has been little change. The cast-iron hub and spigot joint. Fig. 115, caulked with iron borings, is probably the oldest kind of joint. This is still generally adopted in hct water heating cf a certain class, and was formerly used with low-pressure steam. A fairly regular smooth internal service is obtained, and once made tight is very durable. Cast-iron flanged pipes have also heen a Icng time in use. These joints are made with a wrought-iron ring gasket, wrapped closely with yarn. Fig. 116, which is sometimes dipped in a mixture of red and white lead. It is placed between the flanges, it being of such a diame- ter as to fit within the bolts by which the joint was screwed up and a nest or iron joint, B B, caulked outside the annular gas- ket between the faces of the flanges. The next step in cast-iron pj -^g^ flange pipe joints was the facing or turning up of the flanges and the use of a gasket of rubber, copper, paper or cement, with Fig. 115. Maxims and Instructions, 249 Fig. 117. PIPES AND PIPING. bolt£ for drawing the faces to- gether. These joints for cast iron pipes have not been changed ex- cepting for some classes of work where a lip and recess, Fig. 1 i 7, formed on opposite flanges, whioh |__| makes the internal surfaoes-, smooth and aid in ])reventing the gaskets from being blown out. The introduction of wrought iron \v elded pipes has diminished the use of cast-iron pipes for many purposes, especially in heating apparatus and other pipe systems. Its advantages are lightness, the ease w^ith which various lengths can be obtained and its strength. Inwrought-iron pipe work the general prac- tice in making joints between pipes is a wrought-iron coup- ling, Fig. 118, with tapered threads at both ends. The pipes do not meet at their ends, and a recess of about f inch or more long by the depth of the thickness of the pipes is left at every pipe end. A similar tapered thread is used in con- necting the cast-iron fittings, elbows, tees, etc.. Fig. 119, to the pipe, and a large recess is neces- sary in each fitting to allow for the tapping of the threads. Thus the inside diameter of the fitting is larger by \ inch than the out- side diameter of the pipe, and the internal projection of the thickness of the pipe and that of the thread of the fitting increases materially the friction due to the interior surfaces of pipe and ^'g, 120. $S0 Maxims and Instructions. PIPES AND PIPING. fitting. This class of joint requires care in the tapping of the fittings and in the cutting of tapered threads on the pipen; much trouble is caused by an inaccurately cut thread, as it may throw a line of pipes sev- eral inches out of place and put fittings and joints under undue and irregular strains. The right and left threaded nipple, rig. 119, is used as a finishing connection joint and between fittings. Space equal to the length of the two threads is required between the two fittings to be connected in order to enter the nipple, and one or bcth fittings should be free to move in a straight line when the nipple is being screwed up. To make up this joint time and care are necessary. The Fig. 122. right threaded end on nipple should be first firmly screwed with the tongs or wrench into the right threaded end of fitting, then slacked out and screwed up again by hand until tight, when it is screwed back by hand, at the same time counting the number of threads it has entered by hand. The same is done with the left threaded end of nip- ple and fitting. If the right and left threads of nipple have counted the same number of threads, each thread, when mak- ing the joint up, should enter the fittings at the same time if possible, and particular care must be taken that the fittings are exactly opposite, to facilitate catching on, prevent crossing threads, and that no irregular strain comes on the nipple while being screwed up. In screwing up these nipples the coupling has to be turned with flats on the external surface to fit an internal wrench: m such cases the thread on nipple has one continuous taper. Maxims and instructions. ^5^ PIPES AND PIPING. These special couplings are marked with ribs on the out- side to distinguish them. Fig. 120 represents another joint in wrought-iron piping known as the '^union/^ composed of three pieces and the washer. Unions are also made with ground joints, and the washer dispensed with. Radiator "valves are now generally connected by them, but if the hole m the radiator is not tapped accurately, the union when drawn up will not be tight, or if tight, the valve will not be straight. Fig. 121 shows right and left threaded nipple connecting elbow and tee with wrought-iron pipes. The flange union. Fig. 122, is another joint generally used on wrought-iron pipes above 4 or 5 inches in diameter in mak- ing connections to valves, etc., and on smaller pipes in positions where it is a convenient joint. This joint consists of two cir- cular cast-iron flanges with the requisite number of holes for bolts, and central hole tapped tapered to receive thread of pipe. The abutting faces of the flanges are generally turned and the holding bolts fitted into the holes. STEAM AND HOT WATER HEATING. Fig. 124. The heating by means of pipes through which are conveyed hot water and steam is a science by itself and yet one claiming some degree of familiarity by all engi- neers, steam users, and architects. In practice it requires a knowledge of steam, air and temperatures, of pressure and supply ; a familiarity with heat and heating surfaces and with all contrivances, appliances and devices that enter into the Fig. 123. 2^2 Maxims and Instructions, STEAM AND HOT WATER HEATING, warming and ventilation of buildings. So long as factories, public and private buildings are erected, so long will warming and ventilation keep progress with steam engineering and remain a part of the general mechanical science required of the supervisory and practical engineer. In what is called ilie system of open circulationj a supply main conveys the steam to the radiating surfaces, whence a return main conducts the condensed water either into an open tanh for feeding the hoiJer^ or into a drain to run to waste, the boiler being fed from some other source; the system of what is called closed circulation is carried out either with separate sup* ply and return mains, both of which, extend to the furthest distance to which the heat has to be distributed, or else with a single main, which answers at once for both the supply a'^d the return, either with or without a longitudinal partition inside it for separating the outward current of steam supply from the return current of condensed water. In either case suitable traps have to be provided on the return main,/(9f preserving the steam pressure withiyi the supply main and radiators. These two systems, in any of their modifica- tions, may also be combined, as is most generally done in any extensive warming apparatus. The system of closed circulation requires the boiler to be placed so low as will allow all the return pipes to drain freely back to it above its water-level. This condition has been mod- ified mechanically by the automatic '' trap,^' a device frequently employed for lifting from a lower level, part or all of the con- densed water, and delivering it into the boiler; it is, in fact, a displacement pump. The same result has been attained by draining into a closed tank, placed low enough to accommodate all the return pipes, and made strong enough to stand the full boiler pressure with safety, and then employing a steam pump, either reciprocating or centrif ul, to raise the water from this tank to the proper level for enabling it to flow back into the boiler, the whole of the circulation being closed from communication with the atmosphere. Maxims and Instrttctions, 253 STEAM AND HOT WATER HEATING. Fig. 125. Fig. 126. Mg. 127. There are two systems of steam heating, known as the direct and the indirect system. Direct radiating surfaces embrace all heaters placed within a room or building to warm the air, and are not directly connec- ted with a system of yentilation. Indirect radiation embraces all heating surfaces placed out- side the rooms to be heated, and can only be used in connection with some system of yentilation. For warming by direct radiation, the radiators usually con- sist of coils, composed of f-inch and 1-inch steam pipes, which are arranged in parallel lines and are coupled to branch tees or heads. In a few exceptional cases, radiators of peculiar shapes are specially constructed. In all cases the coils must have either vertical or horizontal elbows of moderate length, for allowing each pipe to expand separately and freely. Sometimes short lengths of pipe are coupled by return-bends, doubling backwards and forwards in several replications one above another, and forming what are called '^'^ return-bend coils,''' and when several of these sections are connected by branch tees into a compact mass of tubing, the whole is known as a '* box- coil.^' Steam and Hot Water heating have long been acknowledged as altogether most practical and economical in every way — and their universal adoption in all the better class of buildings throughout the country is positive proof of their superiority. 2^4 Maxims and Instructions, STEAM AND HOT WATER HEATING. Fig. 128. Fig. 129. Hg. 130. The heat from steam is almost exactly indentical with that from hot water, and few can distinguish between the two sys- tems when properly erected. They are both healthful, economical and satisfactory methods of warming. They give no gas, dust nor smoke ; are automat- ically regulated, and therefore allow of an even and constant temperature throughout the house, whateyer be the condition of the weather outside. The circulation of the steam through the warming pipes is effected in an almost unlimited variety of ways, and the cause producing the circulation throughout the pipes of the warming apparatus is solely the difference of pressure which results from the more or less rapid condensation of the steam in contact with tlie riidiating surfaces. A partial vacuum is formed by this difference of pressure witliin the radiating portions of the apparatus, and the column of steam or of water equivalent to this diminution of pressure, constitutes the effective head producing the flow of steam from the boiler, at the same time the return current of condensed water is determined by the downward inclination of the pipes for the return course. Points Relating to Steam Heating. N"o two pipes should discharge into a T from opposite direc- tions, thus retarding the motion of both or one of the returning currents. This is called ''buttmg'^ and is one of the most Texatious things to encounter in pipe fitting. Maxims and Instructions, 255 POINTS RELATING TO STEAM HEATING. Fig. 131. Fig. 132. Fig. 133. h 11 steam piped rooms should be frequently dusted, cleaned and kept free from accumulation of inflammable material. The use of the air valve is as follows: In generating steam from cold water all the free air is liberated and driven off into the pipe, with the air left in them, all of which is forced up Vj the highest point of the coils or radiators, and compressed equal to the steam pressure following it. Now, by placing a valve or vent at the return end of the pieces to be heated, the air will be driven out by the compression. Why the vent is p] aced at the return is, that the momentum of the steam, it being the lightest body, will pass in the direction of it, falling down into the return as it condenses, thus liberating the air. Otherwise, should the vent not work, and the air is left in the radiator, it will act as an air spriug, and the contents of the pipes left stationary will be the result; no circulation, no heat; and the greater steam pressure put on, the greater the chances are of not getting any heat; and thus a little device, with an o])ening no larger than a fine needle, will start what a ton of pressure would not do in its absence. If the drip and supply pipes are large there is very little dan- ger of freezing, provided suitable precautions are taken to leave tlte pipes clear. They should be blown through, when left, and the steam valve should be closed. There should also be a free cliance for air to escape in all systems of piping. No rule can be given relating to capacity for heating pipes and radiators which do not require to be largely modified by Burroundinfifs. • 2^6 Maxims and Instructions. POINTS RELATING TO STEAM HEaTING. The field of steam-heating would seem to be limitless — in one public building it required recently 480,000 dollars to meet the expenditures in this single line. As an example of warming on an extensive scale may be taken a large office in New York, of which the following are the particulars: Total number of rooms, including halls and vaults . 386 Total area of floor surface sq. ft. 137,370 Total volume of rooms cub. ft. 1,923,590 A second example is furnished by the State Lunatic Asylum at Indianapolis : Length of frontage of building, more than. 2,000 lin. ft. Total volume of rooms 2,574,084 cub. ft. r indirect radiating sur- Warming J face 23,296 Apparatus I Direct 10,804 LTotal 34,100 sq. ft. (Grate area 180 sq. ft. Boilers, ...\ n^ating surface 5,863 sq. ft. The ^'overhead" system of heating with steam pipes has several advantages. 1. The pipes are entirely out of the way. 2. They do not become covered with odds and ends of unused materials. 3. If they leak the drip fixes the exact location of place needed to be repaired. 4. The room occupied overhead cannot be well otherwise utilized, hence in shops the system has proved efficient. But for offices or store rooms the overhead system is not approved of owing to the heat beating down upon the occupants and causing headache. When overhead heating pipes are used, they should not be hung too near the ceiling. If the room be a high one, it is better to hang them below, rather than above, the level of the belts running across tlie room, and they should not be less than three or four feet from the wall. Maxims and Instructions, 257 STEAM HEATING. It is important to protect all woodwork or other inflammable material around steam pipes from immediate contact with them, especially where pipes pass through floors and partitions. A metal thimble should be placed around the steam pipe, and firmly fastened on both sides of the floor, in such a way as to leave an air space around the Fig. 134. steam pipe. For indirect radiating surfaces, the box coils are the forms most used. The chambers or casings for containing them are made either of brickwork, or often of galvanized sheet-iron of Ko. 26 gauge, with folded joints. The coils are suspended freely within the chambers, which are themselves attached to the walls containing the air inlet flues. Besides coils of wrought iron tubes, cast-iron tablets or hollow slabs, having vertical surfaces with projecting studs or ribs, have been extensively used for the radiating surfaces. As the amount of heat given off from the radiator cannot be satisfactorily controlled by throttling the steam supply, it is usual to divide all radiators into sections, each of which can be shut off from the supply and return mains, separately from the rest of the sections. This method of regulation applies to radiators for indirect heating as well as for direct. Vertical pipe coils, constitute a distinctive form of radiator now largely used. In these a number of short upright 1-inch tubes, from 2 feet 8 inches to 2 feet 10 inches long, are screwed into a hollow cast-iron base or box; and are either con- nected together in pairs by return-bends at their upper ends, pr else each tube stands singly with its upper end closed, a^d Maxims and Instructions, POINTS RELATING TO STEAM HEATING. having a hoop iron partition extending up inside it from the bottom to nearly the top. The supply of steam is admitted into the bottom casting; and the steam on entering, being lighter than the air, ascends through one leg of each siphon pipe and descends through the other, while the condensed water trickles down either leg, and with it the displaced air sinks also into the bottom box. For getting rid of the air, a trap is provided, having an outlet controlled by metallic rods; as soon as all the air has escaped and the rods become heated by the presence of unmixed steam, their expansion closes the outlet. A thorough drainage of steam pipes will effectually prevent cracking and pounding noises. The windward side of buildings require more radiating sur- face than does the sheltered side. When floor radiators are used, their location should be deter- mined by circumstances; the best situations are usually near the walls of the room, in front of the windows. The cold air, which always creates an indraft around the window frames, is thus, to some extent, warmed as it passes over the radiators, and also assists in the general circulation. Water of condensation will freeze quicker than water that has not been evaporated, for the reason that it has parted with all its air and is therefore solid. W^hatever the size of the circulating pipes, the supply and drip pipes should be large, to insure good circulation; the drip pipes especially so. This is all the more necessary when the pipes are exposed, or when there is danger of freezing after the steam is shut off. It is important to see that no blisters or ragged pipes go into the return:, and also to make sure that the ends are not *' blurred in'^ with a dull pipe cutter wheel so as to form a place of lodgment for loose mq-tter in the pipe to stop against. Maxims and Instructions, 259 POINTS RELATING TO STEAM HEATING. Fig. 135. Fig. 136. Fig. 137. Experiments recently made on the strength of bent pipes have developed some things not commonly known, or at least not recognized, that is, the strain on the inside of the angles, due to the effort of the in'pcs to straighten themselves under pressure. The problem is one of considerable intricacy, resolv- able, however, by computation, and is a good one for practice. In the experiment referred to, a copper pipe of 6f in. bore, -h in. thick, was used. The angle was 90 degrees, and the legs about 16 in. long from the center. At a pressure of 912 pounds to an inch, the deflection of the pipe was nearly f in., showing an enormous strain on the inner side, in addition to the pressure. Steam valves should be connected in such a manner that the valve closes against the constant steam pressure. Interesting experiments show that the loss by condensation in carrying steam one mile is 5 per cent, of the capacity of the main, and a steam pressure of seventy-five pounds carried in five miles of mains, ending at a point one-half mile from the boiler house only shows a loss of pressure of two pounds. In steam warming it is necessary to bring the water to a boiling point to get any heat whatever: in hot water warming, fl, low temperature will radiate a corresponding amount of beat. 26o Maxims and Instructions, POINTS RELATING TO STEAM HEATING. Never use a valve in putting in a low pressure apparatus if it is possible to get along without it. All the valves or cocks that are actually required in a well-proportioned low pressure apparatus are, a cock to blow off the water and clean out the return pipes, another to turn on the feed water. Of course the safety valves, guage cocks, and those to shut fire regulators and such as are a part of the boiler, are not included in this *^ point.'' The most important thing in connecting the relief to return pipes is, that it should always be carried down below the line, the same as all vertical return pipes. In connecting the reliefs, so that the lower opening can at any time be exposed to the steam, there will be the difficulty of having the steam going in one direction, and the water in another. The relief pipe should ^' tap " the steam at its lowest or most depressed points. It should always be put in at the base of all steam ^^ risers "' taking steam to upper floors. In leaving the boiler with main steam pipe, raise to a height that will allow of one inch fall from the boiler to every ten feet of running steam pipe; this is sufficient, and a greater fall or pitch will cause the condensed water in the pipe to make at times a disagreeable noise or ^^'^ gurgling.'' The flow pipe should never start from the boiler in a hori- zontal direction, as this will cause delay and trouble in the cir- culation. This pipe should always start in a vertical direction, even if it has to proceed horizontally within a short distance from the boiler. Reflection will show that the perfect appa- ratus is one that carries the flow pipe in a direct vertical line to the cylinder or tank; this is never, or but rarely possible, but skill and ingenuity should be exercised to carry the pipes as nearly as possible in this direction. The flow of steam ought not to be fast enough to prevent the water of condensation from returning freely. All the circulat- ing pipes should be lowest at the discharge end, and the incli- Tiation given them shoulcl not be less tlian one foot in fifty. Maxims and Instructions, 261 POINTS RELATING TO STEAM HEATING. Fig. 138. Fig. 139. Fii^c. 140. The general rule is to lay the main pipes from the boiler so that the pipe will drain from the boiler. Where this is done it is necessary to have a drip just before the steam enters the circulation. This drip is connected to a trap, or, if Fig. 141. the condensed water is returned to the boiler, the drip is arranged accordingly. But it is the best practice to lay the main pipe with the low- est part at the boiler, so that the drip will take care of itself, and not require an extra trap, nor interfere with the return .circulation. When steam is turned into cold pipes the water of condensa- tion gets cold after running a short distance, and if it has to go through a small drip pipe full of frost it will probably bo frozen. Then, unless it is followed up with a pail of hot water, the whole arrangement will be frozen and a great many bursted pipes will result. Wheneyer turning steam on in a system of yery cold pipes, only one room should be taken at a time, and a pail of hot water should be handy so that if the pipe becomes obstructed it can be thawed immediately without damage. When pipes become extensively frozen there is nothing to do but take them out and put in now ones. 262 Maxims and Instructions, POINTS RELATING TO STEAM HEATING. The manner in which a temperature too low to start rapid combustion in wood in steam pipes, operates in originating a fire is by first reducing the oxide of iron (rust) to a metallic condi- tion. This is possible only under certain external con- ditions, among them a dry atmosphere. Just as soon as the air is recharged with moisture, the reduced iron is liable to regain, at a hound. Fig. 142. Fig. 143. its lost oxygen, and in doing so hecome red hot. This is the heat that sets the already tindered wood or paper ablaze. Where there is no rust there is no danger from fire with a less than scorching temperature in the pipe or flue. Hence the necessity of keeping steam or hot water fittings in good order. The indirect system of heating is the most expensive to put in; as to the cost of providing nearly double the heating surface in the coils must be added the cost of suitable air boxes, pipes and registers. For a large installation, this is a serious matter, although for office warming the advantages gained on the score of healthfulness and greater efficiency of employees much more than counterbalance the extra expense. One horse power of boiler will approximately heat 6,000 to 10,000 cubic feet in shops, mills and factories — dwellings require only one horse power for from 10,000 to 20,000 cubic feet. From seven to ten square feet of radiating surface can be heated from one square foot of boiler surface, i. e. the heating surface of the boiler and each horse power of boiler will heat 240 to 360 feet of 1 inch pipe. Maxims and Instructions, 26j POINTS RELATING TO STEAM HEAT. The proiession most nearly related to that of steara engineers is the working steam fitters^ occupation. Strictly speaking, the engineer should produce the steam, and it is the steam fitters' place to fix up all the steam pipes and make all the necessary connections: but where the steam plants are small, the engineei maybe steam fitter also: hence the introduction in this work of these *''' Points" which are necessary to be known for the proper care and management of any system of steam or hot water heating. The care and patience, the mental strain and not infrequently the physical torture incident to fitting up a complicated pipe system cannot adequately be set forth in words. It is stated to be a fact, that in high pressure hot water heat- ing the water frequently becomes red hot, pressures of 1000 to 1200 pounds per square inch being reached, and when the cir- culation of the system is defective the pipe becomes yisibly red in the dark. Pipes under work benches should be avoided, unless there is an opening at the back to permit the escape of the heated air, which would otherwise come out at the front. When both exhaust and live steam are used for heating, many engineers prefer to use independent lines of pipe for each, rather than run the risk of interference and waste caused by admitting exhaust and live steam into the same system at the same time. Nevertheless, the advantages gained by being able to increase the heating power of a system in extremely cold weather by utilizing the entire radiating surface for high press- ure steam, are so great that it is probably better so to arrange the system of pipes and connections that this can be done. Double extra heavy pipe (XX) is used for ice and refrigerat- ing machines (see page 246"), as a general rule, makers of this class of machinery obtain but little satisfaction in the use of the ordinary thread joining and use special dies with uniform taper — both for couplings, fianges and threading the pipe itself. They do this to protect their reputation and guarantees. 264 Maxims and Instructions, POINTS RELATING TO STEAM HEATING. Welding toiler and other tubes. — The following is a good way in cases of emprgency and can be done on a common forge: Enlarge one end of the shortest piece, and one end of the long piece make smaller, then telescope the two about f of an inch. Next get an iron shaft as large as will go into the tube and lay across the forge with the tube slipped over it. Block the shaft up so that the tuhe irill hang down from the top of the shaft. By such an arrangement the inside of the tube will be smooth for a scraper. When the tube gets to a welding heat strike on the end of the short piece first, with a heavy hammer, then with a light and broad-faced hammer make the weld- Borax can be used to good advantage, but it is not necessary. The next thing is to test the tube, which can be done in the following manner: Drive a plug in one end of the tube, stand it up on that end, and fill it with water, if it does not leak the job is well done, if a leak exists the welding must be again done. Solid-drawn Iron Tubes : Calculated Bursting and Collapsing Pressures. BUKSTING Pkessure. Collapsing Pkessure. External Internal Diameter. Thickness. Diameter. Per Square Per Square Per Square Per Square Inch of Inch of Inch of Inch of Internal Section of External Section of Surface. Metal. Surface. Metal. Inches. Inch. Inches. Lbs. Tons. Lbs. Tons. n .083 1.084 7700 22.4 6500 21.7 n .083 1.209 6900 22.4 5800 21.3 H .083 1.334 6200 22.4 5200 21.0 If .083 1.584 5300 22.4 4300 20 3 2 .083 1.834 4500 22.4 3700 19.7 2i .095 2.060 4600 22.4 3600 19.0 2i .109 2.282 4800 22.4 3600 18.3 22 .109 2.532 4400 22.4 3100 17.7 3 .120 2.760 4300 22.4 3000 17.0 3i .134 3.232 4200 22.4 2700 15.7 4 .134 3.482 3900 22.4 2400 15.0 4 .134 3.732 3600 2y.4 2100 14.3 4i .134 4.232 3200 22.4 1700 la.o 4| .134 4 482 3000 22.4 1600 12 3 6 .134 4 732 2800 22.4 1400 11.7 H .148 5.204 2800 22.4 1200 10.3 6 5.704 2600 22.4 1000 9.0 Maxims and Instructions, 26^ VENTILATION. The quantity of air for each minute for one person is from four to fifteen feet — and from one-half to one foot should be' allowed for each gas jet or lamp. Heated air cannot be made to enter a room unless means are provided for permitting an equal quantity to escape, and the best places for such exit openings is near the floor. For healthful ventilation the indirect system of steam heat- ing is by far the best yet devised, for it not only warms the room, but insures perfect ventilation as well. In this system, the air for warming the room is introduced through registers, having first been heated by passing over coils of pipe or radia- tors suitably located in the air ducts. There is a large volum'e of pure air constantly entering the room, which must displace and drive out an equal quantity of impure air. This escapes principally around the doers and windows, so tha^t not only is the ventilation effected automatically without the use ot special devices, but all disagreeable indraft of cold air is prevented. One of the cheapest and best methods of ventilation is to have an opening near the floor, opening directly into the flue, or some other outlet especially constructed for it, with hot water or steam pipes in this opening, A moderate degree of heat in these pipes will create a draft, and draw out the bad air. Only a few of these pipes are necessary, and the amount of hot water or steam required to heat them is too small to be worthy of consideration. The use of a small gas-jet, burning continuously, in a pipe or shaft has been found to be a most admirable method of ven- tilating inside rooms, closets and similar places where foul air might collect if not replaced by fresh. The following table exhibits the result of careful experiments made by Mr. Thomas Fletcher, of England, with a vertical flue 6 inches in diameter and 13 feet high: Table. Gas Burnt per Hour. Bpeed of Cur- rent per Minute. TotaJ Air Exhaus- ted per Hour. Air Exhausted per Cubic foot of Gaa Burnt. Temperature at outlet. Kormal sa'Fahr. Cubic Feet. 8 4 8 Feet. 205 245 325 415 Cubic Feet. 2,4b0 2,940 3,900 4,980 Cubic Foot. 2,460 1,470 975 622 82" 92' 110" 137' 266 Maxims and Instructiom, EXHAUST STEAM HEATING. Maxims and Instructions, 26^ VENTILATION. Taking the experiments as a whole, it will be seen that in a flue 6 inches in diameter, the maximum speed of current which Dan be obtained with economy is about 200 feet per minute; and this was realized with a gas consumption of 1 cubic foot per hour — 1 cubic foot of gas removing 2,460 cubic feet of air. It should, however, not be required of any system of heating to more than aid in ventilation. It is the architect's or build- er's performance to so arrange lower and upper openings to drive out the bad air. Heatii^g by Exhaust Steam. There are two methods of warming by steam heat — one with live steam direct from the boiler, and the other with exhaust steam. These two are frequently carried out in combination, and in fact generally so where exhaust steam is used at all for warming. In nearly all manufacturing establishments, office buildings, etc., the exhaust steam produced will very nearly, if not quite supply sufficient exhaust steam to furnish all the heat required for heating the building during average weather, although in extremely cold weather, a certain amount of live steam might be necessary to use in connection with the exhaust to supply the required amount of heat. A simple and convenient device operating upon the suction principle has been found to be most efficient. By this the exhaust steam is drawn almost instantly through the most extensive piping; preventing condensation, freezing, and ham- mering, after which it is condensed and purified, and fed back into the boiler by the means of a reciprocating pump. It is claimed that a given quantity of exhaust steam can be circulated by this vacuum system and uniformly distributed through double the amount of heating pipes than could be accomplished by the same quantity of exhaust steam when forced into the heating system by pressure. Fig. 144 is a well-tried system of heating by exhaust steam in which** 7" represents the steam exhaust pipe, with **6''" showing back pressure valve with weight to adjust amount of back pressure; '^4" '^ V are steam supply pipes to radiators; « 5 w « 5 w ^^Q risers; *' 9 *' ** 9 " are condensation return pipes 268 Ml axims and Instructions, HEATING BY EXHAUST STEAM, from the rtiJiators; '^8^^ is the pressure regulating valve from the boilers. Fig. 144 may also be said to represent the general method of piping used in steam and hot water heating, which is difficult of illustration owing to the fact that each locality where it is used requires a different adaptation. OAEE OF STEAM FITTINGS. Many steam fittings are lost through carelessness, particu- larly in taking down old work, but the great bulk are simply '*lost^' for lack of method in caring for them. This task properly falls upon the engineer, as he usually is entrusted with the selection and ordering of the necessary work. A great eaving in the bill of *' findings ^^ can be effected by proper attention. The same systematic care exercised over the other fittings tools, appliances, oil, fuel, etc., used or consumed in the en' gine and boiler room may be urged with equal emphasis. M and Mill. ^in. lin. l^in. 13^ in. Elbows Tees. Nip- ples. Plugs. Redu- cers. R's and L's. Unions 2iu. coup- lings. Fig. 145. Fig. 145 shows a case for keeping fittings, which will enable one to find any particular piece without a moment's delay. In this admirable arrangement it will be seen that the heavy fittings are all at the bottom, the light ones at the top. In the top row of all, the one-quarter and three-eighth inch fittings are placed, being so small that a partition may be put into that Maxims and Instructions. 26g CARE OF STEAM FITTINGS, row of boxes, and then Lave plenty of room, and giving twice the capacity to that row of pigeon holes. Above this case, which is bnilt of one-inch boards, may be put a set of four cupboards, double doors being fitted to each, and thus making a door over each compartment in the fitting rack. The shelves run through these cupboards from end to 3nd. and are not divi'^ed by vertical partitions. The necessary brass fittings are kept on these shelves, and the doors are secured by good locks. The lightest fittings are placed on the lower shelves in this cupboard, being in greatest demand. TOOLS USED m STEAM FITTING. Fig. 146 represents one form of a pipe cutter which is made to use by hand; cutters are also made for use by power, which are capable of cutting off pipes of immense size. In an engineers outfit of steam fitting tools 2 sets are advisable — one to cut pipe |th inch to 1 inch, and the other to cut 1 to 2 inch pipe. Figs. 147, 148, represent different forms of pipe tongs — the former called '^ chain'* tongs which will readily hold three inch pipe. Fig. 149 represents a steam fitter's vice which will '' take " say, 2|- inch pipe down to -Jth. Fig. 150 shows a set of taps and dies for small bolts and nuts which is ordinarily to be found in a steam fitter's outfit although used very gener- ally by machinists and others. Fig. 151 shows a pair of gas-pliers which are used by steam fitters in g^s pipe jobs. Fig. 152 exhibits the old fashioned alligator wrench. In ice and refrigerating jobs of pipe fitting special tubes are used to assure a niceness of joints and fitting which is not called for in steam and w^-ter service. Fig. 149. 210 Maxims and Instructions, TOOLS USED IN STEAM FITTING. Fig. 147, Fig. 14a COCKS. The first means in the earliest times of steam engi- neering, for opening and shutting the passages in the pipes of steam engines were cocks? and these were all worked by hand and re- quired close attention. A boy named Humphry Potter being in charge of one of the cocks of !N"ewcomer's pumping-engines^ and desir- ing time for play, it is said, managed to fasten the lever- handles of the spigots by means of rods and string to F%- 149. the walking beam of the engine, so that each recurrent motion of the beam effected the change required. This was the first automatic valve-motiou. Maxims and Instructions, 271 TOOLS USED IN STEAM FITTING. Fig. 150. Fig. 151, VALVES. The valve is any de- vice or appliance used to control the flow of p. ^^^ a liquid, vapor or gas, through a pipe, outlet or inlet in any form of vessel. In this sense the definition in- cludes air, gas, steam, and water cocks of any kind. The bellows was probably the first instrument of which they formed a part. No other machine equally ancienfc can be pointed out in which they were required. By far the most important improvement on the primitive bellows cr bag was the admission of air by a separate opening — a contrivance that led to the invention of the valve, one of the most essential elements of steam, of water, as well as pneu- matic machinery. Valves and Cocks. — Generally described, a valve is a lid or cover to an opening, so formed as to open a communication in one direction and close it in another by lifting, turning, or eliding — among the varieties may be classed as, the cock, the slide-valve, the puppet- valve and the clack-valve. A commoij form of this valve is shown in Fig. 139, page 2G1. 2^2 Maxims and Instructions. VALVES AND COCKS. An every day example of a yalve, and almost tlie simplest known, is that of an ordinary pump where the valve opens upward to admit the water and closes downward to prevent its return. A valve has a seat, whether it be a gate or circular valve, and is generally turned by a circular handle fitted to the spindle. Difference letween a coch and valve. — The cock is a valve, but a valve is not a cock; the cock is a conical plug slotted and fitted with a handle for turning the cone-shaped valve, with ita opening in line, or otherwise, with the opening of the pipe. Glohe Valve is a valve enclosed in a globular chamber. Fig. 135. This, like many other valves, takes its name from it& shape. Globe valves, whenever possible, should be placed so that tJib pressure comes under the valve, or at the side, for if the valve should become loose from the stem (which they often do) if the pressure is on top, there would be a total stoppage of the steam. Relief Valve is a valve so arranged that it opens outward when a dangerous pressure or shock occurs; a vahe belonging to the feeding apparatus of a marine engine, through which the water escapes into the hot well when it is shut off from the boiler. Hinged Valves constitute a large class, as for example the butterfly valve, clack-valves, and other forms in which the leaf or plate of the valve is fastened on one side of the valve seat or opening. Valve-hracket is a bracket fitted with a valve. The Valve-chamber is where a pump valve or steam valve operates. Valve-coch, — A form of cock or faucet which is closed b^ dropping of a valve on its seat. Valve-coupUng is a pipe coupling containing a valve. V^lve-seat is the surface upon which a valve rest§. Maxims and Instructions. syj COCKS AND VALVES. Back pressure valves are ball or clack valves in a pipe which instantly assume the seat when a back pressure occurs. They are illustrated in ^^^6/' Fig. 144. Their name signifies their use — to maintain a constant back pressure in heating systems. Ball valve— a, faucet which is opened or closed by means of a ball floating in the water. It constitutes an automatic arrangement for keeping the water at a certain level. Bib-cock — a faucet having a bent-down nozzle. CJiech-valve — a valve placed between the feed pipe and the boiler to prevent the return of the water, etc. Brine-valve — a valve which is opened to allow water saturated with salt to escape. In marine service it is *^ a blow-off valve.'* Ball vidve — a valve occupying a hollow seat. These valvea are raised by the passage of a fluid and descending are closed by gravity. Angle valve is one which forms part of an angle, see Fig. 137. The dovhle-seat valve or double-beat valve presents two out- lets for the water. In the Cornish steam engine this is called the equilibrium-valvey because the pressure on the two is very nearly equalized. Three-way cocTc is one having three positions directing th« fluid in either of three directions. This is illustrated in Fig. 138. The three-way valve is also illustrated en page 259, Fig. 136. Four-tvay coch is one having two separate passages in th« plug and communicating with four pipes. Gate valve— B, valve closed by a gate. This is illustrated in Fig. 140. Swing or straight-way valve — ^this is shown in Fig. 141, page 261. Throttle Valve, — This is the valve used to admit steam to the engine and so termed to distinguish it from the main stop valve located near the boiler — to throttle means to choke — hence the throttling of the steam. Rotary Valves are those in which the disc, or plug, or other device used to close the passage, is made to revolvo for opening or closing, the common stop cock being an illustration. 2y4 Maxims and Instructions, COCKS AND VALVES. Lifting Valves are those in which the full cone or stopper is lifted from the valve seat by pressure from below, the poppet, and safety valves being examples. Pressure regulator valve — this is sometimes called a reducing valve and is illustrated in Figs. 142, 143, on page 262. It is designed to reduce the pressure from a high point in the boiler to a lower one in a system of piping, etc. Usually the smaller valves, not exceeding 1^ inch in diame- ter, are wholly of gun-metal; the larger are commonly made with cast-iron bodies and gun-metal fittings. The smallest valves, from |^ up to -J- inch inclusive, have the disk solid with the spindle, and have an ordinary stuffing-box with external gland. Valves of f inch and upwards have the disk loose from the spindle; up to 3 inch valves the spindles are screwed to work inside the casing; above that size the screwed portion is outside the casing. Above the 3-inch size the nozzles of the cast-iron bodies are generally flanged instead of tapped. STEAM FITTINGS. A few of the principal sorts have been illustrated in this work and still others will be described in the *^ Index'*'' at the close of the work. Fig. 123, page 251, illustrates an elbow with outlet. This is sometimes spelled with the capital L, and again as an ell. Fig. 124 shows a long nipple. Fig. 125, page 253, exhibits a husMngf used to reduce one size pipe in a line to another. Fig. 126 is a cross tee. This is frequently spelled with a capital T. Fig. 127 is a plug — used to stop apertures m plates or pipes. Fig. 128, page 254, illustrates a lock nut. Fig. 129 shows a T, as illustrating the difference oetween a T and a cross T, Fig. 126. Fig. 130 is a coupling. Fig. 131, page 255, represents a reducing coupling* Fig. 132 is an illustration of a pipe uyiion. Fig. 133 is a plain elbow (see also Fig. 123.) Maxims ajid InstrncHons. 275 STEAM PIPE AND BOILER COVERINGS. This subject relates to tlie radiation of heat, which, allows a reference to the laws of heat and tables of radiating power of various substances, as set forth on pages 212, 215. The importance of a protection of exposed surfaces from radiation of heat is now undisputed, and many experiments have determined very closely the relative value of the various nonconducting substances. Table of tlie Condcctikg Power of various substances. Substance. Conducting Power. Substance. Conducting Power. Blotting Paper .274 .314 .323 .418 .523 .531 .568 .636 Wood, across fibre Cork Coke, pulverized India Rubber Wood, with fibre Plaster of Paris Baked Clay .83 Eiderdown Cotton or Wool, any ) density ) " Hemp, Canvas 1.15 1.39 1.37 1.40 Mahogany Dust 3.86 Wood Ashes 4.83 Straw Charcoal Powder Glass Stone. 6.6 13.68 By the above table may be judged the comparative value of different coverings; blotting paper with its confined air, stand- ing at one end of the list, stone at the other. It should be noted that the less the conducting power the better protection against radiation, A non-conducting coating for steam pipes, etc., used for many years with perfect satisfaction, can bo prepared by any steam user. It consists of a mixture of wood sawdust with common starch, used in a state of thick paste. If the surfaces to be covered are well cleaned from all trace of grease, the adherence of the paste is perfect for cither cast or wrought iron; and a thickness of 1 inch will produce the same effect as that of the most costly non-conductors. For copper pipes there should be used a priming coat or two of potter's clay, mixed thin with water and laid on with a brush. The sawdust is sifted to remove too large piecos, and mixed with very thin starch. A mixture of two-thirds of wheat starch with one-third of rye starch is the best for this purpose. It is the common practice to wind string spirally round the pipes to be treated to 2'/6 Maxims and Instructions, PIPE AND BOILER COVERINGS. secure adhesion for the first coat, which is aboufc l-5th of an inch thick. When this sets, a second and a third coat are suc- cessfully applied, and so on until the required thickness is attained. When it is all dry, two or three coats of coal tar, applied with a brush, protect it from the weather. Avery efficient covering may be made as follows: 1, wrap the pipe in asbestos paper — though this may be dispensed with; 2, lay slips of wood lengthways, from 6 to 1*^ according to size of pipe — binding them in position with wire or cord; 3, around the framework thus con«tri7.cted wrap roofing paper, fastening it by paste or twine. J'or flanged pipe, space may be left for access to the bolts, which space should be filled with felt. Use tarred paper— or paint the exterior. While a very efficient non-conductor, hair or wool felt has the disadvantage of becoming soon charred from the heat of steam at high pressure, and sometimes taking fire. The follow- ing table, prepared by Chas. E. Emory, Ph. D., shows the value of various substances, taking wool felt as a unit. Table of Relative Valfe of Nok-Ooj!^dl"ctoks. Non-Conductor. Value. Non-Conductor. Value. Wood Felt 1.000 .833 .715 .680 .676 .633 .553 Loam, dry and open. . Slacked Lime Gas House Carbon Asbestos Coal Ashes. Coke in lumps Air space, undivided .550 Mineral Wool No. 2 Do. with tar, ... .480 .470 Sawdust Mineral Wool No. 1 Charcoal .363 .345 .277 Pine Wood, across fibre . .136 LIKEAR EXPANSION OF STEAM PIPES. Wrought iron is said to expand 1-150,000 of an inch for each degree of heat communicated to it; to make the calculation take the length of the pipe in inches, multiply it by the num- ber of degrees between the normal temperature it is required to attain when heated, and divide this by 150,000. Suppose the pipe is 100 feet long, and its temperature zero, and it is desired to use it to carry steam at 3 00 pounds pressure — equal to a temperature of 338 degrees -multiply 100 feet by 12 to reduce it to inches, and by 338, the difference in temperature; divide Maxims and Insirucizons. ^77 LINEAR EXPANSION OF STEAM PIPES, this by 150,000, and the result will be 2.7 inches, which would be the amount of play that would be required, in this instance, in the expansion joint. rigs. 153 and 154 show a properly designed arrangement of steam connections for a battery of boilers. To the nozzles, risers are attached by means of flanges, and from the upper ends of these 1 I c L 1 B ^pMJfcaii^ H* .*s F F' 1 1 '-. c Bf|«=4 H^ 4 F ^w H' Figs. 153 and 154 nearly so, in order that the valve may not trap water, risers pipes are led horizontal- ly backwards into the main steam pipe. In thishorizontal pipe, the stop valves, one to eachboiler,are placed. These valves should have flanged ends as shown, so that they may be easily removed, if re- pairs become necessary, without dis- turbing any other portion of the piping. Unlike the en- graving, the valve C should be arranged in another posi- tion : the stem should, of course, be horizontal or 2y8 Maxims and tnstruciionL LINEAR EXPANSION OF STEAM PIPES. By this arrangement it will be seen that the movements of the boilers and the piping itself are compensated for by the spring of the pipes. The height of the risers should never be less than three feet, and when there are eight or ten boilers in one battery, they should be, if room permits, six to eight feet high, and the horizontal pipes leading to main steam pipe should be ten or twelve feet or more. THE STEAM LOOP. This is an attachment to a steam boiler, designed to return water of condensation. It invariably consists of three parts, viz.: the ''^ riser, ^' the '^ horizontal, ^^ and the ^"^drop leg," and usually of pipes varying in size from three-fourth inch to two inches. Each part has its special and well defined duties to perform, and their proportions and immediate relations decide and make up the capacity and strength of the system. It is, in fact, nothing but a simple return pipe leading from the source of condensation to the boiler, and, beyond this mere statement, it is hardly possible to explain it; it has, like the injector and the pulsometer pump been called a paradox. The range of application of the steam loop practically covers every requirement for the return of water of condensation. If used in connection with a steam engine, pump, etc., a separa- tor of any simple form is connected in the steam pipe as close as possible to the throttle. From the bottom of the separator the loop is led back to the boiler, and the circulation main- tained by it will dry the steam before it is admitted to the cylinder. There is necessary to its operation a slight fall in tempera- ture at the head of the loop, which is accompanied by a corre- sponding fall in pressure. The water accumulating in the lower end of the loop next to the separator, as soon as it fills the diameter of pipe, is suddenly drawn or forced to the hori- zontal by that difference in pressure. It is immaterial how far the water has to be taken back, or how high it is to be lifted. There is one system now in daily operation lifting the con- densed water over thirty-nine feet, and another lifting it over Maxims and Instructions, 279 THE STEAM LOOP. Bixty-three feet. The strength of the system is increased by length and height, the only limit to its operation being the practicability of erecting the necessary drop leg, the height of which depends on difference in pressures. HORIZONTAL Fig. 155. Fig. 155 is an illustration of its application to a radiating coil. To understand the philosophy of its action, and referring to the illustration, let us assume that all the valyes are open, and full boiler pressure is freely admitted throughout the steam pipe, coil and loop. Now, if the pressure were exactly uniform throughout the whole system, the water in the loop would stand at a on the same level as the water in the boiler. But, as a matter of fact, the pressure is not uniform through- out the system, but steadily reduces from the moment of leav- ing the dome. This reduction of pressure is due in part to condensation, and in part to friction, and although generally small, is always present in some degree. The pressure may be intentionally reduced at the valve on the coil, and reduction necessarily results from condensation within the coil itself. A still further reduction takes place through the loop, so that the lowest pressure in the whole system will bo found at a, the point in the loop furthest from the boiler, reckoned by the flow of steam 28o Maxims and Instructions. THE STEAM LOOP. Now it is known that; water of condensation invariably works towards, and accumulates in, a ^^dead end/' This is due to the fact that, as already shown, the pressure is lower at the *'dead end'' than at any other point in the system, and, as a consequence, there is a constant flow, or sweep, of steam towards the point of least pressure, which flow continues as long as condensation goes on. This sweep of steam carries along with it all the water formed by condensation or contained in the steam, at first in the form of a thin film swept along the inner surface of the loop, and afterwards, when the accumula- tion of water is sufficient, in the form of small sings or pistons of water, which completely fill the pipe at intervals, traveling rapidly towards the dead end. The action of the steam sweep IS vastly more powerful than is usually supposed, and, of course, operates continuously and infallibly to deposit the water in the dead end as fast as accumulated. In practice, water will speedily be carried over by the loop and accumulate in the drop leg until it rises to the level t, which would balance the difference in pressure. As the loop will still continue to bring over water, it follows that as fast as a slug or piston of water is deposited by the steam on the top of the column at h, it overhalances the equilibrium and an equal amount of water is discharged from the hottom of the column through the chech valve into the hoiler. The result of the practical operation of many systems of this ingenious device show advantages as follows: 1. Return of pure water to the boiler and saving the heat contained in said water. 2. Preserving more uniform temperatures, thus avoiding the dangers due to expansion and contraction. 3. Prevention of loss from open drains drips, tanks, etc. 4. Maintaining higher pressure in long lines of piping, in jackets, driers, etc. 5. Enabling engines to start promptly. 6. Saving steam systems from water, thereby reducing lia- bility to accident. Maxims and Instructions, 281 BOILER MAKERS' TOOLS AND MACHINERY. Fig. 156 represents a pair of jack screws, l^hese are invaluable devices for use in boiler- shops, and also in establishments where ponderous ma- chinery has to be shifted or other- wise handled. But few machine tools are used in making steam boilers, and they are generally as follows : Fig. 156. 1st. — The Rolls, operated either by hand levers or power; used for bending the iron or steel plates into circular form. 2d. — A wide power planer for trimming the edges of the sheet perfectly straight and true. 3d. — Heavy Shears for trimming and cutting the plates. 4th. — A Power Punch for making the rivet holes. 5th. — A Disc for making the large holes in the tube sheets to receive the ends of the tubes. 6th. — Rivet heating furnaces and frequently steam riveting machines. The hand tools needed by boiler makers are equally few, consisting of riveting hammers and hammers for striking the chisels, tongs to handle hot rivets, chipping chisels used in trimming the edges of plates, cape chisels for cutting off iron or making holes in the sheets, expanders to set the tubes, and also drift pins to bring the punched sheet exactly in line. Fig. 157 exhibits an improved pattern of the well-known V)ol — dudgeon expander. Fig. 157. 282 Maxims and Instructions. STEAM. Steam is water in a gaseous state ; the gas or vapor of water ; it liquifies under a pressure of 14. 7 and temperature of 212° F. Stemn is a joint production of the intermingling of water and heat. Water is composed of two gases which have neither color nor taste^ and steam is made up of the same two gases with the addition only of that mysterious property called heat by which the water becomes greatly expanded and is rendered invisible. The French have a term for steam which seems appropriate when they call it water-dust. This is what takes place in the formation of steam in a vessel containing water in frte communication with the atmosphere. At first, a vapor is seen to rise that sterns to come from the surface of the liquid, getting more and more dense as the water becomes hotter. Then a tremor of the surface is produced, accompanied by a peculiar noise which has been called the sing- ing of the liquid ; and, finally, bubbles, similar to air bubbles, form in that part of the vessel which is nearest to the fire, then rise to the surface where they burst, giving forth fresh vapor. The curious fact must be here noted that if water be intro- duced into a space entirely void of air, like a vacuum, it vaporizes instantaneously, no matter how hot or cold, so that of an apparent and fluid body there only remains an invisible gas like air. That steam is dry at high pressure is proved by an experi- ment which is very interesting. If a common match head is held in the invisible portion of the steam jet close to the nozzle, it at once lights, and the fact seems convincing as to complete dryness, as the faintest moisture would prevent ignition even at the highest temperature. This experiment proves dryness of the steam at the point of contact, but if throttling exists behind the jet, the steam supplied by the boiler may be in itself wet and dried by wire drawing. Dead steam is the same as exhaust steam. Live steam is steam which has done no work. Dry steam is saturated steam without any admixture of mechanically suspended water. Maxims and Instructions, STEAM. High-pressure steam is commonly understood to be steam used in high-pressure engines. Low-pressure steam is that used at low pressure in condensing engines, heating apparatus, etc., at 15 lbs. to the inch or under. Saturated steam is that in contact with water at the same temperature; saturated steam is always at its condensing point, which is always the boiling point of the water, with which it is in contact; in this it differs from superheated steam. Superheated steam, also called steam-gas, is steam dried with heat applied after it has left the boiler. Total heat of steam is the same as steam heat. Wet steam, steam holding water mechanically suspended, the water being in the form of spray. Specific gravity of steam is .625 as compared to air under the same pressure. The properties which make it so valuable to us are: 1. The ease with which we can condense it. 2. Its great expansive power. 3. The small space in which it shrinks when it is condensed either in a vacuum chamber or the air. A cubic inch of water turned into steam at the pressure of the atmosphere will expand into 1,G69 cubic inches. WATER HAMMER. The fact that steam piping methods have not kept pace with the demands of higher pressures and modern practice is evi- denced by the increasing number of accidents from the failure of pipes and fittings. There has not been, for the rapid increase of pressure used, a proportionate increase in strength of flanges, number and size of bolts used, and more generous provision for expansion and contraction. Valves and fittings also require greater attention in their design, construction and manipulation. 284 Maxims and Instructions. WATER HAMMER. It is well known that tlie presence of condensed, water in pipes is a source of danger, but little is known of what exactly goes on in the pipe. We have the incompressible liquid, the expansive gas, and the tube with a '^ dead head '^ or dead end as it is called, or where the end of the pipe is closed. Seeing that the tube or pipe is capable of withstanding all the pressure that the steam can give, it is difficult to acc(iunt for the tre- mendous repelling force, which is, undoubtedly, brought into operation in explosions or ruptures of steam pipes carrying what are now comparatively low pressures. The cause of the bursting is undoubtedly water hammer or water ram, which accompanies large, long steam pipes, filled with condensed water. If steam be blown into a large inclined pipe full of water, it will rise by difference of gravity to the top of the pipe, forming a bubble; when condensation takes place, the water below the bubble will rush up to fill the vacuum, giving a How directly against the side of the pipe. As the water still further recedes the bubble will get larger, and move farther and farther up the pipe, the blow each time increasing in intensity, for the reason that the steam has passed a larger mass of water, which is forced forward by the incoming steam to fill the vacuum. The maxi- mum effect generally takes place at a ^^dead end.'* In fact, under certain conditions, a more forcible blow ia struck when the end of the pipe is open, as, for instance, when a pipe crowned upward is filled with water, one end being open and the steam introduced at the other. ' A bubble will in due time be formed at the top of the crown, when the water will be forced in by atmospheric pressure from one end and by steam pressure from the other, and the meeting of the two columns frequently ruptures the pipe. The remedy for this is simple, the pipes must be properly located so as to drain themselves or be drained by rightly loca- ted drip cocks. The drip should be the other side of the throttle valve, and if steam is left on over night this valve should be left open enough to drain out all the water. Maxims and Instructions, 28^ HAZARDS OF THE BOILER ROOM. Where there is great power, there is great danger. When the pressure is increased, the danger is increased. When the pressure is increased, diligence, care and scrutiny should be increased. During the twelve years between 1879 and 1891 there were recorded 2,159 boiler explosions; these resulted in the death of Z,\'l'6 persons, and in more or less serious injury to 4,352 others. Besides these there were innumerable other accidents during the same period, caused by other means, which empha- sizes the gravity of this cautionary '' chapter of accidents." Every boiler constructed of riveted plate and carrying a high, head of steam, holds in constant abeyance, through the strength of a disruptive shell, a force, more destructive in its escaping violence than burning gunpowder. To the casual observer there is no evidence of this; and it is only when a rupture takes place of such a character as to liberate on the instant the entire contents of the boiler that we get a real demonstration of the fact. Unfortunately a steam boiler never grows stronger, but deteriorates with every day's age and labor, subjected, as it is, to all sorts of weakening influences; and fractures often occur, which, if not at once repaired, would speedily reduce the strength of the boiler to the point of explosion. In the case of a boiler we have, first, a vessel of certain strength, to resist strains; and second, expansive steam and water contained therein. It must be plain that if the strength of the vessel is superior to the internal pressure there can be no explosion, and also, on the contrary, if we allow the pressure to go above the strength of the vessel, that there must be a rup- turing and an explosion, but it will be in the weakest place of that vessel. Experiments by the most eminent men have failed to discover any mysterious gas formed by boiling water, or by any mixture 286 Maxims arid In. tructions, STEAM BOILER EXPLOSIONS. of air and water. Boilers have been built for the express pur- pose of trying to explode them under various conditions of high and low water, and nothing in regard to the sudden generation of any gas has been discovered. Again, disastrous explosions that have occurred have been of vessels that contained no water and were not in contact with fire, flame or heated air, but were supplied by steam some distance away. The destructive efforts of the vaporization attendant upon explosions seem to be due to the subsequent expansion of the steam so foriied, rather than to the intensity of its pressure; low or high steam alone has very little to do with boiler explo- sions; nor high or low water necessarily. The one great cause of boiler explosion is the inability of the boiler to withstand the pressure to which it is subjected at the time, and this may be brought about by any one of the follow- ing causes, viz. ; 1. Bad design, in which the boiler may not be properly strengthened by stays and braces; deficient water space, pre- venting the proper circulation of the water, 2. Bad workmanship, caused by the punching and riveting being done by unskilled workmen. 3. Bad material, blisters, lamination, and the adhesion of sand or cindeis in the rolling of the plate. 4. By excessive pressure, caused by the recklessness of the engineer, or by defective steam-gauges or inoperative safety- valves. 5. Overheating of the plates, caused by shortness of water. When water is poured on red-hot surfaces it does nut touch the surface, but remains in the spheroidal state at a little distance from it, being apparently surrounded by an atmosphere of steam. It assumes this state above 340'^; when the tempera- ture falls to about 288° it touches the surface and commences boiling. Maxims and Instructions, 28'^ STEAM BOILER EXPLOSIONS. 6. By accumulation of scale, mud, or other deposit, which prevents the water gaining access to the iron. This causes the seams to leak, the crown-sheet to bulge or come down. One is unable to find any proof that boilers do generally explode at about starting time, nor is that statement, to the best of information, founded on any basis of fact, but was first affirmed by parties who had designed a boiler especially arranged to avoid that imaginary danger. No one supposes that inspection will absolutely prevent all explosions; but rigid inspection will discover defects that might end in explosion. Low water is dangerous from the fact that it leaves parts of the boiler to be overheated and the strength of iron rapidly decreases in such a case. In fact, an explosion caused by low water might be expected to be less disastrous than if the water was higher, other conditions being equal, from the fact of there being less water at a high temperature ready to flash into steam ali the moment of liberation. Testing new boilers under steam pressure is both dangerous and unwise — the hot water expansion test is just as efficient, less cosily and safe in every respect — hence, there is no occasion for a steam test. A manufacturer was testing a boiler in the way mentioned when a rivet in a brace blew out, and the con- tents of the bciler rushed out, striking a man in the face, and parboiling him from head to foot. Another who was inspect- ing the boiler, was struck on the head and enveloped in steam and water; another was also scalded from the shoulders down; another was injured about the arms; a fifth man was scalded a ad severely injured about the back. The apartment was so filled with steam that the victims could not be rescued until all tlie damage mentioned had been done to them. Danger from exploding steam pipes is greater than supposed. An inspe:tor in a pipe works was testing a tube by means of a double-action hydraulic pump; the pipe suddenly burst with 288 Maxims and Instructions » HAZiVKDS OF THE BOILER ROOM. the pressure of 5000 pounds to the square inch, and the water striking the unfortunate man on his face, he was killed on the spot. There is a tendency on the part of engineers to trust too implicitly in their steam gauges. These are usually the only resort for determining the steam pressure under which the boiler may be working. But the best gauges are liable to err, and after long use to require a re-adjustment. It is fortunate, however, that the error is usually upon the safe side of indicat- ing more than the actual pressure. Any boiler that has been standing idle for a few weeks or months is a dangerous thing to enter, and no one should attempt it until it has been thoroughly ventilated by taking off all the man-hole and hand-hole plates and throwing water into it. This is due to the presence of a gas which is generated from the refuse and mud, or scale, which, to a greater or less degree, remains in all boilers. Contact with fire is certain to result in an explosion. Not long since a locomotive was in a roundhouse, where it had been waiting some weeks for repairs. Some of the tubes were split and a man was pulling them out. He had only removed one or two when, putting in his lamp to see what remained, there was a fearful explosion which shook the shop. There are many other places which are unsafe to enter when they have been long closed, such as wells, pits of any kind, and tanks. Precisely what the nature of the gas is no one seems to know, but it is assuredly settled that a man who goes into it- with a light seldom comes out unharmed. The gas most likely to fill idle boilers in cities is sewer gas, that gets in through the blow-off pipe, which is left open and generally connects with the sewer; hence, the connection with the sewer by the blow-off pipes should receive attention. Boilers are sometimes unexpectedly emptied of their contents by the operation of the principle of the syphon; a boiler is so piped that a column of water may be so formed as to draw out of the boiler its entire contents. Danger ensues if this is done while the boiler is being fired. Maxims and Instructions, 28g rUEL OIL. The long experimental use of petroleum or natural oil as a combustible has devel- oped but one serious objection to its wide spread and popular adoption; that objec- tion arises from its liability to ignite and cause destruction by fire; but The Hazards of Fuel Oil may be remedied by the observance of the follow- ing rules adopted by a certain fire under- writers^ association: *' Vault to be located so that the oil it contains can burn with- out endangering property and have a capacity sufficient tc hold twice the entire quantity of oil the tanks within can contain. Location of vauU to be left to the approval of the Superin- tendent of Surveys. Distance from any property to be regu- lated by size of tank. Vaults to be underground, built of brick, sides and ends to be at least 16 inches thick and to be made water tight with hydraulic cement ; bottom to be water tight, concrete, dished toward centre, and inclined to one end so as to drain all over- flow or seepage to that end, said incline to be to the end oppo- site to that from which the tank is to be tapped ; top to be supported with heavy iron I-beams, with arches of solid brick sprung from one beam to its neighbors, and to have at least twelve inches of dirt over the masonry. Vault to be accessible by one or more large man-holes, which, when not in use, are to be kept locked by a large padlock of three or more tumblers, key to be held by some responsible party. A trough must run from one end of the vault to the other, directly under each tank, and in the same direction as the tank or tanks. Tank to be of boiler iron or steel, at least 3-16 inch in thick- ness, to be cold riveted^ rivets to be not less thai; 3-8 inch ii; 2 go Maxims and Instructions. RULES RELATING TO USE OF FUEL OIL. diameter and not over 1 inch apart between centres; the entire outer surface of tank to have two good coats of coal tar or min- eral paint before the tank is placed in position. No tank shall be over 8 feet in diameter by 25 in length, nor shall any vault have over two tanks. When tank is set, the bottom of the tank must be 3 inches above the concrete floor of the vault, and must be in saddles of masonry not less than twelve inches in thickness, built from the concrete floor of the vault, said saddles not to be more than 3 feet apart between centres, and laid in hydraulic cement, with an opening through centre for drainage. Tank must incline 1 inch per 10 feet in length toward the end from which it is to be tapped, said incline of the tank to be opposite to the incline at the bottom of the vault. The filling pipe, man-hole, telltale or indicator, pump sup- ply connection, steam connection, overflow pipe and ventila- ting pipes, where they connect with tank, must be made petroleum tight by the use of litharge and glycerine cement. Flanges to make tank f inch in thickness to be riveted on the inside so as to furnish a satisfactory joint where connec- tions are made, must be used. Filling pipe connection must have gas-tight valve between the tank and hose coupling, which must be kept closed and locked unless the tank is being filled. Each tank must have ventilating pipes at least \\ inches in diameter, one of which must connect with one end of the top of the tank and must be in the form of an inverted J, a union to be placed in pipe just beloAV the bend, within which shall be placed a diaphragm of fine wire gauze ; the other ventilating pipe must be at the other end of the top of the tank and must be con- ducted to the inside of the smoke stack or into the open air at least 10 feet above the surface, so that all the gases that form in the tank will be constantly changed. Tank must have indicator to show height of oil in tank at all times, said indicator to be so arranged as to allow no es- capement of gases from tank. Maxims and Instructions, 2gi RULES RELATING TO USE OF FUEL OIL. All pipes leading from the tank to the pump or pfacfe of burning, must incline toward the tank, and have a fall of at least 2 feet from bottom of stand pipe to top of storage tank, and must be so constructed that the feed pipe from stand pipe to burners shall be entirely above burners, so that no pockets of oil can be formed in any one of the pipes between the mam tank, stand pipe, oil pump or place of burning. The vault shall be air tight as near as possible, and must have tvro ventilating pipes of iron of 4 inches diameter, both inlet and outlet pipes to reach within 6 inches of the bottom of the vault, the outlet ventilating pipe to rise above surface 8 feet, and the inlet ventilating pipe to rise above surface 6 feet. Syphon to be arranged so as carry out any seepage or leak- age into the vault, and discharge same upon the ground, where its burning would not endanger surrounding property.'* The following are a part of the rules adopted hy the German Government to prevent accidents in mills and factories: they are equally applicalle in all places where steam power is used: *' All work on transmissions, especially the cleaning and lub- ricating of shafts, bearings and pulleys, as well as the binding, lacing, shipping and unshipping of belts, must be performed only by men especially instructed in or charged with such labors. Females and boys are not permitted to do this work. The lacing, binding or packing of belts, if they lie upon either shafting or pulleys during the operation, must be strictly prohibited. Daring the lacing and connecting of belts, strict attention is to be paid to their removal from revolving parts, either by hanging them upon a hook fastened to the ceiling, or in any other practical manner ; the same applies to, smaller belts which are occasionally unshipped and run idle. While the shafts are in motion they are to be lubricated, or the lubricating devices examined only when observing the fol- lowing rules : (1) The person performing this labor must either do it while standing upon the floor, pr by the use of (2) firmly 2g2 Maxims and Instructions, GOVERNMENT RULES TO PREVENT ACCIDENTS. located stands on steps, especially constructed for the purpose, so as to afford a good and substantial footing for the workman ; (3) firmly constructed sliding ladders, running on bars ; (4) sufficiently high and strong ladders, especially constructed for this purpose, which by appropriate safeguards (hooks above oi' iron points below) afford security against slipping. All shaft bearings are to be provided with automatic lubrica- ting apparatus. Only after the engineer has given the well -understood signal, plainly audible in the workrooms, is the engine to be started. If any work other than lubricating and cleaning of the shaft- ing is to be performed while the engine is standing idle, the engineer is to be notified of it, and in what room or place such work is going on, and he must then allow the engine to remain idle until he has been informed by proper parties that the work is finished. Plainly yisible and easy accessible alarm apparatus shall be located at proper places in the workrooms, to be used in case of accident to signal to the engineer to stop the engine at once. All projecting wedges, Tceys, set-screws, nuts, grooves or other parts of machinery, havhig sharp edges, shall he substantially covered. All belts or ropes which pass from the shafting of one story to that of another shall be guarded by fencing or casing of wood, sheet-iron or wire netting four feet, 6 inches high. The belts passing from shafting in the story underneath and actuating machinery in the room overhead, thereby passing through the ceiling must be enclosed with proper casing or netting corresponding in heigth from the floor to the construc- tion of the machine. When the construction of the machine does not admit of the introduction of casing, then, at least, the opening in the floor through which the belt or rope passes §hould be inclosccl with a low casing at least four inches high. Maxims and Instructions, 2gj GOVERNMENT RULES TO PREVENT ACCIDENTS. Fixed shafts^ as well as ordinary shafts, pulleys and fly- wheels, running at a little height above the floor, and being svithin the locality where work is performed, shall be securely covered.'^ The most simple and efficient of all substances for fire ex- tinguishment is sulphur. This, by heat, absorbs oxygen and forms sulphurous acid, the fumes of which are much heavier tiaan the air. The quantity required would be small. Besides sulphur, which gives every satisfaction, both in its effects and ficom its low cost, we find a similar property in another active and cheap substance, ammonia. An automatic sulphur extin- guishing apparatus can be make of various forms. If night repairs, Sunday, or any other work which requires t!ie use of artificial light (especially portable lights of any kind) becomes necessary, more than one man should be employed, one of whom should be capable of starting the engine or pump i)istantly in case of fire. In guarding against explosion it is conceded that the main r-^liance is to have the boiler made strong enough to stand both t'le regular load or any unexpected strain caused by the stop- f age of the engine ; it is also the tendency of the times to p roceed towards higher and higher figures in steam pressure, until now it is not nnfrequent to see 150 lbs. to the square inch indicated by the gauge ; the larger the boiler, also, the more economically it can be run and this, as in the two cases before cited, requires extra precautions in building the boiler with great regard to strength in every part The following rules posted in a certain . factory aremost excellent for their directness. ^^ Wear close-fitting clothes ; have a blouse or jacket to button close around the waist and body ; have sleeves to fit arms C/iosely as far up as the elbow ; never wear a coat around machinery ; never approach a pair of gears or pulley from the driving side ; never attempt to save time by potting, or trying t\) pot on any fast-moving belts without slacking up or stopping entirel}^ to do it. Never allow an inexperienced person to go through the mills without an attendant ; never allow a woman 294 Maxims and Instructions. FACTORY RULES FOR PREVENTION OF ACCIDENT, to go through a mill, no matter how many attendants, while in motion ; noTcr attempt to go through the mill in the dark, you may forget the exact location of some dangerous object and seek to avoid it, but it is still there, noiselessly waiting a chance to wreck you ; never allow any dangerous place fco go unguarded ; keep your eye open while oiling ; never relax youi vigilance for an instant, it may cost you your life. If you feel a gentle tug on your clothes, grab, and grab quick, anjrthing you can cling to, and don't let go till after the clothes do.'^ WATEK CIRCULATION. Water consists of an innumerable quantity of extremely minute particles called molecules. These particles have the property of being able to glide over, under, and to and from each other almost without resistance or friction. When water is heated in a boiler the action that takes place is this: As the heat is applied, the particles nearest the heated surfaces be- come expanded or swollen, and are so rendered lighter (bulk for bulk) than the colder parti- cles, they are therefore com- pelled to rise to the highest point in the boiler. This upward action is vividly shown by the illustration on page 242, and by Fig. 158, where the warmer particles are ascending and the cooler ones are descending by a process which is endless so long as heat is applied to the lower part of the containing vessel. The cause of circulation is the result of an immutable law of nature (the law of gravitation), and is so simple that with i*]aaaaa *' i I f $ k k i\ ^ i f /i. 1^ i k k k k i ¥ If I i\ k Sl« «flli im Fig. 158. Maxims and Instructions. 2g^ WATER CIRCULATION, moderate care in its manipulation failures in arranging steam heating apparatus arc noxt to impossible. A very slight ex- perience suffices to show that a pipe taken froji the top of a boiler and given a direct or gradual rise to the point farthest from the boiler, and then returned and connected into it at the bottom, will upon the application of heat, cause the water to circulate. It is not necessary that the water should boil or even approach boiling point, to cause circulation, as in a properly constructed apparatus the circulation commences soon after the heat is applied end immediately the temperature is raised in the boiler. It is a very common error to su;ipose that the circulation commences in the flow or up pipe, whereas it is just the reverse. The circulation is caused by the water m the return pipe andean be described as a stream of heated particles flowing up one pipe from the boiler and a stream of cooler par- ticles flowing down another pipe into the boiler; or it might be described as a means of automatically transporting heated water from the lower to the upper parts of a building, and pro- viding a down flow of cold water to the boiler to be heated in turn. Those having in charge the erection of hot-water systems for heating buildings, will do well to remember that the circulation they expect depends entirely upon the expansion of particles when heated, and that they must avoid as much as possible friction, exposure of flow pipes to very low temperature, and frequent or numerous short bends. When properly arranged the action of ^' the steam loop " is a very good illustration of the circulation of hot water and Bteam; the flow is continuous, rapid and positive. Note. — When the steam loop is properly connected, the stop valve at the boiler should always be left open and full pressure maintained in the steam pipe over night or over Sunday. The loop will keep up a powerful circulation, returning all water to the boiler as fast as condensed. On starting up in the morn- ing, it is only necessary to open the waste cocks and blow out what little water may have condensed in the cylinders them- selves. The throttle may then be opened and the engine started with the steam as dry as if it had been running continuouslyo 2g6 Maxims and Instructions, CHIMNEYS AND DRAUGHT. Draught, in cliimneys, is caused by the difference between the weight of the air outside and that inside the chimney. This difference in weight is produced by diff'erence in heat. Now, heated air has a strong tendency to rise above cool air and a very slight difference will cause an upward flow of the heated particles, and the hotter the air, the brisker the flow. As these particles ascend it leaves a space which the cooler air eagerly hastens to fill; in the boiler furnace, the hot air push- ing its way up the chimney, is replaced through the grate bars with cool, fresh air. It is the mingling of this fresh air with the combustibles that produces heat, and the power of the draught is absolutely necessary to the reliable operation of the furnace. An excess of draught can be corrected by the use of a damper or even by the closing of the ash pit doors, but no more unhappy position for an engineer can be imagined than a deficiency of draught. This lack is produced by, 1st, too little area in the chimney flue; 2d, by too low a chimney; 3d, by obstructions to the flow of the gases; 4th, by the overtopping of the chimney by adja- cent buildings, hills or tree tops. There are other causes of failure which practice develops; hence, the draught of a new chimney is very often an uncertain thing until every-day trial demonstrates its action. The draught of steam boilers and other furnaces should be regulated below the grate and not in the chimney. The ash pit door should be capable of being closed air tight, and the damper in the chimney should be kept wide open at all times unless it is absolutely necessary to have the area of the chimney reduced in order to prevent the gases from escaping too fast to make steam. When two flues enter a larger one at right angles to it, oppo- site each other, as is frequently the case where there is a large number of boilers in a battery, and the chimney is placed near the center of the battery, (he main flue should always have a division plate in its center oetween the two entering flues to give direction to the incoming currents of gases, and prevent Maxims and Instructions, Sgj CHIMNEYS AND DRAUGHTo their ''butting/* as it may be termed. The same thing should always be doue where two horizontal flues enter a chim- ney at the same height at opposite sides. In stationary boilers the chimney area should be one-fifth greater than the combined area of all the tubes or flueSo For marine boilers the rule is to allow fourteen square inches of chimney area for each nominal horse power. The draft of a chimney is usually measured in inches oJ water. The arrangement most commonly made use of for this purpose consists of a U-shaped glass tube connected by rubber tir.bmg, iron pipe, or other arrangement, with some part of the chimney in such a way that the draft will produce a difference o\ level of water in the two legs of the bent glass tube. The " Locomotive" suggests that the unit for chimney con- st ruction should be a flue 81 feet high above the level of the grates, having an area equal to the collective area of the tubes oi all the boilers leading to it, the boilers being of the ordinary horizontal return tubular type, having about 1 square foot of heating surface to 45 square feet of heating surface. Note the above conditions, and, in case of changing the above p''oportions, it should be observed that the draught power of cliimneys is proportional to the square root of the height, so we YD ay reduce its area below the collective area of the boiler tubes in the same proportion that the square root of its height exceeds the square root ofS\, For example, suppose we have to design a chimney for ten boilers, 66 in. in diameter, each having 72 tubes, 3| in. in diameter, what would be its proportion. The collective area of the 720 3|- in. tubes would be 6,017 square inches, and if the chimney is to be but 81 feet high, it should have this area, which would require a flue 6 ft. 5J iuo square. But, suppose, for some reason, it is decided to have a chimney 150 feet in height, instead of 81 feet. The square root of 150 is 12|; the square root of 81 is 9; and we reduce the areaof the chimney by the following proportion: 12.25: 9 — 6,017: 4,420 square inches, which would be the proper area, and would call for a chimney 5 ft. 6 in„ square, and similarly if any other height were decided upon. 2g8 Maxims and Instructions, PLUMBING. The art of working in lead is older than the pyramids. For thousands of years hydraulics and plumbing as an occu- pation engaged the principal attention of engineers. King David used lead pipe, so did Archimedes; the terraces and gar- dens of Babylon were supplied with water through leaden pi p c s. Steam fitting, with galvanized pipe and an elaborate system of connec- tions and devices is a new department of mechanism — almost of the present generation — and at first sight would seem aLle soon to supercede lead piping of all kinds, but it is safe to say that nothing can ever take the place of lead, for this admirable metal can be made to answer where no other material can be worked; for instance, lead pipe can be made to conform to any angle or ob- struction where no other system of piping will. Hence, plumbing as a useful and ornamental art will never go out of date, and engi)ieors of every branch will do well to study its principles and methods so as to meet the ever-recurring and perplexing questions connected with sewerage, water supply, etc. Every engineer should at least know how 1, to join lead pipe — to make a *^wipe joint, ^' — as in a hundred emergencies this knowledge will be of worth. 2, how to make a temporary stopping of leaks; 3, how to bend pipe with sand or springs; 4, how to ''back air pipes'' from sinks; 5, how to use force pumps; 6, how to arrange the circulating pipes in hot-water boilers; 7, how to make solder; 8, how to repair valves, etc., etc. Maxims and Instructions, 2gg PIPING AND DRAINAGE. The three illustrations on jiage 298 are designed to represent traps set in lead pipe and show vividly the difference between this material and iron piping. Lead is one of the elementary substances of which the world is formed; it ranks with gold, silver, tin, etc., in being an unmixed metal. It melts at about 617° Fahrenheit, and is, bulk for bulk, lliV heavier than water (gold being ITtV heavier and wrought iron 7fo heavier). The tenacity of lead is extremely low, a wire xVth of an inch breaks with a weight of Fig. 159, ^v^'--^?' «.\*.*x^ 28 lbs. ; in comparison, its tenacity is only one-twentieth that of iron; it is so soft that it may be scratched with the thumb nail. If a very strong heat is applied lead boils and evaporates; it transmits heat very slowly; of seven common metals it is the worst conductor, therefore it is good for hot water pipes. Mixed with a sufficient quantity of quicksilver it remains liquid. An advantage to be found in the use of lead is its durability and comparative freedom from repairs. In London, soil and drain water pipes which have been fixc^d 3C0 to 500 years are as 30O Maxims and Instructions, PIPING AND DRAINAGE. good now iS the day they were first made — while iron pipe cannot be expected to last over 10 or 20 years or 30 at the utmost. Fig. ;I59 represents the general system of house piping and drainage applicable also to shops, public buildings, etc. A exhibits the drain or sewer. A-C represents the sewer connec- tion, so called with a running trap, B. ^' C " at the end of the lower pipe exhibits a soil pipe elbow, with hand hule for clean- ing out closed by a screw plug. This drain should have a regular fall or inclination and this elbow provides for that. C-D shows the rain water leader (conductor.) E and F is a soil pipe 3, 4, 5, or 6 inches in diameter. Nota, pipes draining water closets are called ^^soil pipes ^'; those draining other fixtures '^ waste pipes.'' N and represent water closet flanges; F and H are roof connections; L exhibits double and single Y branches to receive waste-pipes from baths, bowls, or sinks. The plumber makes this connection, always trapping the lead waste-pipe and then soldering it to a trass nipple. LEAD PIPE JOINTS. Fig. 160. It has been remarked that after learning how to make '^a wipe joint," everything is easy relating to the plumber's trade; hence, the importance of the following directions. To learn the art, previous practice with short pieces of pipe is recommended. This trial piece can be clamped as shown in Fig. 160 and used over and over until practice has been had. There are many names for the process of lead joint-making, such as the flow-joint, the ribbon joint, the blown joint, the astragal joint, etc., to express the different positions and uses Maxims and Instructions, joi LEAD PIPE JOINTS, for which they are needed, but in the main they are made as follows : 1. The lead pipe to be joined is sawn square off with the proper toothed saw — attention being paid to making the end absolutely true, across the pipe. 2. One end of the pipe to be joined is first opened by driving in a wooden wedge, shaped like a plumb-bob, called the '^Hurn pin," Care should be exercised at this time not to split the end, i inch opening is usually enough, which leaves the pipe as shown at D, Fig. IGl. Now, clean the internal part of the joint all around the part required for soldering — this cleaning can be done with the plumber^s shave hook or with a pocket knife. To complete this preparation " touch " the part with grease from a tallow candle. 3. Kext is the preparation of the male part of the joint. This must be rasp-filed down to fit the enlarged opening. It is important to have a good fit throughout; hence, inside the enlarged opening must be also rasp-filed and the two surfaces to come nicely together before the solder is applied. 4. At this stage a paste called ^'plumber^s soil'' must be applied outside 3 inches from the end of each piece of pipe; this is shown by the line E E in Eig. 161, also at A B, Eig. 160; the line of the soiling should be very even and true in order to assure a workmanlike job and the soiling put on as before stated, 3 ^0 5 inches heyond the solder line on each side. As the melting point of lead is 612 degrees or thereabouts, it is necessary to have solder melt at a lower temperature, and that made under the rule given will melt at 410 to 475 degrees. No tool to a plumber is more important than the cloth used in joint making. To make it, take a piece of new mole skin or fustian, of moderate thickness, 12 inches long by 9 inches wide, fold it up one side 4 inches; then 4 inches again, and again 4 inches; then fold it in the middle, which will make your cloth 4x4^ inches, and of 6 thickness. After this is done, sew up the ragged ends to keep it from opening. Then pour a little hot tallow on one side and the cloth is ready for use. In Eig. 160-a is shown, H, a hand holding the cloth in the process of ''wiping the joint/' whinh will now be described. ^02 Maxims and Instructions, LEA.D PIPE JOINTS. First place a small piece of paper under the joint to catch the surplus solder D and begin soldering as follows: Take the felt F in the right hand and with it hold the ladle three parts full of solder. To see that it is not too hot hold your hand within 2 inches or so of the solder; if it quickly burns your hand it ia too hot; if you can only just hold your hand this distance, use it; but if you cannot feel the heat, the solder is too cold. When you begin to pour your solder upon the joint do ii very lightly and not too much at a time in one place, but keep the ladle moving backward and forward, pouring from E to J, first on one side of the joint to the other and from end to end. Pour also an inch or two up the soiling, as shown at E to make the pipe of proper temperature, i. e., to the same heat as the solder. The further, in reason, the heat is run or taken along the pipe, the better the chance of making the joint. Fig. 160-a. Keep pouring and with the left hand hold the cloth C to catch the solder and also cause the same to tin the lower side of the pipe and to keep the solder from dropping down. This cloth, so important in joint making is elsewhere described. By the process of steady pouring the solder now becomes nice and soft and begins to feel shaped, firm and bulky. When in this shape and in a semi-fluid condition quickly put the ladle down, and instantly with the left hand shape one side of the joint always beginning at the outsides, or at that part Maxims and Instructions, 303 LEAD PIPE JOINTS, next the soiling; then take the cloth in the right hand and do the other side, finisliing on the top; a light run of the cloth all round the joint will, if the solder has not set and you have been quick with your work, give the appearance of a turned joint. After a little practice the joint may be made without changing the cloth from one hand to the other. The secret of joint making is getting the lead to the heat of the solder and in roughly shaping the solder, while in the semi- ■fluid state. Good mechanical fitting is the result of two things — good judgment and a delicate sense of touch. REPAiRii^G Pipes with Putty Joints. First get the pipe thoroughly dried, and with some quick drying gold size paint the part to be repaired; then get some white lead and stiffen it with some powdered red lead, so as to make it a hardish putty, place a thin layer of this, say f th inch to ^ inch in thickness, over the bursted part of the pipe, and with some good strong calico, painted with the gold size, neatly wrap the red lead to the pipe, using 3 or 4 thick- nesses of the painted calico; then with some twine begin at one end, laying the twine in several layers in rotation until it has, like the calico, several thicknesses. If properly done this will be strong enough to withstand any ordinary press- ure on the pipes and if more is required the putty can be made from dry red lead and gold size. In making all white and red lead joints, first, see that the parts are thoroughly dry; second, see that the parts are not dirty with rust, &c.; next, well Fig. 161. paint the parts with good, stiff paint be^ tore putting the putty on to form the joint. J04 Maxims and Instructions, BENDING LEAD PIPE. If any ordinary piece of light lead pipe \\ inches in diame- ter is taken and pulled or bent sharply around it will crimple or crinkle at the throat; the larger and thinner the pipe the more it will become distorted. There are many methods of making these bends in lead pipe, some with dummies, others with bolts, balls, etc., others cut the bends at the back, at the throat or the two sides of the bend. For small j)ipes, such as i to 1 inch and extra heavy, they may be pulled round without trouble or danger, but for a little larger size sakd bei^^ding is largely practiced, as follows : Take the length of pipe, say 5 feet, fill and well ram it with sand 2 feet up, then have ready a metal pot of very hot sand to fill the pipe 1 foot up, next fill the pipe up with more cold sand, ramming it as firmly as possible, stop the end and pull round the pipe, at the same time hammering quickly working the lead from the throat towards the back, which can be done if properly worked. N. B. — Care must be used not to reduce or enlarge the size of the bore at the bend. Bekding with Watee. — It is a well-known fact that for such work, water is incompressible, but may be turned of twisted about for any shape provided it is enclosed in a soKd case. To make the bend — the end of the pipe is stopped and a stop cock soldered into the other end; take the pipe at the end and pull it around, being careful that the water does not cool and shrink, and hammering quickly to take out the crinkle. Bexding with Balls. — This method is practiced with small pipe and also to take '^ dints '' out in case of sand and wat»^r bending when a ball is sent through. Method: suppose the pipe to be 2 inches, then a ball is required iV in. less than the pipe, so that it will run through the pipe freely. Now pull the pipe round until it just begins to flatten, put the ball inio the pipe and with some short pieces of wood, say 2 in. long by 1^ in. in diam., force the ball through the dented part of the pipe. The ball will run through all the easier if '^'touched" over with a candle end. Care must be used in forcing the ball ^ack and forth not to drive it through the bend. Maxims and Instructions. 305 Table. — ^Weight of Sheet Lead. c? c^ -r-\ • • Oi t- «o 4 • • 00 on r^ ^ • a • • ci ^ 1 10 4 • • ^ 1 * 00 ^ 00 • 00 ^ ^ 4 oi CO 0^ 00 ,> TH -!— ( • 1 1 1 1 CD •rt< CO CO Oi 0^ C5 CO ^ 00 1 - 4 4 ci ^ <^ 1 T— 1 a o> T*< CO ^ ^ ' 4 tH tH D^ ci Ci 1—1 •I— 1 4 00 00 00 CQ :i I 1 CO C^ C* r- ;^ = . 1 tH 0. 1 ^\ 1 \ ^^ \ ^• « „ ^ « « i- ^ ^ '^ " " ^ "• a a P . et % c ^ ^ «• » « ^ ,. a »- 1 - ^ »» 3 « >• <1 1 <{ <1 <1 m Q ft w Sheet lead is not the same weight, bulk for bulk, ow- ing to difference in organic formation, but a cubic foot may be said to weigh 709 lbs. A square foot 1" thick, 59 '' (( C( .. ^, << ^ '^ i< ii (C 6 " a a (C 5 '' a a a 4 '' a (( '' i/ a 3 '' Sheet lead is sometimes made as paper. thin as writing Plumber's Solder. Rule for making. — Take loo lbs. good old lead or lead cuttings, run it down thor- oughly, stir it up and take off all dirt or dross: then take 50 lbs. pure tin, let this run down, and when nearly all is melted and is a little cooler throw in 1^ lb. of black rosin, and well stir the lot up. Last bring up the heat to 600 degrees which may be known by the burning of a bit of newspaper put in the pot. The solder is now hot enough and should be well stirred and then run into moulds. jo6 Maxims and Instructions. PLUMBEK^S TOOLS Fig. 163. Fig. 162. The processes of lead working are executed by manual dexterity acquired by long prac- tice, and to do the work properly require s many special tools. Some of these are used in common with other departments of mechanics but are none the less neces- sary in lead working. We present cuts of the principle tools used some of which are self explaining and some are named with further de- secription of particular use. 3 Fig. 162 represents one form of the plumber's tap borer or Fig. 165. reamer, used for making and en- larging holes in pipe. Fig. 163 represents plumber's snips. Fig. 164 is the well-known and always useful ladle. Fig. 165 is the round nose pcne hammer, used in plumber's work to open the inside pipe before jointing. Fig. 166 is the plumb bob. The same cut will also convey an idea of the wooden instru- ment used to force open the pipe before joint- Fig. 166. ing, i. e., "the turn pin.'' Fig. 164. Maxims and Instrttctions. 307 PLUMBER'S TOOLS. ! g"- ' Mr I Fig. 167. Fig. 168. Fig. 169. Fig. 170. ■■ Fig . 171. Fig. 167 represents '' the round nose chisel.^' Fig. 168 is the ^''wood chisel"" nsed in cutting away wood, work. Fig. 169 is the half round nose chisel. Fig. l^Oisthewell- Kinown ^*^cape chisel.-'' Fig. 171 is the equally well-known '' cold chisel." Fig. 172 is the diamond nose chis- Fig. 172. 3 173. Fig. 174. Fig. 173 shows a rivet set for small work connected with ^^^ plumbing and sheet metal work. Fig. 174 exhibits the plumber's torch this is also used by engineers to explore interiors of boilers, chimney flues, and other dark places about the steam plant. Fig. 175 is a compass saw. Fig. 176 is a double edged plumber's saw. Fig. 177 is a spirit level. Fig. 178 is a looking-glass used in making underhand joints and in many- useful ways about a steam plant. 3o8 Maxims and Instructions. PLUMBER'S TOOLS. Fi2r. 178. Fig. 179. Fig. 180. Fig. 183. Fig. 181 is a soldering tool known ^ among plumbers as '^'a copper point- ed bolt." rig. 182 is a copper-poin- ted bolt, flat. Fig. 183 represents a hanger, for s u s p e n d i ng iron and lead Fig. 181. Fig. 183. pipe; its ex- cellence con- sists in enab- ling pipes to be raised or lowered arter being hung without taking the hanger apart. Maxims and Instructions. 309 USEFUL TABLES OF WEIGHTS OF IRON AND COMPARISONS OF GAUGES. Weight of a Superficial Foot of Plate and Sheet Iron Plate Iron. Sheet Iron. Weight per -^d United States Standard Guage. Thick- opted by Congress, to take effect July 1st, 1893. 116SS. square foot. N UMBER OF lOOO^s Of Weight per square foot. OUNCES Nearest fraction of INCHES. POUNDS. C JUAGE. an inch. an inch. V16 iD. 2^ N 0. 1 .281 180 oz. 9/32 in. % - 5 ' 2 .205 170 " "/64 • 3/16 «• 71^ ' 3 .250 160 " Va ' ^ - 10 ' 4 .234 150 " 15/64 ' 5/16 " 12K ' 5 .218 140 " 1/32 ' % •• 15 ' 6 .203 130 " 13/64 . '/16 •• 17^ ' 7 .187 120 " 3/16- . % ' 20 • 8 .171 110 ' 11/64 ' »/l6 " 22^ ' 9 .156 100 " 5/32 . ^e" 25 ' 10 .140 90 " % ' 27^ • 11 .125 80 " Vs • 30 ' 12 .109 70 " ^/64 ' 321^ ' 13 .093 60 " 2/32 ♦ ;g •' 35 ' 14 .078 50 " 5/64 ♦ 15/16 " 3 73^^ ' 15 .070 45 • ^/l28 ' 1 ♦' 40 ' IG .062 40 " I/16 ' ' 17 .056 36 " ^/l60 ' ' 18 .050 32 ♦ 1/20 ' ' 19 .043 28 »' Vm ' ' 20 037 24 • 3/80 ' ' 21 034 22 " 11/320 ' ' 22 .031 20 ' 1/32 • ' 23 .028 18 " ^/320 ' ' 24 .025 16 ' 1/40 ' ' 25 .021 14 " ^/320 ' ' 26 .018 12 ' 3/16O « • 27 017 11 " 11/640 ' ' 28 .015 10 '• 1/64 ' ' 29 014 9 ': «/6^0 • ' 30 .012 8 '• 1/80 • 310 Maxims and Instructions. USEFUL TABLES. Weight of One Foot of Bound Iron • Size, Weight pr. Foot.' Size. Weight pr. Foot. Size. Weight pr. Foot. LBS. Lbs. Lbs. y^m. .041 ItV in. 5.41 3K in. 32.07 yV - .092 IK •• 5.89 Ws .. 34.40 k .. .164 t :: 6.39 3^ ... 36.82 ■i^ .. .256 6.91 SVs .. 39.31 % .. .368 Hi .. 7.45 4 .. 41.89 tV .. .501 \% .. 8.02 4^ .. 44.55 .654 8.60 4^ .. 47.29 y9g. . . .828 \y^ , . 9.20 4% .. 50 11 %'•'• 1.02 HI •• 9.83 4K .. 53 01 1.24 % ., 10.47 4,5^ .. 66.00 1.47 ^Vs .. 11.82 i% .. 59.07 i:. 1.73 2H .. 13.25 4;g .. 62.22 2. 00 2% .. 14.77 5 ., 65.45 \% .. 2.30 2V2 .. 16.36 ^Vs .. 68.76 1 .. 2.62 2f| .. 18.04 5J^ .. 72.16 liV .. 2.95 2M .' 19.80 5M .. 75.64 Wz .. 3.31 2/8 •• 21.64 5K .. 79.19 rh .. 3.69 3 .. 23.56 5.^^ .. 82.83 IK .. 4.09 dVs .. 25.57 5% .. 86.56 4.51 3^ .. 27.65 5^ .. 90.36 1% •• 4.95 3^ .. 29.82 6 .. 94.25 Weight of One Foot of Square Iron Size. Weight pr. Foot Size. Weight pr. Foot. Size. Weight pr. Foot Lbs. Lbs. Lbs. Vs in. .052 h\ in. 6.89 3K in. 40.83 i .. .117 ik .. 7.50 3^ .. 43.80 M .. .208 h\ .. 8.14 3^ .. 46.88 .326 IM .. 8.80 m " 50.05 .469 hI .. 9.49 4 .. 63.33 tV • • .638 i5 .. 10 21 41^ .. 66.72 }4 •• .833 iH«. 10.95 4^ .. 60.21 •^ir . .- 1.06 i;^ .. 11.72 ^Vs .. 63.80 % • • 1.30 HI .. 12.51 4K .• 67.50 H • • 1.58 2 .. 13.33 ^rs .. 71.30 X .. 1.87 21^ .. 15.05 43/^ .. 75.21 ^f . 2.20 2^ .. 16.88 4% .. 79.22 rs •• 2.55 2% .. 18.80 ' 5 .. 83.33 (1 . 2.93 2i| .. 20.83 51^ .. 87.55 1 .. 3.33 25^ .. 22.97 5^1 .. 91.88 v^ .. 3.76 2^ .. 25.21 5M •• 96.30 ni .. 4.22 2^ .. 27.55 5K .. 100.80 h\ . . 4.70 3 ■ .. 30.00 5.4 .. 105.50 1^1 .. 5.21 31^ .. 32.55 5^1 .. 110.20 h\ •• 5.74 314.. 35.21 d .. 115.10 1% .. 6.30 3% .. 37.97 6 .. 120.00 Maxims and Instructions, 311 USEFUL TABLES. Weight per Running- Foot of Cast Steel. Size. Lbs. Size. Lbs. 1 Size. Lbs Size. Lbs. y^ in. S(i. .213^ M in, Rd. .167 1 x^ .852 M in. Oct. .745 K • • • • .855 K .. .• .669 13^>^M 1.43 5/ 1.16 ^ . . . . 1.91 % •• .. 1.50 \\^'^V. 2 13 M*.. .. 1 67 1 .. .. 3.40 I .. .. 2.67 l^x^ 3.19 %, .. .. 2.28 \M .. .. 5.32 V4. .. .. 4 18 1^4x^4 4 46 1 .. .. 2.98 \% .. .. 7.67 Wi .. .. 6.02 2 xi^ 3 40 Wz •• .- 3.77 a .. .. 13.63 3 .. 10.71 [.. x% 4 25 1^.. . 4 65 Comparison of Principal Ouages in use United States Standard. Stubbs' Birmingham. Brown & Sharp. Niira- ber. lOOO's of an inch. Pounds per square foot. IRON. lOOO^s of an inch. Pounds per square foot. iron. lOOO's of an inch. Pounds per square foot. iron. No. 1 .281 11.25 .300 12 04 .289 11.61 - 2 .265 10.62 .284 11.40 .257 10.34 '* 3 .250 10. .2.59 10.39 .229 9.21 - 4 .234 9.37 .2.38 9.55 .204 8.20 •• 6 .218 8.75 .220 8.83 .181 7.30 " 6 .203 8.12 .203 8.15 .162 6.50 " 7 .187 7.50 .180 7 22 .144 5.79 •' 8 .171 6.87 165 6 62 .128 5.16 " 9 .156 6.25 .148 5.94 .114 4 59 **10 .140 5.62 .134 5. 38 .102 4.09 *'ll .125 5.00 .120 4.82 .091 3.64 "12 .109 4.37 .109 4.37 .080 3 24 " 13 .093 3 75 .095 3.81 .072 2.89 - 14 .078 3.12 .083 3 33 .064 2.57 "15 .070 2.81 .072 2.89 .057 2.29 **16 .062 2.50 .065 2.61 .050 2 04 "17 .0.56 2.25 .058 2.83 .045 1.82 "18 .050 2.00 .049 1.97 .040 1.62 " 19 .043 1.75 .042 1 69 .036 1 44 r 20 .037 1.50 .035 1 40 .032 1.28 f'21 .034 1.37 .032 1.28 .028 1.14 1" 22 .031 1.25 .028 1.12 .025 1.02 "23 .028 1.12 .025 1.00 .022 .90 "24 .025 1.00 .022 .88 .020 .80 "25 .021 .87 .020 .80 .018 .72 "26 .018 .75 .018 .72 .016 .64 "27 .017 .68 .016 .64 .014 .57 "28 .015 62 .014 .56 .012 .50 "29 .014 .56 .013 ..52 .011 .45 " 30 .012 .50 .012 .48 .010 .40 312 Maxims and Instructions. NOISELESS WATER HEATER. This device is very effective for heating water in open or closed tanks by direct steam pressure without noise. The heater consists of an outward and upward discharging steam nozzle, covered by a shield "which has numerous openings for the admission of water so that the discharge jet takes the form of an inverted cone, discharging upwards. ■STEAM Fig. 184. A small pipe admits air to the steam jet, and by mixing therewith prevents a collapse of the steam bubbles, and the noise, which is such a great objection to heating by direct steam in the old way. A valve or cock on the small air pipe regulates the opening as may appear most desirable. Exhaust steam can by the same method be disposed of under water without noise. Maxims and Instructions, jij ACCIDENTS Al^D EMERGENCIES. Few subjects can more usefully employ the attention and study of engineers than the proper treatment and first remedies made necessary by the peculiar and dis- tressing accidents to which persons are liable who are employed in or around a steam plant. These and many other things of a like nature are likely to call for a cool head, a steady hand and some practical knowledge Fig. 184 of what is to be done. In the first moments of sudden disaster, of any kind, the thoroughly trained engineer is nearly always found, in the con- fusion incident to such a time, to be the one most competent to advise and direct the efforts made to avert the danger to life limb or property, and to remedy the worst after effects. To fulfil this responsibility is worth much previous prepara- tion, so that the best things under the circumstances may be done quickly and efficiently. To this end the following advice is given relating to the most common accidents which are likely to happen, in spite of the utmost exercise of care and prudence. 13urns and Scalds, — Burns are produced by heated solids or by flames of some combustible substance; scalds are produced by steam or a heated liquid. The severity of the accident depends mainly, 1, on the intensity of the heat of the burning body, together with, 2, the extent of surface, and, 3, the vitality of the parts involved in the injury, thus: a person may have a finger burned off with less danger to life than an extensive scald of his back. The immediate effect of scalds is generally less violent than that of burns; fluids not being capable of acquiring so high a temperature as some solids, but flowing about with great facil- ity their effects become most serious by extending to a large surface of the body. A burn which instantly destroys the part ^t/f. Maxims and InstrMctions. ACCIDENTS AND EMERGENCIES, which it touches may be free from dangerous complications, if the injured part is confined within a small compass; this is owing to the peculiar formation of the skin. The skin is made up of two layers; the outer one has neither blood vessels nor neryes, and is called the scarf-skin or cuticle; the lower layer is called the true skin, or cutis. The latter is richly supplied with nerves and blood vessels, and is so highly sensitive we could not endure life unless protected by the cuticle. The skin, while soft and thin, is yet strong enough to enable us to come in contact with objects without pain or inconvenience. The extent of the surface involved, the depth of the injury, the vitality and sensibility of the parts affected must all be duly weighed in estimating the severity and danger of an accident in any given case. In severe cases of burns or scalds the clothes should be removed wiih the. greatest care — they should be carefully cut, afc the seams, and not pulled off. In scalding by boiling water or steam, -cold water should be plentifully poured over the person and clothes, and the patient then be carried to a warm room, laid on the floor or a table but not put to bed, as there it becomes difficult to attend further to the injuries. The secret of the treatment is to avoid chafing, and to heep out the air. Save the skin unbroken, if possible, taking care not to break the blisters; after removal of the clothing an application, to the injured surface, of a mixture of soot and lardy is, according to practical experience, an excellent and efficient remedy. The two or three following methods of treat- ment also are recommended according to convenience in obtaining the remedies. Take ice well crushed or scraped, as dry as possible, then mix it with fresh lard until a broken paste is formed; the mass should be put in a thin cambric bag, laid upon the burn or scald and replaced as required. So long as the ice and lard are melting there is no pain from the burn, return of pain calls for a repetition of the remedy. Maxims and Instructions, j/5 BURNS AND HEAT STROKES. The free use of soft soap upon a fresh burn will remove the fire from the flesh in a very little time, in J to -J an hour. If the burn be severe, after relief from the hum, use linseed oil and then sift upon it wheat flour. When this is dried repeat the oil and flour until a complete covering is formed. Let this dry until it falls off, and a new skin will be formed without a scar. In burns with lime, soap lye, or any cavstic alkali, wash abundantly with water (do not rub), aud then with weak vine- gar or water containing a little sulphuric acid; finally apply oil, paste or mixture as in ordinary bilrns. It would be well to always keep ready mixed an ointment for burns; in fact a previous readiness for an accident robs it of half its ill effects. Glue Buen Mixture. A method in use in the N". Y. City Hospital known as the '•■glue burn mixture "" is composed as follows: '^1^ Troy oz. white glue, 16 fluid oz. water, 1 fluid oz. glycerine, 2 fluid drachms carbolic acid. Soak the glue in the water until it is soft, then heat on a water bath until melted; add the glycerine and carbolic acid and continue heating until, in the intervals of stirring, a glossy strong skin begins to form over the surface. Pour the mass into small Jars, cover with parafine papers and tin foil before the lid of the jar is put on and afterwards pro- tect by paper pasted round the edge of the lid. In this manner the mixture may be preserved indefinitely. When wanted for use, heat in a water bath and apply with a flat brush over the burned part/' Insensibility from Smoke, — To recover a person from this dash cold water in the face, or cold and hot water alternately. Should this fail turn the patient on his face with the arms folded under his forehead; apply pressure along the back and ribs and turn the body gradually on the side; then again slowly on the face, repeating the pressure on the back: continue the alternate rolling movements about sixteen times a minute until breathing is restored. A warm bath will com- plete the cure. Ji6 Maxims and Instructions. -. _ . . — rfi TREATMENT OF CUTS AND WOUNDS. Heat-sir ohe or Siin-strohe, — The worst cases occur where the sun^s rays never penetrate and are caused by the extreme heat of close and confined rooms, overheated work- shops, boiler rooms, etc. The symptoms are, 1, a sudden loss of consciousness; 2, heavy breathing; 3, great heat of the skin; and 4, a marked absence of sweat. Treatment. — The main thing is to lower the temperature. To do this, strip off the clothing, apply chopped ice wrapped in flannel to the head; rub ice over the chest, and place pieces under the armpits and at the side. If no ice can be had use sheets or cloths wet with cold water, or the body can be stripped and sprinkled with cold water from a common watering pot. Cuts and Wounds, — In tliese the chief points to be attended to are: 1, arrest the bleeding; 2, remove from the wound all foreign bodies as soon as possible; 3, bring the wounded parts opposite to each other and keep them so; this is best done by means of strips of adhesive plaster, first applied to one side of the wound and then secured to the other; these strips should not be too broad, and space must be left between the strips to allow any matter to escape. Wounds too exten- sive to be held together by plaster must be stitched by a sur- geon, who should always be sent for in all severe cases. For washing a wound, to every pint of water add 2J tea- spoonfuls of carbolic acid and 2 tablespoonfals of glycerine — if these are not obtainable, add 4 tablespoonsful of borax to the pint of water — wash the wound, close it, and apply a com- press of a folded square of cotton or linen; wet it in the solnticn used for washing the wound and bandage down quickly and firmly. If the bleeding is profuse, a sponge dipped in very hot water and wrung out in a cloth should be applied as quickly as possible — if this is not to be had, use ice or cloth wrung out in ice water. Wounds heal in two ways. 1, rapidly by primary union, without suppuration, and leaving only a very fine scar. 2, slowly by suppuration and the formation of granulations and leaving a large red scar. Maxims and Instructions, jiy ACCIDENTS AND EMERGENCIES. bleeding, — This is of three kinds: 1, from the arteries which lead from the heart; 2, that which conies from the veins, which take the blood back to the heart; 3, that from the small veins which carry the blood to the surface of the body. In the first, the blood is bright scarlet and escapes as though it was being pumped. In the second, the blood is dark red and flows away in an uninterrupted stream. In the third, the blood oozes out. In some wounds all three kinds of bleeding occur at the same time. The simplest and best remedy to stop the bleeding is to apply direct pressure on the external wound by the fingers. Should the wound be long and gaping, a compress of some soft material large enough to fill the cavity may be pressed into it; but this should always be avoided, if possible, as it prevents the natural closing of the wound. Pressure with the hands will not suffice to restrain bleeding in severe cases for a great length of time and recourse must be had to a ligature; this can best be made with a pocket hand- kerchief or other article of apjoarel, long enough and strong enough to bind the limb. Fold the article neck-tie fashion, then place a smooth stone, or anything serving for a firm pad, on the artery, tie the handkerchief loosely, insert any available stick in the loop and proceed to twist it, as if wringing a towel, until just tight enough to stop the flow. Examine the wound from time to time, lessen the compression if it becomes very cold or purple, or tighten up the handkerchief if it commences bleeding. Some knowledge of anatomy is necessary to guide the opera- tor where to press. Bleeding from the head and upper neck requires pressure to be placed on the large artery which passes up beside the windpipe and just above the collar bone. The artery supplying the arm and hand runs down the inside of the upper arm, almost in line with the coat seam, and should be pressed as shown in Fig. 184. The artery feeding the leg and foot can be felt in the crease of the groin, just where the flesh of the thigh seems to meet the flesh of the abdomen and this is the best place to apply the ligature. In arterial bleeding the ji8 Maxims and Instructions. ACCIDENTS AND EMEEGENCIES. pressure must be put between the heart and the wound, while in venous bleeding it must be beyond the wound to stop the flow as it goes towards the heart. ' In any case of bleeding, the person may become weak and faint; unless the blood is flowing actively this is not a serious sign, and the quiet condition of the faint often assists nature in staying the bleeding, by allowing the blood to clot and so block up any wound in a blood vessel. Unless the faint is prolonged or the patient is losing mxuch blood, it is better not to hasten to relieve the faint condition; when in this state any- thing like excitement should be avoided, external warmth should be applied, the person covered with blankets, and bot- tles of hot water or hot bricks applied to the feet and arm-pits. Frost-hite, — No warm air, warm water, or fire should be allowed near the frozen parts uutil the natural temperature is nearly restored; rub the affected parts gently with, snow or snow water in a cold room; the circulation should be restored very slowly; and great care must be taken in the after treat- ment. l^vohen Sones, — The treatment consists of, 1, carefully removing or cutting away, if more convenient, any of the clothes which, are compressing or hurting the injured parts; 2, very gently replacing the bones in their natural position and shape, as nearly as possible, and putting the part in a position which gives most ease to the patient; 3, applying some tempo- rary splint or appliance, which will keep the broken bones from moving about and tearing the flesh; for this purpose, pieces of wood, pasteboard, straw, or firmly folded cloth may be used, taking care to pad the splints with some soft material and not to apply them too tightly, while the splints may be tied by loops of rope, string, or strips of cloth; 4, conveying the patient home or to a hospital. To get at a broken limb, or rib, the clothing must be removed, and it is essential that this be done without injury to the patient; the simplest plan is to rip up the seams of such garments as are in the way. Boots must be cut off. It is not imperatively necessary to do anything to a broken limb before the arrival of a doctor except to keep it perfectly at rest. Maxims and Insiructions, jig ACCIDENTS AND EMERGENCIES. Poultices, — These outward applications are useful to relieve sudden cramps and pains due to severe injuries^ sprains and colds. Tlie s.cret of applying a mustard is to apply it hot and keep it so by frequent changes — if ifc gets cold and clammy it will do more harm than good. Poultices to be of any service and hold its heat should be from one-half to one inch thick. To make it, take flaxseed, oatmeal, rye meal, bread, or ground slippery elm; stir the meal slowly into a bowl of boiling water, until a thin and smooth dough is formed. To apply it, take a piece of old linen of the right size, fold it in the middle; spread the dough evenly on one half of the cloth and cover it with the other. To make a '' mustard paste ^^ as it is called, mix one or two tablespoonfuls of mustard and the same of fine flour, with enough water to make the mixture an even paste; spread it neatly with a table knife on a piece of old linen, or even cotton cloth. Cover the face of the paste with a piece of thin muslin. Sow to Carry an Injured Person, — In case of an injury where walking is impossible, and lying down is not absolutely necessary, the injured person may be seated in a chair, and carried; or he may sit upon a board, the ends of v/hich are carried by two men, around whose necks he should place his arms so as to steady himself. Where an injured person can walk he will get much help by putting his arms over the shoulders and round the necks of two others. A seat may be made with four hands and the person may be thus carried and steadied by clasping his arms around the necks of his bearers. If only one person is available and the patient can stand up, let him place one arm round the neck of the bearer, bringing his hand on and in front of the opposite shoulder of the bearer. The bearer then places his arm behind the back of the patient and grasps his opposite hip, at the same time catching firmly hold of the hand of the patient resting on his shoulder, wdth his other hand; then by putting his hip behind the near hip of the patient, much support is given, and if necessary, the bearer can lift him oif the ground and as it were, carry him along. ^20 Maxims and Instructions, ACCIDENTS AND EMERGENCIES. To carry an injured person by a stretcher (which can be made of a door, shutter, or settee— with blankets or shawls or coats for pillows) three persons are necessary. In lifting the patient on the stretcher it should he laid with its foot to his head, so that both are in the same straight line; then one or two persons should stand on each side of him, and raise him from the ground, slip him on the stretcher; this to avoid the necessity of any one stepping over the stretcher, and the liabil- ity of stumbling. If a limb is crushed or broken, it may be laid upon a pillow with bandages tied around the whole (i. e,, pillow and limb) to keep it from slipping about. In carrying the stretcher the bearers should '' break step " with short paces; hurrying and jolting should be avoided and the stretcher should be carried so that the patient may be in plain sight of the bearers. PEESONAL. The fireman, so called, in steam service of any description, should and does on the average receive double the compensation of a man loho has only his lalor to bargain for. In addition, he exercises his slcillful vocation in sheltered places and is almost the last of the employees of a plant to he " laid off*^ and is certainly the first to he called on again after stoppage. Still further, the fireman has an almost equal opportunity, with the hest shop trained machinist, for advancement to the position of engineer in charge of the most extensive steam plants. Now I this increased pay over ordinary labor and other numerous advantages accruing from the position, demand a generous return, and in ending this work, the author suggests these ^'points " for observance to the aspiring student, whether engineer, fireman, or machinist, namely— that sobriety should he held one of the first elements of strict observance; an unrest- ing tidiness of person and premises; dignity of conduct, as being oived to the rising profession of steam, engineering; and lastly, an unswerving fidelity of trust, tvhich may include hon- ^jit"/. iruthfuhifiss and couraae. INDEX. A.rclclents and Emergencies, 313. Factory rules to prevent, 293. Government rules to prevent, 290. Acid, definition, 137. Advantages of triple draught tubular boiler, 84. Air used in burning 1 lb. of coal, 14. ditto, bow supplied to the coal, 14. Description, 16. As a material substance, 16. Density at different depths, 16. Weight of a column of air, 17. As a fluid, 17. As an impenetrable body, 17. Five "points'* for the engineer, 17. Composition of, 17. Specific heat of, 215. Air valve, use of, 255. Alcoliol, specific heat of, 214. Alkalies, definition, 137. Alum, boiling point of, 37. Ammoniac (Sal), boiling point of, 37. Analysis of antracite coal, 13. Of bituminous coal, 13. Of wood, 13. Of heat, 13. Of scale deposited in marine boil- ers, 146. Of feed waters, 139-140. Angle and T iron, dimensions and shape, 104. Angle brick, 237. Angle-valve, description, 273. AntUracite coal, analysis of. 13. Ignited with difficulty, 16. Antimony, melting point, 42, Answers of applicants for a marine license, 127. Arcli-brici«,237. Area of safety valve, rule for find- ing, 192. Asli pit, the, 238. How kept during firing, 27. Assistant engineers, classification of, 310. Back pressure valves, description, 273. Baffle plate, descriptioo, 169, ^80. Ball valve, description, 273. Bark, effect on steam boilers, 151. Barrel, rule for finding contents of 203. Bars, grate, description, 173. Before lighting tlie fire, direc- tions, 25. Belts, how to safely run on pullies, 291. Bending lead pipe, 304. Bib cocii, description, 273. Bituminous coal, analysis of, 13. How burned, 16. Blast pipe for marine boiler, 63. Bleeding, treatment of, 317. Blow^ers for shavings, 20. Blow off, description, 81. Surface, description, 161. Boilers, description, 48. Upright steam, 50. Crude form, 52. Plain cylinder, description, 52. Cornish, description, 54. Lancashire, description, 55. Galloway, description of, 58. Marine, description of, 60, Marine, table of dimensions, 62. Locomotive portable, 80. Construction of, 89. Caulking, 94. Dangers from syphoning, 288. Dangers from gas, 288. Foaming in, 43. Fulcring, 94. Horse power of, 234. Proper steam connection for, 276. Boiler braces, "points" relating to. 104. Boiler coverings, 273. Boiler, Compound, composition of, 151-152. Compound, for locomotives, 149. Boiler castings, specifi'^ation of, 86. Boiler cleaners, mechanical descrip tion, 159, 16. Boiler explosions, causes of, 28S Boiler fittings and mountingr g'?. Fixtures, description, 164. Poller flue brusltes, use of, 21. 322 Index. Doiler fronts, description, 165. Boiler Injector, description, 206. Boiling, process of, 37. Boilin<^ points of various substan- ces, 37. Boiler maker's tools and machin- ery, 281. Boilers newly set, liow fired, 28. No two alike, 25. Boiler and pipe covering, mix- tures for, 275-276. Boiler plates, example of riveting, 114. Marks on, 88. Boiler repairs, 123. Note, 125. Boiler scale, analysis of, 148. Boiler scum, how formed, 150. Boiler setting, 236. Boiler steel, description of quality, 90. Boiler tubes, dimensions of lap weld- ed tubes, 110. Table of holding power. 111, Experiments in strength of, 111. Notes, 110, 112. Illustration of size, 245. Boiler testing, specification, 87. Bolts, strain on, rule, 99. Socket, description, 103. Bolt, plumber's copper pointed, 308. Bones, broken, treatment of, 318. Borer, tap, plumber's, 308. Box coil, description, 257. Brace, difference between, and stay, 103. Head to head, description, 103. Crow foot, 103. Braces, shop names for, 103. Table for calculations, 107-109. T; 3 of diameters, 103. Inspector's rules, 102. Specification for, 86. " Points " relating to, 104. Bracing of steam boilers, 96. Bracket, valve, description, 273. Brass, conducting power of, 213. Brick, furnace, 237. Brine valve, description, 277. Broken bones, treatment of, 318. Burns and scalds, treatment of, 313. Burn mixture, 315. Busliing, description, 274. Butt joint, illustration. Calculations relating to stearn. heat- ing, 263. Relating to pumps, 23. Relating to safety valves, 191. C^aUpersi use of, 2^. Cape chisel, 307, 281. Carbon, description of, 229. Carbonate, definition, 136. Of magnesia, definition, 138. Of lime, at what temperature depos- ited, 148. Carbonic acid, in water how dectec- ted, 153-154. Specific heat of, 215. Carbonic acid gas, description of, 230. Carbonic oxide, description of, 231. Specific heat of, 215. Carbonizatian, method of, 15. Care and management of the steam boiler, 24, Care of steam fittings, 268. Care of Avater tube boilers, 70. Castings, for boiler, specification, 86. Caulking, descriplion, 94. Caulking tools, plumber's, 308. Certificates of Inspection, issuing of, 131. Cliain riveting, example, 93. Chapter of " Don'ts," 44-47. Charcoal, description, 15. Specific heat c: . 314. Charcoal Iron, description, 88. Check valve, description, 273. Chemical terms relating to feed water, 136. Chemistry, definition, 136. Chemistry of the furnace, 226. Chief engineers, classification of, 310. Chimney draught, 296. Chisel, cold, 307. Cape, 307. Round nose, 307. Half round nose, 307. Wood, 307. Diamond nose, 307. Gasket, 308. Chloride, definition, 137. Chlorides, how indicated in water, 157. C. H. No. 1 F, 88. C. H. No. 1 FB, 88. Circle brick, 237. Circulation, water, 294. Cisterns, capacity of, 202. Clamp, boiler, description and cut, 123. Classification of marine engi- neers, 310. Cleaners, mechanical boiler, descrip- I tion, 159-160. (Cleaning out boilers under firing,0i. CqiiI t^r, 4ow best fired* 3Q. Index. ^ A A CoaU 13. What it consists of, 13. Common proportions, 13. Introduction of air in burning, 13. Bituminous, how it burns, 16. Anthracite, how it burns, 16. Comparative evaporation, 18. Specific heat of, 214. Storing and handling of, 225. Cocks, description, 270. Valve, description, 273. Gauge, description, 170. Bib, description, 273. Three way, description, 273. Four way, description, 273. Coil) box, description, 257. ripe, description, 257. Coke, description, 15. Comparative evaporation, 18. Ratio between heating and grate surface, 28. How best fired, 28. Specific heat of, 314. Cold cliisel, 307. Cold sliortj definition, 121. Columns, glass water gauge, 177. Combustible parts of coal, 16. Combustion, operation on materials, 16. Chamber, 238. Chambers of marine boilers, 63. Compasses, use of, 23. Compass saw, 308. Compound, boiler, composition, 151-2. For locomotive boilers, 149. CNo. 1, iron, 88, Condenser, surface description, 65. Operation of, 66. Conducting powder of various sub- stances, 213. Conical head of rivets, description, 113. Construction of boilers, description, 89. And drawing rivet heads, 113. Contraction of area, definition, 121. Conveyors, screw, 20. Copper, conducting power of, 213. Radiating power of, 213. Specific heat of, 214. Cornish boiler, description of, 54. Defects of, 54. Corrosion of steam boilers, 126, 143, 144. Coverings for pipes and boilers, 375. Coupling, description, 374. For pipe, 250. Cracks in boilers, how to repair, 133. Cross T, description, 374. Crowfoot brace, 103. Cup head of rivets, description, 113 Cutaway front, description, 10.5-167. Cuts and Avounds, treatment of, 316. Cylinder boiler, description, 52. Defects of, 53. Dampers and doors to the furnace, 39. Oamper regulators, description, 185. Danger, points, in steam boiler, 135. Dart, description and cut, 19. Dead end of pipe, 284. Dead plate, description, 180, 337. Dead steam, description, 383. Dedication, 5. Defects, table of, 125. Defects and necessary repairs to boil- ers, 123. Definition of Terms, 131. Designing boilers, relating to stayed surfaces, 99. Device for using kerosene oil, 158. Diamond nose chisel, 307. Directions before lighting the fire, 25 For firing with various fuels, 27. Disc for boiler makers, 281. "•Don'ts," a chapter of, 44-47. Doors, furnace, description, 168-170. Double beat valve, description, 373. Also see Fig. 158. Double seat valve, description, 373. Drain, the steam, description, 81. Drainage and piping, description and illustration, 399. Drain cock, description, 181. Draughts, at time of lighting the fire, 36. Of chimney, 396. Regulating the draught, 41. Drawings of rivet heads, 113. Drum, mud, description, 179. Dry steam, description, 383. Ductile, definition, 121. Dudgeon expanders, description, 281. Duties of the flreman, 27. Duty of boiler, specification, 87. Dust (coal), firing of, 40. Economizer, fuel, description, 185w Elasticity, definition, 121. Elastic limit, definition, 121, Elbow, description, 274. Element, definition, 136. Ell, description, 274. Elongation of steel plate, 90i Definition, 121. Ether, specific heat of, 314. 324 Index. Eni^ineer's questions, 133. Examinations, "points," 133-133. Tests for impurities in water, 153. Evans, Robt., 11. £xanilnatioii of engineers, 133. Exbaiist steam heating, 267. Expanders (dudgeon), 281, Expansion (linear), of steam pipe, 270. Explosions, boiler, 286. Of steam pipe, 287. Factory rules to prevent accident, 293. Fatigued, definition, 121. Feed water, analysis of, 139-140. Engineer's tests, 153. A precipitator for sea water, 146. Examples of analysis, 140-141. Preliminary precipitation, 144. Description, 196. Heaters, "• points relating to, 201. Heaters, table of savings, 200. Purifier, description, 185. fire, thickness of, 40. What to do in case of, 40. Fire box iron, description, 88. Fire brick arcli in locomotive, 35. Fire clay, conducting power of, 213. Fire door, 237. Fire irons, 21. Firemen, advantages of trained, 24. Fire pails, use of, 21. Firing, trick of, 24. Boilers newly set, 28. With straw, description, 31. Duties of the fireman, 27. Ocean steamer, description, 32. Improper method, 27. Proper method, 26. With oil, description, 32. With coal tar, description, 30. Of twenty horse power, description, 30. Sixteen steam boilers, description, 29. With shavings, 33. With coke, directions, 28. Of steam boilers, 24. Under a boiler, gases and solids pro- duced, 16. With saw dust, 33. A. new plant, 37. With coal dust and screenings, 40. Firing with tan bark, 36. Boilers, experiments in England, 40. A locomotive, 35. Files, use of, 21. Fisli trap, 205. Fittings of marine boilers, 63. For boiler, specification, 87. Fixtures, boiler, description, 164. Flame, luminous, 41. Of anthracite coal, 16. Flange iron, description, 88. Flange of boiler liead« proper rad- ius, 103. Flanges for pipe, 248, Flanges, how to be turned, etc., 85. Flat surfaces in boilers, how to stay, 98. Flues and tubes, sweeping, 39. Flush front, description, 165-166. Foaming in boilers, 42. Four Avay cock, description, 273. Fronts, boiler, description, 165. Frost-bite, treatment of, 317. Fuel, loss of, by incrustation, 143. Fuel economizer, description, 186, Fuel-oil, 28y. Rules relating to, 290. Fuels, liquid and gas, 15. Table of comparative evaporative value, 18. Fullering, description, 94. Fulton, Robert, 11. Furnace, temperatufe of, 43. Fire, kindling of, 241. Chemistry of, 229, Dampers and doors, 39. Doors, description, 168-170. The, 237. Fusible plugs, description, 171, 173. Galloway boiler, description of, 58. Table of dimensions, 60. Gas, difference between it and a liq- uid, 216. As a fuel, 15. I'rom coal, comparative evapora- tion, 18. Dangers from, in idle boilers, 388. Amount burned in ventilating pipes, 265. Gasket cliisel, 308. Gas pipe, illustrations of size, 243. Gas pliers, description, 269. Gate valve, description, 273. Generators, steam, description, 48. Glass, specific heat of, 214. Radiating power of, 213. Glass guages, description, 177. Glass ivater guage columnsi ITT. Index. 325 Olobe valve, description, 272. Gold, radiating power of, 213. Conducting power of, 213. Grate, the, 237. Grate bars, description, 173. How to preserve from excessive heat, 38. Shaking grates, 174. How kept during firing, 27. Grooving of steam boilers, 126. List of cases, 125. Growth of the steam boiler, 52. Guage, steam, description, 181. Guage cocks, description, 176. Gaages, glass, description, 177. Guages, pressure i-ecording, descrip- tion, 233. Gusset stays, description, 100, 103. Hammer, water, description, 283. Pene, 306. Hammer test of rivets, 95. Hand-liole plates, description, 81. Hanger for pipes, 308. Hazards of fuel-oil, 289. Of the boiler room, 285. Heads of rivets, cup, conical, pan heads, 113. Head to liead brace, description, 103. Heat, laws of, 212. Unit of, 214. Specific, 214. How it becomes effective, 13. Heaters, feed water, description, 196. Heating, steam and hot water, 251. By exhaust steam, 267. Heat proof paints, 232. Heat stroke, treatment of, 315. High pressure steam, 283. Hinged valves, description, 272. Hoes, use of, 21. Homogeneous, definition, 121. Horizontal tubular boiler, de- scription, 79. Parts of, 81. Table of sizes, 77. Horse power, rule for estimating, 235. As applied to boilers, 234. Hose, rubber, use of, 21. Hot short, definition, 122. Howr to carry injured persons, 319. Hoiv to prepare for Inspection of steam boilers, 130. Hydrogen, specific heat of, 215. Description of, 230. Hydraulic test, 131. Ice, radiating power of, 213, Specific heat of, 214. Improper method of firing, cuts and description, 27. Incrustation of steam boilers, 143- 144. Example of, 142. And scale, list of cases, 125. Table showing quantity collecting, 103. Of boilers, " points " relation to, 149- 152. Individuality of each steam boiler, 25. Injector, description, 206. Injured persons, how to carry, 319, 320. Inspection of steam boilers, 129. How to make ready for, 129-130. Inspector's questions to applicant, 128. Inspector's rules relating to braces 102. Interceptor, steam, description, 183. Introduction, 10. Iron, T, description of, 103. (Hammered), melting point, 42. (Wrought), melting point, 42. Fire box, description, 88. Charcoal iron, description, 88. (Wrought), conducting power of, 213 Polished, radiating power of, 213. Specific heat of, 214. Melting point, 43. Flange, description, 88. Cast, conducting power of, 213. Irons, fire, 21. Issuing certificates of inspection^ 131. Jackscrew^s, description, 281. Jam brick, 237. Joints, putty, how to make, 303. Joints of lead pipe, 300. Joints of pipes, 248. Kerosene oil in boilers, " points **o£, 156-7. Kindling a furnace fire, 241. L, description, 274. liace cutters, use of, 21. Ladders, use of, 21. Ladle, 306. Lamp black, radiating power of, 213L Lancashire boiler, description, 55, Defects of, 55. Language of steam boilers, 39. Lanterns, use of, 21. Lap joint, illustration, 115. Laws of heat, 212. Lazy bar, description, 30. Lead, 299. S26 Index, liead, advantages iu use of, 399. Melting point, 42. Conducting power of, 313. Wrought, radiating power of, 213. Specific heat of, 214. Polished, radiating power of, 213. liead pipe, how to make putty joints, 304. Table of sizes and weights, 305. How to bend, 304. I^ead pipe joints, 300. Lever, length, rule, 193. Lifting valves, description, 273. Lime, definition, 138. Liquid, difference between it and a gas, 216. Litmus paper, definition, 153. Live steam, description, 383. Locknut, description, 374. Locomotive, firing of, 35. "Boiler compound, 149. Or charging shovel, description, 19, Locomotive boilers, description,73. How to rivet, 115. Locomotive portable boiler/ lescrip- tion, 80. Looking glass, 307. Loop (steam), description of, 378-.380i Low pressure steam, 283. LugS) specification of, 86. £iuminous flame, 41. magnesia, definition, 138. At what temperature deposited, 148. Carbonp*- "if, definition, 138. Malleable, definition, 121. raanhole cover, description, 81. I?£an1iole plates, specification, 86. marine boilers, description of, 60, How to rivet, 115. Fittings for, 63. Table of dimensions, 63. Super heaters, 64. Use of zinc in, 162. Blast pipe for, 63. Uptakes, 64. Parts which first give way, 112. Incrustation and scaling of, 146-147. Iflarine engineers, classification of, 310. Rules relating to, 309. marks on boiler plates, 88. marble, conducting power of, 213. materials, 12, 13. meckanical scraprrs, 187. mechanical stokers, 134-135. mercury, specific heat of, 214. Radiating power of, 213. TVeterS) water, description, 303. moisture in wood, 14. moutli piece, furnace, 336. mud drum, description, 179. Newly set boilers, how fired, 28. N ickel steel boiler plates, description, 91. Nipple, description, 374. Nitric acid, boiling point of, 37. Nitrogen, specific heat of, 215. Description of, 230. Non-conductors, 276. Noiseless water beater, 313, Ocean steamer, how to fire, 33. Oil, fuel, 289. Kerosene, in boilers, "points" of, 156-157. Specific heat of, 214. Firing with, 33. Ore barrow, use of, 30. Organic matter in water, how indi- cated, 154. Ornamental paints, 333. Overhanging front, description, 165-167. Overhead system of heating, 356. Oxide, definition, 136. Of iron, how best treated, 148. Oxygen, description of, 339. Specific heat of, 315. United with coal, 17. Paints, heat proof, 333. Palm stays, description, 100. Pan head of rivets, description, 113. Patch-screw, description and cut 123. Peat, description, 14. Analysis of, 13. Charcoal, description, 15. Comparative evaporation, 18, Pene hammer, 306. Petroleum, as a fuel, 15. Oil, comparative evaporation, 18, In boilers, use of, 155. Philadelphia Water Works ex ample of gain in good firemen, 35 Pipes, table of surfaces and capaci- ties, 246. Joints of, 248. How to weld, 264. Used for ice machinery, 263. Table of " data " relative to, 247. Pipes and piping, description, 344. Pipe coil, description, 257. Pipe couplings, 250. Pipe cutter, description and cut, 36ft Pipe hanger, 308. Pipe, gas, illustration of size, 343. Pipe tongs, description, 269. Index, 327 Pipe union, description, 274. Piping, dead end, 384. Piping and drainage, description and illustration, 299. Pitting of steam boilers, 126. Planer, (power), for boiler makers, 281. Plate, dead, description, 180. Quality of steel, 90. Plates, baffle, de;scription, 180. Burned and blistered, list, 125. For boilers, table of tbicknesses, 113. Pliers, gas, description, 269. Plug, description, 274. Plugs, fusible, description, 171, 172. Plumb-bob, description, 306. Plumber's solder, bow to make, 305. Plumber's tools, description, 306- 309. Solder, rule for making, 305. Plumber's wipe joint, 298. Plumbing, description and cuts, 298. What engineers should know, 298. *' Points " relating to firing, 37. Relating to boiler braces, 104. Of danger in steam boiler, 125. Relating to grate bars, 175. Relating to water gauge cocks, 176. Relating to glass gaugps, 177. Relating to the steam gauge, 182. Relating to safety valves, 194. Relating to feed water heaters, 201. Relating to water meters, 204. Relating to injectors, 209. Relating to pumps, 218-221. Relating to boiler setting, 239-241. Relating to steam heating, 254. Relating to chimneys and draught, 297. Poker, description and cuts, 19. Portable boiler, locomotive, descrip- tion, 80. Car track, use of, 20. Potter, Humphry, inventor of valve motion, 270. Poultices, how to make, 319. Power planer for boiler makers, 281. Power punch for boiler makers, 281. Precipitation of impurities in feed water, 144. Preface, 7. Preparation for firing steam boilers, 24. Pressure gauges, list of defective cases, 123. Regulator valve, 274. Pressure of safety valve, rule, 193. Principles relating to water, ^, Proper method of firing, cut and description, 21. Punch for boiler makers, 281. Pump, description, 215. Classification, 217. Parts of, illustration, 218. Double acting, 218. Direct pressure, 216. Calculations relating to, 222. Strainer for, description, 223. Points relating to, 218-221. Putty joints, how to make, 303. Questions of applicant for marine license, 127. Asked by examining engineers, 309. Of proprietor, relating to steam, boiler, 127. Radiant rays of heat, " point," 38. Radiating power of various sub- stances, 213. Radiation of heat, law relating to, 39. Railroad barrow, use of, 20. Ram, water, 284. Ratio of grate to heating surface, 175. Re-agent, definition, 136. Reamer, plumber's, 306. Recording pressure gauges, de- scription, 233. Reducing coupling, description, 274. Regulating the draught, 41. Regulations relating to marine engi- neers, 309. Regulators, damper, description, 185, Relief valve, description, 272. Repairing leaky tubes, 126. Repairs to boilers, " points " on, 124-ft. Riveting, modes of, 93. Specification for, 86. Description, 91. Double, description, 91. Chain, example, 93. Zig-zag, example, 93. Treble, example, 93. Unequal pitches, example, 93. Example of riveting boiler plates, 114-116. Hammers for boiler makers, 281. List of defective cases, 125. Rivet heads of cup, conical, pan heads, 113. Rivet heating machines, 281. Rivets, description, 93. Steel, description, 95. Table of diameters, 113. Rivet set, 307. Tests, 95. pivoted stays^ descriptloo, lOi, 328 Index, Rolls for boiler makers, 281. Rotary valves, description, 273. Round nose cblsel, 307. Rubber bose, use of, 21. Rule for estimating horse power of boilers, 235. For finding area of valve opening 195. To find pressure in lbs. of column of water, 223. To find area of steam piston of pump, 222. To find quantity of water elevated, 222. For finding contents of a barrel, 203. For reading water meters, 204. For making boiler and pipe cover- ing, 2T5-276. For making solder, 305. For finding strain on bolts, 99. For safe internal pressure, 117. For determining areas of steam boilers, 105. For calculating contents of steam and water in the steam boiler, 105. Rules, U. S., regarding safety valves, 189. For safety valves, 193. Inspectors, relating to bracing, 102. Relating tc fuel oil, 290. i'actory, to prevent accident, 293. Government, to prevent accident, 290. Before lighting the furnace fire, 25. Running of steam boilers under fire, 24. Safe internal pressure, rule and example, 117. Tables, 118-120. Safety factor of steam boilers, 96. Safety valves, description, 187. Rules, 191, 193. Rule to find area of opening, 195. Table showing rise of valve, 195. List of defects, 125. Points relating to, 194. Salt, definition, 138. Sand-bending of lead pipe, 304. Saturated steam, 283. Saw, compass. 308. Plumber"- s, 307. Saw dust, firing with, 33. As a fuel, 16. Sea water precipitator, 145. Sectional steam boilers, descrip- tion, 71. Sentinel valve, description, 184. Separator, steam, description, 183. set screivs, dangers arising from, 292 Setting of steam boilers, 236« Of water tube boilers, 239. Scalds, treatment of, 313. Scale deposited in marine boilers, anal- ysis, 146-147, Boiler, analysis of, 148. Scaling of steam boilers, "points,** 149-153. Scope of tbe ivorJk, 12. Scoop i^bovel, cut and description,19. Scrapers, mechanical, 187. Screenings, firing of coal dust and, 40. Screvr conveyors, use of^ 20. Screw-jacks, use of, 21. Screws stays, description, 301. Scum of boilers, how formed. 150. Scumming apparatus, descrip- tion, 161. Shaking grates, description, J74. Sbavings, firing with, 33. Blowers, use of, 20. Shearing strength, definition, ??i. Shears for boiler makers, 281. Shell of boiler, description, 81. Shovels, cut and description of. 19. Side brackets for boilers, 240. Silica, definition, 137. Silver, radiating power of, 213. Conducting power of, 213. Melting point, 42. Six inch Hue, boiler, 78. Slice bar, description and cuts, 19. " Point " relating to its use, 30. Smoke, insensibility from, treatmem 315. Snips, plumber's, 306. Socket bolts, description, 103. Soda, definition, 138. Proportion of, in water, 154. Acetate of, boiling point of, 37. Sodium, definition, 138. Solder, rule for making plumber's, 305. Sounds, or language of steam boilers^ 39. Source of powder in the steam en- gine, 13. Specifications for 125 H. P. steaia boiler, 85. Specific heat, description, 214. Table, 214. Spectacle piece, 124. Spirit level, 307. Stay bolts, hollow, description, 103. Staying of flat surfaces, 98. Stays and braces, list of defectiv** cases, 1?5. Index, 329 stays, gusset, description, 100. Of marine boilers, 75. Of locomotive boilers, 75. " Points " relating to boiler stays, 104. Palm, description, 100. 8crev/ed, description, 101, And brace, difference, 103. Table for calculations, 107-109. Steam, description, 282. Specific beat of, 215. Dry, 282. Dead, 282. Live, 282. Saturated, 283. Wet, 283. Higb pressure, 283. Low pressure, 283. Superlieatcd, 283. Specific gravity of, 283. Total heat of, 283. Steam and Iiot Avater lieatiiig,251. Steam boiler, growtli of the, 52. Water tube, 07. Sectional, description of, 71. Triple draught, 81-82. Six inch flue, 78. Two flue, 78. Steam boilers, locomotive, 72. Idle, dangers of, 288. Inspector's rules relating to bracing of, 102. Use of petroleum in, 155. Effect of sugar on, 150. Corrosion and incrustation, 142. Scaling of, "points," 149-152. Effect of bark on, 151. Bracing, 90. Specification for 125 H. P., 85. Steam drum or dome, description, 81. Steam fitter's vise, 269. Steam fittiiii2;s, care, 268. Description, 274. Steam gauge, description, 181. Steam generators, 48. Steam heating by exhaust, 267. How much space 1 H. P. will heat, 262. Steam loop, note relating to, 295. Description, 278-280. Steam pipe, linear expansion of, 276. Steam pipe explosions, 287. Steam pump, 215. St«'am separator, description, 183. Steam space of boilers, rule and example, 105. Steam \%'Iiistle, description, 180. Steel rivets, description, 95. Steel, boiler, description, 90. Melting point, 42. Speciflc heat of, 214. Steel iilates, nickel steel, descrip- tion, 91. Quality and thickness in, 85. Quality of, 90. Stephenson, George, 11. Stock and dies, use of, 21. Stolier, mecJianical, l:-{4. Storing coal, 225. Straightway valve, description, 273. Strainer, for pump, description, 223. Strain on bolts, rule and example, 99. StraAv, how best fired, 31. Comp sition of, as fuel, 15. Sugar, effect of, on steam boilers, 150. Sulphates, how indicated, 154. Definition, 137. Sulphate of lime, at what tempera- ture deposited, 148. Sulphur, description of, 230. Sulphuric acid, boiling point of, 37. Sunstroke, treatment of, 315. Superheated steam, 283. Superheater of marine boiler, 64. Surface blow off, description, 101. Surface condenser, description, 65. Swing valve, description, 273. Syphon, dangers from, in boilers, 288. T, description, 274. T irons, description and use, 103. Dimensions and shape, 104. Table of evaporation, 18. Melting points of metals, 42. Temperature, judged by color, 42. Of dimensions, Galloway boiler, 60. Of marine boilers, 62. Diameter of braces, 103. For calculating the number of stays, 107-109. Of dimensions of boiler tubes, 110. Holding power of boiler tubes. 111. Of diameter of rivets and thickness of plate, 113. Of safewinternal pressure, 118-120. Of defects found in steam boilers, 125. Showing loss at different thickness- es by corrosion, 143. Showing sediment collecting in boilers, 163. Showing rise of safety valve, 195. Of savings from use of feed water, 200. Capacity of cisterns, 202. Of specific heat, 214. 330 Index. Table of conducting power of various substances, 213. Of radiating power of various sub- stances, 213. Weigbt of cubic foot of water, 224. Weight and capacity of gallons of water, 225. Comparative quantity of water which can be evaporated, 231. Surfaces and capacities of pipes, 246. Of data relating to pipes, 247. Bursting pressure of tubes, 264. Of weights of round and plate iron, 309, 311. Conducting power of various sub- stances, 275. Relative value of non-conductors, 276. Weights of lead pipe, 305. Xan, description, 15. Tan bark, comparative evaporation, 18. Firing with, 36. Tanks for fuel oil, how to construct, 290. Tan-liqnor, unsaf^use of,li» bo-le«, 185. Tap borer, plumber's, 306, Taps and dies, description, i^9. Tee, description, 274. Temperature of a furnace, 42. Tensile strengtli of steel plate, 90. Of boilers, 121. Test, the hydraulic, 131. Testing-boiler, specification, 87. Testing boilers under steam press- ure, 287. Test pieces, description and illustra- tion, 105, 112. Tests for impurities in water, 153. Tests of steel rivets, 95. Thimbles, specification for, ^. Tliree Avay cock, description, 273. Tkrottle valve, description, 273. Tin, melting point, 42. Conducting power of, 213. Specific heat of, 214. Radiating power of, 213. Tissue paper, radiating power of, 213. Tongs for boiler makers, 281. Tool box, description, 22. Tools, plumber's, description, 306-30e. Handy for the fire-room, 21. Used in steam fitting, 269. Boiler maker's, 281. Plumber's caulking, 308. Torch, 307. Total heat t>f steam, 283. Tough, definition, 121. Trained oi untrained firemen, diflPer ence, 24. Trap, fish, 205. Treble riveting, example, 93. Triple draught tubular boiler, 83. Trevethick, Richard, frontispiece Tube expanders, 28i. Tubes, how to weld, 264. Table of bursting and collapsing pressures, 264. Boiler, illustration of size, 245. Experiments in holding power, 111. Table of holding power. 111. Boiler, table of dimensions, 110. Leaky, how to repair, 126. Tubes and flues, sweeping, 39. Tube sheets, description, 81. Turn-pin, description, 806. Two flue steam boiler, 78. Umbria, steamer, firing boilers, 32. Unequal riveting, example, 93. Union, description, 274. Unit of chimney measurements, 297. Upright steam boilers, descrij^ tion, 51. Uptakes of marine boiler, 64. Valve, gate, 273. Globe, description, 272. Brine, description, 273. Pop, description, 188. Angle, description, 273. Check, description, 273. Sentinel, description, 184. Pressure regulator, 274. Rotary, description, 273. Straightway, description, 273, Throttle, description, 273r Ball, description, 273. Chamber, description, 272. Double beat and double seat, 27^ Swing, description, 273. Valve bracket, description, 273. Valve cock, description, 272. Valve coupling, description, 272. Valves, description, 271. Safety, description, 187. Of what material made, 274. Valves, hinged, description, 272. Relief, description, 272. Back pressure, description, 273. Lifting, description, 274. Valves and cocks, description, 271, Valve-seat, description. 272. Vaults for fuel oil, how to constrac4 289. Ventilation, 265. Vise, steamfitter's, 368. Index, 33t Vises, use of, 21. M^ater, ho^v formed, 143. Principles relating to, 223. Principle temperatures of, 224. Point of maximum density, 224. The boiling jioiut, 224. The standard temperature, 224. Specitie heat of, 214. Boiling point of pure, 37. Radiating power of, 213. Conducting power of, 213. Freezing point, 224. IVater, (sea,) precipitator for, 145. Boiling point of salt, 37. Water bending of lead pipe, ;W. \*'atcr circulation, 21>4. W^ater grate bars, description, 17o. Gauge cocks, descrijition, 17G. ft ater lianinier, 283. V% ater meters, rule for reading, '^\ Description, 2tl3. f\'«ter ram, 2S4. Wiiter space of boilers, rule and ex- ample, ll^o. Water la^le xn locomotive, 35. ^ater ti&b^ fc.\.x\iu boiler, description, 67. ^W»i*er liPKter, noiseless. 313. "Water tube steam, boiler, setting of, 231\ Watt, James, 6. "Weiglkt of different standanl gallon? of water, 225. Of a column of air, 17. Weldable, definition, 121. "Welding boiler and other tubes, 2»H. "Wet steam, 28;i. "Wlieelbarrow, use of, 20. "Wliistle, steam, description, 18(1. "Wliitewasli, description, 232. AVI pe joint, how to make, 30(). Plumber's, 2118. Wood, comparative evaporation, 18. Specific heat of, 214. As a combustible, 14. "Hint as to drying," 14. "Wood cliarcoal, comparative ©vap oration, 18. AVood cbisel, 307. "Wounds, treatment of, 310. "Writing paper, radiating p<5wer of, 213. Zig-zag riveting, example, 93. Zinc, conducting p wer of, 21X Melting point, 42. Effect on corrosion of boilers, 15C Use in marine boilers, lfi2. Specific heat of, 214. o , .FOR. . » ENGINEERS, ^^}s£ Firemen, Electricians, Superintendents and all Steam Users. SEND ALL ORDERS TO TMEO. AUDEL 6t CO., 63 FIFTH AVENUE. Cor. I3tli Street, ^^^ ^^rk^ K z. X LIST. $2.00 each to any address. L Hawkins* New Catechism of Electricity, price post-paid, = - = = $2,00 IL Hawliins* Aids to Engineers* Examina^ tions, price post=paid, = - - 2.00 {With Questioyis and Answers.) ill. Hawkins Maxims and Instructions for the Boiler Room, price post-paid, 2.00 IV. Hawkins Hand Book of Calculations for Engineers, price post-paid, - 2.00 V. Hawkins" New Catechism of the Steam Engine, price post paid, = - 2.00 THE KEY to the contents of the Hawkins Books is to be fiULci in the carefully arranged Index in the end pages of each \ omtiit-. 1 he^e give access to any subject needed to be quick- ly coi ^ulttd Example : under " Accidents ' in the " Instruc- tions f-r the Boiler Room " are to be found a long list of reme- dits for burns, cuts, wounds, etc. X y z PERSONAL. For wise men the joys of reading are life's crowning pleas- ures. Books are our universities, where souls are the professors. Books arethe looms that weave rapidly man's inner garments. Books are t he levelers— not by lowering the great, but by lifting upthesm?ll. Newell Dwight Hillis in ''A Man's Value to Society.'''' Professor Hawkins has long been most favor- ably known as a practical and helpful writer upon Steam and Electrical Engineering, and now, as the publishers of his works, we take pleasure in handing you this little " booklet" describing the five books which comprise his scientific works issued up to the present time all of which are thoroughly up-to-date. We recommend them : To all who come in contact in any way with Steam or Electricity in any of its very numerous industrial departments. To anyone looking for advancement. 3. As books of standard reference on the subjects treated upon. Soliciting your kind patronage we are re- spectfully yours, I. 2. A^. Y. City, 63 5th Ave. \ -7 /L New Catechism of Electricity. A Practical Treatise. Price, $2.00. This is a book of 550 pp. , full of up-to-date information. 300 illustrations. Handsomely bound in red leather, pocket-book form, size 4^ X 6^, with titles and edges in gold. This book has been issued in response to a real demand for a plain and practical treatise on the care and management of electrical plants and apparatus — a book to aid the average man, rather than the inventor or experimenter in this all- alive matter. Hence this work will be found to be most complete in this particular direction, containing all the (book) information necessary for an ix- perienced man to take charge of a dymiiio or plant of any size. So important is the subject matter of this admirable work that there is only one time to or- der it and that is NOW, T ~ X / \ CONTENTS. The Dynamo ; Conductors and Non- Conduc- tors ; Symbols, abbreviations and definitions re- lating to electricity ; Parts of the Dynamo ; The Motor ; The Care and Management of the Dyna- mo and Motor. Electric Lighting ; Wiring ; The rules and requirements of the National Board of Under- writers in full ; Electrical Measurements. The Electric Railway ; Eine Work ; Instruc- tion and Cautions for Einemen and the Dynamo Room ; Storage Batteries; Care and Management of the Street Car Motor ; Electro Plating. The Telephone and Telegraph; The Electric Elevator ; Accidents and Emergencies, etc., etc. The full one-third part of the whole work has been devoted to the explanation and illustra- tions of the dynamo, and particular directions relating to its care and management ;— all the directions are given in the simplest and most kindly way to assist rather than confuse the learner. The names of the various parts of the machine are also given with pictorial illustra- tions of the same. In the Catechism no less than 25 full page illustrations have been given of the various dy- namo machines made in different parts of the country, and an equal number of part pap-e iV is- trations. ^ Bngi= neers Exami= nations with Ques= tions and An= swers. Price $2.00, The volume is bound (being designed for constant and ready reference ) in substantial red leather with titles and edges in gold; it consists of between 200 and 300 pages, printed on heavy, fine surface paper; size 5''''x7>^^''; weight I }4, lbs. This book is a most important aid to all engineers, and is undoubtedly the most helpful ever issued relating to a safe and sure preparation for examination. It presents in a condensed form the most approved practice in the care and management of Steam Boilers, Engines, Pumps, Electrical and Refrigerating Machines. The following is a complete list of its contents: TESTIMONIAL.-FRED. D. STONE, "Inclosed find $2.00 for Hawkins' New Catechism of Electricity. I have HAWKINS' AIDS TO ENGINEERS EXAMINATIONS. It is the best on the subject. I owe my success in securing a license to it. ^ } / N ^ Contents. 1. This book embraces information not else where obtainable. 2. It tells exactly what an engineer will have to go through in getting a license, with much kindly and helpful advice to the applicant for a license. 3. It contains the annual report of the superin- tendents of "Steam Boiler Inspection and Certifica- tion of Engineers ' for the cities of New York and Brooklyn. 4. It contains various rules, regulations and laws of cities for the examination of boilers and the licensing of engineers. 5. It contains the laws and regulations of the U. S. for the examination and grading of all marine engiircers. 6. It gives a short chapter on the "Key to Suc- cess " in obtaining knowledge necessary for advance- ment in engineering. This is very important. 7. The book gives the underlying principles of steam-engineering in plain language, with sample questions and answers likely to be asked by the examiner. 8. It gives a few plain rules of arithmetic with examples of how to work the problems relating to the safety valve, strength of boilers and horse power of the steam engine and steam boiler. 9. The main subjects treated, upon which are given detailed information with questions and answers are as follows:— The Steam Boiler, Boiler Braces, incrustation and Scale, Firing of Steam Boilers, Water Circulation in Boilers, Constrviction and Strength of Boilers, The Steam Engine, Engine and Boiler Fittings, Pumps, The Injector, Electricity and Electric Machines, Steam Heating, Refrigera tion, Valve Setting, etc., etc. X Maxims and Instructions for the Boiler Room, Price $2.00. This book is uniform in binding and size with "Calculations for Engineers" and the "New Catechism of the Steam Engine" ; the size is 6x8^ inches, i% inches thick; weight 2 lbs. ; and bound in green silk cloth, gilt tops and titles in gold; it has 331 pages with 185 diagrams or illustrations. This is of all the Hawkins books perhaps the most useful to the Engineer-in-charge, to the Fireman, to the Steam user or owner, and to the student of Steam Engineering — FOR — The work relates to Steam Generators, Pumps, Appliances, Steam Heating, Practical Plumbing, etc., etc. X z. CONTENTS. Fire Irons ; The firing of Steam-boilers ; A Chapter of "Don'ts" relating to firing; Steam-boiler ; the History and Growth of the Steam-boiler ; Upright Boiler ; the Marine Boil- er ; The Water-tube Boiler ; The I^ocomotive Boiler ; The Horizontal Tubular Boiler ; Parts of the Boiler; Specification for 125 H. P. Boil- ers ; Construction, Riveting and Bracing of Boilers, with many illustrations and tables for calculating the strength of same ; Boiler Makers' Tools ; Boiler Fixtures and belongings ; Plumb- ing; Piping; Accidents and Emergencies; In- dex with nearly 1,000 References, etc., etc. No Engineer, Fireman or Steam User can afford to BE WITHOUT THIS VALUABLE BOOK, AS IT CONTAINS THE PITH AND VITAL "points" OF ECONOMICAL AND SAFE STEA M PRO- DUCTION. The PLAN FOLLOWED IN THIS WORK IS THE SAME AS THAT SO GENERALLY APPROVED IN "CALCULATIONS " ; IT PROCEEDS FROM THE MOST SIMPLE RULES AND MAXIMS TO THE HIGHEST PROBLEMS ; IT IS BOTH A BOOK OF INSTRUCTION AND REFER- ENCE. The CAREFULLY-PREPARED InDEX CONTAINS NEARLY ONE THOUSAND REFERENCES, THUS MAKING IT ALMOST A DIC- TIONARY OF TERMS. X z X Hand Book of Calculations for Engineers. Price $2.00. THIS IS A WORK OF INSTRUCTION AND REFERKNCE REI