ir 
 
 Brake 
 Catechism 
 
 BY 
 
 aQ 4 fa^inMfrcr* 
 
 Twenty Fourth Edition 
 
Class. 
 Book. 
 
 
 9 
 
 Showing ,l DE 
 EYE LOCOM 
 TOR with"BEl 
 DER LUBRIC 
 Feed, and Wes 
 
 Copyright^ . 
 
 COPYRIGHT DEPOSIT: 
 
 ) 
 
 "DETROIT" 
 
 SIGHT -FEED 
 
 AIR CYLINDER 
 
 LUBRICATOR 
 
 Insures the proper lubrication of the 
 Air Cylinder of Locomotive Air Brake 
 Pump. Provides complete and conven- 
 ient control of Air Cylinder Lubrica- 
 tion from Engine Cab. Guarantees the 
 application of just the right quantity of oil at the right time. It's 
 simple — consists of 3 features — the Emergency Valve "H" Sight 
 Feed Fitting "K" Check Valve Connection "S." Approved and highly 
 recommended by leading Railway Mechanical Experts. Send for 
 our Locomotive Lubricator and Air Cylinder Catalog* and 
 Instruction Book "R," it's free. 
 
 D etroit L ubricator P om pan y , 
 
 DETROIT, U. S. A. 
 
 Double Feed Type 
 
THE 
 
 Air Brake Catechism 
 
 AND 
 
 Instruction Book 
 
 On tho Construction and 
 Operation off 
 
 THE WESTINGHOUSE 
 
 AND 
 
 THE NEW YORK 
 
 AIR BRAKES 
 
 With a List of 
 
 Examination Questions for Enginemen 
 
 and Trainmen 
 
 By 
 
 Copyright by C. B. Conger, Grand Rapids, Mich. 
 1910. 
 
 Twenty Fourth Edition 
 
*° 
 
 <*v 
 
 PREFACE 
 
 24th Edition 
 
 In this enlarged edition of the Air Brake Catechism 
 considerable new matter has been added which will prove 
 of interest not only to those who are learning about the 
 operation of the brake equipment from their own observa- 
 tion and experience, but to those who have the advantage 
 of an instruction car with a regular instructor. This 
 subject of self-instruction in all its details is so large that 
 only a small part of it can be taken up in this little book, 
 but the principal points are brought to notice. 
 
 The work done by the air brake operator in handling 
 trains is becoming more skillful every year; he who 
 wishes to keep up with the best practice must continually 
 try to improve his work. This can only be done by learn- 
 ing and practicing the best methods. Bear in mind that 
 good judgment is the first requisite for a successful air 
 brakeman, the addition of knowledge of the construction 
 so as to locate defects and their remedies, and correct 
 methods of handling, to good' judgment, will make a 
 skillful man under all conditions. 
 
 At the present day every one connected with the work- 
 ing of the air brake is expected to pass regular examina- 
 tions, and these examinations are getting more strict each 
 year. The list of examination questions will call atten- 
 tion to points in the construction and handling of the 
 brake which you should know 'if; you wish to pass. 
 
 The construction and operalfon of the air pump, brake 
 valve and triple valve, as far as it interests enginemen, is 
 explained, the matter of repairs is not taken up. 
 
 All the new designs of locomotive and high duty car 
 brakes of both Air Brake companies that are in general 
 service at this date are explained in this Catechism. 
 
 OttA8-59276 AAt\M\ 
 
INTRODUCTION 
 
 At the present day so much depends on the proper 
 handling of the Automatic Brake that a definite knowledge 
 is required from all men in train service of its operation 
 when in good order, and how to locate defects or break- 
 downs, as well as how to avoid the difficulties arising from 
 them. 
 
 This applies to the veteran as well as to the beginner. 
 The changes in the mechanism, caused by the new and 
 improved devices brought into service to take care of 
 longer freight trains and faster passenger trains, as well 
 as the devices for independent operation of the locomotive 
 brake, call for study on the part of the men who have 
 handled the brake for years, for a passenger train of 
 moderate length equipped with ordinary triple valves 
 and a long train with all high speed brakes are two 
 widely different propositions, and the veteran looks for 
 information on them. As for the beginner, he can not 
 learn it all from experience, as no one is allowed to 
 handle important trains until he has shown, either by an 
 examination or by handling a moving train under the 
 supervision of some man who can judge, that he has 
 the necessary knowledge to properly operate the brake 
 under all ordinary conditions. 
 
 This has brought about a demand for a clear and prac- 
 tical form of instruction in air brake practice, not so much 
 to instruct the beginner on all the points as to put him in 
 the way of learning them himself; and this introductory 
 chapter is intended to help those who set out to learn the 
 theory and have a chance to operate the brake or see it 
 operated. This can best be done by learning the foun- 
 dation principles first, studying the action of the important 
 primary parts of the machine; the secondary parts will 
 then work their way in so you understand the whole 
 properly. Much time may be wasted by beginning at the 
 
4 SELF INSTRUCTION 
 
 wrong end to unravel air brake operations. If you are 
 too hasty and jump at conclusions, you may be wrong; 
 better not know anything about it than know it wrong. 
 Therefore, take time enough at first to learn it right; 
 you will never regret it. 
 
 There is nothing mysterious about the operation of the 
 air brake. Each part has its own duty to perform. Take 
 each part by itself and study it up, then get an idea of its 
 relation to the other parts, and you will find out that it is 
 easy. You cannot learn it all at once, or by once reading 
 over an instruction book. In studying the construction 
 and principle on which it operates, it is an advantage to 
 have help from some one who can instruct you. When 
 you come to operate it, the machinery in actual operation 
 Is the best instructor. 
 
 When you see the air brake working every day, some- 
 limes making -a good stop, at others not controlling the 
 train as you think it should, the operation may seem 
 mysterious, but it is governed by fixed laws of mechanics 
 and forces. If you take pains to learn these laws and 
 about the forces, and examine each part of the mechanism, 
 it will be clear to you. 
 
 Attention is called to explanations of some of these 
 operations in the succeeding pages of the Air Brake Cate- 
 chism. Many of these operations are explained in more 
 than one manner in connection with the movements of 
 •other parts of the apparatus. 
 
 In the first place, all the parts of the brake which are 
 named in question 1 of the Catechism, are charged with 
 compressed air, which comes from the air pump to the 
 •main reservoir, then through the ports in the brake valve 
 Into the brake pipe and triple valve, from there it passes 
 through the feed port in the triple valve into the auxiliary 
 reservoir provided for each complete brake. When the 
 "brake is ready to operate, the pressure is equal in the 
 brake pipe, in the triple valve on both sides of the triple 
 piston, and in the auxiliary reservoir. When you change 
 the relation of these pressures in different parts of the 
 
PLAIN TRIPLE VALVE 5 
 
 equipment, the effort the compressed air makes to equalize, 
 by the high pressure air pushing against the low pressure 
 air, moves the different parts of the air brake that can be 
 moved in this manner away from the high pressures. 
 
 When it is once fixed in your mind what pressure you 
 have in each place, and that any change of pressure will 
 cause the movable parts of the valves to change their 
 positions, closing some of the openings through which the 
 air can pass and opening others, it is plain that the next 
 step is to find out just what openings the air must pass 
 through at each operation, whether applying or releasing 
 the brake, always remembering that the high pressure air 
 tries to flow into a space of lower pressure. 
 
 When studying the equalizing processes in the operation 
 of compressed air equipment, remember that it is air that 
 flows from one part of the equipment to another and not 
 pressure. Pressure is only a condition, air is a substance 
 or material. A substance can flow from one cavity or 
 receptacle to another, but a condition can not flow through 
 an opening. When compressed air flows from any part of 
 the equipment to another, as from the auxiliary to the 
 brake cylinder, it will change the conditions or pressure 
 in these places, but the pressure does not flow either way. 
 
 It will take away much of the mystery of equalization 
 if you will bear these facts in mind. 
 
 We will take up the plain triple valve first, as the 
 process of equalization is best explained with it. Yon 
 will notice in the cut on next page of the plain triple valve 
 in the position for charging the auxiliary reservoir and 
 exhausting the air from brake cylinder, that the triple 
 piston 5 is the dividing line when the pressures are 
 unequal; that the brake pipe pressure is against the lower 
 side of this piston and auxiliary pressure on top. There is 
 a small passage cut in the side of the cylinder around the 
 piston, called a feed port, at m, through which air can 
 pass from the brake pipe around the piston 5, and up 
 beside the slide valve 6 into the auxiliary at Y, when triple 
 piston is clear up in release position; this is the opening 
 
PLAIN TRIPLE VALVE 
 
 through which air can equalize in brake pipe and auxiliary. 
 The piston acts as a valve to open and close this feed port. 
 This port m is very small, and equalization takes place 
 slowly through it. A brief explanation of the reasons for 
 its small size is found farther along in the book. 
 
 As the auxiliary stores the compressed air used for 
 applying its own brake, it must first be charged with a full 
 
 i PiPE TAP 
 
 OF.TAILS 
 
 Triple-Valve Body 
 Cylinder Cap. 
 Cap Nut. 
 Piston 
 Slide Valve. 
 Graduating Valve. 
 Graduating Stem. 
 Graduating Spring. 
 Graduating-Stem Nut. 
 Cylinder Gasket. 
 Packing Ring. 
 Bolt and Nut. 
 Slide- Valve Spring. 
 
 RELEASE AND EXHAUST POSITION. 
 
 supply of air; which will raise its pressure to the stand- 
 ard — usually 70 pounds — and it takes about a minute and 
 10 seconds for air enough to flow around the piston to 
 equalize the pressure at 70 pounds. To apply the brake 
 with a triple valve the brake pipe pressure must be re- 
 duced. As soon as any reduction of pressure is made in 
 the brake pipe the auxiliary pressure will be greater and 
 
SERVICE APPLICATION 7 
 
 force the triple piston down, following the decrease of 
 pressure in brake pipe end of triple. 
 
 This first movement of the piston does not set the 
 brake. There is some slack between the collar on the 
 piston rod and the top of slide valve 6 — about five thirty- 
 seconds of an inch — a very slight reduction of pressure 
 under the piston moves it down the amount of this slack, 
 
 SERVICE APPLICATION. 
 
 LAP POSITION. 
 
 closing feed port m and pulling graduating valve 7 off its 
 seat in slide valve. As the slide valve has the auxiliary 
 pressure holding it on its seat, more change of pressure 
 under the piston is needed to move the slide valve — a 
 point to remember when you move the triple valve to 
 release position. When the piston comes down, bringing 
 with it the slide valve, a port z, leading from the seat 
 of graduating valve 7, is opened to f, allowing the 
 
8 SERVICE APPLICATION 
 
 auxiliary air to pass from the graduating valve into the 
 brake cylinder. This also has a movable piston that 
 pushes against levers which are so coupled up that the 
 brake shoes are forced against the wheels. The operation 
 of this triple piston with a moderate reduction of brake 
 pipe pressure, say from 70 pounds down to 63, will show 
 the exactness of this equalization principle. 
 
 When the triple piston 5 comes down, following a 
 reduction of 7 pounds in the brake pipe (and the piston 
 does not wait till the entire reduction of 7 pounds is 
 made), and slide valve 6 and graduating valve 7 opens, 
 the air in the auxiliary at 70 pounds begins to expand 
 into the brake cylinder, as shown in cut of service appli- 
 cation. As soon as enough air has gone into the cylinder 
 to reduce the auxiliary pressure a little below 63 pounds, 
 the brake pipe pressure is then greatest; hence triple 
 piston moves up, also moving the graduating valve 7 
 and closing it. This cuts off the flow of air into the 
 brake cylinder. As only a part of the full supply of air 
 has passed into the brake cylinder, it sets the brake with 
 a partial application and holds it set, for the piston does 
 not move the slide valve 6 up and open the exhaust port 
 k to air port f, as shown in cut of release position. For 
 a more detailed statement of the operation of the graduat- 
 ing valve, see the answer to a question farther along in 
 this book. Thus you see the triple piston moves between 
 the brake pipe and auxiliary pressures, always towards 
 the lesser one. 
 
 A graduating stem 8 and its spring o, in the bottom 
 case of the triple, serve to stop the piston at a point in its 
 travel where port z will be exactly opposite port f. This 
 stem and spring are not moved in a partial service appli- 
 cation, because when these ports are wide open the air 
 will pass from the auxiliary to the cylinder as fast as it is 
 going out of the brake pipe, this will reduce the auxiliary 
 pressure as fast as the brake pipe pressure reduces. 
 
 If the relations between the pressures on either side of 
 triple piston are changed, it will move toward the lower 
 
RELEASING BRAKES 
 
 9 
 
 pressure until the limit of its travel is reached, or until 
 the relation between the pressures is changed the other 
 way; this will stop its movement if pressures are equal- 
 ized, or move it the other way if pressure is increased. 
 Increasing the pressure in brake pipe side of triple over 
 the auxiliary moves the triple piston clear up, moves the 
 slide valve 6, opens exhaust port k to air port f, allows 
 
 The plain triple valve 
 moves to this position 
 when the train pipe pres- 
 sure is lower than the 
 equalizing pressure of the 
 cylinder and auxiliary 
 either with a quick or a 
 slow reduction. 
 
 EMERGENCY APPLICATION. 
 
 the air to escape from brake cylinder and releases the 
 brake; so you see, charging up the brake pipe to standard 
 pressure releases the brake. As the feed port m is also 
 opened when the piston 5 is clear up, the air flows into 
 auxiliary, equalizing its pressure with the brake pipe. To 
 change the relations between the pressures in any other 
 way is done by letting out some of the air— the train man 
 
10 EMERGENCY APPLICATION 
 
 releases the brake by bleeding out the auxiliary pressure 
 until it is lower than brake pipe pressure. 
 
 If a reduction of the brake pipe pressure of more than 
 20 pounds is made, as from 70 to below 50, the auxiliary 
 pressure must also be reduced 20 pounds or more before it 
 will allow the piston 5 to move up and close the graduating 
 valve. 
 
 The brake cylinder is of such a size — if it has the 
 proper piston travel — in proportion to the auxiliary reser- 
 voir that if air is allowed to flow from the auxiliary into 
 the cylinder it will equalize in both of them at about 
 five-sevenths of the original pressure, which is 50 pounds 
 in case of 70 pounds originally. After this equalization 
 has taken place no more reduction of pressure will be 
 made in the reservoir, except by a leak or at the bleeder 
 and the triple piston will move clear down to the position, 
 which with a gradual service application is called full 
 application position. This is the same as the emergency 
 application position. You will notice the slide valve has 
 uncovered the air port f so air can pass through freely 
 and hold the brake cylinder pressure equal to the auxiliary 
 pressure. The stud or post on the bottom of triple piston 
 has pushed the graduating stem 8 down, compressing its 
 spring o. This spring helps to stop the piston 5 at the 
 proper place with a partial service application and assists 
 in starting the piston up to release after a full application. 
 
 After thoroughly posting yourself on the way in which 
 the plain triple operates by the reduction or equalization 
 of pressures, you can then take up the engine equipment. 
 It is a good plan to know just how the pump operates, its 
 care and management, but that can be left till later; it is 
 treated of farther along in this book. The pump generally 
 goes ahead with its work from beginning to end of the 
 trip without much attention from the engineer; the rest 
 of the equipment depends on the skill and knowledge of 
 the engineer for its successful operation, as it responds 
 directly to his manipulation. 
 
 The brake valve controls the passage of air between the 
 
THE BRAKE VALVE 11 
 
 main reservoir and brake pipe or brake pipe and the 
 atmosphere. 
 
 The main reservoir air pressure is always in the top of 
 the valve holding the rotary valve 13 on its seat; the 
 brake pipe air is under the equalizing piston 17 at all times. 
 The air over the piston can be called brake-valve air. 
 Brake valve and brake pipe air can equalize when the 
 rotary is on running position, and in full release. This is 
 further explained in detail later on. The equalizing 
 piston 17 is moved up, opening the discharge or brake 
 pipe exhaust port n, or down, closing the port, by a change 
 of pressure on either side, just the same as the triple 
 piston. The presures are changed by opening or closing 
 the various ports in the valve. Opening preliminary 
 exhaust port h reduces the pressure over piston 17 so that 
 brake pipe pressure raises the piston; brake pipe pressure 
 reducing through port n brings piston down. The rotary 
 13 is moved by the engineer, its office is to put in com- 
 munication the various openings or ports that will let 
 the air pass through. Locate these ports, next find out 
 just what they are for and in what positions of the rotary 
 they are open and shut. The best way to do this, if you 
 have no sectional valve to study on, is to get a complete 
 valve for a few hours and dissect it, using a piece of fine 
 copper wire to run through the ports, which will show 
 the course of the air; this wire can be bent in any direc- 
 tion and its use is not likely to scratch the seats or valve. 
 After locating all the ports through which main reservoir 
 air can flow into brake pipe or the chamber D over piston 
 17, then see in what position of the rotary all ports are 
 covered, and figure out which ports are covered first and 
 why it is necessary to stop the flow of air through them. 
 
 You will probably notice that before any ports are 
 opened to allow air to escape from the brake pipe the main 
 reservoir air is cut off from the brake pipe, so it can not 
 supply the brake pipe while you are reducing that. Other- 
 wise the triple valve would not feel any reduction of pres- 
 sure and brake would not be set. Then when you come to 
 
THE BRAKE VALVE 13 
 
 ' locate the ports that are opened to reduce the brake pipe 
 pressure and actuate the triple, it will be necessary to 
 know just exactly the principle of operation of the equal- 
 izing discharge valve. 
 
 On a long train the reduction of brake pipe pressure 
 must be the same at each triple if we expect each brake 
 to be set at the same time and with the same relative 
 power. To make this reduction of pressure alike for all 
 the triples, or what is the same, for all the cars in the 
 train, we must allow the air to escape from the brake 
 pipe gradually so the reduction will not be any more 
 violent from the first car than from the last one, nor 
 should the escape of air be closed till the same reduction 
 has been made in each car. The discharge should not be 
 stopped suddenly before the pressure in the last cars has 
 equalized with the first ones, or the momentum of air 
 flowing from rear cars, as well as equalizing pressures in 
 all cars, will raise the brake pipe pressure in the cars 
 nearest the brake valve and tend to release their brakes. 
 This gradual closing of the brake pipe exhaust, the brake 
 valve is intended to do automatically. Its principle of 
 operation is, the engineer makes the proper reduction of 
 pressure in the brake valve over the equalizing piston 17, 
 and the action of the piston 17 reduces the brake pipe 
 pressure to an equal amount in all the cars, whether few 
 or many. 
 
 Before you move the rotary far enough to open the 
 preliminary exhaust port h, the equalizing port g, which 
 allows brake pipe air to pass from brake pipe to chamber 
 D, over piston //, is closed ; this cuts off chamber D from 
 any other pressure ; you can then make a reduction on top 
 of piston 17, so brake pipe pressure will raise it up and 
 hold discharge n open till the pressure below is a little 
 less than it is above, when piston is moved down by the 
 chamber D pressure, closing brake pipe discharge. 
 
 With the equalizing discharge valve, the black hand 
 of the double gage is connected with chamber D at all 
 times ; if the rotary is in either full release or running 
 
14 THE BRAKE VALVE 
 
 position the equalizing port g connects it to the brake pipe 
 air so it shows that pressure also. When the brake is set 
 with a service application, the pressures equalize so nearly 
 on each side of piston at the instant brake pipe exhaust 
 closes that the black hand is expected to show brake pipe 
 pressure then also. In the emergency position the black 
 hand does not at once show the amount of the reduction. 
 You will find this further explained later. 
 
 If the packing ring in piston if leaks very much, the 
 black hand will show brake pipe pressure when rotary is 
 on lap, as the air pressures can equalize past this leaky 
 packing ring; all of them leak a little. There is a leather 
 gasket above this piston to prevent leakage during a serv- 
 ice application, but not when the piston is in normal 
 position. Look out for this defect when operating the 
 brake. The brake valve reservoir is connected with the 
 valve for the purpose of giving a larger volume of air to 
 chamber D in order to insure a gradual reduction of 
 pressure there. 
 
 Up to this point we will assume that the student has 
 followed the action of the brake in a service or graduated 
 application. There is what we call the emergency or quick 
 action, produced by a different set of operations peculiar 
 to the quick action triple valve only. We will, go to the 
 beginning and inquire why this action is necessary. 
 
 On a long train of air braked cars, to avoid a severe 
 shock to the rear part of train when brakes are applied 
 from the head end of train very suddenly, as by bursting 
 a hose or breaking apart of the train, or in case of danger 
 when it is necessary to set the brake from the engine very 
 hard so as to stop as quickly as possible, the brakes should 
 set on the rear cars quicky enough so the slack will not 
 run up against head cars and damage cars or draft gear. 
 Then, in case of danger, every second after the brake is 
 applied at the engine before it begins to set on last cars 
 and hold them, the train is getting nearer the danger; so 
 a brake that can be set instantly on the whole train will 
 stop the train quicker than one which sets slowly from car 
 
THE TRIPLE VALVE 
 
 15- 
 
 to car. With the plain triples the air in brake pipe will be 
 exhausted at one place only, either where an opening is 
 made in brake pipe or at brake valve ; this takes several 
 seconds to affect the farthest car. If an opening can be 
 made to exhaust this air at each car and reduce the brake 
 pipe pressure, the action of the brakes on a long train can 
 be made nearly simultaneous, so nearly so that the brakes 
 are all set before the slack can run out. The quick action 
 
 DBTAILS. 
 
 2 Triple valve body. 
 
 3 Slide valve. 
 
 4 Piston. 
 
 6 Slide-valve spring. 
 
 7 Graduating valve. 
 
 A 
 
 'JO TRAIN PIPE 
 
 8 Emergency-valve piston, 
 
 9 Emergency-valve seat. 
 
 10 Emergency valve. 
 
 11 Rubber seat. 
 
 12 Check-valve spring. 
 
 13 Check-valve case. 
 15 Check valve. 
 
 21 Graduating stem. 
 
 22 Graduating spring. 
 
 QUICK -ACTION TRIPLE VAI<VE — RELEASE POSITION. 
 
 triple is designed to exhaust a portion of the brake pipe air 
 
16 QUICK ACTION TRIPLE VALVE 
 
 at each triple, so as to set the next brake suddenly. To 
 thoroughly understand how the quick action triple can 
 exhaust some of the air from the brake pipe suddenly and 
 reduce the pressure so as to affect the next triple in the 
 same manner, it will be necessary to study the construction 
 of the quick action valve. This triple has the same open- 
 ings to admit air from the brake pipe to the auxiliary that 
 we find in the plain triple. In the quick action triple they 
 are shown at e through g and feed port i. But there is 
 another channel for air to pass from the brake pipe into 
 the brake cylinder in this valve, which is from the check 
 valve case 13 into y, then into x and into brake cylinder at 
 C. These openings are ordinarily kept closed to the pass- 
 age of the air in either direction; the rubber seated emer- 
 gency valve 10 keeps the brake pipe air from getting into 
 the cylinder, and the check valve 15 keeps the air in brake 
 cylinder from getting back into brake pipe. These two 
 valves are held on their seats by a spring, shown at 12, as 
 well as by the air pressures. Now it follows that, if you 
 wish this triple to make an opening to let the air out of 
 brake pipe suddenly, this valve 10 must be moved away 
 from its seat against the brake pipe pressure and the strain 
 of the spring 12. For this purpose piston 8 is used. A 
 port t, which is shown just over the figure 8, can be 
 opened by the slide valve 3, letting the air from the auxil- 
 iary on top of piston 8; with auxiliary reservoir pressure 
 over this piston and no pressure at all or a very low one 
 below it, piston 8 goes down instantly, forcing valve 10 
 away from its seat. The brake pipe air then moves check 
 15 up and flows through C into brake cylinder till press- 
 ures equalize. 
 
 When these valves 10 and 15 are opened in this manner, 
 the brake pipe air goes past them like a flash through the 
 large ports into the empty brake cylinder, setting the 
 brake with the pressure at which the brake pipe and brake 
 cylinder can equalize, which is somewhere near 20 pounds. 
 At the same time port s, in the end of slide valve 3, is 
 open, air from auxiliary flows through r and piles in on 
 
QUICK ACTION TRIPLE VALVE 17 
 
 top of brake pipe air in cylinder, raising the cylinder press- 
 ure at full equalization to 60 pounds. The brake pipe air 
 equalizes first with cylinder, through large ports, and 
 auxiliary pressure last, through small ports. Considerable 
 air passes around piston 8, which is not an air tight fit 
 in its bushing. 
 
 Now for the means employed to let auxiliary reservoir 
 pressure on top of piston 8 at one time to produce "quick 
 action" and keep it out at another to preserve the grad- 
 uated application. As long as this triple is used with a 
 graduated application, slide valve 3 does not move ovefr 
 far enough to uncover emergency port t, as with a gradual 
 reduction of brake pipe pressure auxiliary presure will 
 be reduced equally with brake pipe pressure through the 
 graduating valve 7 and its port 2. The graduating stem 
 21 and its spring 22 ordinarily stop the movement of the 
 piston 4 when it reaches the service application position. 
 But if brake pipe pressure is reduced so suddenly and to 
 such an amount that the graduating valve can not reduce 
 auxiliary pressure equally with brake pipe reduction, and 
 graduating spring does not stop the piston, the greater 
 auxiliary pressure will move piston 4 and slide valve 3 
 far enough so port t will be uncovered, auxiliary air will 
 move piston 8, valves 10 and 15 will move at once and 
 "quick action" is the result. The Westinghouse Co. have 
 made a quick service triple valve that allows a small 
 quantity of brake pipe air to flow into the brake cylinder 
 during a service application and another type that uses 
 air from a supplementary reservoir. These will be de- 
 scribed later on in this book. 
 
 A sticky triple valve or any defect in valve 7 that will 
 prevent air getting past it will cause quick action opera- 
 tion with a moderate service application if you have a 
 short train. The equalization of pressures is the founda- 
 tion principle to look for in the operation of the quick 
 action triple. 
 
 It is necessary to restrict the flow of air through some 
 of the openings in triples and brake valve in order to be 
 
18 EQUALIZATION 
 
 sure to handle a long train with safety. This refers more 
 particularly to the "feed ports" in the triples for recharg- 
 ing auxiliaries, the "preliminary exhaust port" h, train 
 pipe exhaust n and exhaust ports in triple valves. The 
 proper size of these ports has been determined by the 
 experience of many years. 
 
 Perhaps it would be well to study on the matter of 
 equalization of different pressures of air in the equipment, 
 as if this is well understood you can solve other problems 
 in air brake operations more easily. It is the law that 
 where compressed air in a certain sized vessel expands into 
 an empty one, the pressure is reduced in the full one in 
 proportion to the increased volume the air has to occupy. 
 From this you can see that in the case of the brake cylin- 
 der and auxiliary the auxiliary pressure will be reduced 
 more if the brake cylinder is large in proportion to the 
 auxiliary than if it is small. Apply this law to the cylin- 
 ders having different piston travels; a cylinder having a 
 long piston travel holds a greater volume of air than the 
 one with short travel, so we can expect the one with long 
 travel to reduce the auxiliary pressure to a lower point 
 than the short travel, and it is found that a travel of 11 
 inches of the freight brake piston gives a final equalized 
 pressure of close to 45 pounds, while a short travel of 8 
 inches, which is between 4 and 11 inches, will give a final 
 equalization of about 50 pounds. The difference of press- 
 ures with long and short piston travels is more marked 
 with partial applications than with full equalization . A 
 5 pound reduction of auxiliary pressure will give about 18 
 pounds per inch on a piston with 4 inches travel; while 
 with the 11-inch travel piston, the pressure will not show 
 anything. This will give different brake powers on dif- 
 ferent cars in the train, although it should be equally 
 proportioned to the weights of the cars ; unequal brake 
 power makes some cars hold less than others, so the strain 
 is not equally distributed throughout the train, a point 
 in equalization worth studying on. 
 
 The final point at which auxiliaries and their cylinders 
 
EQUALIZATION 19 
 
 equalize cuts quite a figure in operating the triples to 
 release the brakes. A variation in piston travel of the 
 different brakes changes this point of final equalization 
 and will be explained later. As was stated in explaining 
 the operation of the triple piston, the brake pipe pressure 
 must be greater than the auxiliary pressure to move the 
 triple piston up so slide valve will open exhaust port and 
 let air in brake cylinder equalize with the atmosphere; 
 then the brake piston will have no air pressure on either 
 side of it. This relieves the strain on brake levers and 
 shoes. 
 
 If auxiliary pressures on this final equalization are 
 unequal and brake pipe pressure is not raised at once 
 higher than the highest auxiliary pressure, all the brakes 
 will not release at once. This leads us to consider the 
 question of equalization of the train pipe and main reser- 
 voir pressures when you desire to release the brakes. 
 
 If the brake pipe is long it will take more air from main 
 reservoir to equalize at a certain stated pressure than if it 
 is short, for a long brake pipe holds more air than a short 
 one. Then, again, if the brake pipe has considerable com- 
 pressed air left in it after setting the brake, it will equalize 
 at a higher point than if it is empty. This emphasizes the 
 fact that it will be hard work to release the brakes on a 
 long train if you exhaust all the air in making an ap- 
 plication. 
 
 Another place where equalization is important is on the 
 second application shortly after releasing brakes. It takes 
 time for the brake pipe and auxiliary pressures to equalize. 
 If you do not wait this proper time the auxiliary will not 
 have charged to standard pressure, and, of course, when 
 brake is set it will not reach as high a final pressure on 
 brake piston, which reduces the braking power. 
 
 Equalization between brake pipe and auxiliary on 
 making the reduction for a second application is very 
 important, because if brake pipe has a high pressure which 
 the auxiliary has not reached, the triple piston cannot 
 move till the brake pipe pressure has been drawn down a 
 
20 BRAKE OPERATION 
 
 trifle lower than the auxiliary. If one is 80 and the other 
 60; it means a reduction of 20 pounds before brake begins 
 to set, and about 20 more to set all brakes tight. This 
 affects the work of the brake on a short train more than 
 a long one. With a large main reservoir and a short train 
 it is easily done. 
 
 This defective handling of the brake is called "over- 
 charging the brake pipe," and can be avoided by returning 
 the brake valve to lap from full release as soon as the 
 brake pipe has had time to charge up its whole length, 
 which will move all triples to exhaust position and quickly 
 equalize the brake pipe and auxiliary pressures. When 
 these pressures are equalized, a very slight reduction in 
 the brake pipe pressure sets all the triples to work at once. 
 In stopping a short passenger train for baggage or at a 
 water plug, if the stop is being made too soon, go to a full 
 release for an instant to move all the triples to release, 
 then back to service application, making a service reduc- 
 tion of 6 or 8 pounds which will probably set the triples 
 before all the air has passed out of brake cylinders, and 
 in addition to holding the brake set at a low pressure will 
 have all of them ready for a further application at an 
 instant's notice so that you can stop at the exact spot 
 required. Never try this with a long train of any kind at 
 slow- speed, as you are liable to break the train in two. 
 
 A few hints on getting ready to make a good stop and 
 knowing whether you can depend on the brake to operate 
 properly may be of service here. 
 
 When operating the brake valve, you should listen to 
 the sound of the brake pipe air discharging from it, 
 because the sound tells how many cars you have in your 
 train with brake pipe connected and how the valve is 
 doing its work, just as the exhaust of the locomotive tells 
 whether the valve motion is in order ; any unusual sound 
 notifies you that something is wrong. 
 
 When you make a test of the train brake before start- 
 ing out, make the same kind of an application as when 
 stopping at a station, by successive reductions; a 5 to 7 
 
BRAKE OPERATION 21 
 
 pound reduction for the first one, lighter ones afterwards; 
 then you will know how -the brake will work when making 
 station stops. It should be full application to get the full 
 piston travel. 
 
 Never make an emergency application when testing 
 brakes unless specially called for, and then not till after 
 the first test has been finished. 
 
 If the brake leverage on the train is adjusted for 70 
 pounds train pressure, it is not safe to carry either more or 
 less. If you carry less, you cannot stop quickly when you 
 have to; if you carry more and skid the wheels, you will 
 slide by and will spoil a lot of wheels. We will speak of 
 this matter of leverage later on in connection with the 
 High Speed Brake and L Triple. 
 
 Have your air gage properly placed and well lighted, 
 so that it can be seen without taking your eyes too far off 
 the track and signals. Consult it often till you learn the 
 air brake business. If it does not register correctly or 
 sticks when the pressure is changing, call the attention of 
 the proper party to it. 
 
 It pays to inspect and test your engine equipment care- 
 fully before leaving the engine house; it may save you a 
 failure on the road. 
 
 Drain the main reservoir daily; the distributing valve 
 and the tender triple should be drained regularly in cold 
 weather. It is a good plan to open the cocks at rear of 
 tender and blow out the train pipes for both brake and 
 signal line before coupling to the train. 
 
 Too much oil used in the air end of the pump does 
 more harm than not enough, as it chokes up all the small 
 openings in the engine equipment. The piston rod pack- 
 ing needs more oil than the air piston; the air valves do 
 not need any. Use good valve oil always. 
 
 WHEN OPERATING THE AUTOMATIC BRAKE 
 REMEMBER 
 
 That the compressed air stored in the main reservoir is 
 
22 BRAKE OPERATIONS 
 
 used to charge up the brake pipe and auxiliary reservoirs, 
 and that it is used to release the .brake. Do not have any 
 water in any reservoir, as it takes up the room needed 
 for air. 
 
 That the compressed air stored in auxiliary reservoir 
 is used to set the brake. There is an independent supply 
 for each brake. Keep a full supply in each auxiliary. 
 
 That the brake is set by any reduction of pressure in 
 the brake pipe, no matter how it is made, if it is sufficient 
 to move the triple piston and valve. 
 
 That the brake pipe pressure must be reduced 5 to 7 
 pounds at first application, or brake pistons will not travel 
 over leakage grooves, allowing brake to leak off. 
 
 That the brake pipe pressure must be raised above the 
 auxiliary pressure, or the auxiliary pressure reduced by 
 bleeding, before the brake will release. 
 
 That you cannot recharge an auxiliary reservoir until 
 the exhaust port in triple is wide open, unless air leaks 
 past triple piston, as the feed port does not open until 
 after the exhaust port is open. 
 
 That a second application after release does not set the 
 brake as tight as the first full application, unless the 
 auxiliaries have had time to recharge to standard pressure. 
 This takes from 25 to 45 seconds. 
 
 That the small reservoir attached to brake valve is put 
 there to give a larger supply of air for the preliminary 
 exhaust of brake valve so you can make a gradual re- 
 duction. 
 
 That if your driver brake does not work quickly and 
 hold well with service application, in ninety-nine times out 
 of a hundred it is on account of a leak. 
 
 That the distributing valve used with the locomotive 
 brake must be kept clean and all pipe joints tight if you 
 expect to get good service from it. 
 
 That the position of the straight air brake valve and 
 the independent brake valve has all to do with the applica- 
 tion and release by the automatic brake valve of the 
 locomotive brake. 
 
DEFINITIONS 23 
 
 That in all these questions and answers it is under- 
 stood unless otherwise stated, that 70 pounds is the stand- 
 ard brake pipe and auxiliary pressure; 90 pounds main 
 reservoir pressure; and 8 inches the standard piston travel 
 for all passenger, freight and tender brake pistons. The 
 brake piston travels an inch or more farther when train is 
 running than with a standing test, so travel should be 
 adjusted to less than 8 inches. 
 
 And lastly, we will, define some of the terms which are 
 used to shorten the explanations you may hear. 
 
 A partial application means that the brake is set with 
 part of its full force; the brake cylinder pressure has not 
 equalized with the auxiliary reservoir pressure. 
 
 A full application means that the brake cylinder press- 
 ure has equalized with the auxiliary pressure, and has, 
 therefore, got the full pressure that can be obtained from 
 the air stored in the auxiliary. Be sure to distinguish 
 between a reduction and an application when telling any 
 one how the brake worked. A reduction is allowing air 
 to pass out of the train pipe whether the brake sets full 
 or partially. No matter how many reductions of brake 
 pipe pressure you make, it is only one application till it is 
 released. You can reduce the brake pipe pressure a few 
 pounds at a time and make eight or ten successive reduc- 
 tions, but it is only one application if it has not been 
 released. ' 
 
 A graduated or service application means a gradual 
 reduction of brake pipe pressure which sets the brake 
 slowly. In a graduated application it is not expected that 
 the quick action parts of any triple valve will operate. 
 
 An emergency application means a sudden and heavy 
 enough reduction of brake pipe pressure to set the brake 
 with full force at the first movement of the triple valve. 
 With this application the quick action part of the triple 
 valve operates, so that air from the brake pipe passes into 
 the brake cylinder and equalizes, after which the auxiliary 
 and cylinder pressures also equalize. 
 
THE 8 INCH AIR PUMP 
 
 The sectional view of this pump shows the steam and 
 air pistons 10 and 11 and all the steam valves in their 
 positions when the steam piston is making its stroke 
 upward. 
 
 The live steam comes from the boiler through the 
 governor and passage m into the chamber between the 
 heads of the main steam valve /. It also goes into port h 
 and through a passage in the wall of the steam cylinder 
 and in the top head, which is not shown as this port is 
 in the section cut away. This passage from h leads live 
 steam constantly into the steam chest e of the reversing 
 valve 16; it can pass through port a into the cylinder 
 and over the reversing piston 23, pushing it down; for 
 the combined area of the piston 23 and the small one 7 
 is greater that that of the top one 7. This opens the 
 steam port in the bushing 26; steam then passes under 
 steam piston 10. 
 
 At the same time the exhaust ports in bushing 25 are 
 open so any steam in the top end of the cylinder escapes 
 at y through f and g to the exhaust pipe. This moves the 
 steam piston up, bringing up the air piston 11. As the air 
 piston moves up, any air above it escapes through port p 
 by raising discharge valve 30 and passes into the main 
 reservoir. At the same time the lower end of the air 
 cylinder is filled with air from the atmosphere; when the 
 piston 11 raises, a partial vacuum is formed under it and 
 the pressure of the outside air forces up inlet valve 33 and 
 air passes into cylinder. On the arrival of the piston at 
 the top of its stroke, both these air valves, 30 and 33, drop 
 into their seats, remaining there during the return or 
 down stroke. The other set of air valves open on the 
 down stroke, 31 to admit air above the piston 32 to dis- 
 charge air from the lower end of the air cylinder to the 
 main reservoir. 
 
26 THE AIR PUMP 
 
 When the steam piston reaches the top of its stroke, 
 the reversing plate 18 strikes the shoulder n of the revers- 
 ing rod 17, moving it up; this in turn moves the reversing 
 valve 16 up also. Reversing valve 16 being moved up in 
 chamber e covers port a so live steam can no longer pass 
 on top of reversing piston 23 ; ports b and c are connected 
 by the cavity in valve 16 so that the steam in cavity d over 
 piston 23 exhausts through c and balances the pressure 
 on each side of piston 23. The top piston of main steam 
 valve 7, which has live steam under it, being larger than 
 the bottom one and piston 23 being balanced, the main 
 steam valve 7 is raised up, also moving up 23\ this move- 
 ment of 7 opens the upper steam ports and the lower 
 exhaust ports so that live steam pushes the piston 10 
 down to the bottom of the cylinder. When the piston 
 reaches the bottom of the stroke, the reversing plate 18 
 catches on the button x at the bottom end of reversing 
 rod 17 and moves the reversing valve back to the position 
 shown in the cut; the live steam then moves the piston 
 valves 23 and 7 to the positions shown there, and the 
 pump is ready for the up stroke. 
 
 The first sectional view of the 9^-inch pump is shown 
 with the main piston 65 and all the valves in the steam 
 end as they stand when the pump is making the upward 
 stroke. The live steam which comes up through passage 
 a at the back of the pump into steam chest A is always on 
 top of the main slide valve 83. This valve is shown at the 
 right hand end of its stroke, in which position it uncovers 
 port b so steam can pass down to the bottom end of steam 
 cylinder under the piston 65 and push it upward. At the 
 same time the exhaust cavity of this slide valve 83 con- 
 nects the port c, which opens into the top end of the steam 
 cylinder, with exhaust port d, which passes down around 
 the back of cylinder to the exhaust pipe; the steam above 
 the piston can then pass into the exhaust. This slide valve 
 83 is moved by the differential piston valve 76, with the 
 large piston 77 on one end and the small piston 79 on the 
 other. Chamber E is always connected to the exhaust 
 
I3|[_ 'LV-^ AIR 
 
 ■~-^T| /DISCHARGE 
 
 % ~t^£*8 
 
28 THE 9^-INCH AIR PUMP 
 
 passage through port t in the side of the main valve bush- 
 ing 75 so that this piston has live steam on the steam chest 
 side and the exhaust on the other at all times. The large 
 piston 77 on this valve 76 has live steam on the steam 
 chest side and the office of the reversing valve 72 is to con- 
 nect the chamber D at the outside end of 77 with the live 
 steam or with the exhaust as may be required to move 76 
 back and forth. When D is connected with the exhaust 
 both outside ends of the piston valve 76 have no pressure 
 on them, the live steam between the heads moves 77, 
 which has the greatest area, away from the live steam 
 pressure towards the right. When the main steam piston 
 63 approaches the top of its stroke the reversing plate 69 
 strikes the shoulder / of the reversing rod 71 which is 
 moved up carrying the reversing valve 72 up ; this admits 
 steam into port g } it passes along the side of the bushing 
 through the port shown into chamber D at the outside of 
 piston 77, which having live steam on both sides of it is 
 balanced. Piston 79 has live steam inside and exhaust 
 outside, so it moves away from the live steam drawing the 
 main slide valve 83 with it. This movement uncovers port 
 c, live steam passes down on top of the piston 65, the 
 exhaust cavity of 83 connects port b and exhaust port d 
 together and the steam from bottom end of cylinder can 
 pass up through passage or port b to the exhaust pipe. 
 Steam piston 65 will then make the down stroke. The 
 position of all the valves and pistons while the down 
 stroke is being made is shown on next page. When close 
 to the bottom end of the stroke, the reversing plate 69 
 catches the button x on the bottom end of reversing rod 
 71, pulls this rod down and with it reversing valve 72, and 
 connects chamber D with the exhaust through ports f and 
 h in the side of bushing 75. As soon as the pressure is 
 relieved, live steam moves piston 77 to the right, drawing 
 the main slide valve 83 with it; all steam valves are then 
 in the position shown on page 27, and the pump begins the 
 upward stroke. The main valve 7 of the 8-inch pump has 
 live steam between its two heads or pistons at the same 
 
AIR > 
 DISCHARGE 
 
 104 j 9 i±2 
 
30 AIR PUMP CAPACITY 
 
 time and this tends to force the main valve up. Piston 23 
 is used to overcome the advantage the large piston 7 has 
 and force it down for the up stroke of the piston 10. With 
 the 9 ^2-inch pump the differential piston 76 is moved by 
 changing the pressure on the outside of piston 77; this is 
 done by the reversing valve 72. The angling hole in cap 
 nuts 20 and 74 serves the same purpose in both pumps — to 
 balance the pressure on both ends of the reversing rods ; — 
 this opening connects with the top end of steam cylinder, 
 down past the reversing valve bushing. The reversing 
 valve 72 in the 9^-inch pump performs the same office as 
 valve 16 in the 8-inch pump, but the reversing valve 16 
 admits steam over the top of 16 through port a to piston 
 23, while valve 72 admits steam under the bottom end 
 through port g to piston 77. In both pumps the reversing 
 rods work the same and have the same class of troubles. 
 The arrangement of the steam valves in the 9^-inch pump 
 is much superior to that of the 8-inch in every way, and in 
 addition they are all located in the top head 60. In case 
 the steam valves get out of order, by changing the steam 
 head 60 with its reversing rod 71, we get a good pump 
 again. 
 
 The air valves in the 9^2-inch pump are all of one size 
 and have the same lift — three thirty-seconds of an inch; 
 when new they are interchangeable with each other. The 
 air valve cages 88 are also interchangeable. As these air 
 valves act the same as those of the 8-inch pump when the 
 pump is working, an explanation is not necessary. 
 
 This pump is 9^ inches bore and 10 inches stroke; with 
 140 pounds of steam it should fill a main reservoir 26 Z A 
 inches in diameter by 34 inches long, having a capacity of 
 about 15,000 cubic inches from up to 70 pounds in 38 
 seconds, or from 20 to 70 pounds in 27 seconds. You can 
 determine whether a 9^-inch pump is in good order by 
 testing it and noting whether it can do this work. 
 
 An 8-inch pump should pump this amount of air from 
 to 70 pounds in 68 seconds, and from 20 to 70 pounds in 
 about 50 seconds, using steam at 140 pounds. 
 
AIR PUMP CAPACITY 31 
 
 The 11-inch pump is much the same in construction as 
 the 9^2-inch pump. It is 11 inches bore and 12 inches 
 stroke. The air valves are much larger, but have the same 
 lift, three thirty-seconds of an inch. Its operation is the 
 same, so the explanation for one pump will do for the 
 other. The capacity is much greater, as 100 strokes of the 
 11-inch pump will compress 48 cubic feet of free air, while 
 100 strokes of the 9^-inch pump will compress 36 cubLc 
 feet. When working at full capacity the 11-inch pump 
 will compress 58 cubic feet of free air per minute and the 
 9 ^2-inch pump 38 cubic feet. 
 
 The steam end of the pump is usually oiled by a sight 
 feed cup, either a part of the engine cylinder cup or a 
 small independent one. The air cylinder can be satis- 
 factorily oiled by an attachment to the oil tank of the 
 regular cylinder cup — see illustration and description on 
 inside of front cover. This sight feed device is a down 
 drop through air instead of an up drop through water. 
 When operated, the regulating valve at the top is opened 
 to feed a few drops at a time, not more than ten, and at 
 such intervals as in the judgment of the engineer is 
 required. It is not intended for a continuous feed, that 
 is liable to give too much, oil, this is as bad as not 
 enough. 
 
MAIN VALVE BUSHING 
 
 This cut shows 
 the position of re- 
 versing valve 72 
 when pump i s 
 making the up 
 stroke. 
 
 Port g in main 
 valve bushing is 
 for live steam to 
 piston 77: his port 
 for exhaust from 
 this piston ; ./"con- 
 nects with exhaust 
 portrf. 
 
 This cut shows 
 the position of re- 
 versing valve 72 
 when pump is 
 making the down 
 : H stroke. 
 
 See page 28. 
 
DEFECTS OF THE AIR PUMP 33 
 
 DEFECTS OF THE AIR PUMP 
 
 Many of the break-downs and defects of the air pump 
 can not be remedied when away from the "shop, some of 
 them can ; it is important to locate the nature of the de- 
 fect at once to know if it can be fixed then and there, or if 
 another air brake engine will be needed to handle the 
 train as well as to be able to properly report the defect 
 on the work book. 
 
 In the case of any disability or break down of the 
 steam end the pump usually stops altogether. If the air 
 end is out of order it will not make any air or at the best 
 will work irregularly. We will first take up the disabilities 
 which will make the 8-inch pump stop altogether. First 
 see that a full supply of steam goes to the pump; if it 
 does not the trouble may be in the governor. 
 
 Leaky gaskets in the steam head or leaks past the 
 bushings from one port to another will let the live steam 
 blow into the exhaust so there is not enough pressure to 
 reverse the pump. In such cases you can hear the blow, 
 the pump is pretty certain to stop at the bottom end of the 
 stroke and stay there. If the copper gasket gets cracked 
 at the opening where steam goes through from port h into 
 the steam head the live steam can blow on one side into 
 the exhaust, on the other into the steam cylinder; this 
 leak does not always stop the pump, usually it does. If 
 anything works into this port h and stops it up so steam 
 can not pass through in sufficient volume to hold proper 
 pressure for the reversing piston it will stop. 
 
 Leaks past the bushings are not unusual; when once 
 they start, the steam soon finds a way to get to the exhaust 
 without doing its work. 
 
 When the packing rings and valves in the steam end 
 become worn the oil will blow into the exhaust before it 
 has oiled all the moving parts. This will leave reversing 
 piston 23 so dry that it will not move and reverse the 
 position of main steam valve 7. This is a case where 
 
34 AIR PUMP DEFECTS 
 
 increasing the feed of oil and jarring the steam head with 
 a block of wood will usually start the pump. 
 
 A piston rod broken where it joins piston 23 will act 
 much the same way; this rod has been known to get stuck 
 in the bottom hole in the bushing and hold the piston 
 down. The small hole starting in the side of this bushing 
 running down and to the side of this piston rod is to oil 
 this rod; if it gets stopped up it should be opened. Some- 
 times the top of reversing piston 23 will wear to a steam 
 tight fit against the cap nut 21; this keeps the steam off 
 the top of piston 23, it can not then push it and main 
 steam valve 7 down. An examination of these surfaces, 
 and if necessary nicking the smooth surfaces so the steam 
 can get in, will remedy this. 
 
 When the reversing plate 18 gets loose, or the button x 
 on the reversing valve rod 17 breaks off, the pump will 
 reverse at the top end of its stroke, but not at the bottom 
 and will stop at the bottom end of its stroke. If the steam 
 is now shut off and the reversing valve allowed to settle 
 down by gravity when the steam is turned on, the pump 
 will make another double stroke and stop again. Taking 
 off the cap nut 20 and raising up the reversing rod will 
 show whether this is the trouble. In this case a spare rod 
 17 comes handy. If the plate 18 is loose the steam head 
 will have to come off to get at the plate. If one of the 
 nuts '58 holding the air piston on the piston rod works off, 
 or a piece of it breaks off — these nuts split sometimes — 
 and gets under the air piston so that it can not come clear 
 down to move the reversing rod and valve properly, that 
 will stop the pump. Take out the plug 59 in the bottom 
 head of the air cylinder or the entire head, and this trouble 
 can be located. If the nuts work off either end of main 
 steam valve 7 the pump is liable to stop at once. If the 
 stop pin 50 below the small piston 7 breaks off so the small 
 piston gets below the bushing 26 and sticks, the pump 
 will stop until this valve can be moved up. 
 
 Stoppage of the pump may be caused by an obstruc- 
 tion working into some of the small steam ports, closing 
 
AIR PUMP DEFECTS 35 
 
 them up, especially port h. Taking off the cap nut 21 
 after steam has been shut off and all the valves settled 
 down will locate this difficulty, as when all the passages 
 are free the steam will come out through port a over the 
 reversing piston 23. This same test will show whether 
 governor is open for steam but is not as reliable as break- 
 ing the joint between the governor and pump. We will 
 speak of the governor later on. 
 
 As the reversing rods, plates and valves are of the 
 same pattern in the il-inch, 8-inch and 9^4-inch pumps, 
 the failures of any of these parts affect all these pumps 
 alike. With this exception the steam end of the 9^2-inch 
 pump gives very little trouble if the joints and gaskets are 
 in good order. 
 
 Nearly all the blows of steam when the pump is at 
 work take place when the steam piston is making the 
 upward stroke. At that time the steam can blow past the 
 steam piston packing rings for when on the down stroke 
 the condensed water laying on top of this piston will pre- 
 vent much steam getting by the rings ; on the up stroke 
 there is nothing of the kind to hold the steam back. On 
 the up stroke live steam is on top of reversing piston 23 so 
 it can blow into the exhaust, on the down stroke it is ex- 
 haust on both sides. With the differential piston 76 of the 
 9^-inch exhaust steam is on both ends on up stroke. 
 
 A blow past these main valves of either pump is so 
 nearly like a blow past the steam piston that an examina- 
 tion is necessary to determine its location. A bad blow 
 coming all at once is a good indication of a broken 
 packing ring or a leak started through one of the copper 
 gaskets. 
 
 If the top end of the reversing rod is not a steam tight 
 fit in its cap nut in the 8-inch or 74 in the 9^-inch and 
 11-inch pump, steam will blow past there steadily on the up 
 stroke; passing through the small hole drilled obliquely 
 through the cap nut, then down past the reversing valve 
 bushing and into the upper end of steam cylinder which 
 on the up stroke is connected to the exhaust It can not 
 
36 LEAKY AIR VALVES 
 
 blow on the down stroke, as at that time live steam is in 
 the top end of the cylinder. Very few of these reversing 
 rods are steam tight in the cap nuts. This opening between 
 the steam space above the piston and top of cap nut is 
 necessary to balance the pressures on the reversing rod 
 so it will not move while the pump is making its stroke. 
 
 If the reversing rod gets bent so it catches on the 
 reversing plate or the button catches on the side of the 
 hole in the piston rod, the pump will reverse before it 
 completes its stroke. A pump that reverses too soon in its 
 stroke will pump very little air into the main reservoir. 
 
 A difficulty in the air end of the pump will usually give 
 notice at once by a quick stroke one way and a slow stroke 
 the other, which may be caused by several defects. If air 
 from main reservoir leaks past a discharge valve it will 
 fill that end of the cylinder with high pressure air so the 
 air piston will move away from it quickly and towards it 
 slowly. In such a case the inlet valve cannot lift — no air 
 will be drawn in at that end. If the inlet valve leaks an 
 examination will disclose it with the 8-inch pump. With 
 the 9*A and 11-inch pumps it is not so easy, as the air 
 passing out of one inlet valve will pass to the other and 
 give it the signs of a poor suction there. Improper lift of 
 valves will make a pump move faster one way than the 
 other. If the lift of an inlet valve is too small, that end of 
 the cylinder may not fill with air so the piston will not 
 meet with so much resistance in compressing the air. 
 If the lift of a delivery valve is too small the piston will 
 move very slowly at the last part of the stroke; it has to 
 wait for the compressed air to pass through the small 
 discharge opening. It will show more difference in 
 relative speed when the air pressure is low. 
 
 The lift of the receiving valves 31 and 33 of the 8-inch 
 pump should be one-eighth of an inch, of the discharge 
 valves 30 and 32 three thirty-seconds of an inch. This lift 
 is very soon changed by the wear of the valves and the 
 seats; too much lift of discharge valves will make the 
 pump pound, as well as wasting main reservoir air by 
 
AIR PUMP DEFECTS 37 
 
 allowing some of it to flow back into the cylinder before 
 the valves can seat. To test for a leak in the bottom 
 discharge valve, pump up full pressure, stop the pump, 
 take out the plug in the bottom head — air will blow T out 
 there steadily from a leak. To test for a leak in top dis- 
 charge valve leave this bottom plug out and open the oil 
 cup on top end of cylinder; see if air blows out there 
 steady; if so, it comes from top valve. You should have 
 both ends open as the air might leak past piston packing 
 and appear to come from the wrong end. 
 
 Leaky packing rings, leaky valves, choked air passages, 
 all tend to make the pump run hot. Running the pump 
 at too high a speed is generally the trouble in the first 
 instance. When once it has been very hot the packing 
 rings contract and do not fill the cylinder; the valve bush- 
 ings leak and the oil burns on the inside of passages and 
 make a bad matter worse. 
 
 The Westinghouse Company are now making a cross- 
 compound air pump in which the high pressure steam 
 piston operates the low pressure air piston; the steam 
 when exhausted from this cylinder then passes across to 
 the other end of the low pressure steam cylinder and 
 operates the low pressure steam piston and the high 
 pressure air piston. A diagrammatic view of this pump 
 is shown ; as by this means the steam and air passages can 
 be more clearly traced. The reversing rod 21 and valve 
 22 are operated by the reversing plate 18 at the end of the 
 stroke of the high pressure steam piston 7 in the same 
 manner as the 9 V 2 -inch pump. 
 
 The first design of this pump had a differential piston 
 and slide valve to open and close the steam and exhaust 
 ports for the steam cylinders ; very few of this pattern 
 are in service. A later design has a piston valve instead 
 of a differential piston and slide valve. This piston valve 
 consists of five pistons, a large one at one end and a small 
 one at the other that have the same duties as the differ- 
 ential pistons in the other pumps, between these two and 
 pistons are three intermediate pistons of the same size 
 
38 CROSS-COMPOUND AIR PUMP 
 
 that open and close communication between the ports 
 leading to and from the steam cylinders. 
 
 The same type of reversing valve is used, except that 
 the exhaust cavity is 'near the top, in the old one it is 
 near the bottom. 
 
 Steam from the boiler after passing the governor, 
 comes in at the side, passes through port a up and across 
 the steam head into ports b inside the large piston at 
 one end and inside the small piston at the other; the 
 diagrammatic view shows all these ports. Live steam also 
 passes in at port k around the reversing valve 22. 
 
 As the high pressure steam piston must make at least 
 one full stroke before any steam can pass into the low 
 pressure cylinder, in this explanation we will consider 
 that high pressure piston 7 has made its first up stroke 
 moved the reversing valve to its top position and opened 
 steam port n so live steam has passed into cylinder D 
 and forced piston valve 25 to the left as shown; E at the 
 small end is always in connection with the exhaust e 
 through port o. Live steam now flows through port c on 
 top of piston 7 forcing it down. Steam under piston 7 
 that moved it up in making the previous stroke can now 
 pass through port g from the bottom of this cylinder up 
 into cavity i between the first and second intermediate 
 pistons, thence down through port / into the bottom of 
 the low pressure cylinder under piston 8, forcing it up; 
 any steam above this piston can escape through port d 
 and cavity h between the second and third intermediate 
 pistons into exhaust port e and the atmosphere. 
 
 When piston 7 is about to complete its down stroke 
 it moves the reversing rod and valve down also, this closes 
 port n and connects exhaust port m from cylinder D with 
 the exhaust port / leading to e so the steam in D escapes 
 to the exhaust, live steam pressure in cavity b at once 
 moves piston 25 to the right connecting ports c and d 
 through cavity h, the steam above piston 7 now passes in 
 above piston 8, live steam from b flows through port g 
 into the bottom end of high pressure cylinder and piston 
 
STEAM ££s 
 [EXHAUST. 
 
 AIR DISCHARGE. 
 
 40 38 
 
 Diagram of the Cross Compound Pump, Down 
 Stroke, High-Pressure- Steam Side. 
 
40 CROSS-COMPOUND AIR PUMP 
 
 7 makes the up stroke, piston 8 makes the corresponding 
 down stroke, the steam below it escaping to the exhaust 
 through port -f and cavity i to c. Port s is a balancing 
 port to equalize the pressure on the top and bottom of the 
 reversing rod 21. 
 
 The low pressure steam cylinder has three by-pass 
 grooves in it at each end that are open just as the low 
 pressure piston completes its full stroke and allow steam 
 to pass around the piston from the pressure side to the 
 exhaust side of piston 8. The steam pistons move at the 
 same time, but in opposite directions, the high pressure 
 piston moves the reversing rod and valve so this piston 
 must make a complete stroke each time to operate the 
 piston valve 25 and change the course of the live and 
 exhaust steam. 
 
 The course of the air through the air cylinders and 
 valves from the atmosphere to the low pressure cylinder, 
 then across into the high pressure air cylinder is shown 
 by the small arrows pointing in the direction the air is 
 flowing. When the low pressure air piston 9 made its 
 up stroke any air above it was forced out past the upper 
 intermediate valves 39 behind the moving high pressure 
 piston 10 and air below piston 10 passes out by discharge 
 valve 42 to the main reservoir. In the diagrammatic view 
 low pressure air piston 9 is shown making the down 
 stroke, air from the atmosphere is flowing in at the upper 
 air inlet thence by the inlet valves 37 and port s, and fill- 
 ing the air cylinder behind the moving piston 9, inter- 
 mediate valves 39 prevent any air coming back from the 
 high pressure air cylinder. The air below piston 9 is 
 now compressed till it will pass out through port t past 
 intermediate valves 40 into the high pressure cylinder 
 below piston 10 that is making its up stroke; the air above 
 it is compressed till it exceeds the main reservoir pressure 
 and raises discharge valve 41, passing out through w to 
 the main reservoir. 
 
 The inlet and intermediate air valves are double, as 
 39 and 40 show, 37 and 38 being set the other way across 
 
PUMP GOVERNOR 41 
 
 the pump; the sectional view shows only one of the pair. 
 During the stroke of the pistons the intermediate pressure 
 being that between the low and high pressure air pistons 
 reaches about 40 pounds. 
 
 The high pressure steam piston 7 has a diameter of 
 §y 2 inches, low pressure steam piston 8 is 14^ inches ; 
 all pistons have a stroke of 12 inches. The low pressure 
 air piston is 14^ inches and the high pressure air piston 
 9 inches in diameter. 
 
 The capacity of this pump is 131 cubic feet of free 
 air per minute, as against 58 for the 11-inch pump work- 
 ing under the same condition. 
 
 THE PUMP GOVERNOR 
 
 The duty of the pump governor is to shut off the 
 steam from the air pump when the air pressure has reached 
 the standard desired. Where only one pressure is to be 
 controlled, the single governor is used ; if more than one 
 pressure, the duplex governor is used. The steam valve 
 and its air piston are the same with both the duplex and 
 single governors, but one or two air tops are used, accord- 
 ing to the number of air pressures controlled. 
 
 It is located close to the pump on the steam pipe, at 
 the union connection 70 the air that operates the governor 
 enters, and is under the diaphram 67. This diaphram is 
 held down by the regulating spring 66, which can be 
 adjusted by the regulating nut 65. 
 
 We w T ill suppose that the spring 66 has been adjusted 
 to hold the diaphram down against the air pressure of 90 
 pounds and no more. When the air pressure exceeds 90 
 pounds the, diaphram will be raised against the resistance 
 of the spring; this will raise the air valve, air will flow in 
 on top of the air piston 53 and' force it down, moving 
 steam valve down to its seat and closing the steam sup- 
 ply to the pump, which will stop it. 
 
 As soon as the air pressure falls so the regulating 
 spring 66 can move the diaphram down and close the air 
 
42 
 
 PUMP GOVERNOR 
 
 PUMP GOVERNOR 
 
 * DETArLS. 
 
 valve the air pressure above the piston drops, and the 
 steam valve is opened allowing the pump to take steam 
 again. With the duplex governor the regulating spring of 
 one air top can be adjusted for one pressure and the other 
 spring for another pressure. Thus the pressure carried 
 depends on which side of the governor is in operation. 
 There are several causes which will prevent the gov- 
 ernor from shutting off the steam from the pump when the 
 maximum air pressure is obtained. If the regulating 
 
 spring is screwed down too 
 tight it will not allow the 
 diaphram to raise and lift 
 the air valve off its seat. If 
 too much oil is used in air 
 end of pump the air valve 
 gets gummed up where it 
 rests on its seat so air can 
 not get through after air 
 valve raises. This is the 
 most common cause of the 
 pressure getting higher 
 than the governor is set 
 for. To cure this trouble 
 take out diaphram and 
 clean off air valve and its 
 seat so air can get through 
 freely when air valve raises- 
 If the air leaks past piston 
 as fast as it comes through 
 air valve, the piston will 
 not be moved down as 
 there will be no pressure 
 above piston. Putting in a 
 tight packing ring cures 
 this unless the cylinder is 
 worn out of true. If the governor piston sticks so air 
 pressure will not force it down, steam will not be shut 
 off. If the waste pipe in the side of steam end of gov- 
 
 50. Steam- Valve Body 
 
 51. Steam Valve. 
 
 52. Cylinder Cap. 
 
 53. Governor Piston 
 04. Piston Packing Ring.65- 
 f>5. Governor-Piston Nut. 
 36. . Governor-Piston Spring 1 
 57. Strain - Valve Cylinder 
 
 6ir- Diaphragm Body. 
 
 63. Spwng Box. 
 
 61 Cap Nut. 
 
 65. Regulating Nut. 
 
 66. Regulating Spring. 
 ty7. Diaphragm complete; 
 
 *£$, Diaphragm Ring. 
 
PUMP GOVERNOR 43 
 
 ernor is stopped up so steam or air is confined below 
 piston, the governor will not shut off at any pressure. 
 This waste pipe may be smashed out flat so nothing can 
 pass through it, in cold weather it will freeze solid full 
 at the bottom end which will keep the air piston held up. 
 If anything gets in over diaphram so it cannot raise, that 
 will hold air valve shut so air cannot get on piston to shut 
 off steam valve. If valves and seats are kept clean, and 
 all parts allowed to move as they should, governor will 
 work accurately. In case the governor shuts off the steam 
 with less than the standard pressure you are likely to find 
 there is dirt or a scale holding the air valve off its seat 
 so air can get through on top of piston steadily, in which 
 case the governor will shut off steam as soon as air 
 pressure on the top of governor piston will more than 
 balance steam pressure on steam valve. If this air valve 
 seat is injured so it leaks, or a new valve has been put in 
 that is too short to make a good joint, a very low air 
 pressure, less than forty pounds, will shut off the steam. 
 A broken regulating spring will also do this. 
 
 Sometimes the pump will not start up soon after the 
 air pressure in the governor has been reduced below that 
 the governor diaphram is set at. This is because when the 
 air valve closes, the air is shut up in cylinder over gov- 
 ernor piston and must leak out before piston can raise and 
 open steam valve. The old type of governor D-9 had this 
 trouble, but the new style of governor E-8 has a small 
 blow hole drilled in the side of 62, below air valve seat, 
 which lets enough air escape after standard pressure is 
 reached to keep pump running steadily. 
 
 To find if the trouble is in the governor when the 
 pump will not start, open both drip cocks in the 9^2-inch 
 or 11-inch pumps, or break the joint between the governor 
 and 8-inch pump; if live steam comes out freely the gov- 
 ernor is not at fault. In such a case shut off steam at the 
 boiler, wait a few seconds till steam is out of pump and 
 turn it on again, if the live steam blows out freely, the 
 trouble is in the pump. 
 
44 PUMP GOVERNOR 
 
 With the single top governor and a brake valve using a 
 feed valve to regulate the brake pipe pressure, main reser- 
 voir air is used to operate the governor, with some types 
 of brake valves like the old D-8 or the N. Y. brake valve 
 brake pipe pressure operates the governor. With the 
 duplex governor one side is usually piped to the main 
 reservoir direct, the other side, in some cases, uses brake 
 pipe air. With the high speed brake, one side is set for 
 90 pounds, the main reservoir pressure used with the 
 ordinary brake pipe pressure of 70 pounds ; the other side 
 for the higher pressure needed to release brakes, using 
 110 pounds. In such cases there is a stop cock in the 90 
 pound side air pipe, which is to be closed to cut out that 
 side when the higher pressure is used. The N. Y. brake 
 uses a triple governor. 
 
 There is also a method of piping which allows of two 
 main reservoir pressures being used, one on release and 
 running position of the F-6 brake valve and a higher one 
 with the valve on lap and application positions. The 90 
 pound side is piped to the port / in the 1892 model brake 
 valve at a point just above the figure 62 — see the cut of 
 this valve farther on. When the rotary is in full release 
 or running position, main reservoir air can come freely 
 into this port and operate the governor at a pressure of 
 90 pounds. During a brake application this port / is closed 
 by the rotary and the air pressure there soon equalizes 
 with the brake pipe. 
 
 The 90 pound side of the governor does not then con- 
 trol the pump and the high pressure side which is con- 
 nected directly to the main reservoir and adjusted for a 
 pressure higher than 90 pounds, usually 110 pounds, allows 
 the pump to run and raise the main reservoir pressure so 
 as to have a good stiff excess to release brakes. 
 
 There is also a method of piping the S F duplex gov- 
 ernor with the E. T. brake to control the amount of excess 
 pressure regardless of what the brake pipe pressure may 
 be. One side is piped to the main reservoir direct at 
 MR, and set 120 or 130 pounds, according to what the 
 
PUMP GOVERNOR 
 
 45 
 
 maximum main reservoir pressure is to be. The other 
 side has a light spring 27 over the diaphram that has the 
 proper tension to hold the diaphram 21 down for the 
 
 
 THE SF=4 PUMP GOVERNOR 
 
 excess desired. At A B V main reservoir air from the 
 brake valve comes in under the diaphram at d from the 
 automatic brake valve in full release, running and holding 
 positions. The position of the brake valve regulates the 
 flow of air to the excess pressure side. At FVP feed valve 
 air at the reduced pressure comes in above the diaphram, 
 and its pressure is added to that of the spring 27 so that 
 we have 70 pounds brake pipe plus that of the spring — 
 say 20 pounds — so that when the main reservoir air in d 
 
46 PUMP GOVERNOR 
 
 can overbalance the presure of 70-^20 above the diaphram, 
 the diaphram will raise the pin valve and admit air over 
 the governor piston and close the steam valve 5, This 
 will operate the same at any other brake pipe pressure; 
 so there will be the same excess, depending on the adjust- 
 ment of the spring 27. Air passes in at ABV only in 
 release, running and holding positions of the type H 
 brake valve. When the brake valve is moved to lap or 
 beyond the air is cut off from under the diaphram at d 
 and the pressure at a and spring 19 control the pump. 
 A peculiarity of operation of this governor is that when 
 charging up a long train through the brake valve in run- 
 ning position, if there is more than 20 pounds difference 
 between main reservoir and brake pipe pressures the gov- 
 ernor will stop the pump. In such a case put the brake 
 valve in full release and the pump will soon start. 
 
AIR BRAKE CATECHISM 
 
 1. Q. What are the essential parts of the automatic 
 brake and what service does each part perform? 
 
 A. The air pump, the main reservoir, the engineer's, 
 brake valves, automatic, independent and straight air, the 
 brake pipe with its hose, couplings, and angle cocks, the 
 auxiliary reservoir, the triple valve, the brake cylinder, 
 the gage and the pump governor. The air pump com- 
 presses the air for setting and releasing the brake; the 
 main reservoir is used to store a supply of air for charging 
 the brake pipe and auxiliary reservoirs when empty, as well 
 as to hold the supply for increasing the brake pipe pressure 
 when the brake is to be released and to charge the brake 
 pipe and auxiliaries ready for the next application; the 
 automatic brake valve governs the passage of the air from 
 the main reservoir to the brake pipe, from the brake pipe 
 to the atmosphere, or stops the flow of air through it in 
 any direction. The brake can be set gradually or full on, 
 held set or released, when this valve is properly handled 
 by the engineer. The feed valve controls the supply of air 
 to the brake pipe in running position of brake valve and 
 regulates its pressure; the straight air brake valve passes 
 main reservoir air, reduced to 45 pounds, to and from the 
 brake cylinders direct. The brake pipe, with its hose and 
 couplings, extends from the brake valve, to the last air 
 brake car, and supplies each auxiliary reservoir with air 
 for setting the brake. It is also a means of communication 
 from the engineer's brake valve to each triple valve, and 
 from one triple valve to another in the quick action or 
 emergency application. 
 
 Each brake has an auxiliary reservoir in which the air 
 is stored for operating it to set. The triple valve consists 
 of three separate valves and is connected to the brake 
 pipe, auxiliary and brake cylinder; it is used to control 
 the charging of the auxiliary with air and regulate the time 
 
48 INSPECTION AT ENGINE HOUSE 
 
 in which this is done, to open a valve to admit air from 
 auxiliary to brake cylinder to set the brake, or by another 
 movement to close this valve and open the exhaust port 
 so air can get out of brake cylinder to the atmosphere and 
 release the brake. Thus the functions of the triple valve 
 are three-fold, to charge the auxiliary, set the brake and 
 release it. The triple valve is operated by a variation of 
 pressures between the brake pipe and auxiliary; this varia- 
 tion is controlled by the brake valve. The brake cylinder, 
 with its piston connected to the brake levers, beams and 
 shoes, sets the brake when the triple valve lets air into it. 
 The gage shows with the red hand main reservoir press- 
 ure, with black hand pressure in the brake valve above 
 the equalizing piston and in brake valve reservoir ; when 
 brake valve is in full release, running, or holding position 
 it also shows brake pipe pressure. The pump governor 
 is located in the steam pipe to pump ; it is operated by air 
 pressure and shuts off steam from the pump when the air 
 pressure reaches the standard amount carried. 
 
 In addition to these essential parts there is the pressure 
 retaining valve that is attached to the exhaust outlet of 
 the triple valve and controls the flow of air away from the 
 brake cylinder when the triple valve is in release position; 
 the conductor's valve that when opened reduces the brake 
 pipe pressure and applies the brake, the release valve or 
 rjleeder connected to the auxiliary reservoir used to reduce 
 the auxiliary pressure and release a single brake. A 
 separate valve and its reservoir called the distributing 
 valve is used on locomotives and performs the duties of 
 the triple valve by applying and releasing the locomotive 
 brake. A high speed reducing valve is used on coaches. 
 
 2. Q. What are the duties of an engineer as to his air 
 brake equipment when leaving the roundhouse? 
 
 A. To start his pump slowly and increase its speed 
 after 15 or 20 pounds of air have picked up ; to be sure 
 that pump is in good order and will pump a full supply 
 of air promptly; to know that governor shuts off the 
 pump when the proper pressure is reached and not before, 
 
TESTING FOR LEAKS 4$ 
 
 and allows it to start promptly; to see that lubricator has 
 oil enough in it for the trip ; to know that there is no 
 water in the main reservoir, drain cup, triple valves, 
 auxiliary reservoirs or distributing valve, to test all joints 
 in piping, also brake valve and triple valves for leaks, 
 and have leaks made tight; to see that tender and driver 
 brake pistons have the proper travel and do not leak off" 
 when set; to test the air signal if one is used. 
 
 3. Q. Why must the pump be started slowly, oil used 
 cautiously, triple valves, reservoirs and tender strainers be 
 drained, and how often? 
 
 A. The pump must be started slowly to allow the 
 condensed water to get out of steam end, and run slowly 
 till the air pressure rises, or the piston will strike the 
 heads of air cylinder. The triple valves, reservoirs and 
 strainers, or drain cups, should be drained every day in 
 cold weather, once a week in warm weather. Oil should 
 be used sparingly in air end of pump. It should never be 
 put in through the air inlets of the pump, as it soon 
 collects dirt and chokes up the air passages, which helps 
 to make the pump run hot. 
 
 4. Q. How do you test for leaks in the engine equip- 
 ment? 
 
 A. When full pressure is obtained — 70 in brake pipe, 
 90 in main reservoir — shut off pump, place valve on lap ; 
 if red hand drops and black hand is stationary, it is a sign 
 of a leak somewhere in main reservoir line, which begins 
 at valves in pump and ends at brake valve. It may be in 
 joints of piping, in main reservoir drip plug, in the air 
 signal line, in valves of pump or brake valve. If there is 
 an air sander or air bell ringer on the engine their valves 
 are liable to leak. If main reservoir pressure falls rapidly 
 when you are sure it is not going into brake pipe under 
 rotary, examine each of the places mentioned. With the 
 use of the cut-out cock under brake valve a leak under 
 rotary is soon detected. Set the brake full on, place the 
 valve on lap, shut the cut-out cock ; if rotary leaks into 
 brake pipe the black hand will soon show same pressure- 
 
50 TESTING FOR LEAKS 
 
 red one does ; if rotary is tight and air leaks out of brake 
 pipe the black hand will drop. With a leak in brake pipe 
 of engine or tender and cut-out cock shut, the brake will 
 set with valve on lap, and cut-out cock open the black hand 
 will fall slowly. For a leak in signal line shut the cut- 
 out cock next the reducing valve; a leak here will make 
 the whistle blow. Using a torch or putting soapsuds on 
 a suspected leak will generally locate air blowing out 
 there. 
 
 5. Q. Why must there be no leaks in your brake pipe 
 or any other part of your air brake supply? 
 
 A. If brake pipe leaks, brake will continue to set 
 tighter when brake valve is put on lap, and stop the train 
 oefore you want it to, so that it is necessary to let it off 
 and make another application for an ordinary stop. If 
 cars are cut off from engine, they must be bled at once if 
 their brake pipe or angle cocks leak. Brake pipes some- 
 times get worn through where they rest or rub against 
 something, so they are tight when standing still and leak 
 when moving or shaken around. This leak sets the brake 
 when train is in motion, and no leak can be heard when 
 standing still. Jar the pipes a little when inspecting the 
 engine to locate this leak. Sometimes the brake levers 
 strike the end of plug in stop cock and push it in so it will 
 leak when brake is applied. 
 
 6. Q. Why must all hose couplings be hung up prop- 
 erly when not in use? Why should they always be blown 
 out at rear of tender before uniting to other couplings? 
 What is the difference between an air brake and an air 
 -signal coupling? 
 
 A. So no dirt or foreign matter will get into the Open 
 coupling and work into the triple or brake valve or stop 
 xip strainers. So couplings and gaskets will not get injured 
 or broken dragging over rails and crossings. If blown 
 out each time, any water, sand or dirt in the tender piping 
 will be blown out. Air brake and air signal couplings are 
 of different sizes — made so purposely — so the brake line 
 •cannot be coupled to the signal line. The opening and lip 
 
TESTING FOR LEAKS 51 
 
 of the lock in brake coupling is much wider than the signal 
 coupling, so the brake coupling will not go into it. It is 
 the practice to paint the signal couplings red so they are 
 more easily distinguished when taking hold of them to 
 couple up. 
 
 7. Q. If main reservoir has water in it, how will it 
 affect the operation of the brake ? 
 
 A. The water in main reservoir reduces the supply of 
 air stored there in proportion to the amount of water con- 
 tained. The brake will set the same, but on a long train 
 will not release as readily, as there will not be enough air 
 stored to recharge the brake pipe quickly and you must 
 wait to have it pumped. The main reservoir should be 
 entirely clear of water, even if it is necessary to drain it 
 each trip, so as to get a prompt release and recharging 
 of train. 
 
 8. Q. How does this water get into the main reserv- 
 voir? 
 
 A. The air from the atmosphere before compression 
 contains more or less moisture in the shape of vapor. 
 After compression the air can not hold all this vapor as it 
 is compressed to a very much smaller volume, so nearly all 
 the vapor falls to the bottom of the main reservoir as solid 
 water as soon as the air cools of! to the normal tempera- 
 ture of the outside air. If the pump runs hot so the air 
 does not cool off in the main reservoir some of the water 
 will be found in the triple valves and drain cups. 
 
 9. Q. Of what use is the extra main reservoir press- 
 ure, and does the size of the reservoir have anything to 
 do with the amount of excess pressure you carry? 
 
 A. It recharges the brake pipe and forces the triple 
 pistons up into exhaust position quicker and surer, so 
 that all brakes release about the same instant; recharges 
 the auxiliary to full pressure in less time, ready for the 
 next application. With a large main reservoir there is a 
 greater volume of compressed air stored to draw from, 
 so a less number of pounds of excess pressure will do the 
 work than with a small reservoir. With a short train 
 
52 EXCESS PRESSURE 
 
 good work can be done with less excess than on a long 
 train. Excess pressure, as well as a large volume of 
 stored air, is needed on a long train, so the air will travel 
 from the engine to the rear car more quickly and release 
 the rear brakes at nearly the same instant the front ones 
 release; this will avoid many break-in-twos. Excess is 
 needed to release brakes and large volume to hold up the 
 pressure in brake pipe for recharging. The main reser- 
 voir should always be drained of water so it will be full 
 sized. 
 
 10. Q. Could it release the brakes with an empty 
 brake pipe as readily as when the pressure in the brake 
 pipe had been reduced only 20 or 25 pounds? Why? 
 
 A. No. When the air from the main reservoir ex- 
 pands into an empty brake pipe, it will not fill it up and 
 equalize at as high a pressure as when the brake pipe has 
 some compressed air left in it. For instance, the brake 
 pipe line of 25 freight cars holds 16,000 cubic inches, 
 about as many cubic inches of air as an ordinary main 
 reservoir. If this brake pipe is entirely empty and the 
 main reservoir has 90 pounds, it will equalize into twice 
 the space, and show half the pressure, or 45 pounds in 
 each. The brake would be set at 50 pounds; with that 
 pressure above triple piston, brakes could not release until 
 the pump had raised the pressure over five pounds. Now, 
 if the brake pipe line has been reduced 25 pounds, having 
 45 pounds still left in it, 90 in main reservoir and 45 in 
 brake pipe, would equalize at a little over 65, which would 
 raise triple pistons so brakes would release promptly. 
 
 11. Q. Would you run your pump as fast to recharge 
 an empty brake pipe as one with 45 or 50 pounds in it? 
 Is there any economy in retaining as much air as possible 
 and keeping the pump cool? 
 
 A. The pump would have to run faster to recharge an 
 empty brake pipe than one with 45 or 50 pounds in it. 
 When you empty the brake pipe of 25 cars it wastes as 
 much air as when you empty a small main reservoir; 
 smaller trains in proportion. This would make some 
 
EXCESS PRESSURE . 53 
 
 pumps hot to supply. Always save your air and keep the 
 pump cool, no matter what length of train you handle. 
 
 .12. Q. Please explain what excess pressure is. 
 
 A. Excess pressure is the difference between the main 
 reservoir and brake pipe pressures when the brake valve is 
 in running position so that the excess valve or the feed 
 \ alve can maintain a difference between the two press- 
 ures. In full release position these valves are cut out, 
 but the air can pass through an open port from the main 
 reservoir to the brake pipe and equalize, so in release 
 position there is no excess. If you carry excess you aim 
 to prevent this equalization and thus have a greater 
 amount of air in main reservoir to equalize into brake 
 pipe when necessary to release brakes. Of course it takes 
 more excess to promptly release all the brakes on a long 
 train than a short one. When releasing brake, it supplies 
 the brake pipe with a higher pressure than brake was first 
 set at; this makes the movement of all triples to release 
 position much quicker and surer. With a long train it is 
 absolutely necessary for this purpose. On a long train 
 excess is needed to force the air back through brake pipe 
 quickly and release brakes, with large volume to hold the 
 pressure up. It recharges the auxiliaries quicker, ready 
 for the next application of the brake. It charges empty 
 cars quicker that are taken on the train. When brakes 
 "creep on," they can be released at once by placing the 
 brake valve on full release for a second or two, just 
 long enough to raise the triple to exhaust position and 
 not long enough to charge the reservoirs to a higher press- 
 ure, then returning it to running position. 
 
 13. Q. Have we more than one pattern of equalizing 
 discharge brake valve? 
 
 A. Yes, we have several kinds of them in service, 
 called E-6, or F-6, D-8, H-5, and H-6, from the number 
 of the plate on which each is illustrated in the Westing- 
 house catalogue. The E-6 and F-6 valves are exactly 
 alike and are now known as the "1892 model'' or F-6 
 valve. Verv few of the D-8 valves are now in service. 
 
54 THE BRAKE VALVE 
 
 The H-5 and H-6 brake valves came next after the F-6 
 or 1892 model, and may be styled the 1906 model. 
 
 14. Q. Describe the principle on which it operates 
 and what difference there is between the patterns. 
 
 A. This brake valve has a rotary valve with various 
 ports and cavities in it by which the air can pass to and 
 from the various pipes and connections when the engineer 
 moves the rotary. It also has a piston in it called the 
 equalizing piston, with a brake pipe exhaust valve on the 
 bottom side of it which is designed to automatically re- 
 duce the brake pipe pressure. When brake valve is not 
 being operated this piston has an equal pressure on both 
 sides of it, so it remains stationary, holding brake pipe 
 exhaust valve closed. When it is used to set the brake, 
 the reduction of air pressure is not made by the engineer 
 direct from the brake pipe, but from the chamber in the 
 valve over the equalizing piston and the small reservoir 
 connected to the chamber. If the engineer wishes to re- 
 duce the brake pipe pressure any specified amount — say 
 seven pounds — he moves the rotary to service application 
 position. As the rotary passes lap position, the ports 
 which allow the air to pass from one part of the brake 
 valve to another are all closed. The main reservoir air 
 is held on top of the rotary as it is not used when the 
 brake is set, but only when releasing or charging the 
 brake pipe and auxiliary reservoirs. The air above the 
 equalizing piston and the brake valve reservoir being cut 
 off from all other air may be called brake valve air, it is 
 what operates the automatic part of the brake valve to 
 equalize the discharge of the brake pipe air, which is 
 below the piston. When the pressure of the brake valve 
 air is reduced by allowing some of it to escape from the 
 preliminary exhaust port, it does not reduce the brake 
 pipe air through the same opening; so the equalizing 
 piston having less pressure above it, raises up, opening 
 the brake pipe exhaust valve on the bottom of this piston 
 and air flows out of the brake pipe. As soon as the brake 
 valve air is reduced the amount the engineer wishes (and 
 
THE BRAKE VALVE 
 
 the amount of the reduction is shown with the black hand 
 of gage) he closes the preliminary exhaust port by a 
 movement of the rotary to lap. The pressure of the brake 
 valve air then remains stationary; while the brake pipe 
 air flows out through the brake pipe exhaust till it is 
 reduced a little lower than the brake valve air, which then 
 moves the piston down gradually and closes the brake pipe 
 
 EQUALIZING DISCHARGE VALVE 
 
 With Feed Valve Attachment. 
 
 1892 Model. 
 
 BRAKE l/ALVE 
 Running 
 Position 
 
 Plate D 5 Plate E'6. 
 and Plate F6. 
 
 These Brake l/a/res arc 
 q/ike irr construction 
 one/ ope rat/on. 
 
 Feeo Vtiyi 
 
 exhaust. It takes ■ longer to reduce pressure in a long 
 brake pipe than in a short one through the small brake 
 pipe exhaust port because of the greater volume of air in 
 
56 
 
 THE BRAKE VALVE 
 
 the long pipe, so the brake pipe exhaust is held open by 
 the brake pipe air till the pressure is reduced the whole 
 length, then closed automatically by the pressure of the 
 brake valve air. 
 
 Each of these valves uses a double hand gage and has 
 a small reservoir about 12 inches long connected to it by 
 
 lb Pump Coverkor 8k Gauge 
 -red hand- 
 MajN Reservo* Pressure 
 
 Feeu V*lve 
 
 a small pipe; this equalizing reservoir is used to supply 
 the cavity over equalizing piston with a larger volume of 
 air, so a more gradual reduction of pressure can be made 
 through the preliminary exhaust port from this cavity. 
 The later size of this reservoir is 14^2 inches long; it con- 
 tains a larger volume of air than those first used and 
 thus makes the reduction of brake valve air more gradual. 
 The F-6 has a reducing or feed valve attached, which 
 is set to regulate the brake pipe pressure at not over 70 
 pounds, at which pressure it closes and no more air can 
 pass to brake pipe from main reservoir till the brake pipe 
 pressure falls below what the feed valve is set at, when it 
 
THE FEED VALVE ."> i 
 
 opens again; with this valve the governor is piped to main 
 reservoir and set at ninety pounds. 
 
 Either of these valves when placed on emergencv 
 position opens a large port which lets the air from the 
 brake pipe direct to the atmosphere, making a sudden 
 reduction, which causes the brake to go on suddenly and 
 with full force. 
 
 15. Q. Describe the feed valve or brake pipe pressure 
 regulator. How many kinds are in use and what are the 
 differences in their operation? 
 
 A. There are three forms of the feed valve in general 
 use. The older one, called F-6. has a poppet valve, 63, 
 which is opened and closed by the movement of a piston, 
 74, which piston is moved in one direction, down, by the 
 pressure of the brake pipe air, and up by a regulating 
 spring, 68. 
 
 When the feed valve 63 is open, as shown in the illus- 
 tration, the main reservoir air which comes from the 
 brake valve when in running position, comes through f, 
 passes by valve 63 into cavity B, as shown by the arrow, 
 and out through port i into the brake pipe. Piston 74 is 
 held up against the brake pipe pressure in B by the regu- 
 lating spring 68, which is adjusted to hold the piston up 
 so the supply valve will not close till the pressure reaches 
 the standard amount, usually seventy pounds; at which 
 pressure the piston is moved down far enough to allow 
 valve 63 to close on its seat and shut off the supply of 
 main reservoir air passing into the brake pipe. 
 
 If from any cause the brake pipe pressure is reduced 
 below the standard amount, the regulating spring pushes 
 the piston and valve 63 up, so that air passes from the 
 main reservoir to the brake pipe. This action of the feed 
 valve maintains the pressure in the brake pipe at the 
 standard amount steadily, provided there is enough in the 
 main reservoir. 
 
 The brake pipe pressure begins to move the piston 
 down against the stiffness of the regulating spring at about 
 forty-five pounds, so that valve 63 begins to close a little 
 
58 
 
 F-6 FEED VALVE 
 
 at that pressure. As the pressure increases it compresses 
 the spring more, until at seventy pounds piston 74 is down 
 so the valve 63 has entirely closed. On account of this 
 
 FEED VALVE OPE/tf 
 
 FEEO V&JLVECJLOSED 
 
 action of the F-6 feed valve the passage of air from the 
 main reservoir to the brake pipe was free up to forty- 
 five or fifty pounds, and was then gradually restricted as 
 the pressure raised, so that between sixty-five and seventy 
 pounds the opening was so small that with a long train 
 or much leakage it took a long time to feed up between 
 those pressures. 
 
 To stop the piston in case the brake valve is in full 
 release position, the lower part of the piston comes against 
 the top part of the spring case 69, in the illustration the 
 piston is shown in this position, in service it moves down 
 only far enough to allow valve 63 to close. The small 
 
F-6 FEED VALVE DEFECTS 59 
 
 spring 64 closes the valve when the piston moves down. 
 
 The two gaskets 72 are intended to stop any brake 
 pipe air leaking by the piston. There is a recess in bush- 
 ing ring 75 deep enough to hold the smaller gasket when 
 the piston is down. If this gasket is too thick for this 
 recess it will hold up piston and feed valve so that brake 
 pipe pressure will get too high. ' If spring case 69 is 
 screwed up too far into valve body 62, the edge of the 
 larger gasket will be smashed out thin, the two gaskets 
 will then fill the recess in 75 and hold the piston up and 
 valve 63 open, which will allow brake pipe pressure to 
 feed up too high. 
 
 If the stem of valve 63 that runs up into the cap nut 
 65 gets bent, the valve will not seat squarely, and air will 
 leak past it steadily. 
 
 A leak through the gasket 56 from port f to port i will 
 allow air to pass from the main reservoir to brake pipe 
 without passing valve 63. 
 
 Do not confound this leak with a leak through gasket 
 61 in the brake valve, which allows the air from main 
 reservoir to flow into chamber D in any position except 
 full release. A leak through the feed valve affects the 
 pressures in running position only, as that is the only 
 position in which air can pass the rotary to the feed valve. 
 
 The feed valve attachment must be kept clean if it is 
 expected to work correctly. If the valve 63 gets gummy 
 so that it is not air tight on its seat, the main reservoir 
 will tend to equalize with the brake pipe at more than the 
 standard amount. 
 
 The Slide Valve Feed Valve, G-6, which is a later type 
 than the F-6, is show r n in two positions, has a slide valve 
 55, to open and close the air supply port b, and allow air 
 to pass from the main reservoir to the brake pipe when 
 the rotary is in running position. This supply valve is 
 operated by a piston, 54, which is moved in one direction 
 by the main reservoir air pressure, in the other by a 
 spring, 58. 
 
 To aid the reader we have prepared two sketches of 
 
60 
 
 G-6 FEED VALVE 
 
 this feed valve in which the parts and passages are shown 
 in such relations to each other that the flow of air through 
 the complete valve may be more easily understood. 
 
 With the G-6 feed valve the pressure of the main 
 reservoir air against the piston, 54, must be sufficient to 
 push it over against the strength of the spring 58, before 
 the slide valve will be moved to uncover port b. With 
 this valve at work feeding up the brake pipe the main 
 reservoir will show slight excess pressure at all times. 
 This you do not see with the F-6 valve, as its feed valve 
 is not held open by the main reservoir pressure. 
 
 Main reservoir air enters at f, passes into the slide 
 valve chamber F on top of, around the ends and sides of 
 
 Suide v*c~e Feed v^lvc 
 OPEN POSITION 
 
 Slide-Val/vje Feeo V^lve. 
 CLOSED POSITION 
 
 valve 55 and against piston 54. Chamber E, on the other 
 side of the piston, is connected through passage c with the 
 chamber around regulating valve 59, and if this valve is 
 open, air from E will pass through a into the brake pipe 
 
G-6 FEED VALVE 61 
 
 through i, so that air in E can equalize with that in the 
 brake pipe. 
 
 A diaphram, 57, which consists of two thin brass sheets 
 keeps the brake pipe air from escaping to the atmosphere 
 through the spring case, this diaphram rests on a piston, 
 64, which is held up by the regulating spring 67. T he- 
 stem of the regulating valve 59, rests against this dia- 
 phram, when 57 moves over, the regulating valve moves 
 with it. With reservoir pressure in F and brake pipe 
 pressure in E, the piston and slide valve moves from the 
 position shown in Fig. 4 to that shown in Fig. 3, so that 
 the port is open at b, allowing air to pass from / to L 
 Piston 54 is not a tight fit in its bushing, while the main 
 reservoir pressure is holding it over against the spring 
 58, air is leaking by the piston steadily from F into E and 
 thence through passage c, past the regulating valve and 
 passage a into the brake pipe; in addition to what goes 
 in at port b so that air is feeding into the brake pipe 
 through two passages b and c. 
 
 When brake pipe pressure reaches the standard amount 
 it has moved the diaphram and its piston over against the 
 resistance of spring 67 and allowed valve 59 to seat as 
 shown in Fig 4. This stops the passage of air from E 
 to brake pipe, piston 54 not being an air tight fit, air 
 from F soon equalizes with E. Spring 58, which was 
 compressed when the piston moved towards E, now 
 reacts, pushes 54 and 55 back into position shown in Fig. 
 4, this stops the flow of air through b into the brake pipe, 
 as the regulating valve has stopped the flow of air from 
 E, no more air passes in at either place, and brake pipe 
 pressure will not rise any higher. When brake pipe 
 pressure falls below the standard amount, the regulating 
 spring will move the piston 64 and diaphram enough to 
 unseat valve 59, air in E can then equalize with brake pipe, 
 reservoir pressure in F at once moves the piston and slide 
 valve as shown in Fig. 3 and air feeds into brake pipe 
 again. 
 
 If the regulating valve leaks, if either of the cap nuts 
 
62 
 
 B-6 FEED VALVE 
 
 53 or 61 leak, or if the spring 58 is too weak, or gone, the 
 piston will hold slide valve open so that brake pipe press- 
 ure may get too high. If the opening by the seat of the 
 regulating valve is stopped up, or the regulating spring is 
 too weak, the slide valve will be closed. To clean valve 
 59 leave rotary in service position and take off cap nut 61. 
 To clean piston 54 remove cap nut 53. Piston 54 has no 
 packing rings, it should be clean and free from gum. 
 
 If the feed valve is dirty and gummed up it will act 
 so slowly that the head brakes are apt to creep on when 
 you go to running position after a release. 
 
 The B-6 feed valve is much the same as the G-6, the 
 first ones B-4 had a small port drilled through the piston 
 8 and a packing ring 9, that regulates the supply of main 
 reservoir air passing into the chamber G behind the 
 piston. The later valves B-6 do not have this air port 
 and packing ring. In all respects the operation of the 
 piston with its supply valve, and the regulating valve is 
 the same as the G-6 feed valve. But there is a quick 
 
 DIAGRAM OF B^ FEED VALVE, CLOSED 
 
 DIAGRAM OF B^6 FEED VALVE, OPEN 
 
 thread screw on the regulating nut 23 that allows a change 
 to be made in the tension of the regulating spring 18 so 
 that the pressure of the brake pipe air can be changed 
 
REGULATING THE FEED VALVE 63 
 
 from 70 to 110 pounds, or vice versa, by a partial revolu- 
 tion of the small hand wheel that is part of the regulating 
 nut 23. Secured to the spring case 19 are two split rings. 
 
 20 and 21, a small screw 22 binds the ends of the split 
 ring when once adjusted so it cannot slip around on the 
 spring case 19. The feed valve is first adjusted to close 
 at the lower pressure, say 70 pounds, and the split ring 
 
 21 brought against the pin fixed in the hand wheel 23. 
 The wheel and adjusting nut 23 are now turned to in- 
 crease the tension on the spring 18 till the valve will close 
 at the higher pressure, say 110 pounds, and the split ring 
 
 22 is moved against the other side of the pin in 23. By 
 turning 23 so the pin rests against one or the other of 
 the stops on the rings 21 or 22, the tension of the spring 
 is adjusted for the proper pressures. This type of feed 
 valve is usually attached to a pipe bracket, as shown in 
 the cut, but it can be attached to the 1892 model valve the 
 same as the G-6 feed valve. When so used it will do 
 away with the pipe bracket, the reversing cock and one of 
 the two G-6 feed valves used with the high speed brake. 
 
 16. Q. What pressure does the black hand of the 
 double gage show, and why? 
 
 A. It shows the pressure in chamber D above the 
 equalizing piston in the brake valve, and in the brake 
 valve reservoir, it is connected to the pipe from chamber 
 D to the small reservoir and not to the brake pipe. It is 
 connected in this manner because when applying the 
 brake the engineer must know exactly how much he re- 
 duces the brake valve pressure over the equalizing piston, 
 therefore the black hand must show the exact pressure 
 there while making a service reduction. If the brake is 
 set with a direct or emergency application the gage does 
 not at once show the exact brake pipe reduction. 
 
 17. Q. In what position of brake valve does it also 
 show the exact brake pipe pressure? 
 
 A. Full release, running position, or anywhere between 
 full release and lap. In these positions the equalizing 
 port g which is the communication between the brake pipe 
 
64 BLACK HAND PRESSURE 
 
 and the chamber D, is open. In any other position this 
 port is shut to the brake pipe pressure so it is not con- 
 nected to the black hand direct. 
 
 18. Q. Then the black hand does not show the exact 
 brake pipe pressure when on lap or past lap towards the 
 emergency position? 
 
 A. No, not immediately, and you can easily prove 
 this by placing the valve on lap and opening the angle 
 cock at rear end of tender ; the brake pipe pressure will 
 drop to nothing at once, which the black hand will not 
 do. Usually the equalizing piston packing ring leaks a 
 little, and the black hand will drop back slowly as the air 
 leaks out into the empty brake pipe; if there are no leaks 
 in the brake valve, or connections to gage or brake valve 
 reservoir, it will not drop any. Unless the packing ring 
 leaks considerable it does little harm. A very small leak 
 is an advantage as it will show on the black hand the 
 brake pipe pressure as soon as the pressures can equalize 
 past the piston, it can warn the engineer if valve is left 
 on lap and brake pipe pressure falls slowly without setting 
 the brake. 
 
 If the air in the brake pipe and chamber D can equalize 
 past piston 47 the black hand will show brake pipe press- 
 ure; when auxiliaries have equalized with brake pipe, it 
 will show both pressures. 
 
 19. Q. When the brake valve has been left on release 
 position till brake pipe and main reservoir have equalized 
 at seventy pounds, and is then placed on running position, 
 are the brakes apt to creep on at once? Why is this? 
 
 A. When the valve is placed on running position, it 
 shuts off the air from brake pipe till the excess pressure 
 is picked up in the main reservoir to force the air past 
 feed valve; before this excess is picked up if the brake 
 pipe leaks, the brake will set. In such a case, run your 
 pump a little faster for a few minutes — not over five — 
 so as to get the excess quicker. If train is under motion 
 and you feel a brake dragging, put the brake valve in full 
 release for a second only, then place it in running posi- 
 
BRAKE VALVE POSITIONS 65 
 
 tion ; this may have to be done a second or third time 
 until air begins to go through feed valve, when it will 
 hold brakes off. A short rule for this is: Keep your 
 excess all the time by not using the full release position, 
 except at the time of releasing the brakes, then running 
 position will hold them off. 
 
 20. Q. Please state the different positions of the brake 
 valve, the course the air takes passing through it, and 
 what ports are covered in each position. 
 
 Note — To aid the student we have prepared some 
 sketches of the D-8 brake valve that form its construc- 
 tion and is more easily explained than the later valves, in 
 which the rotary 13 is shown as if it were a long valve 
 sliding in a straight line back and forth over a valve seat 
 instead of turning on a center as the actual rotary valve 
 really does. In these sketches the rotary is shown as if 
 cut between the preliminary exhaust cavity p and the 
 emergency exhaust cavity and straightened out as a hoop 
 is straightened out when cut across. The ports are shown 
 in somewhat changed positions so they will be in proper 
 communication with the ports and cavities in the sliding 
 valve 13. Ports a and g are shown in the sketch as if 
 they communicated with each other, in the actual rotary 
 valve a is nearer the center than g, so in service they do 
 not register with each other. In actual service port / 
 registers with / in running position as shown, and with 
 port g in emergency position ; but for the purposes of ex- 
 planation the sketch gives a very good idea of the course 
 of the air in the various positions of the D-8 valve. 
 
 A. When on full release position, main reservoir air 
 which comes in the brake valve on top of the rotary can 
 pass through opening a in the rotary into a cavity in 
 the rotary valve seat b and from there around the bridge 
 in rotary and into the brake pipe direct; in this position 
 the main feservoir and brake pipe pressures can equalize. 
 The air from main reservoir also passes through the feed 
 port ; in rotary valve into the supply port e for the pre- 
 liminary exhaust and down into chamber D. Air can also 
 
Full pel ease 
 
 Running S Position % 
 
DIAGRAMMATIC BRAKE VALVE 
 
 67 
 
 pass into chamber D from the brake pipe cavity c in rotary 
 valve through equalizing port g. In this position the 
 warning port is open so main reservoir air blows through 
 rotary into main exhaust port. The preliminary exhaust 
 and emergency exhaust ports are closed as well as the feed 
 port / leading to the excess valve or feed valve. 
 
 When on the next position, called running position 
 because it is the proper position when train is running 
 with brakes released, the direct supply port is covered so 
 that main reservoir air can not get into brake pipe direct, 
 the supply port e is also covered so no main reservoir air 
 can pass through into chmber D. The feed port / is 
 opened and main reservoir air must then pass through this 
 port and go past the excess valve or feed to get into the 
 brake pipe. Brake pipe air can pass through the cavity 
 c under rotary and go through port g into chamber D and 
 equalize the pressure on both sides of the equalizing 
 piston. The small warning port is covered. On lap posi- 
 
 tion all ports are closed so no air can pass under or 
 through the rotary. On service application position the 
 preliminary exhaust port h is opened so air flows out of 
 chamber D ; this is done by a movement of the rotary, the 
 equalizing piston opens the brake pipe exhaust port auto- 
 matically. All other ports are closed. 
 
 On emergency position the direct application port is 
 opened, allowing the air in the brake pipe to pass directly 
 
$£flV/C£ /?FP/./C/?T/OA/ /=>0<S/T/OA/. 
 
LEAKS 69 
 
 to the atmosphere through the cavity under the rotary. 
 As this is the largest port in the brake valve, if it is opened 
 wide the air in the brake pipe will escape suddenly. 
 
 The preliminary exhaust port is left open, all other 
 ports are closed. The port from brake valve to brake 
 valve reservoir is open at all times. 
 
 21. Q. Do leaks in the brake valve interfere with its 
 work? 
 
 A. Yes; if there is a leak under the rotary valve from 
 the main reservoir to brake pipe, the brake pipe pressure 
 will raise so that the brake will release when valve is on 
 lap. A leak from brake pipe under rotary valve, or 
 through brake pipe discharge valve to atmosphere, or a 
 leak between equalizing reservoir and brake valve when 
 valve is on lap, will set the brake tighter than you want 
 it. If it leaks through gasket from main reservoir to 
 cavity over equalizing piston 47 in F-6 valve, or past 
 gasket 18 in the H-type valve, brake cannot be set in 
 service application, as air will flow into chamber D from 
 main reservoir as fast as it flows out of preliminary 
 exhaust. Using the brake valve on emergency habitually 
 will tend to cut the rotary and seat quicker, as it brings 
 sand and scales of iron rust up from the brake pipe on 
 the seat, which the service application will not do. If 
 the brake valve is fastened close to the boiler head so it 
 gets very hot, the leather gaskets get burned and crack 
 so they leak badly. A bad leak past the equalizing piston 
 will cause engine brakes to release when set with a light 
 direct application. This is because air leaks from equal- 
 izing reservoir past piston and raises brake pipe pressure 
 in the short brake pipe on engine and tender. This leak 
 will also prevent the equalizing piston raising -when mak- 
 ing a service reduction if the air can come past the piston 
 into chamber D as fast as it is discharged through pre- 
 liminary exhaust port. It also makes the brake pipe re- 
 duction less than the gage at first shows, on a long train. 
 
 22. Q. What is the effect if equalizing reservoir pipe 
 is broken so a blind joint has to be made? 
 
70 BROKEN EQUALIZING RESERVOIR PIPE 
 
 A. The brake cannot be set with a gradual application 
 in service position ; there is so little air above the equal- 
 izing piston, it escapes out of preliminary exhaust so 
 quickly that the pressure above piston is reduced more 
 than twenty pounds, equalizing piston stays up and the 
 brake works with full application; some times emergency 
 with a very short train. 
 
 23. Q. What should you do in such a case? 
 
 A. If joints cannot be made so as to use equalizing 
 reservoir again, a blind joint should be made at its con- 
 nection with brake valve; the elbow in brake pipe exhaust 
 should be plugged and valve used with direct application 
 port, taking care to make a gradual reduction so brake 
 will not go on with emergency, and closing valve slowly 
 so the brakes on head end will not be kicked off. The 
 elbow has a thread cut in it for plugging; if it is not 
 threaded take it out and plug the hole with the plug in 
 the equalizing reservoir. A Y% plug is used with, the 
 type H valve. 
 
 24. Q. With the equalizing discharge valve, why does 
 the air blow out of the brake pipe exhaust when brake is 
 released, if working brake on engine and tender only? 
 
 A. Because the brake pipe is charged up through a 
 large hole in rotary valve; the cavity over equalizing 
 piston and brake valve reservoir is charged from the main 
 reservoir through the small supply port e for preliminary 
 exhaust, and by equalizing port g. If the brake pipe is 
 short, it will charge up to a full pressure quicker than the 
 space above piston; brake pipe pressure will then raise 
 piston and discharge valve, allowing air to blow out of 
 brake pipe exhaust elbow for a second or two. There 
 is no flash of air from the type H brake valve when 
 coupled to any cars. A short flash of air comes from the 
 H type when additional cars are cut in, if the H-5 valve 
 is on lap, the H-6 on running position, as air will blow 
 out of the application chamber caused by the brake pipe 
 reduction. 
 
BRAKE PIPE EXHAUST 71 
 
 25. Q. Can this action of the valve be of advantage 
 to you? 
 
 A. Yes ; if you hear this escape of air from brake pipe 
 exhaust when releasing brake on a train, it is a sign of a 
 short brake pipe ; and is a notice to the engineer that an 
 angle cock at the head end of train is closed, or something 
 has got into the brake pipe and stopped it up. You should 
 see at once if an angle cock is not shut by some mistake 
 or malicious intent. Check chains swinging against the 
 handle will close it. 
 
 26. Q. Does the amount of air which blows out of 
 brake pipe exhaust when setting the brake with a service 
 application give you any idea of the number of cars in 
 your train working air? 
 
 A. Yes, with engine and tender only, the brake pipe 
 exhaust does not blow much, if any, longer than pre- 
 liminary exhaust. With a long train it takes some seconds 
 for the brake pipe pressure to be reduced and equalize its 
 whole length. You can, after some practice, tell whether 
 you have a long or short train working air by listening to 
 the amount of air escaping from barke pipe exhaust. This 
 test shows the length of brake pipe cut in and filled with 
 air, not the number of brakes that set. It takes consider- 
 able practice to tell how many cars are coupled on. By 
 this test it gives the number of car lengths of brake pipe 
 in use ; if the triple is cut out on any car it gives you no 
 notice. When some of the cars are cut out by closing 
 angle cocks, a less amount of air will come out than with 
 all of them. It is important to know this, as some of the 
 angle cocks may be closed, thus cutting off all the cars 
 behind the closed one. In making a test for the length of 
 brake pipe connected to the brake valve, reduce your brake 
 valve pressure exactly five pounds by the gage and then 
 note the amount of air coming out of the brake pipe ex- 
 haust. Always use the same amount of reduction as there 
 is no sure way to compare the length of brake pipe exhaust 
 for different trains unless the same brake valve reduction 
 is used as a measure each time. A partly opened angle 
 
72 DOUBLE HEADING COCK 
 
 cock can be detected by this test, for the air will flow with 
 a strong, steady sound from the brake pipe ahead of the 
 partly opened cock, while the air from the pipe behind it 
 will string out longer and weaker than it should. Look 
 out for this, as the brakes can all be set. but as the air 
 equalizes very slowly into the rear cars some of the triples 
 in rear cars are liable to stick. With a full train of quick- 
 service triples considerable brake pipe air goes through 
 these triples to the brake cylinder; so a less amount of air 
 will come out of the brake valve from the brake pipe than 
 with the older form of triples. 
 
 27. Q. What is the stop cock under brake valve for? 
 Will it assist you in locating leaks? How? 
 
 A. To cut out the brake pipe from brake valve when 
 double heading, so only one engineer can control all 
 the brakes. For this purpose it is absolutely necesary. 
 Yes, it will assist in locating leaks. When shut, after 
 charging brake pipe and auxiliaries, if there is a leak in 
 brake pipe, brake will set at once ; if the rotary leaks either 
 into or our of the brake pipe, it will show it very soon, as 
 there is so short a brake pipe to leak into or out of. A 
 little observation will teach you many ways of using this 
 cut-out cock in testing for leaks. With the H-5 valve 
 and the distributing valve this stop cock controls the ex- 
 haust from the distributing valve. 
 
 28. Q. If you had an 1892 or an H-type valve and the 
 brake would not go on in service application, nor the black 
 hand fall, nor the brake pipe exhaust open, while air came 
 readily from preliminary exhaust, what would be the 
 matter ? 
 
 A. I would look for a leak at the joint on lower gasket 
 where a leak would allow air to get from main reservoir 
 direct to cavity over equalizing piston No. 47. This would 
 give main reservoir pressure to chamber D and show it on 
 the black hand. A brake valve with this leak would show 
 very little or no excess pressure. No ajr could come out of 
 brake pipe exhaust, as the pressure could not be reduced 
 over the piston so valve could be raised. To set the brake 
 
DISABLED BRAKE VALVE 73 
 
 use direct application port, opening and closing it slowly. 
 
 29. Q. If you had a continual blow at the brake pipe 
 exhaust port of the brake pipe valve and could hold no air, 
 where would the difficulty be apt to be found? 
 
 A. Stuck or leaky equalizing piston, dirt on its valve 
 seat, brake valve reservoir bleed cock open, or bad leak in 
 pipe to brake valve reservoir or gage. Would put valve 
 on lap, then on emergency for a moment and see if that 
 would stop it, or close the stop cock under the valve and 
 flash the valve to clean off the seat. 
 
 30. Q. How should the brake valve handle be placed 
 when running or standing with brake released, unless 
 auxiliaries are being charged? Why? 
 
 A. Always in running position. Because this is the 
 only position in which you can carry excess pressure, 
 which is needed to release brakes promptly. With 1892 
 valve on full release the brake pipe pressure will run up as 
 high as pump governor will allow; this high pressure is 
 apt to slide the wheels. A small blow hole is put in the 
 rotary valve to warn engineer that valve has been left 
 in full release. All valves should have this warning port; 
 if it gets stopped up, it is a sign that there is dirt on 
 top of rotary valve,. which should be taken out and cleaned 
 at once. When on running position the opening through 
 brake valve from main reservoir to brake pipe is a smaller 
 one than on full release. If the train breaks in two or 
 conductor's valve is opened to stop the train in case of 
 accident, the brakes will operate instantly as the brake pipe 
 pressure can be reduced from the train faster than the 
 running position feed port can supply it. If the valve is 
 on full release the brakes will not set tight till the main 
 reservoir pressure is also reduced. If necesary to hold 
 engine brakes with the H-type valve after a release of 
 train brakes, use holding position. 
 
 31. Q. What are the essential differences between 
 the 1892 model and the 1906 or H-5 brake valve? 
 
 A. The H-5 brake valve has all the pipe connections 
 made at the bottom section or pipe bracket, so the valve 
 

 H/£ AUTOMATIC BRAKE VALVE 
 
H-5 BRAKE VALVE 75 
 
 can be removed from the engine without disturbing any 
 pipe joints. The feed valve is located on a pipe between 
 the main reservoir and brake valve. The brake valve 
 receives main reservoir air direct through one pipe. This 
 air comes on top of the rotary. Air at a reduced pressure 
 comes through the feed valve and another pipe; coming 
 under the rotary at port d. The preliminary e and emer- 
 gency exhaust x is through the center of the rotary o into 
 the cavity EX in section 3 of the valve and thence to the 
 atmosphere. The brake pipe exhaust is at the bottom and 
 in the center of the valve. This valve is intended to be 
 used in connection with an independent brake valve and 
 the distributing valve for the locomotive brake and has 
 two pipe connections for this purpose. In the rotary valve 
 seat there is a port / that connects with the pipe leading 
 from the application chamber of the distributing valve 
 through the independent brake valve. When the rotary 
 is in running position port h in the rotary registers with /, 
 if the independent valve is also in running position, the 
 locomotive brake will be released. 
 
 There is another position of the H-5 valve, called hold- 
 ing position, located between running and lap, in which 
 port h does not register with port I, but air coming through 
 the feed valve can pass out of d through f in the face of 
 the rotary into b, thence through a cored out passage to 
 c and the brake pipe leading to the train. With the H-5 
 valve in holding position the train brake will be re- 
 leased and the locomotive brake held set. This port / is 
 also lapped in full release, so that the train brake can be 
 released and at the same time the engine brake be held 
 set if required; this will hold the slack back in the head 
 end of the train and make it safe to release the train brake 
 at slow speeds, and not break in two. Another port u in 
 the rotary seat connects with the double heading pipe, port 
 h registers with u in lap position. This pipe leads from 
 the exhaust port of the distributing valve and is only used 
 on the following engine of a double header. When the 
 
76 H-5 BRAKE VALVE 
 
 double header cut out cock under the brake valve is closed 
 this pipe connection through the cock is open. 
 
 In the emergency position of the rotary, port / in the 
 seat registers with port g through the groove n in the 
 face of the rotary so that in emergency position air from 
 the brake valve reservoir can flow into application chamber 
 of distributing valve and apply the engine brake with 
 greater force. Port p connects with the excess pressure 
 head of the pump governor, when the rotary is in full re- 
 lease, running or holding positions; main reservoir air 
 can pass through port ^ in the rotary and the small groove 
 in its face and enter port p, thus controlling the excess 
 presure head of the governor in these positions. In full 
 release main reservoir air from port s flows through the 
 warning port r into EX and gives the warning that the 
 valve is in full release position. In service position port h 
 in the rotary registers with e in the seat, air from cham- 
 ber D flows into o and EX, all other ports in the seat 
 are closed. The action of the equalizing piston 15 has 
 already been, described. Cavity k in the face of the rotary 
 connects ports g and c in runing and holding positions, 
 so that brake pipe and chamber D charge up alike in these 
 positions and there is no flash of air from the brake pipe 
 exhaust when releasing brakes with a short train. 
 
 Plug 29 can be taken out and some good oil poured 
 in the cavity around the lower edge of the rotary to lubri- 
 cate it. Spring 30 holds the rotary key 7 up against gasket 
 8 when there is no air pressure to do this, in full release 
 position main reservoii air passes thro ugh ports a in the 
 rotary and directly into port b and the brake pipe, and port 
 quickly. In running and holding positions cavity f in the 
 face of the rotary connects ports d and b so the air that 
 has been reduced in pressure at the feed valve can flow 
 into the brake pipe and charge it up to the pressure that 
 the feed valve closes it, and no higher. To take the H-5 
 valve off its pipe bracket take out the through bolts. To 
 take the valve apart take out the tap bolts that hold the 
 valve sections together. 
 
INDEPENDENT BRAKE VALVE 77 
 
 32. Q. Describe the independent brake valve. 
 
 A. This valve is used in connection with the distribut- 
 ing valve and allows air to flow into or out of the applica- 
 tion chamber, and thus operate the supply valve piston, 
 that in turn operates the valves which admit main reser- 
 voir air to the brake cylinder to set the engine brake or 
 exhausts the cylinder air to release it. It does not admit 
 main reservoir air direct to the brake cylinder as the 
 Straight Air brake valve does. It has four positions, 
 release, running, lap and service, that come the same as on 
 the automatic brake valve. A stiff spring 9, in the top of 
 the valve body 3 returns the handle from release to run- 
 ning position as soon as the engineer removes his hand. 
 
 In running position port d from the distributing valve 
 is connected through port f in the rotary 5 with port c 
 leading to the automatic valve, so that air can flow from 
 the application chamber through the independent valve to 
 the automatic brake valve, and this valve should always 
 be in running position when the automatic valve is to 
 operate the engine brake. In release position cavity g in 
 the face of the rotary 5 connects port d with the exhaust 
 port h in the center of the seat, so that the application 
 chamber air can pass to the atmosphere without regard to 
 the position of the automatic brake valve and release the 
 engine brake independently of the train brake. In service 
 position cavity e in the rotary connects the supply port b 
 with d so that main reservoir air reduced to 45 pounds can 
 flow direct to the application chamber and operate the dis- 
 tributing valve supply piston; this position applies the 
 engine brake independently. Lap position blanks all ports 
 and is to be used only when making a graduated applica- 
 tion or release of the engine brake or when trying to 
 prevent the release of the engine brake by the automatic 
 valve, or the passage of air from the brake valve reser- 
 voir through the automatic valve in the emergency posi- 
 tion to the application chamber. Leaving the independent 
 valve in lap position when operating the automatic valve 
 
78 
 
 INDEPENDENT BRAKE VALVE 
 
 is liable to cause trouble. This valve does not affect the 
 operation of the train brake in any way and is to be used 
 
 automatic e**K£ vAive 
 
 Distributing VACVt 
 
 \ St*VICl, 
 
 SEST) 
 
 INTERIOR VIEWS OF THE INDEPEND 
 -ENT BRAKE VALVE 
 
 when operating the engine brake while switching cars, 
 or independently at any time. Its supply of air comes 
 from the main reservoir through a reducing valve set at 
 45 pounds. The arrangement of these valves is shown in 
 the page illustration and they are part of the ET locomo- 
 tive brake equipment. The location of each valve in this 
 type of brake is plainly shown, so no description is given. 
 
 33. Q. Describe the distributing valve in its construc- 
 tion and operation. 
 
 A. The distributing valve is shown separately and 
 attached to its double-chambered reservoir. The pressure 
 
80 
 
 THE DISTRIBUTING VALVE 
 
 chamber represents an auxiliary reservoir and the applica- 
 tion chamber the brake cylinder as regards the equaliza- 
 tion when the air passes to the application chamber; this 
 comparison is for explanatory purposes only. There are 
 five pipe connections, only two of which show on the ex- 
 
 fnpcTAP 
 
 TO WMEP6NOCNT 
 'ffMlX VAUVC 
 
 posed side of the reservoir. On the next page is shown a 
 diagrammatic view of the valve and reservoir, in which 
 the valve is shown much larger in proportion to the size 
 
22 
 
 m 
 
 RELEASE, AUTOMATIC OR 
 INDEPENDENT 
 
82 THE DISTRIBUTING VALVE 
 
 of the reservoir than it really is. We will use capital let- 
 ters as abbreviations for the names of the five pipe connec- 
 tions made to the reservoir and from there to the various 
 parts of the valve. In the diagrammatic view slide valve 
 31 and graduating valve 28 are shown both above and 
 below the piston stem 26, so the ports that are beside each 
 other can be seen. Air from main reservoir enters at sup- 
 ply, passes through port a up and around application valve 
 5; also down to seat of slide valve 31 and through 
 port n to the pressure chamber when valve 31 is in 
 emergency position. Air from the brake pipe enters at 
 BP and is on the outside of equalizing piston 26. When 
 this piston is in release, as shown, brake pipe air can pass 
 around the piston through the feed port into the pressure 
 chamber. When thte brake pipe pressure is reduced piston 
 26 moves back towards the reducing train pipe pressure, 
 bringing first graduating valve 28 and then moving slide 
 valve 31 as soon as the lost motion between the shoulders 
 on piston stem and valve 31 is taken up. This admits 
 air from the pressure chamber to the application 
 chamber through ports o and h, and in this respect is 
 exactly like a triple valve when feeding air from the 
 auxiliary to the brake cylinder. With a partial application 
 of the automatic brake equalizing piston 26 and its 
 valves reduces the pressure in the pressure chamber by 
 allowing air to pass into the application chamber till the 
 pressure chamber is a trifle lower than the brake pipe 
 when piston 26 moves back and laps graduating valve 28. 
 This movement has been fully explained in connection 
 with the triple valve. 
 
 At the same time that air flows into the application 
 chamber, it also flows up through port h into the space g 
 behind the application piston 10. This moves application 
 valve 5 and as soon as the lost motion is taken up, 
 exhaust valve 16 covers the exhaust ports e and d. 
 Valve 5 next opens the supply port from a into b and c, 
 so main reservoir air can flow to the brake cylinder at BC 
 and apply brake. We will suppose a 7-pound reduction 
 
OPERATION OF DISTRIBUTING VALVE 83 
 
 is made in the brake pipe. As soon as it is felt on the 
 piston 26 at p it will move towards BP, open valves 28 
 and 31 closing exhaust port k Air will flow into the 
 application chamber and cavity g till the pressure cham- 
 ber is also reduced 7 pounds, when piston 26 will move 
 back and lap valve 28 over the port in valve 31. Air 
 pressure in g will then move piston 10 and its valves 
 5 and 16, "closing the exhaust ports c and d and opening 
 supply port from a to c. To open port from a the gradu- 
 ating stem 19 must be moved back against the tension of 
 its spring 20, when the stem 19 meets cap nut 22. As 
 soon as the presure in b and the engine brake cylinders 
 is equal to that in that in g on the other side of piston 10, 
 spring 20 and the stem 19 will move piston 10 and valve 5 
 back to lap, but does not move valve 16 to open the ex- 
 haust. This applies the brake and holds it applied as long 
 pressure remains in g and h. If leaks in the brake cylin- 
 der packing or piping reduce the pressure in b, piston 10 
 will move towards this lecreasing pressure and open the 
 supply port till the pressure in the cylinder again equals 
 that in g, when piston 10 will lap valve 5. When the air in 
 the application chamber is either wholly or partly ex- 
 hausted to the atmosphere, piston 10 will be moved back 
 towards g by the brake cylinder pressure and either wholly 
 or partly exhaust the air from the cylinder. 
 
 In the independent application and release of the 
 brake through the distributing valve the lower or equal- 
 izing piston 26 and its valves do not move. The air is fed 
 into and out of the application chamber and chamber g 
 by the independent brake valve at the pipe connection AC. 
 This air comes from the main reservoir and is reduced to 
 45 pounds presure befoure passing through the independent 
 brake valve. When the independent valve is in service 
 position air flows in at AC till the pressure in the appli- 
 cation chamber and g is enough to apply the brake the 
 desired amount. A partial or full application can be made 
 depending on how much air is admitted through the brake 
 valve, and a partial or full release by lapping the brake 
 
84 OPERATION OF DISTRIBUTING VALVE 
 
 valve before all the air has escaped. To prevent the air 
 passing out the exhaust port k of valve 31 when in re- 
 lease position port i is piped at DH to the double heading 
 cock in the brake pipe under the automatic brake valve. 
 When this cock is open for the brake pipe, as it should be 
 when the automatic brake is being operated from that 
 engine, the pipe leading from the exhaust port k is closed 
 so no air can escape through valve 31 when in release 
 position. But if this engine is not operating the train 
 brake in a double header the exhaust port k is open 
 through a pipe from DH through the cut-out cock and a 
 port in the H-5 automatic brake valve when the rotary 
 is in lap position. 
 
 There is a cut-out cock in the brake pipe connection 
 before reaching BP to cut out the distributing valve from 
 operating automatically when necessary. Closing this cut- 
 out cock does not prevent the brake being operated by 
 the independent brake valve. 
 
 When the automatic brake valve is in the emergency 
 position air from the brake valve reservoir can flow 
 through a port in the H-5 valve, then through the inde- 
 pendent valve — if it is in running position — into the 
 application chamber and g, so that the engine brake can 
 be applied in that position of the automatic valve, even 
 if cut out from the brake pipe. This is a feature of the 
 H-5 only. 
 
 When piston 26 is moved its full travel to the emer- 
 gency application position so it rests against gasket 25 in 
 cap 23, ports n in the bushing and m in valve 31 will be 
 open to each other so main reservoir air can flow slowly 
 through the small port n into the pressure chamber and 
 increase the pressure there. At the same time port / is 
 open to the safety valve 34 and it will reduce the pressure 
 there to about 60 pounds. This feature is intended to 
 operate the brake the same as the high speed reducing 
 valve. In the No. 5 distributing valve (the one here 
 described), port / is only open to the pressure chamber 
 
<*.-SAFETY VALVE ' 
 
 No. 6 E. T. EQUIPMENT 85 
 
 and port h in application position; being 
 closed in release and lap positions of valve 
 28 and 31. For this reason, when using the 
 independent brake valve only with the equal- 
 izing piston 26 in release or lap the safety 
 valve 34 will not reduce the pressure in the 
 application chamber should the reducing valve 
 for the independant valve be out of order and 
 allowing too high a pressure. This safety 
 valve is set at 53 pounds, and will blow down 
 to that with an automatic service application. 
 34. Q. Are there any differences between the No. 
 
 5 ET equipment and the later design, No. 6? Describe 
 them. 
 
 A. The No. 6 ET equipment was designed later 
 than the No. 5 just described, there are several differences 
 between the No. 6 and any previous type that enable No. 
 
 6 to get the same results easier and have many added 
 advantages. 
 
 The release pipe between the automatic brake valve 
 and the independent valve goes direct and not through 
 the double heading cock, the double heading cock of the 
 H-6 is an ordinary stock-cock the same as used with the 
 F-6 valve. In double-heading the normal position of the 
 H-6 valve is running instead of lap as with the H-5. The 
 release pipe from the distributing valve comes from the 
 application cylinder with No. 5 and from the exhaust of 
 equalizing slide valve 31 with No. 6, so that valve 31 
 must be in release position to release the distributing 
 valve through the H-6 valve. With No. 5, air could 
 come out of the application cylinder and chamber through 
 the two brake valves in running position regardless of the 
 position of slide valve "31. The application cylinder pipe 
 of No. 6 goes direct to the independent valve as before, 
 a Tee connection is put in leading to the H-6 maintaining 
 port. In No. 5 this port was in the distributing valve. 
 
 In an emergency application with the No. 6 slide valve 
 31 moves quickly and laps the port into the application 
 
No. 6 DISTRIBUTING VALVE 87 
 
 chamber so the pressure chamber equalizes with the 
 application cylinder only, at very nearly the amount of 
 pressure in the chamber at first, about 65 out of 70 
 pounds. In a service application the port to the applica- 
 tion chamber is held open so the pressure chamber equal- 
 izes with the combined volume of the application chamber 
 and cylinder at 50 out of 70 pounds. 
 
 The positions of the two smaller pipes at the bottom 
 of the distributing valve are reversed in No. 6 from that 
 in No. 5. The application cylinder pipe is the lower one 
 in No. 5 it is the upper one in No. 6 ; the lower one in 
 No. 6 connects with the exhaust of valve 31. In No. 5 
 the double heading pipe that did this work was the upper 
 one. 
 
 There is a special cap for the cylinder of piston 26, 
 containing a quick-action valve to vent brake pipe air 
 to the brake cylinders and a rubber seated check to hold 
 it there, this will hurry up the quick-action on the train 
 as a quick-action triple on a tender will do. 
 
 There is only one position of slide valve 31 of the No. 
 6 in which safety valve 43 is not connected to the applica- 
 tion cylinder, automatic lap, in all other positions the 
 safety valve will take care of the over pressure. 
 
 A careful study of the explanation of the No. 5 will 
 assist in understanding the No. 6, the points that are 
 common to both valves need not be explained again. 
 
 35. Q. Describe the H-6 brake valve and its operation. 
 
 A. The H-6 valve is similar in outside shape to the 
 H-5 ; there are differences in the air ports and cavities ; 
 using the cut of the rotary and its seat to trace the course 
 of the air in different positions will give a good idea of 
 the work of the valve. It has six positions; full release, 
 running, holding, lap, service application and emergency. 
 Main reservoir air comes in over the rotary valve at 
 MR; feed valve air at FV under the rotary at port d; 
 b is the supply port through the seat for the brake pipe 
 and c the emergency exhaust from the brake pipe, o is 
 
88 No. 6 DISTRIBUTING VALVE 
 
 the exhaust opening and x the emergency exhaust passage 
 in the rotary; / connects d and b in running position. 
 
 In full release, port a through the rotary registers 
 with port b, the brake pipe; so main reservoir air at full 
 pressure goes directly to the brake pipe in this position; 
 / in the rotary registers with g in the seat, so chamber 
 D charges with main reservoir air direct in this position; 
 Cavity f in the face of the rotary connects port d with 
 warning port r in the seat and allows a small amount of 
 feed valve air to escape to the atmosphere, serving two 
 purposes warning the engineer to move the valve from 
 full release and giving an idea of how sensitive the feed 
 valve is. Port s through the rotary has a small groove 
 at the face, this connects with port p in the seat allowing 
 main reservoir air to flow to the lower connection of the 
 excess head of the pump governor in full release, running 
 and holding positions. 
 
 In running position port a through the rotary is closed 
 at its lower end so no main reservoir air can go directly 
 to tne brake pipe, cavity f connects d and b so air from 
 the feed valve can flow to the brake pipe; cavity k con- 
 nects ports c and g, the brake pipe and chamber D can 
 now equalize. Port ^ still registers with port p leading to 
 the governor, h in the rotary registers with / in the , seat 
 that connects with the release pipe and allows air ex- 
 hausted through valve 31 from the application cylinder 
 and chamber to escape and release the locomotive brake. 
 
 When an empty train is being charged, as long as the 
 brake valve is in full release the pump will run at speed, 
 but when the valve is moved to running position the 
 action of the S-F pump governor is sometimes puzzling. 
 As one side of this governor is operated by the excess 
 pressure if the feed valve cannot pass the air to the 
 brake pipe as fast as the pump supplies it, the excess 
 will build up enough between the main reservoir and 
 brake pipe pressures to have the governor stop the pump. 
 In such a case move brake valve to full release and leave 
 
MAIN RCSEKVt/R 
 
 CdOajjzing Rcsoivem. 
 
 —THE H-6 AUTOMATIC BRAKE VALVE 
 
 it there till the brake pipe pressure is close to the 
 standard. 
 
 Holding position leaves all the ports that were open 
 
90 H-6 BRAKE VALVE POSITION 
 
 in running position still open, except I, that is now lapped 
 instead of being open to h, the distributing valve cannot 
 release through that port. This position will release and 
 charge up all the automatic parts of the brake on train 
 and engine, but hold the engine brake set. 
 
 On lap position all ports in the rotary and its seat 
 are lapped; there is no passage for air in any direction 
 through the ports. 
 
 On service position all ports are lapped, except the 
 preliminary exhaust port e, this registers with h in the 
 rotary, the air in chamber D will now pass out slowly, 
 brake pipe air will raise equalizing piston 15 and its 
 valve and discharge brake pipe air to the atmosphere. 
 
 When the H-6 ,is placed in emergency position, port 
 x in the rotary registers with c in the seat, making a 
 large opening from brake pipe to atmosphere through o 
 in the rotary and EX in the seat. The sudden reduction 
 in brake pipe pressure starts the quick-action in the train 
 brakes and applies all of them in the shortest space of 
 time. Main reservoir air is now passing through port / 
 in the rotary, thence through a small port into cavity k 
 and small port n into port u in the seat, and thence 
 through the Tee connection into the application cylinder; 
 this maintains the pressure in this cylinder up to when 
 the safety valve controls it. Port t in the rotary registers 
 with equalizing port g, air in chamber D will pass out to 
 the atmosphere instead of going to the application chamber 
 as it does with H-5. 
 
 36. Q. Describe the S-6 independent brake valve. 
 
 A. The independent brake valve S-6 has five posi- 
 tions: Release, Running, Lap, Slow Application and Quick 
 Application. A return spring 6, coiled inside the top of 
 the valve will return the handle 15 from release to run- 
 ning, and from quick application to slow application; the 
 engineer will feel the resistance of this spring when mov- 
 ing the rotary to its full travel, either way. The warning 
 port / is provided to warn the engineer in case this spring 
 is broken. Air from the reducing valve at 45 pounds 
 
S-6 INDEPENDENT VALVE 
 
 91 
 
 Rotary Valve 
 THE S=6 INDEPENDENT BRAKE VALVE 
 
 pressure comes in at port b and on top of rotary through 
 port e. Port a leads air through the release pipe IV from 
 the distributing valve exhaust of slide valve 31; port c 
 connects with the release pipe to H-6 at port e ; ports 
 a and c are connected by groove / in the rotary 9 when 
 in running position; with both valves in running position, 
 air exhausted by slide valve 31 can pass through the 
 S-6 and escape at the H-6 valve. Port d leads to the 
 application cylinder pipe II, in independent application 
 air passes in through this port and pipe to application 
 cylinder; in independent release air passes out this way. 
 A Tee in this pipe leads to the maintaining port u in the 
 
92 NO. 6 DISTRIBUTING VALVE 
 
 H-6 rotary, h is the exhaust port, exhaust cavity g in 
 rotary 9 always registers with it. k is the warning port, I 
 is the warning port in the rotary, open in release. A 
 small port m connects with groove e and registers with d 
 in slow application, passing air slowly; in quick applica- 
 tion position the larger groove e registers with d and 
 passes a large amount of air to the application cylinder, 
 setting the brake quickly. The latter part of answer to 
 Q. 32 gives directions for operating this valve. 
 
 37. Q. Explain the operation of the No. 6 Distribut- 
 ing Valve. 
 
 A. The diagrammatic view of the No. 6 distributing 
 valve gives a good idea of the application portion at the 
 top of the cut; the equalizing portion is in the middle; 
 the double chambered reservoir is at the bottom; for 
 the reference letters and numbers, look at the next 
 diagrammatic cut. Main reservoir air comes into the 
 application portion only, a pipe leads to the brake cylin- 
 ders. The movement of the application piston and its 
 two valves admits main reservoir air to the brake cylin- 
 ders or exhausts cylinder air to the atmosphere. Admit- 
 ting air at a pressure into the application cylinder will 
 move piston 10 and its valves to the right, first closing 
 exhaust ports under valve 16, next opening air port under 
 . valve 5, so main reservoir air can flow to the cylinders. 
 If we have put 10 pounds pressure against piston 10 and 
 opened the air port, air will flow in till the brake cylinder 
 pressure builds up to 10 pounds ; piston 10 will then b(. 
 balanced between the two pressures; a graduating stem 
 19, and its spring 20, in the end of the piston stem will 
 move the piston and valve 5 back to lap. Increase the 
 pressure in application cylinder, piston 10 and valve fi 
 will move to admit more air, when pressures are balanced; 
 valve 5 will close, thus the pressure can be built up in the 
 brake cylinder by admitting air to the application cylinder. 
 To release the brake, allow part or all of the application 
 cylinder air to escape; piston 10 will be moved to the 
 left by brake cylinder pressure, opening the ports under 
 
DIAGRAMMATIC DISTRIBUTING VALVE 
 
 93 
 
 valve 16 the brake will then be all or partly released, de- 
 pending on the pressure left in the application cylinder. 
 If leaks in the brake cylinder reduce pressure there, piston 
 
 TO MAIN RESERVOIR. 
 
 TO INDEPENDENT A 
 AUTOMATIC BRAKE VALVES. 
 
 TO INDEPENDENT BRAKE VALVE. 
 
 APPLICATION 
 CHAMBER. 
 
 
 PRESSURE CHAMBER. 
 
 DIAGRAMMATIC VIEW OF THE ESSENTIAL 
 PARTS OF THE DISTRIBUTING VALVE, AND 
 DOUBLE-CHAMBER RESERVOIR. 
 
94 
 
 OPERATION OF DISTRIBUTING VALVE 
 
 10 will move to the right, open supply valve 5 and build 
 the brake pressure up to equal that in the application 
 cylinder; leaks out of the application cylinder or its 
 piping will tend to release the brake. There are two 
 ways of letting pressure into and out of the application 
 cylinder ; one by way of the independent valve and H-6 
 valve, the other is by the operation of the equalizing 
 portion of the distributing; this is shown clearly in the 
 diagrammatic view of automatic service. The brake pipe 
 
 MR 
 
 AUTOMATIC SERVICE 
 
OPERATION OF THE DISTRIBUTING VALVE 95 
 
 connection supplies brake pipe air to this portion the same 
 as to a triple; air feeds around piston 26, through feed 
 port r charging up the space around valve 31; passes 
 through port o into the pressure chamber till the pressure 
 there equalizes with the brake pipe. To make an auto- 
 matic service application of the distributing valve, the 
 brake pipe pressure is reduced, piston 26 at once moves 
 to the right, a part of its full travel to the position shown 
 in the view; first moving graduating valve 28 to open 
 port z and closing feed port v. Slide valve 31 is next 
 moved to register ports z and h, air from the pressure 
 chamber flows through z, h, and w into both application 
 chamber and application cylinder g, building up a press- 
 ure against piston 10. Safety valve / is now connected 
 through ports r and s with h; this allows application 
 cylinder air access to the safety valve. Suppose we make 
 a 7-pound reduction in brake pipe and move piston 26 and its 
 valves, as soon as the air in the pressure chamber and on that 
 side of piston 26 is reduced, a little more than 7 pounds by 
 going into the pressure chamber and g; piston 26 will 
 move towards this, decreasing pressure, covering port z 
 with valve 28; no more air will pass out of the pressure 
 into the application chamber and g; the action in this 
 respect is like a triple valve feeding air from an auxiliary 
 to a brake cylinder, described on page 8. 
 
 Another brake pipe reduction will send more air from 
 the pressure to the application chamber and g 3 till the 
 pressures in these two chambers are equalized, after that 
 the pressure in g cannot rise any higher with an auto- 
 matic application. A pressure built up in g will operate 
 piston 10 and its valves to send main reservoir air to the 
 brake cylinders; exhausting air from g will release the 
 brake. To release the engine brake automatically, re- 
 charge the brake pipe till its pressure will move piston 
 26 and valve 31; to release position air from g and the 
 application chamber will then pass out under valve 31 
 through pipe IV to the brake valves, with both of them 
 in running position this air can get to the atmosphere, 
 
96 
 
 OPERATION OF THE DISTRIBUTING VALVE 
 
 piston 10 will then open exhaust valve 16 and release 
 the brake. 
 
 In the independent application and release of the brake 
 through the distributing valve, lower piston 26 and its 
 valves do not move, but remain in the position they have 
 been placed in by the automatic brake valve, changes in 
 brake pipe and pressure chamber pressures move this 
 piston. 
 
 MR 
 
 EMERGENCY POSITION OF No. 6 DISTRIB- 
 UTING VALVE WITH QUICK-ACTION CAP. 
 
QUICK-ACTION DISTRIBUTING VALVE 97 
 
 The No. 6 valve is provided with a quick-action cap 
 47, that can be used in place of the plain cylinder cap 
 23 on large passenger engines or those used* in double- 
 heading regularly. This cap 47 contains an emergency 
 valve 48 attached to the graduating stem 50, so they move 
 together and a rubber seated check 53, and its spring 54, 
 that opens to admit brake pipe air to passage m, leading 
 to the brake cylinder pipe at c. An over-reduction of 
 brake pipe air in service application will move stem 50 
 and valve 48 to open port j, but in this application brake 
 cylinder has equalized with brake pipe and no air will 
 pass the check-valve 53. When a sudden and heavy 
 reduction in brake pipe pressure is made as the first 
 reduction, piston 26 moves its full travel, at once push- 
 ing stem 50 over against the resistance of spring 55, 
 moving valve 48 to uncover port /; this makes a sudden 
 reduction of brake pipe air that will insure the quick- 
 action of triples on the train in the same way a quick- 
 action triple on the tender will. When the brake pipe 
 air equalizes with the brake cylinder, check-valve 53 
 closes so air can not pass back from the cylinders. Air 
 from the pressure chamber flashes into the application 
 cylinder and operates piston 10 to set the brake when 
 this sudden reduction operates piston 26. Valve 31 passes 
 over port w so quickly that very little air gets into applica- 
 tion chamber, pressure chamber air equalizes with applica- 
 tion cylinder g only at very near its original pressure, 
 about 65 out of 70 pounds and sets the brake at that 
 pressure. 
 
 If the H-6 valve is left in emergency position its 
 maintaining port u will pass main reservoir air through 
 pipe II and build up the pressure in g till the safety valve 
 set at 68 pounds can control it. 
 
 In High Speed Brake service with the feed valve 
 carrying 110 pounds instead of 70, the main reservoir 
 pressure is usually 130 to 140 pounds ; this pressure at the 
 H-6 valve will force more air through port w and raise 
 the pressure in g to about 93 pounds. The small opening 
 
98 . DOUBLE HEADING 
 
 between q and r in slide valve 31 is just enough larger 
 than port w so the air can be reduced to 75 pounds by 
 the safety valve; this higher pressure gives a quicker 
 stop in High Speed service. When the H-6 brake valve 
 is put in release position, after an emergency stop, and 
 the brake pipe pressure is built up enough to move piston 
 26 to release, the air in the application cylinder can then 
 equalize into the application chamber at about 15 pounds; 
 this will hold the locomotive brake set at that pressure 
 till the H-6 is moved to running position, it will then 
 fully release. 
 
 In double heading the cock under the H-6 brake valve 
 must be closed on the following engines to give the lead- 
 ing engineer control of the brakes and the H-6 and S-6 
 valves carried in running position; this will leave the 
 exhaust port of valve 31 open to the atmosphere so the 
 leading engineer can use the distributing valves on the 
 following engines, the same as triple valves on the train. 
 If necessary to release the engine brake on the following 
 engines, it should be done with the independent brake 
 valve without moving the H-6 from running position. 
 When backing up a train that is to be controlled with a 
 tail hose, the H-6 should be carried in running position, 
 unless the rules of the Company require another position. 
 
 COMBINED AIR STRAINER AND CHECK 
 VALVE 
 
 There is a connection from the brake pipe to the main 
 reservoir pipe with a stop-cock to keep it cut out when 
 not needed, and a strainer check valve to prevent air 
 from coming back from the reservoir; this for use on 
 
DEAD ENGINE CONNECTION 99 
 
 a dead engine when drawn in a train. This connection 
 will furnish a supply of air to operate the E. T. brake ; 
 the check valve is held down by a 20 pound spring, with 
 70 pounds in the brake pipe there will me 50 in the main 
 reservoir. A choke in the check case prevents air flowing 
 out of the brake pipe fast enough to affect the brakes. 
 The same type of strainer check without a spring is used 
 between the 45-pound reducing valve and the signal 
 system. The piping diagram shows the location of these 
 strainer checks. 
 
 When making a "two-application" stop with a 
 passenger train and ready to make the first release; go 
 to release position just long enough to move all the 
 triples, then to running for an instant to allow the engine 
 brake to release; the engineer's judgment must decide 
 how long; you can then come to lap or service to make 
 the second application; unless you stop an instant on run- 
 ning the engine brake will remain full set. 
 
 When operating the locomotive brake separately from 
 the cars, use the independent valve, leaving the H-6 in 
 running position. A partial or full application can be 
 made by admitting a little or much air, and a partial re- 
 lease by lapping the independent valve before all the 
 air has escaped from the distributing valve. This valve 
 can be used to bunch or hold the slack as well as to 
 hold the engine brake set when standing at a water plug 
 or on a grade. 
 
 To cut out the brake pipe from the distributing valve 
 there is a stop-cock in the branch pipe, and to cut out the 
 driver or tender brake cylinders when disabled, there are 
 cocks in the proper pipes. A choke fitting near the hose 
 connection to the tender brake will hold the driver brakes 
 set if the hose bursts or is uncoupled, as the distributing 
 valve can feed air in faster than it can get through the 
 choke. The choke is large enough to allow the tender 
 brake to set and release without delay. 
 
 The E. T. equipment must be kept clean and all the 
 pipe joints and gaskets air tight if it is to operate prop- 
 
100 E T BRAKE DEFECTS 
 
 erly. Grit or scales from the inside of the air pipes will 
 cut the seats of the valves so they will leak, and leaks 
 are the puzzle of this brake. Look out for leaks across 
 the gasket between the distributing valve and its reservoir, 
 as they occur there often. To locate leaks to the 
 atmosphere use soapsuds at the suspected joint. To locate 
 the leaks into the piping from the valves, open the pipe 
 joints at the unions between the valves, air will come 
 out from the pipe connected to the defective valve. You 
 can then follow it up to the source of the leak. In case 
 of broken pipes when out on the road, if you understand 
 the operation of the valve there need be no trouble in 
 understanding what to do and whether the brake can be 
 still operated. If you will remember that the distributing 
 valve depends on the pressure of air in the application 
 chamber to open and close the valves that control the 
 passage to and from the brake cylinder it will make the 
 operation of this valve clear to you. When air gets into 
 this chamber, whether from a leak through either brake 
 valve, the slide valve 31 or the gaskets, it will raise the 
 pressure there and apply the engine brake. Or, if the air 
 can pass out of this chamber either the regular way 
 through the brake valves or leaks in the pipe connections 
 •the engine brake will release. First study out how the 
 air gets into and out of this chamber and it will clear up 
 many things that otherwise would puzzle you. 
 
 There are several forms of the distributing valve in 
 service, with some differences in their construction and 
 operation, and it is likely that other changes will be made 
 in the valve from time to time. 
 
 38. Q. Describe the Combined Automatic and Straight 
 Air Engine and Tender brake. 
 
 A. This brake valve contains two check valves, 8 and 
 9 — see Figures 1 and 2 — to admit air from the main reser- 
 voir to the brake cylinders and 9 to exhaust the air from 
 the cylinders to the atmosphere. These valves are moved 
 away from their seats alternately by the shaft 2, which 
 when revolved to the right, forces valve 8 off its seat 
 
STRAIGHT AIR BRAKE 
 
 101 
 
 against the pressure of the main reservoir air in a and tne 
 spring 11; when revolved to the left forces the exhaust 
 valve 9 off its seat against the pressure of the spring 10 
 and the brake cylinder air. To apply the brake the handle 
 4 is moved to the right. With valve 8 moved down off its 
 seat, main reservoir air in a passes through b, b 1 and b- 
 — see Fig. 3 — and out at x — see Fig. 2 — through the pip- 
 ing leading to the Double Check valves and cylinders. 
 Exhaust valve 9 at this time is on its seat as shown in 
 Fig. 2, so that no air can pass out through c to the 
 exhaust. To release the brake the handle 4 is moved to 
 the left, which allows main reservoir air valve 8 to close 
 
 r\ 
 
 r\ 
 
 Fid. FlG -«- 
 
 Straight-Air Brake Valvb, 
 
102 DOUBLE CHECK VALVE 
 
 and then open exhaust valve 9, so that air in the cylinders 
 can pass out to the atmosphere. When handle 4 is in 
 mid-position, both valves are closed so that they are. 
 "on lap." 
 
 A leather washer 6 prevents leakage from b to the 
 atmosphere when the brake is applied; spring 7 holds 
 shaft 2 against this washer when there is no compressed 
 air in this part of the valve — see Fig. 3. 
 
 To regulate the pressure of the air fed from the main 
 reservoir to this valve, a G-6 Slide Valve Feed Valve is 
 used, located on the pipe between the reservoir and brake 
 valve and set to close at 45 pounds. This reducing valve 
 regulates the brake cylinder pressure to the proper amount, 
 and also restricts the flow of air and assists the engineer 
 in making moderate applications. 
 
 The Double Check Valve shown in Fig. 4 is located in 
 the pipe between the triple valve and the cylinders, in a 
 horizontal position so that it will not open or close by 
 gravity. The triple valve is coupled to one end-, the 
 straight air brake valve at the other. The brake cylinder 
 can be coupled to either side, as shown, one side can be 
 used for the safety valve, or a driver brake cylinder can 
 be coupled to each side and the safety valve located in the 
 pipe leading to the cylinder. Two of these valves are 
 required, one on the engine and one on the tender, with 
 a ?4-inch pipe connecting them to the straight air brake 
 valve, the same as the 1-inch brake pipe connects the 
 triple valve and automatic brake valve. 
 
 Two safety valves are required, one for the engine and 
 one for the tender, set at 53 pounds. 
 
 When the straight air is used it moves valve 5, Fig. 4, 
 over so gasket 7 makes a tight joint at b and the air 
 passes through opening c to the cylinders, but cannot get 
 to the exhaust port of triple valve. If automatic is applied, 
 air from the triple valve moves valve 5 so the opposite 
 gasket makes a joint at a and air passes through ports 
 c 1 to the cylinders, but cannot pass to the straight air 
 brake valve. Thus you see the double check valves auto- 
 matically connect the brake cylinders to either the auto- 
 
DOUBLE CHECK VALVE 
 
 103 
 
 matic or straight air system and prevent air passing out 
 of the exhaust port of one system while the other is 
 being operated. 
 
 When operating the straight air, move handle 4 over 
 and you will feel the resistance of valve S ; a little practice 
 will enable you to calculate the amount of air you allow to 
 pass into the cylinders in a partial application; you can 
 
 Fig. 3. 
 
104 OPERATING STRAIGHT AIR BRAKE 
 
 follow up by admitting additional amounts of air, till if 
 necessary, the brake is fully applied, of course, taking care 
 not to shock the cars attached to the engine by too sud- 
 den an application. If it is to be held fully applied leave 
 the valve in application position, so as to feed up any 
 leaks that may reduce the power. For a full, quick appli- 
 cation the valve may be opened wide, as the reducing 
 valve will stop the flow of air from the main reservoir 
 when it reaches the pressure at which the reducing valve 
 is set. A partial release can be obtained by opening and 
 closing the valve 9 ; a quick, full release by moving 
 handle 4 to exhaust position and holding valve 9 open. 
 
 If the straight air brake is left on lap while the auto- 
 matic is applied, when the automatic is released the double 
 check valve may be shifted by the pressure of the air that 
 may get in the pipe between the check and the straight 
 air valve, if the check valve shifts and closes the opening 
 at b the brake cylinder air cannot get out of exhaust port 
 of triple, and thus cause the driver and tender brakes to 
 stick. A new style of double check valve now in service 
 prevents this trouble. When using automatic, handle 4 
 should always be in full release position, holding valve 9 
 open. The automatic brake valve when not in use should 
 be on running position and at least 10 pounds excess 
 carried to prevent triple valves "creeping on" at any time. 
 
 Never apply both brakes at once while switching. 
 When you use automatic be sure the other is in release 
 position first. If necessary to use straight air on top of 
 the automatic to hold the slack of train, when the auto- 
 matic is to be released, remember that a movement of 
 both valves to release is necessary to let off the locomotive 
 brake. 
 
 If wheels skid on a good rail, test the safety valves and 
 the reducing valve; they should relieve any over pressure, 
 whether from a reducing valve allowing too high a press- 
 ure, or from a double application, that is, an application 
 with the automatic while the straight air is still applied; 
 this will give a higher pressure than if the automatic 
 
STRAIGHT AIR BRAKE PRESSURE 105 
 
 has set full first and is almost sure to slide wheels ; there- 
 fore must not be used. Straight air gives 45 pounds only 
 in the cylinders at any time ; if the automatic is applied on 
 top of this 45 pounds, the 70 pounds in the auxiliary will 
 tend to raise the cylinder pressure close to 65 pounds. The 
 safety valves should reduce it down to 53 pounds. 
 
 Both safety valves and the feed valve should be tested 
 at regular intervals with a gage to insure that they 
 regulate the pressure properly. There should be Tees so 
 located in the pipes that a gage can be readily attached 
 for this purpose. 
 
 39. Q. How should the automatic brake valve be 
 carried when backing up the train, or when expecting the 
 trainmen to set brake from rear end? 
 
 A. On running position ; so the brake will be applied 
 as soon as brake pipe pressure is reduced, when brake 
 valve should be placed on lap at once. This also applies 
 to pushing a snow plow if brake is handled from the plow. 
 A few companies require that the brake valve be kept on 
 running position all the time, when backing up a train. 
 There is some difference of opinion as to the proper posi- 
 tion of the H-5 valve, some carry it on holding position 
 and use the independent valve to release the locomotive 
 brake. The H-6 valve can be carried in running position. 
 
 40. Q. How do you set and release the automatic 
 brake? 
 
 A. Reducing the brake pipe pressure operates the triple 
 valve to apply the brake and restoring the original press- 
 ure releases it ; this is the engineer's method. It can be 
 applied from the train by opening the conductor's valve, or 
 the angle cock at the rear of last air brake car. Pulling 
 the hose apart at the couplings, a hose bursting or any 
 bad leak or break in the brake pipe will set the brake. 
 When the train breaks in two between air cars all air 
 brakes on both parts of the train that are cut in set 
 instantly. A brake can be set on a car that is alone by 
 opening the angle cock to let air out of the brake pipe. 
 In such a case the brake can be released by bleeding the 
 
106 GRADUATED APPLICATION 
 
 auxiliary reservoir. If a brake is to be released from the 
 train the auxiliary pressure is reduced by bleeding till it 
 is lower than the brake pipe so the triple valve will open 
 the exhaust port, or all the air is bled out of both reser- 
 voir and brake cylinder. Usually the release spring in 
 the brake cylinder will push the brake piston back over 
 the leakage groove before the graduating spring moves 
 the triple piston and slide valve to lap. 
 
 41. Q. Can a gradual application of the brake be 
 made, that is, with only part of its full force? 
 
 A. Yes, by reducing the brake pipe pressure only a 
 few pounds, say five to seven pounds for first reduction; 
 this reduction is necessary to make brake piston move over 
 leakage groove; a lighter reduction than five pounds will 
 not always do this ; two to three pounds at each of the 
 succeeding reductions, less than twenty pounds in all. 
 
 42. Q. Why does this reduction of only a few pounds 
 in the brake pipe pressure make a light application of the 
 brake ? 
 
 A. With a light reduction the triple piston moves 
 down slowly, opening the air valve slowly; the air from 
 the auxiliary reservoir passes into brake cylinder through 
 graduating valve and a small port in the slide valve; as 
 soon as the auxiliary pressure is a little lower than brake 
 pipe pressure, the brake pipe pressure raises the piston, 
 closing the graduating valve so no more air can pass into 
 brake cylinder, thus setting the brake lightly. To illus- 
 trate this, we will let out seven pounds of air, reducing 
 brake pipe pressure from 70 to 63 pounds, that leaves 70 
 pounds above triple piston, which moves the triple piston 
 down towards the lower pressure, opening graduating 
 valve 7 first; then moving slide valve 3 so that air can 
 pass through it; when enough air has gone into the 
 cylinder to reduce the auxiliary pressure below 63 pounds, 
 the brake pipe pressure moves the piston towards the 
 lower auxiliary pressure, closing graduating valve; 
 another reduction produces the same effect, each time 
 setting brake tighter till pressures equalize. The piston 
 
FULL SERVICE APPLICATION 107 
 
 moves the main slide valve at the first reduction, but only- 
 opens and closes the graduating valve at the following 
 reductions till a full application is made. 
 
 43. Q. How much do you reduce the brake pipe press- 
 ure to make a full service application of the brake if the 
 piston travels are the proper length? Why does a reduc- 
 tion of twenty pounds set the brake "full on?" 
 
 A. About 20 pounds, or from 70 pounds down to 50, 
 or until the auxiliary pressure has equalized with brake 
 cylinder. 
 
 If the brake is in good order, with a piston travel 
 of eight inches, a reservoir pressure of 70 pounds will 
 fill the brake cylinder and equalize in both at 50 pounds, 
 that will leave 50 pounds on top of triple piston. If the 
 pressure on the brake pipe side or under the triple piston 
 is any less than 50 pounds, the piston will stay down and 
 hold the air valve open and pressures must equalize. 
 One pound less will hold it down as well as any amount. 
 When it has equalized, no more air will pass from aux- 
 iliary to brake cylinder, pressure on brake piston will not 
 rise above 50 pounds, and brake cannot be set tighter. 
 Any reduction of brake pipe pressure that leaves it lower 
 than auxiliary pressure will set the brake tight. If a re- 
 duction of £0 pounds opens the air valve and holds it 
 open, any further reduction will not produce any effect on 
 it, and so far as that brake is concerned is only a waste of 
 air, which must be supplied from main reservoir when 
 you want to release brake. If any check valves in quick- 
 action triples leak, a reduction in brake pipe pressure 
 below brake cylinder pressure will let the brake leak off 
 through this check into brake pipe. 
 
 44. Q. What is necessary to have brakes set alike, 
 with same reduction of brake pipe pressure and release at 
 same time, with same increase of brake pipe pressure? 
 
 A. 1st. The auxiliary pressures must all be the same 
 to move triples down towards the same reduced brake 
 pipe pressure. For example, if one auxiliary has 70 
 pounds, another 60, a reduction of brake pipe pressure 
 
108 QUICK-ACTION TRIPLE 
 
 below 70 will set the first brake, but it takes a reduction 
 of below 60 to set the other one. 2d. All piston travels 
 must be the same, for with a 20 pound reduction a short 
 travel equalizes at a less reduction with a higher pressure 
 than a long travel. When brake pipe pressure is increased, 
 triple controlling brake with long travel will release first 
 as the auxiliary pressure is lowest. Thus, brake with 
 long travel equalizes last with lowest piston pressure and 
 lets go first. 3d. That all triples and brake pistons are 
 in good order and no leaks. 4th. That the main reser- 
 voir pressure and volume are sufficient to move all triples 
 to release quickly. 
 
 45. Q. What is the difference between the plain engine 
 triple valve and the car or quick-action triple? Why will 
 not the plain triple do as well on a long train? 
 
 A. A plain triple gets all its supply of air to set the 
 brake from the auxiliary reservoir only; the quick-action 
 triple gets it all from the auxiliary on a service applica- 
 tion; when used with emergency it gets air from both 
 train pipe and auxiliary. With a long train equipped with 
 plain triples it takes some seconds to reduce the brake 
 pipe pressure at last car and operate the last triple; the 
 pressure in brake pipe is reduced slowly on last cars, 
 which makes them set gradually; the brake pipe reduction 
 is made at the engine only. The quick action triple has 
 two separate actions; in one a service application operates 
 only the plain part of it; in the other, plain and quick 
 action parts are operated at once. A quick action triple is 
 not always needed on an engine or tender, as they are so 
 close to the brake valve that they operate quickly enough. 
 In an emergency application the quick-action triple allows 
 some of the brake pipe air to escape at the triple so that 
 the brake pipe pressure is suddenly reduced at this triple; 
 this also operates the next triple quick-action, which re- 
 duces the brake pipe pressure still more, so that all the 
 triples act quicker than when the reduction is made at 
 the brake valve, and all the brakes are set at nearly the 
 same instant. Thus there is less shock to the rear cars 
 
EMERGENCY APPLICATION 109 
 
 of a full air brake train, as the action of the triples 
 travels from one to the other faster than the slack can 
 run up from car to car. 
 
 46. Q. What is the emergency or quick application? 
 
 A. If the brake pipe pressure is suddenly reduced at 
 the first application 10 pounds or more, at the quick- 
 action triple, so the graduating valve cannot reduce the 
 auxiliary pressure at the same rate, auxiliary pressure 
 will move piston by the service position, the emergency 
 part of the triple valve is brought into action, opening a 
 large port in the triple so the air goes from the brake 
 pipe direct into the brake cylinder, not only setting the 
 brake quick-action, but also reducing the brake pipe 
 pressure suddenly at that point, instead of all the air 
 having to go clear to brake valve to escape and reduce 
 pressure. This sudden reduction sets the next triple in 
 the same manner, which sets the next one, and so on to 
 the last car; its action from one car to another is so quick 
 that even on a long train it seems to catch all at once. 
 When a quick-action triple takes air from the brake pipe 
 and sets the next triple quick-action, • it also takes air 
 from its auxiliary through a small port ¥j after the brake 
 pipe has equalized, so the full application is made at 60 
 pounds, about 10 pounds more than the piston pressure 
 in full service application. 
 
 If at the head end of train there are four cars with 
 the triples, cut out at the cross-over cocks ; or four cars 
 with brake pipe only, the reduction of brake pipe pressure 
 at the fifth car will be so gradual that it will not work 
 quick-action ; it takes a sudden reduction right at the 
 triple to get the quick action. W^hen there are only two 
 or three cars behind these cut-out triples, the small volume 
 of their brake pipe will assist in having the quick-action 
 jump over the cut out ones. At the rear end more than 
 four cars can be cut out and get the quick-action as the 
 ''dead end" of the brake pipe will help to make a sudden 
 reduction on the last cars. 
 
 A sudden reduction of brake pipe pressure which will 
 
110 
 
 EMERGENCY APPLICATION 
 
 pull the triple piston down hard enough to compress the 
 graduating spring and let piston make a full travel will 
 open the large air port in plain triple valve, so brake will 
 set somewhat quicker, but does not set with any higher 
 piston pressure. 
 
 47. Q. Explain the operation of the quick-action triple 
 when used on the "emergency." 
 
 A. A sudden reduction in the brake pipe pressure 
 right at the triple must be made, so the triple piston will 
 make a full stroke and open the emergency port in seat 
 
 This cut shows the quick-action 
 
 triple in emergency position. Port t 
 
 registers with the notch in side of 
 
 slide valve or the "removed corner" 
 
 of slide valve, which is not shown in 
 
 cut. Auxiliary air passes through 
 
 this notch under port z into t on emergency 
 
 piston 8. Poits z and t are beside each other, 
 
 but no air passes from port z into /. 
 
 QUICK -ACTION TRIPLE VAI<VE— EMERGENCY POSITION. 
 
EMERGENCY APPLICATION 111 
 
 under slide valve, which will admit the auxiliary pressure 
 over the emergency piston 8. This in turn pushes the 
 emergency or rubber-seated valve 10 off its seat, and the 
 brake pipe air can then go direct to brake cylinder through 
 large port C, raising the brake pipe check valve 15 to do 
 this. As soon as the brake pipe and brake cylinder press- 
 ures have equalized, the check 15 seats itself, and a spring 
 in this check valve pushes the rubber-seated valve 10 up 
 against its seat as soon as the auxiliary and brake cylinder 
 pressures are nearly equalized. At the same time that 
 brake pipe air is passing into the cylinder, the air from 
 the auxiliary is also going through a small port in the 
 end of slide valve 3. This port is made very small to 
 give the brake pipe air a chance to equalize into the brake 
 cylinder first, then the auxiliary pressure equalizes with 
 the brake cylinder afterwards, at about 60 pounds. The 
 emergency valve 10 is used to hold the brake pipe air 
 out of the brake cylinder, therefore in quick-action it 
 must be moved off its seat against the brake pipe press- 
 ure; this is done only when triple piston makes a full 
 stroke suddenly. If it moves down slowly, the graduating 
 valve will allow air to pass from auxiliary into brake 
 cylinder before emergency port is opened, and reduce 
 the auxiliary pressure as fast as the brake pipe pressure 
 falls, so graduating spring will have power to prevent a 
 full stroke of piston. 
 
 48. Q. Can you get the emergency action of the quick- 
 action triple while brakes are set with a service applica- 
 tion? 
 
 A. Not unless they are set with a light application. 
 The pressure in auxiliary and brake pipe must be con- 
 siderably higher than in the brake cylindejr, or the 
 emergency piston will not move valve 10 off its seat, 
 nor will check 15 raise to allow air to pass through. 
 Then, if a partial service application has been made, the 
 graduating valve can open first, which reduces the aux- 
 iliary pressure some and retards the full stroke of the 
 piston a little in opening the emergency port. Even if 
 
112 EMERGENCY APPLICATION 
 
 all these emergency valves operate after a moderate 
 service application, only a very little air will pass through 
 them, not enough to affect the triples behind it, or raise 
 the pressure in cylinder very much. See Q. 111. 
 
 49. Q. Is it practicable to attempt to get the emer- 
 gency action of the brake by suddenly recharging the 
 hvakt pipe for one or two seconds and then opening the 
 direct application port wide? 
 
 A. No. The triple piston will not move till you have 
 reduced the brake pipe pressure a little lower than the 
 auxiliary pressure, and no air can pass into the brake 
 cylinder from either brake pipe or the auxiliary till piston 
 moves and opens the valves. By this movement you will 
 partially release some of the brakes and may get a lighter 
 service application the second time than you had at first. 
 Don't try it. Unless you have time to recharge auxiliaries 
 to 70 pounds, hang on to what you have. 
 
 50. Q. Is it safe to try and retain air in a brake pipe 
 in the emergency application, and why not? 
 
 A. It is not safe as a general rule. In an emergency 
 when life or property are in danger, you must act quickly, 
 The point is to get stopped dead as soon as possible, and 
 see about getting started afterwards. An emergency appli- 
 cation is the last resort and you must get it when you 
 need it. If you do not let nearly all the air out of a long 
 b>rake pipe, some of the triples will not act quick enough. 
 If three or four triples are cut out, or there are three or 
 four plain triples close together at the head end of the 
 train, the quick-action will not catch behind them and 
 all the air must be let out at head end of train to reduce 
 the pressure as quickly as possible. A full reduction of 
 "20 pounds is necessary to set the plain triples on engine 
 and tender so these brakes will do their full share. With 
 a double header it is generally necessary to let the air 
 out at brake valve of rear engine to catch the quick- 
 action on the train. With a full train of quick-action 
 triples a sudden reduction of 25 or 30 pounds at the 
 •engine will catch them all and leave considerable air in 
 
QUICK- ACTION TRIPLE DEFECTS 113: 
 
 the brake pipe, so you can release and back up out of 
 the other train's way if the brake stops you in time. This 
 is the only special exception to the general rule. It is 
 easy to hold part of the air when making tests or in the 
 instruction car; but when you think some one is going 
 to get killed, it is not quite as easy as clear over to full 
 emergency. 
 
 51. Q. How does the quick-action triple operate on a 
 short train, if graduating pin is broken? Or .the graduat- 
 ing ports gummed up? 
 
 A. With the emergency on a light service application. 
 If the graduating pin is broken, the graduating valve will 
 be held on its seat by auxiliary pressure, and the emer- 
 gency port is the first one to open. 
 
 If the graduating valve is gummed up or dirty so the 
 air can not flow past it properly, the triple will work with 
 emergency when you make a moderate service application. 
 With a long train the emergency port is opened so gradu- 
 ally that the air can get past the emergency piston and go 
 to the cylinder without moving the emergency piston. 
 
 52. Q. If while making a moderate service applica- 
 tion your brakes would "fly on" and at the same time the 
 air would stop running for a moment from brake pipe 
 exhaust and then begin again, where would you look for 
 the trouble? 
 
 A. In one of the quick-action triples. This action of 
 the brake valve shows that one of the triples is working 
 quick-action only, in advance of the rest, even with a 
 service application. - When the triple works quick-action, 
 it takes some air from the brake pipe, reducing the press- 
 ure so the equalizing piston seats for an instant. At the 
 same time the black hand takes a sudden drop for an 
 instant. Probably the graduating pin is broken, although 
 a broken graduating pin in service is very rare. If the 
 graduating spring 22 has been left out it is very apt to 
 cause quick-action. If the triple piston or slide valve is 
 gritty or badly gummed so it does not move freely, it will 
 cause this trouble. 
 
114 QUICK-ACTION TRIPLE DEFECTS 
 
 If the graduating valve or its ports are gummed up so 
 that the air cannot flow past it out of auxiliary to equalize 
 the pressures as fast as it flows out of brake pipe, this 
 triple will be sure to work quick action. A quick-action 
 triple that needs cleaning, or has the graduating ports 
 defective in any way, is liable to work quick-action with 
 a moderate service reduction. If the brake pipe exhaust 
 elbow is gone from the brake valve it will allow so 
 sudden reduction of brake pipe pressure that the triples 
 will work quick-action on a very short train. 
 
 Improper handling of the brake valve will also cause 
 triple valves to go into quick action with a service re- 
 duction. With a very long train it takes quite a few 
 seconds to have the reduction made at the brake valve 
 felt on the rear car. If you have overcharged the head 
 end by full release position for fifteen or twenty seconds 
 and then begin a service application, air is still feeding 
 into the rear triples; this makes a reduction at the rear 
 end and the brake valve one on the head end, the triples 
 ahead of the middle of the train cannot keep up and 
 •go into quick action. 
 
 To locate one of these defective triples, close some of 
 the angle cocks so as to use not over ten cars at a time, 
 and make a moderate reduction, say five pounds, then 
 make another of five more. If the brakes work quick- 
 action you can be certain the defective triple is on one of 
 these cars. After recharging, set the brake again with 
 about seven pounds reduction, and note which brake has 
 not set at all. Cut this one out and make another test, 
 which will show if you have the right one. If you do 
 not find it in the first set of ten cars tried, cut in some 
 more and try them. The disabled triple will not always 
 set at the first reduction, and will work quick-action at 
 the second one ; it is more apt to give trouble in a short 
 train than in a long one. 
 
 53. Q. If with a quick-action triple, the brake should 
 refuse to release, but kept blowing from the exhaust port 
 
QUICK-ACTION TRIPLE DEFECTS 115 
 
 or pressure retainer, what would be the matter and what 
 would you do? 
 
 A. The emergency valve 10 was likely held off" its 
 seat or was worn out and leaked badly. If out on the 
 road and valve would not quit leaking after a few emer- 
 gency applications, would cut out that brake. If the 
 gasket between the triple valve and cylinder head on a 
 passenger brake or next the reservoir on a freight brake 
 had blown out, it would let auxiliary reservoir air into 
 exhaust and the blow would soon be down to the capacity 
 of the feed port in triple valve. A small leak past the 
 emergency valve when the brake is set will soon equalize 
 the brake cylinder and brake pipe pressures. With a 
 sticky triple this brake might not release with increase of 
 brake pipe pressure and wheels be skidded. Better cut 
 out such a brake and bleed it. 
 
 54. Q. Describe tthe construction and operation of the 
 Quick Service Triple Valve, Type K. 
 
 A. The quick service triple valve shown in the next 
 illustration is similar to the ordinary quick-action triple 
 in use for many years, but has some additional features. 
 There is an additional air port y leading from the 
 chamber Y between the brake, pipe check 12 and the 
 emergency valve 10, up through the triple body to the 
 slide valve bushing at c. This port c is covered by the 
 slide valve so any air passing through port c must also 
 pass through a port in the slide valve to get any farther. 
 The graduating valve 7 is a small flat valve with a cavity 
 v in its face, this valve rides on the back of the slide valve 
 3 and moves each time piston 4 does. There is some lost 
 motion between the shoulders of the piston stem and the 
 ends of slide valve 3, so the piston can move this distance 
 without moving valve 3, this allows the piston to move 
 and close the feed port i as well as open and close the 
 ports under the graduating valve without moving slide 
 valve 3. On the reservoir end of the triple is attached a 
 cage 29, containing a "retarded release" stem 31 and its 
 spring 33. The later type of K triple is shown here, and 
 
116 
 
 K TYPE TRIPLE VALVE 
 
 below the triple is shown the first style of release stem 
 and spring. A small pin 34 prevents stem 31 moving 
 too far in the cage when taken off. There was no feed 
 groove in the shoulder of piston 4 where it rests against 
 the slide valve bushing when at its extreme travel in 
 release position in the first K triples, so that in this posi- 
 tion, air passing through feed port i could not get into 
 the auxiliary. The later ones have a groove in this 
 shoulder. When the piston and slide valve are in free 
 release position the stem 31 and spring 33 are in normal 
 position — not compressed — the exhaust port in slide valve 
 3 is wide open and the feed ports open so brake pipe air 
 can equalize to the auxiliary. In the triples used with 
 10-inch brakes and larger ones, there is also a feed port 
 
 7 35 3 6 A 5 
 
 TO AUXILIARY 
 RESERVOIR 
 
 12 26 
 
OPERATION OF K TRIPLE 117 
 
 through the slide valve that is open in free release. There 
 is a small feed port through the slide valve that is open 
 only in retarded release position which charges the aux- 
 iliary very slowly. The feed port i around the piston 
 is the same size in all quick-service triples, so most of 
 the air in the large triples passes through the feed port 
 through the slide valve. After the auxiliary has charged 
 to standard pressure, which we will assume is 70 pounds, 
 a moderate brake pipe reduction will move the piston 4 
 to the right following the reduction. This movement first 
 closes feed port i and moves the graduating valve 7 on 
 the back of the slide valve 3 to close feed port and open 
 the supply ports under it. The slide valve then moves, 
 first closing the exhaust port and next opens the service 
 ports in valve 3 to the ports in its seat. Auxiliary air 
 then flows to the cylinder through port r. At the same 
 time brake pipe air from chamber Y flows through port 
 y, a port through slide valve 3, the cavity of the graduat- 
 ing valve 7 and ports in slide valve 3 into port t in the 
 seat, and thence around the emergency piston — which is 
 not an air tight fit— into X and the cylinder. This small 
 amount of brake pipe air passing to the cylinder is not 
 sufficient to cause an emergency reduction, but causes the 
 next triple to operate more certainly and thus applies 
 all brakes in a train in less time than when the entire 
 brake pipe reduction is made at the brake valve. The 
 brake pipe air passing to the cylinder in a service applica- 
 tion increases the pressure there so that a five-pound 
 reduction in brake pipe and auxiliary will give about 
 14 pounds in the cylinder as well as applying the quick- 
 service triples in less time from front to rear of train. 
 The air from the brake pipe also tends to give a higher 
 pressure with long piston travel than with the old triples 
 taking air from the auxiliary only. 
 
 On account of the arrangement and size of the service 
 ports the quick-service triples are not as liable to go into 
 undesired quick action as the older form. When in quick- 
 service position the ports are only open a portion of their 
 
118 OPERATION OF K TRIPLE 
 
 full size to reduce the auxiliary pressure as fast as brake 
 pipe pressure is ordinarily reduced at the brake valve. If 
 the triple piston moves over enough to compress the 
 graduating spring 22 a little, the service ports will open 
 wide; this reduces auxiliary pressure so fast that the 
 piston will not go to emergency position for a moderate 
 reduction unless it is defective. When the brake valve is 
 placed in full release and the brake pipe at the head of 
 the train charged much higher than the auxiliary press- 
 ures there, the quick-service triples there will move past 
 free release position compressing the stem 31 and spring 
 33 and the slide valve exhaust cavity will be moved far 
 enough so the wide open port of this cavity will be 
 beyond the exhaust port and the small part of the exhaust 
 cavity will be in register with the port. This causes the 
 air to exhaust from the brake cylinder very slowly and 
 the quick-service triples at the head end that have the 
 high brake pipe pressure hold their brakes set some 
 seconds longer than when in free release position. As 
 the brake pipe pressure reduces farther back in the train 
 until it is not enough higher than the auxiliary to move 
 the triple piston to retarded release position against the 
 resistance of spring 33, the triples will all move to free 
 release position as fast as the increase of brake pipe 
 pressure reaches them. On a fifty-car train equipped with 
 the quick-service triples, about one-third of them, or 
 fifteen to twenty will go to retarded release and those 
 next will release quickly. This tends to release the 
 middle and rear cars of a long train before the cars next 
 the engine are fully released, as the head brakes are 
 retarded, the whole train will release at about the same 
 time, and thus prevent the slack running out and break- 
 ing trains in two or more parts when releasing brakes at 
 a slow speed. To get the retarded exhaust of quick-service 
 triples when the entire train is not equipped with them, 
 these triples should be next the engine. When at the 
 rear they do not retard the release any more than the 
 ordinary quick-action triple. 
 
TYPE L TRIPLE VALVE 119 
 
 55. Q. Describe the Westinghouse Type L Triple 
 Valve. 
 
 A. The Westinghouse L triple valve is designed for 
 high duty passenger service, it is pipeless, that is, all air 
 pipe connections are made at the pressure head to which 
 the triple is bolted; it uses two reservoirs; one the 
 ordinary size for that brake cylinder and a supplementary 
 reservoir about twice the volume of the service auxiliary. 
 In case this supplementary is not to be used when other 
 cars in the train do not have it, a cock cuts it out from 
 the triple valve, this cuts out the graduated release 
 feature and the very high pressure with quick action. The 
 L triple is a quick-service and a quick-action valve, the 
 quick-service feature has been explained in connection 
 with the K triple, and the quick-action also, we need not 
 repeat all of it here, and it is understood that the student 
 is familiar with the action of the ordinary quick-action 
 triple. This triple does not have the retarded release 
 through a small exhaust cavity that the K triple has, 
 therefore does not use a retarded release spring, the ex- 
 haust cavity is in the graduating valve, and is of the 
 proper size to exhaust the brake cylinder air in the 
 standard time. The exhaust valve is under control of 
 the engineer, who by changes in the brake pipe pressure 
 and the aid of the supplementary reservoir, can allow all 
 the brake cylinder air to pass out freely, or hold it back 
 and reduce the cylinder pressure a little at a time till 
 down to nothing; by the control of the exhaust you can 
 have a moderate cylinder pressure at the instant the stop 
 is made. 
 
 Two sectional views of the actual valve, a side eleva- 
 tion and an end elevation and a diagrammatic view of 
 the valve in full release and charging position are shown. 
 
 In release position, or when running between stations 
 both reservoirs charge at the same time and to the same 
 pressure through the L triple. There is the usual feed 
 groove i in the cylinder bushing to allow air from the 
 brake pipe to pass around the triple piston; it is a small 
 
120 
 
 TYPE L TRIPLE VALVE 
 
 3» 26 25 27 20 29 30 
 
 FULL RELEASE AND CHARGING POSITION. 
 
 one, more to keep the brake pipe and auxiliaries equalized 
 after charging than to do much of that work. There is 
 a charging port / through the slide valve; open in release 
 position only, that connects with cavity Y above the 
 brake pipe check 15 ; air can pass by check 15 and go 
 through the slide valve 3 to the reservoirs, but check 15 
 prevents it getting back to the brake pipe during a reduc- 
 tion. When a service application begins, this charging 
 port in slide valve 3 is first closed as well as the port k 
 leading to the supplementary through x, so no air can get 
 
OPERATION OF L TRIPLE 121 
 
 out of there, air from the service auxiliary only is used 
 in a service application, supplementary air remains bottled 
 up till the triple goes to release position, when this large 
 volume of air at standard pressure will quickly equalize 
 with the service auxiliary at close to the standard press- 
 ure, even before the brake cylinder air has escaped; this 
 makes a quick recharge from the supplementary to the 
 service auxiliary. If 90 pounds is carried, after a full 
 service application the service auxiliary will have 70 
 pounds, and the 90 pounds in the supplementary will 
 equalize in both of them at over 83 pounds, air from the 
 brake pipe will soon put the other 6 pounds in, 
 
 Referring to the diagrammatic view, all the air ports, 
 passages and cavities in the valve and seat are shown ; 
 something that cannot be done in the view of the actual 
 valve as many of the ports cannot be made to show in a 
 correct sectional view. Air from the brake pipe enters 
 at the lowest passage through a, e and g to h, forces the 
 triple piston 4 to release and charging position, if not 
 already there, and passes around the triple piston, through 
 port i into R and the auxiliary reservoir. Air also passes 
 through port k in slide valve 3 and x to the supplementary 
 so it charges at the same time as the service auxiliary. 
 Brake pipe air raises check 15 and goes through port r 
 in the body of the valve and its seat, thence through port 
 I in slide valve 3 to R, so air is passing into R from two 
 sources. Port / is larger in the large triples than in the 
 small ones, but feed-groove i is the same size in all of 
 them. Any air that may be in the brake cylinder will 
 pass through C, r, n, in valve 3, then through cavity w in 
 graduating valve 7 into port m, and finally into P, the 
 final exhaust. You will note that exhaust air must pass 
 through a cavity in graduating valve 7, this will explain 
 why a movement of the graduating valve will open and 
 close the exhaust, t is the emergency port through which 
 auxiliary air passes in over piston 8 when slide valve 3 
 is back in emergency position. There are two pistons in 
 this triple that operate only in an emergency application, 
 
122 OPERATION OF L TRIPLE 
 
 piston 8 that does the same work as piston 8 in the 
 ordinary quick-action triple and piston 25, called the by- 
 pass piston, its duty is to open by-pass valve 27 to allow 
 air in the supplementary to equalize with the service 
 auxiliary in an emergency application. This piston is 
 shown at the top in the actual triple. During a service 
 application the auxiliary pressure remains equalized on 
 both sides of piston 25 so it does not move. In an 
 emergency application slide valve 3 moves back far 
 enough so port c registers with d in the slide valve, this 
 opens a communication between f on the inside of piston 
 25, through c, d, m and r to the brake cylinder; auxiliary 
 pressure in B forces it over and opens valve 27; 
 this allows supplementary air to flow to the auxiliary 
 and equalize at very nearly the standard auxiliary press- 
 ure. If, at a service application, an emergency arises, a 
 sudden reduction of brake pipe pressure at the brake 
 valve will put the L triples into the emergency position, 
 the by-pass valve will be opened and the supplementary 
 air will pass into the brake cylinder and service auxiliary 
 giving a high braking pressure, which the safety valve 
 will hold till released the regular way. Port b connects 
 with safety valve 33 in release and all service positions 
 so the safety valve can blow down cylinder pressure to 
 its adjustment at ordinarily 62 pounds. In an emergency 
 application cavity q travels past port r so the brake 
 cylinder is cut off from the safety valve and there is no 
 escape of air at the safety valve in an emergency applica- 
 tion, all the air is held in the cylinder till the brake is 
 released the regular way. 
 
 In a graduated service application there are two posi- 
 tions of piston 4 and slide valve 3, the first one is quick- 
 service position; in this, port o in valve 3 is brought in 
 register with port 3/ in the seat, so air passing check 15 
 can flow through y and 0, graduating valve 7 being moved 
 back at that time air from will pass through the small 
 cavity v in graduating valve 7, through the small port 
 into cavity q and thence to C and the brake cylinder, this 
 
OPERATION OF L TRIPLE 123 
 
 makes a gradual brake pipe reduction at the triple and 
 starts the other triples in the rear of it, to service position 
 quicker than the brake valve reduction would. Port z 
 in slide valve 3 has been brought in register with r in 
 the seat, graduating valve 7 having uncovered z at the 
 top, auxiliary air also flows to the cylinder at the same 
 time air from the brake pipe passes in. As soon as the 
 auxiliary pressure is a little lower than that of the brake 
 pipe and the reduction at the brake valve is stopped, the 
 auxiliary reduction gets ahead of that in the brake pipe 
 at h so piston 4 moves towards the right carrying with it 
 valve 7 closing ports z and the small port into q, this 
 stops the flow of air into the cylinder and holds it there. 
 Another gradual reduction at the brake valve produces 
 the same effect, till the pressures are equalized between 
 the auxiliary and brake cylinders. 
 
 If the train is a short one the piston and slide valve 
 pass by the quick-service position to what is called full 
 service position in which port o in valve 3 moves pasi 
 port 3; in the seat so no air passes that way and port 3 
 is opened full width to r, this takes auxiliary air to 
 cylinder faster than in the quick-service position and 
 tends to prevent the triple going into quick action on a 
 short train. In quick-service position knob J on piston 
 4 touches the graduating stop 21 without compressing 
 it, in the full-service position it compresses the spring a 
 little till its resistance will stop piston 4, this also aids in 
 preventing quick-action applications with a service re- 
 duction. It is the graduated or "step-down" release that 
 requires the most study to understand. During a brake 
 application the supplementary still holds the standard 
 pressure we had at the beginning of the application. 
 When the triple piston 4 and the slide valve 3 move to 
 the right at the release, exhaust port n is in register with 
 r in the seat, cavity w in valve 7 allows air from the 
 cylinder to pass out through m to P. At the same time 
 port k in the slide valve is in register with x in the seat, 
 so supplementary air feeds into R and the service aux- 
 
124 GRADUATED RELEASE 
 
 iliary. If the brake pipe pressure in h has been raised by 
 the brake valve being left in full release so it is higher 
 than the supplementary can equalize with R, piston 4 
 will remain in rull release. But if the brake pipe pressure 
 is raised a few pounds and the brake valve lapped, as soon 
 as the supplementary air coming through port k can 
 raise the pressure in R higher than the brake pipe press- 
 ure in h, piston 4 will move back carrying graduating 
 valve 7 with it, closing port k so the pressure in R will 
 not rise any higher and closing port m so no more air 
 can pass to the exhaust from the cylinder, this allows 
 part of the cylinder air to escape, how much, depends on 
 how long the exhaust cavity w connects ports n and m. 
 Valve 3 is not moved, as the raise in pressure in R is 
 only sufficient to move piston 4 and valve 7, when port 
 k is closed and stops the rise in pressure. Another re- 
 charge of the brake pipe and lapping the brake valve will 
 move piston 4 and valve 7 so ports k and m will be 
 opened and more air will exhaust from the cylinders, 
 these recharges at the brake valve and exhausts at the 
 triple will continue until all the air has escaped from 
 the cylinder. After slide valve 3 has moved to release, it 
 is a movement back and forth of the graduating valve 
 that opens and closes exhaust port m, supplementary 
 port k and brake pipe port j. The older makes of triples 
 have the exhaust cavity in slide valve 3, the L triple has 
 the exhaust cavity in graduating valve 7. This explana- 
 tion and the illustrations will give a good idea of how 
 to operate this triple, so we will not speak further of its 
 operation. 
 
 This type of triple valve is being modified and im- 
 proved from time to time so we may expect it to do still 
 more in the future than it does now. 
 
 56. Q. How do you locate a leak that lets off the 
 brake ? 
 
 A. If it leaks off through piston packing leather the 
 air will blow out of the hole in spring case or lower head 
 in push down brake; with a pull up brake, around piston 
 
TRIPLE VALVE DEFECTS 125 
 
 rod or through the vent hole in top head. A leaky brake 
 pipe check valve 15 will let the air out of brake cylinder 
 into the brake pipe, but only when brake pipe pressure is 
 lower than cylinder pressure. This will be the case when 
 hose bursts or train breaks in two, or engineer reduces 
 the brake pipe pressure too much. In ordinary service 
 stops, leaks at this point do not affect the work of the 
 brake. 
 
 A test for leaky brake pipe check valve 15 in the quick- 
 action triples can be made at the brake valve. Reduce the 
 pressure 20 or 25 pounds from 70, and if the air comes 
 out full and strong and the equalizing piston seats its 
 valve promptly without a leak, make another reduction 
 of 15 or 20 pounds more. With this reduction the brake 
 cylinder will have about 50 pounds and brake, pipe 30. 
 If any brake pipe check valves leak, the 50 pounds will 
 try to equalize with the 30, and make it more than the 
 pressure above equalizing piston, which will raise and 
 let air blow out of exhaust as fast as it comes past the 
 check valve. 
 
 To locate a leaky rotary or any leak in brake valve 
 that lets off the brake, set the brake; close the cut-out 
 cock at once; brake will stay set and black hand will 
 raise or brake pipe exhaust open. Then open cut-out cock 
 and brake will release through exhaust port of triple. 
 
 To locate a leaky graduating valve, set the brake with 
 a light application; it will release through exhaust port of 
 triple about as quick as you can lap the brake valve. 
 Then, after recharging the auxiliary, set with a full 
 application and brake should stay set. 
 
 When a leaky graduating valve lets off the brake with 
 a light application, it is because the air from the auxiliary 
 leaks past the seat of valve 7 into the brake cylinder 
 until the auxiliary pressure is enough lower than brake 
 pipe pressure so triple piston will move slide valve up 
 into exhaust position, releasing air from brake cylinder 
 through the exhaust port. This it cannot do with a full 
 application, as in this case the air pressure has equalized 
 
126 BRAKE DEFECTS 
 
 between the auxiliary and cylinder, so a leaky valve cuts 
 no figure; air will not pass through after pressures are 
 equal. A leaky piston ring in the triple makes this matter 
 worse, as the brake pipe and cylinder pressures can 
 equalize and stick the brake. A leaky triple usually is in 
 bad order in other ways. 
 
 57. Q. If the brake is defective and leaks off through 
 piston packing, or any leaks in piping to brake cylinder, 
 is it any advantage to let all the air out of brake pipe in 
 such a case? 
 
 A. It seems to make a leaking brake hold a little 
 longer, but it is so short a time that it does not help very 
 much to stop the train. A gage put on this brake cylinder 
 will show that it only holds for a few seconds, and during 
 that time with a light pressure. The proper way is to stop 
 the leak. 
 
 58. Q. What makes the driver brake so slow to take 
 hold if coupled to a train when it works all right if engine 
 and tender are working without a train? 
 
 A. Generally it is because it leaks somewhere, so the 
 air leaks out without setting the brake when a light reduc- 
 tion is made for the train brake. See about the leaks the 
 first thing. The piston packing leather gets dry and hard 
 from being so close to the fire box and it needs soaking 
 up with oil frequently in the summer time. Tallow and 
 oil is good to put in driver brake cylinders, as it does 
 not evaporate so quickly as oil and keeps the packing 
 leather soft and pliable. To test for leaks, set the four- 
 way cock in plain triple for straight air (if possible) ; 
 or set the straight air; this will give you time to go 
 around and find the leaks. If the piston leather leaks, 
 the air will blow out of hole in the spring case or lower 
 head of push-down brake. Using the brake valve on 
 direct application position for service stops will sometimes 
 kick the driver brake off, after setting the train brake. 
 This is because when you use the direct application port 
 to set the brake you make a heavier reduction at head 
 end of the brake pipe than at rear end. The head end 
 
BRAKE DEFECTS 127 
 
 triples equalize for this reduction ; air from rear end 
 rushes up after you close the brake valve and releases 
 head triples. This is another reason why the direct 
 application should never be used unless you want the 
 emergency action of every brake. 
 
 59. Q. Why does the tender brake sometimes stick 
 and refuse to let off till auxiliary is bled a little, when 
 all the other brakes on the train release promptly? 
 
 A. Generally because not enough excess pressure is 
 carried. Always carry a sufficient excess if you want the 
 automatic brake to work properly. Overcharging the 
 head end of a long train will usually make the head brakes 
 apply and if the brake pipe pressure drops a little they 
 will stick till kicked off by going to full release for a 
 few seconds. Some old tenders have 12 x 33-inch aux- 
 iliary reservoirs for an 8-inch brake cylinder; if, in this 
 case, the piston travel is short, the brake piston pressure 
 is six or seven pounds higher than other brakes equalize 
 at and brake pipe pressure must be raised correspond- 
 ingly higher to release tender brake. Then the tender 
 triple gets more sand and dirt in it than any other triple, 
 which causes it to wear and get defective. A leaky triple 
 piston packing ring will allow any brake to stick unless 
 very high excess is used, as it will let air equalize past 
 the triple piston into auxiliary without moving piston up 
 to exhaust position. 
 
 60. Q. If the brake pipe is charged up with a high 
 pressure from main reservoir when brake is released for 
 a second application stop, will the brake set again at once 
 with a small reduction of brake pipe pressure? 
 
 A. It will not set again until the brake pipe pressure 
 is reduced below the auxiliary pressure. For example : 
 If the brake has been set tight, the auxiliary pressure 
 will be about 50 pounds for the first application; if you 
 turn 90 pounds into brake pipe you must let 40 pounds 
 out again, to draw brake pipe pressure below 50, before 
 the triple piston will move; all this time your train is 
 getting nearer the stopping point. This is one of the 
 
128 STICKING BRAKES 
 
 reasons why you run by when trying to make a stop this 
 way; it takes so long to draw your brake pipe pressure 
 down where it was before. In case you expect to apply 
 the brake at once after releasing it wholly or partly, put 
 the brake valve on full release for an instant, just long 
 enough to charge up the brake pipe its whole length, and 
 then put it on lap. This movement will release triples 
 and hold your brake pipe pressure so near the auxiliary 
 pressure that the triple is ready to act instantly with light 
 service application. This is the proper method of making 
 partial release if you are going to stop too soon or expect 
 that slippery track will skid the wheels just as the final 
 stop is made. 
 
 61. Q. Why are some of the train brakes more likely 
 to stick on a long train after a light application than after 
 a heavier one? 
 
 A. Because after a light application the pressure has 
 been reduced so little in the auxiliaries that the main 
 reservoir does not have enough more pressure to move all 
 the triples. A light reduction on a long train does not 
 always move all the triple pistons and their feed ports 
 remain open ready to take brake pipe air, which holds the 
 brake pipe pressure down. With a heavy reduction the 
 triples all operate, no feed ports will be open till triples 
 release and the brake pipe pressure will raise higher at the 
 moment of releasing brakes. This is a trouble peculiar 
 to long trains only; small main reservoirs and sticky 
 triples with leaky packing rings make it worse. 
 
 62. Q. Is it possible to let off part of the brakes and 
 leave part of them set? 
 
 A. Yes. After a full application this can be done, 
 especially if brake pipe pressure has been reduced much 
 more than 20 pounds. When you go to full release, if 
 the brake pipe is not at once charged up above the highest 
 auxiliary pressures by the main reservoir air, as soon as 
 the brake pipe pressure is a little higher than the lowest 
 pressure in any auxiliary, its triple will move up into 
 exhaust position, releasing that brake. Then this auxiliary 
 
BRAKES CREEPING ON 129 
 
 will begin to recharge through feed port and help hold 
 brake pipe pressure down till that auxiliary and the brake 
 pipe are charged up high enough, when another brake 
 will let off; and so on until all are let off. The brake 
 with longest piston travel usually lets off first, because it 
 has the lowest auxiliary pressure ; this operation takes 
 place after a full application when piston travels are 
 unequal. When pumping off the stuck brakes you have 
 to raise the pressure in all the auxiliaries of the released 
 brakes as well as in the brake pipe. When you think the 
 brakes are releasing in this manner, lap the brake valve 
 and pump up the excess ; when this is turned back into 
 the brake pipe they will usually all let go. Do not attempt 
 to work steam, you will risk a break-in-two. 
 
 63. Q. Why do some of the brakes creep on when 
 the train is running? 
 
 A. Because there is a leak that takes air out of the 
 brake pipe; this leak may be in the brake pipe, triple valve 
 or auxiliary reservoirs. It can also be on account of the 
 auxiliaries not having all equalized after releasing the 
 brake. The auxiliaries at the head end of train will charge 
 to a higher pressure on full release than the rear ones; 
 when the brake valve is moved to running position the 
 higher auxiliary pressure will cause the head triples to 
 move to service position. If air is fed into the brake pipe 
 faster than it leaks out, the brakes will not creep on. If 
 air sanders use so much air that the pump can not supply 
 air to hold up main reservoir and brake pipe pressures 
 the brake will set; this is a main reservoir leak taking 
 air out of brake pipe. 
 
 64. Q. How can these brakes be released the quickest 
 and surest way? 
 
 A. If a main reservoir leak reduces brake pipe press- 
 ure, shut off the escape of air if possible and run the 
 pump faster till brake pipe pressure is raised so brakes 
 will release. If a leak from brake pipe sets the brake, see 
 that you have excess pressure first, then turn it back into 
 brake pipe by moving the brake valve handle from run- 
 
130 STICKING BRAKES 
 
 ning position to full release just long enough so the rush 
 of air from main reservoir will charge up the brake pipe, 
 and putting it back to running position before any of the 
 auxiliaries are charged any higher. This forces the triple 
 valves of the sticking brakes up into release position, so 
 air from brake cylinder exhausts and does not give time 
 to raise the pressure in any reservoir. Sometimes this 
 must be done a second and third time to release all of 
 them. If brake valve is held on full release long enough 
 to charge a reservoir higher than the standard brake pipe 
 pressure, that brake will be sure to set as soon as brake 
 valve is returned to running position. This is the case 
 when the feed ports are too large in proportion to the 
 auxiliaries that they supply. 
 
 65. Q. If governor is set at 70 pounds with D-8 
 valve or any brake valve of that type, and brake pipe is 
 charged from main reservoir higher than that pressure, 
 is the brake apt to creep on? 
 
 A. Yes; the pump is stopped and will not start again 
 till brake pipe pressure is lowered to 70 pounds. The 
 excess valve will remain shut so no air can pass into the 
 brake pipe, and if there are any leaks the train pipe press- 
 ure will drop. During this time brake is pretty sure to 
 go on. 
 
 66. Q. How can this be avoided? 
 
 A. By not allowing main reservoir to charge brake 
 pipe and auxiliaries at over 70 pounds. When standing 
 at a water tank, or any stop, with brakes set, the main 
 reservoir pressure is apt to run very high. If all of this 
 is turned into brake pipe and allowed to equalize at over 
 70 pounds, with brake valve carried in full release reg- 
 ularly, there is no way to prevent the brake setting if 
 brake pipe leaks. In this case, set it a little and at once 
 release it; this will reduce the brake pipe and auxiliaries 
 below 70 pounds, so pump will go to work and you can 
 hold brake off. 
 
 67. Q. In making a stop how should you release the 
 brakes on a freight train? On a passenger train? 
 
RELEASING BRAKES 131 
 
 A. On a freight train, not till it has entirely stopped, 
 or you run the risk of train breaking in two. The brake 
 pipe pressure on a long train is increased next the engine 
 first; hence brakes let go there first; even if it is only a 
 few seconds sooner. Part of the shock is from unequal 
 piston travel, which gives unequal piston pressure ; brakes 
 with long piston travel let go first after a full application. 
 With a "part air" train the slack of entire train runs up 
 against the head cars ; releasing brake while train is 
 moving slowly, is liable to part the train; working steam 
 before slack is all evened up in train is sure to break it in 
 two. The ET brake and K triples will hold the slack 
 against the engine. Using pressure retainers on the head 
 end of such a train or the Straight Air brake on engine 
 will hold the slack all bunched till all triples have released 
 when retainer handle can be turned down or engine brake 
 released. 
 
 With a passenger train, release should be made just a 
 few feet before the train stops, so there will be just 
 enough power to stop the train and avoid tilting the 
 coach truck forward at the instant the train stops. If 
 the brake beams are hung from the body of the car the 
 truck will not tilt forward, but there will be a shock at 
 stopping if the brake power is severe. 
 
 68. Q. Why should a brake on a short passenger train 
 be let off just before coming to a full stop? 
 
 A. Because, as most all coaches have outside hung 
 brakes, the brake shoes pull down on the forward end of 
 the truck and push up on the back part of the truck and 
 thus tilt the truck; if brake is not let off until after the 
 train stops, when the truck rights itself it rolls the wheels 
 back a little and throws the body of the coach back, 
 annoying the passengers, even if it is not severe enough 
 to throw them against the seats. This trouble is not felt 
 so plainly by the engineer when he has a good driver and 
 tender brake, as the brake on the coach is what jerks the 
 coach. Then less power is required to stop a train going 
 very slow, as at the instant of stopping, than when run- 
 
132 TWO-APPLICATION STOP 
 
 ning at full speed; if power enough- is left on to hold a 
 train at full speed, it must stop very forcibly at slow 
 speed. The brakes should begin to release about half a 
 rail length from where the train finally stops ; a little 
 farther if going very fast, a little less if a very slow 
 stop is being made. Practice will teach you the distance. 
 There is an exception to this rule in the case of a very 
 long passenger train, say over twelve coaches, especially 
 if it is not vestibuled and the buffer spring slack all taken 
 up solid .between the cars. Experience will teach you that 
 in stopping a train of this length less shock will be given 
 the front end of train if brake is held on moderately tight 
 just at the instant of stopping till train stops; i. e., handle 
 a very long passenger train about the same as a freight 
 train of the same length. 
 
 69. Q. How should a "two application stop" with a 
 passenger train be made? 
 
 A. Make a full application when running at a high 
 speed so as to have a high brake power at high speed. 
 When the speed is reduced to 15 or 18 miles an hour, and 
 you are stopping short of the desired point, go to full re- 
 lease for an instant, just long enough to start all triples 
 to exhaust, with the ET brake, stop on running position 
 for an instant to partially release the engine brake, then 
 begin the second application at once by a moderate reduc- 
 tion which should set all brakes at a moderate power. 
 You can increase the brake power with another reduction 
 so as to stop at the exact point, and, if necessary, leave 
 the brake set without having power enough to tilt the 
 trucks and shock the passengers. This method reduces 
 the risk of sliding wheels, as brake is set tight at high 
 speed when wheels do not slide, then let off and set with 
 less power at slow speed. With the L type triples the 
 brake can be released a little at a time just before the 
 stop. 
 
 70. Q. Describe the position of the handles to all 
 valves and cocks in the air brake and signal equipment, 
 whether open or shut. 
 
THE BRAKE PIPE 133 
 
 A. All the handles, except to angle cocks, stand at 
 right angles or crosswise of the pipes when they are 
 open; parallel to pipe when cut out, plain triples and 
 pressure retainers follow the same rule, their handles are 
 horizontal or crosswise when cut in. The crooked handle 
 of angle cock is parallel with pipe when cut in. This is 
 so the hose will protect handle from being struck by any- 
 thing flying under the car and getting shut off, as the 
 old style straight handled cock is liable to. A small 
 groove square across the end of plug shows whether cock 
 is open or shut, as the groove runs same way with hole 
 in plug. 
 
 71. Q. Do you understand that all air cars in a train 
 should be connected and brake pipes charged with air, 
 whether brakes are cut in or not? Why? 
 
 A. Yes. All brake pipes should be coupled up and 
 air working through them, so that if the train breaks in 
 two anywhere in the line, all brakes will be set that are 
 working. Interstate Commerce Commission rules say so. 
 
 72. Q. What should be done with a car on which the 
 brake pipe is broken? 
 
 A. If it cannot be plugged at leak and allow air to 
 pass freely to cars behind it, it must be switched behind 
 all other air cars; have air in hose that is coupled to next 
 car in front; brakeman should look after that car and all 
 behind it. If you have two J^-inch air brake hose, the 
 signal hose can be taken off signal line, brake hose put on, 
 and signal line used for brake line through that car 
 to get air back to other cars. 
 
 73. Q. If the pipe at one end of the car should come 
 loose, would you consider it dangerous? Why? 
 
 A. Yes. If the pipe at end of car gets loose so cock 
 will bounce up and down and strike the handle end of 
 plug against the dead wood or any part of car, it is liable 
 to work shut gradually. This is caused by the spring 
 which holds the plug in its seat, turning the plug a little 
 each time it strikes. If the spring is wound one way, it 
 works open; if the other way, it works shut. The later 
 
134 INSPECTING BRAKES 
 
 style of angle cock handle prevents the plug turning 
 around. 
 
 74. Q. 1. After coupling to train why should you 
 not immediately try to apply the brakes for inspection? 
 2. How long should you wait? 
 
 A. Because you must wait till a full pressure of 70 
 pounds is stored in auxiliaries so a full application of 
 brakes can be obtained to get the piston travel. The time 
 you should wait depends on the pressure maintained in 
 the brake pipe from the moment of coupling on; if 70 
 pounds is held steadily, two and one-half minutes is the 
 shortest time for some of the older makes of triples. The 
 triple valves of late design charge to 70 pounds in about 
 seventy seconds. The pressures must be equaF in all 
 the auxiliaries, even if it takes longer before testing. 
 When the governor stops the pump with the standard 
 pressures shown on both hands of the gage it is usually 
 long enough. 
 
 75. Q. Should the train brakes be inspected? How? 
 When? Why? 
 
 A. Yes, by applying them with full service application 
 in the same manner as for a station stop with a moving 
 train; then examine each car to see that the piston travel 
 is the proper length and that there are no leaks that will 
 let brakes off; then release them and examine each car to 
 see that all release and that there are no leaks through 
 exhaust port. They should be inspected at all terminals 
 and tested whenever train breaks in two, or cars are taken 
 on or set off, as the wrong angle cocks may be closed or 
 left closed at such points. This is necessary because it is 
 not safe to depend on a brake till it is shown that it will 
 set and release properly. Hand brake should always be 
 let off before testing. If pressure retaining valves are 
 tested they should be turned up after the first test is com- 
 pleted, a reduction of ten pounds made in brake pipe, and 
 the brake pipe recharged to release the triples. The re- 
 tainers should then be examined to see that they are all 
 quiet; handles should then be turned down. If they are 
 
INSPECTING BRAKES 135 
 
 in good order the air held in brake cylinder will come out 
 as soon as handle is turned down. If no air blows out the 
 retainer is useless, look for leaks at pipe joints and brake 
 cylinder packing. 
 
 76. Q. Would you consider a train safe to leave with 
 if the brakes had been tested by opening angle cock at 
 rear of train? How would this affect your main reservoir 
 pressure? 
 
 A. No, sir! not unless some other test has been made. 
 This would not set all the brakes unless the brake valve 
 was on lap. It would draw down main reservoir pressure 
 and waste air without doing any good. This test is only 
 good to show that air hose are coupled, angle cocks open 
 and brake pipe charged from engine to last car. 
 
 77. Q. If with 70 pounds brake pipe and auxiliary 
 pressure you release the brake and apply it again imme- 
 diately, would you expect to obtain the same power you 
 had before? How long would it take to regain the 
 original pressure? 
 
 A. No, sir! never. About forty seconds, if main 
 reservoir had 35 or 40 pounds excess over auxiliaries, 
 sometimes less time. The feed ports in triple valves 
 which regulate the time of charging are not always the 
 proper size for the reservoirs they supply. A short train 
 and light application would reduce this time to twenty 
 or twenty-five seconds. Generally it takes longer than 
 the tests show it with everything in good working order, 
 for the feed ports are not always clean and strainers free. 
 The pressure at which auxiliary equalized after first ap- 
 plication is what you begin with on second application 
 after first release, generally it is fifty after first full 
 application ; with full release of brake and immediate 
 application you get thirty-five and a little more on second 
 full application ; the third time you will have less than 
 30 pounds piston pressure. 
 
 With the High Speed brake pressure of 110 pounds 
 you can make two successive applications with 20 pound 
 reductions and a release between before you get down 
 
136 SIZE OF FEED PORT 
 
 to 70 pounds with the type L triple, the supplementary 
 reservoir recharges the service auxiliary almost instantly. 
 
 78. Q. Can an auxiliary reservoir be recharged with- 
 out releasing the brake? 
 
 A. No, not if the triple valve is in good order. The 
 ports are so located in the triple valve that the feed port 
 through which auxiliary is charged does not open till after 
 exhaust port is open, which releases the brake first, 
 recharge the auxiliary afterward. By the use of a press- 
 ure retaining valve, which holds some of the air in the 
 brake cylinder, the auxiliary can be recharged without 
 releasing the brake entirely. If an auxiliary is recharged 
 before the triple is moved to exhaust position, brake pipe 
 pressure will not be able to move the triple, and the 
 brake must be bled off. 
 
 79. Q. Why does it take so long to regain the original 
 pressure in the auxiliaries after releasing brakes? 
 
 A because the feed port in the triple through which 
 the air passes from brake pipe to auxiliary is small. This 
 feed port is shown at m in the plain triple, and at i in 
 the quick-action triple. It is necessary to have this port 
 small for two reasons ; first — when setting the brake, the 
 feed port must be small or when brake pipe pressure is 
 reduced at brake valve for a light service application, the 
 auxiliary air could flow around the triple piston through 
 the feed port i as fast as it is taken out of brake pipe; 
 so triple piston would not move. If the feed ports .were 
 larger, when brakes are to be released, it would be im- 
 possible to charge up a long brake pipe from the engine 
 and hold the pressure up quick enough to release all the 
 brakes at as nearly the same instant as possible, as the 
 first few ports to open would take some of the brake pipe 
 air and hold the pressure down ; if they were large 
 enough a few of them would do this. The quick-service 
 triples and L triples are now arranged to help this matter 
 out. See questions 46 and 55. These feed ports must 
 be the proper size for the auxiliaries they supply, so 
 different sized auxiliaries will charge to the same pressure 
 
LEAKAGE GROOVE 137 
 
 in the same time from the same brake pipe. The auxiliary 
 reservoir for a 10-inch coach brake holds about 3,100 
 cubic inches, that for an 8-inch freight brake holds about 
 1,620 inches ; therefore a feed port for a 10-inch brake 
 reservoir must be the right size to pass nearly twice as 
 much air through in the same given time as for an 8-inch 
 brake. This is the reason for using only the proper triple 
 for each reservoir. Then the reservoirs are a certain size 
 for the brake cylinders they supply, so an auxiliary press- 
 ure of 70 pounds will equalize with brake cylinder of 8 
 inches piston travel at 50 pounds. This in turn gives a 
 standard piston pressure for which to arrange the brake 
 leverage on each car or engine, so as to get the full 
 effective braking power. The older style of plain triples, 
 F-24, used with 8-inch engine brakes, have feed ports 
 the proper size for 12 x 33 auxiliaries. This gives a 
 quicker recharging and a prompter application with these 
 brakes in switching service. If engine brake creeps on 
 from this cause when coupled to a train they are easily 
 released from the brake valve as they are close to the 
 brake valve and main reservoir. The present style of 
 plain triples, G-24, have the proper sized feed ports for 
 the 8-inch brake. 
 
 80. Q. Where are leakage grooves located? What 
 are they for? Is it necessary to allow for them when 
 applying the brake? How do you do this? 
 
 A. Leakage grooves are small grooves cut in the 
 inside of brake cylinders at the top or side. The later 
 freight brake cylinders have them at the side.. When the 
 brake piston is in release position this groove is uncovered 
 so that a small amount of air passing into the brake 
 cylinder from a very light application, or when the brakes 
 are creeping on, will escape through the groove without 
 moving the piston. When the triple valve is in relea.-e 
 position any air that gets into the cylinder from leaks can 
 pass out through the exhaust. They also prevent the 
 brake holding when the piston travel is taken up too 
 short. In old equipment they are long enough so that a 
 
138 PISTON TRAVEL 
 
 piston movement of three inches is necessary to cover the 
 groove, in later equipment they are much shorter. It is 
 necessary to allow for them at the first reduction by mak- 
 ing it strong enough so that the brake piston will go far 
 enough at the first movement to cover the groove. Five 
 to seven pounds reduction should do this ; a short train 
 does not take as heavy a reduction as a long one. The 
 leakage groove must be covered at the first reduction or 
 the air passing into the cylinder will be wasted, a number 
 of small reductions will waste all the air so train cannot 
 be stopped. This is a common fault in operating the 
 brake. If the hand brake is set on a coach or the piston 
 travel shortened so the leakage groove is not covered, 
 that brake will not hold. 
 
 81. Q. Does the difference in travel of pistons in 
 brake cylinders increase or decrease your braking power? 
 Why? 
 
 A. Long piston travel decreases the braking power 
 because it gives less air pressure on piston, short piston 
 travel gives higher piston pressure. With light applica- 
 tions this difference is more marked than with a full 
 application. A 10 pound reduction will apply a 4-inch 
 travel brake solid, while it will not give any braking 
 power with an 11-inch travel. With 8-inch piston travel, 
 70 pounds auxiliary pressure gives 50 pounds on piston 
 per square inch. An inch difference in the travel make 
 close to two pounds in pressure, thus 7 inches would give 
 nearly 52 pounds, 9 inches a little over 48 pounds. The 
 piston travel can be correct with a heavy car and high 
 leverage, and the shoes will not clear the wheel much 
 when released. If levers and brake beams spring much 
 with 8-inch travel, the shoes will not have much slack 
 when let off. Brake levers may catch on something so 
 piston travel is correct and shoes not touch the wheels. 
 With the straight air brake or the distributing valve the 
 piston travel does not affect the pressure on the brake 
 piston, as these valves do not take air from an auxiliary 
 as the triple valve does. 
 
CUTTING OUT BRAKES 130 
 
 82. Q. How do you cut out the brake on engine and 
 tender without interfering with the train brake? 
 
 A. By turning the four-way cock in top of old style 
 plain triple so the handle is at an angle of forty-five 
 degrees ; this will lap all ports and allow no air to pass 
 from brake pipe or auxiliary to brake cylinder ; see that 
 brake is entirely released first, and open bleeder in aux- 
 iliary. With the later type of engine triple the cut-out 
 cock is in the cross-over pipe, so closing the cock cuts 
 out the triple. Open bleeder in auxiliary so the brake 
 cannot creep on from a leak in the triple. To cut out the 
 locomotive brake from the distributing valve, shut the 
 cock in the pipe leading to the cylinders. To cut out 
 the automatic action of the distributing valve close the 
 cock in the brake pipe connection. 
 
 83. Q. What is the difference between cutting the air 
 out from a car and cutting it out from a brake? 
 
 A. Shutting the angle cock at the end next engine 
 cuts out that car and all behind it; shutting the cross- 
 over cock between brake pipe and triple cuts out that 
 brake only and allows all the rest to operate. 
 
 84. Q. If one brake beam under a car was broken 
 "how would it affect that brake? How would you cut out 
 the brake on that car and allow air to pass to other cars? 
 
 A. If one brake beam or rod is broken, the brake on 
 that car is useless and it must be cut out by shutting the 
 cock in the cross-over from brake pipe to triple, or by 
 turning the four-way cock in plain triple. This will allow 
 air to pass through brake pipe to other cars without 
 operating disabled brake. Be sure the brake with plain 
 triple on either engine, tender or coach is released before 
 four-way cock is turned, as no air can get out of brake 
 cylinder after cock is turned. All quick-action brakes can 
 be bled by opening the bleeder in auxiliary reservoir and 
 allowing all air to escape, as the cut-out cock does not 
 close the communication between brake cylinder and the 
 bleed cock in auxiliary. 
 
 85. Q. In going down a long, steep grade how would 
 
140 HANDLING TRAINS ON GRADES 
 
 you handle the brake to control the train? Why is it 
 necessary to recharge the auxiliaries on a hill? How is 
 this done? 
 
 A. Air braked trains on a long, steep grade must be 
 taken down at a moderate speed in order to control the 
 train; much less brake power will hold it at a slow speed 
 than a fast one. If the train once gets the start of you it 
 may not be held at all. Run slow enough so you will not 
 need all the brake power to steady the train or you will 
 not be able to stop when necessary. When first passing 
 the top of a long, steep down grade, set the brake and 
 see if you can stop; if satisfied, release and go on, if not 
 satisfied the brakes will hold train, call for help and get 
 stopped. 
 
 Leaks in brake pipe, auxiliary, or brake cylinder press- 
 ures make it necessary to recharge; very few if any trains 
 are absolutely air tight. If brake pipe leaks, the brake 
 will set at full power, which should stop the train; this 
 will call for a release and recharging to standard pressure. 
 Auxiliary or brake cylinder leaks will reduce the braking 
 power so train will run away; to avoid this disaster it is 
 necessary to recharge the auxiliaries frequently; you can 
 then hold the auxiliary pressure up close to the standard 
 amount all the way down the hill and have plenty of 
 brake power. As triple valves release a brake and re- 
 charge the auxiliary afterward, to hold the brake set while 
 auxiliaries are recharging, pressure retaining valves are 
 used, which hold some of the air in the cylinder after 
 triple has gone to release position. Before starting down 
 the grade turn up the handles or retainers, use as many 
 as possible and not have them stop the train at any of the 
 let-ups in the grade. The more retainers used the less 
 hot wheels, as the holding power is on a greater number 
 of cars ; if the full brake power is used on any cars all the 
 way down a long hill the wheels are liable to get so hot 
 as to damage them. Make a moderate application at first; 
 when the train slows down, release and leave brake valve 
 in full release position to recharge as quickly as possible, 
 
HANDLING A TRAIN 141 
 
 which should not take over forty-five seconds. On the 
 next application, a light reduction will usually steady the 
 train, as with retainers used the pistons are over the 
 leakage grooves and considerable pressure held in the 
 cylinders. Light reductions give more power to brakes 
 with retainers working than heavy reductions without 
 the retainers ; this saves both brake pipe and auxiliary 
 air. Pick out places where sharp curves or let-ups in 
 the grade slow up the train to recharge auxiliaries. Air 
 braking on a long hill should be learned on that particular 
 hill — no exact rule can be set down; the instructions here 
 given are general. To test the brake power developed on 
 various cars, feel of the wheels at the bottom of the hill 
 when possible; cold wheels on some cars and hot wheels 
 on others show unequal braking power. Use the in- 
 dependent engine brake while recharging, this will help 
 hold the train. 
 
 86. Q. What is the difference between handling a long 
 train having part air in front and one entirely of air? 
 
 A. A great difference. It requires more skill and 
 practice to make a good stop with a part air train than 
 with a full air train. With part air you must be careful to 
 bunch the train so slack will run up easily against the 
 air brake cars before setting the brake very tight ; this 
 takes some seconds. If you make a second reduction 
 before the rear end feels the effects of the first one, the 
 two light applications make one heavy one, as far as the 
 shock to the rear cars is concerned. When backing up, 
 extra care must be taken, or train will break in two and 
 merchandise be damaged in cars. With a full air train 
 the first reduction of brake pipe pressure takes so much 
 longer to start all the triples to work that you must wail 
 about as much longer after the brake pipe exhaust stops 
 flowing before making a second reduction. With a long 
 all air train and new empty cars with short piston travel, 
 or coaches on the rear end, it is a good rule to apply the 
 brakes before shutting off steam, while the train is 
 stretched, this prevents the higher power brakes at the 
 
142 DOUBLE HEADING 
 
 rear pulling the train in two. The brakes are longer in 
 releasing, and this requires more time after releasing 
 before the train runs free. 
 
 87. Q. If you had a freight train with "part air" cars 
 in operation and you used the emergency application, 
 would it make any difference whether the slack was out 
 or not? In case there was a shock, on what part of the 
 train would it fall? 
 
 A. Using the emergency brake with part air train 
 always sets the head end hard and solid; if slack is all 
 run up against the engine the shock is not as great. In 
 any case the rear end gets all the damage ; the weakest 
 cars and draft gear behind air cars suffer. Empty flat 
 cars next the air are likely to be wrecked. 
 
 88. Q. Which engineer should handle the brakes in 
 double-heading, and what should the other engineer do? 
 
 A. The leading engineer should handle all the brakes 
 when double-heading, as he is the only man who can see 
 clearly all the signals and the condition of the track ahead, 
 so as to act promptly to stop the train when necessary. 
 The following engineer should shut the cut-out cock 
 under his brake valve, which should be in running posi- 
 tion with the 1892 valve, on lap with the H-5 valve, on 
 running with H-6, keep the pump running and a full 
 supply of air. If there is no cut-out cock, place brake 
 valve on lap so no air can get into the brake pipe from 
 his main reservoir and plug up train pipe exhaust elbow, 
 so that when head engineer releases brakes the brake 
 pipe air will not escape through second brake valve. If 
 cut-out cock works open or is left open so main reservoir 
 air feeds into brake pipe; when the leading engineer 
 makes a service reduction the air from the following 
 engine will hold the equalizing piston of head engine up 
 so that brake pipe exhaust will blow strong and con- 
 tinuously. If head man is sure that second engine is 
 feeding into the brake pipe when brakes are to be set, 
 he should go to emergency at once, whistle for brakes, 
 get stopped or have second cut-out cock closed. The 
 
BURSTED AIR HOSE 143 
 
 emergency port of first brake valve will take air out of 
 brake pipe faster than the second pump and reservoir can 
 supply it, especially if second valve is on running position. 
 
 When testing the train brakes from a double-header, 
 be sure that main reservoir air of following engines is 
 cut out from brake pipe and that the test is properly made 
 from leading engine. 
 
 If the rules allow it and a definite arrangement is made 
 between the engineers, the second man can assist in releas- 
 ing stuck brakes or in charging auxiliaries by opening his 
 cut-out cock when signaled to do so with brake valve in 
 full release. As soon as train is moving cut-out cock 
 should be shut so the leading engineer can stop the train 
 at once if necessary. 
 
 The rule to carry brake valve on running position with 
 cut-out cock shut varies on different railroads. One 
 prominent system requires that the brake valve be carried 
 on emergency position so that in case of necessity brake 
 will go on at once if cut-out cock is opened. Rules of 
 your own road apply in this case to position of valve. 
 
 89. Q. What would you do if an air hose burst? 
 How would you know it? Should you have extra hose? 
 Of what kinds? 
 
 A. Put brake valve on lap; whistle out a flag. If in 
 a dangerous place to wait, or when a train is close behind, 
 shut the first cock ahead of bursted hose ; let off brake 
 on head end from engine; bleed the cars behind bursted 
 hose; get to a safe place and replace the bursted hose 
 with a new one. If with bad grades or all air train, put 
 in a new hose anyway, if possible. It would be known 
 at once, because brake would set; black hand would 
 drop way down ; main reservoir pressure would also run 
 down quickly. Put brake valve on lap to save your main 
 reservoir air. To locate the bursted hose put brake valve 
 on running position just so you will keep a little pressure 
 in the hose and trainmen can hear the air blowing out of 
 bursted hose and find it. 
 
 Extra hose chould be carried on engine, one of each 
 
144 BREAK-IN-TWO 
 
 kind used. Trainmen should have a standard brake hose, 
 a signal hose and one double-end or splice coupling to use 
 in case drawheads or coupling of cars are so long the 
 regular hose and couplings will not meet each other. 
 
 90 Q.. What course would you take should your train 
 break in two and set the brakes? 
 
 A. Put brake valve on lap, shut off steam, whistle out 
 a flag, shut the open angle cock on rear end of last car 
 connected to engine, let off brakes on head section from 
 the engine. When they are released and you get a signal 
 to do so, back up to rear section ; after coupling up to it, 
 if brakes cannot be let off from engine, bleed a few of the 
 sticking ones at back end of train until train can be 
 started. Be very careful to shut the bleeder as soon as 
 air begins to escape from triple exhaust port or you will 
 set some of the others, and that will hold the train longer 
 than necessary. All air bled out is wasted; it is done only 
 to save time, which is valuable in a case of breaking in 
 two. If you break in two or burst a hose on a bad grade, 
 shut both angle cocks next the opening in hose, this will 
 save any air that leaks past the triples into the brake 
 pipe and hold leaky brakes set till you are ready to release 
 them to move the train. 
 
 91. Q. Do you know what the pressure retaining 
 valve does? And how? If the pipe leading to this valve 
 should break off would you plug it? If you did, how 
 would it affect the brake? 
 
 A. The pressure retaining valve holds some of the 
 compressed air in the brake cylinder after the triple valve 
 has moved to exhaust position. It is attached to exhaust 
 port of triple valve by a piece of pipe and placed where it 
 can be conveniently reached when train is in motion. 
 When set to operate, its handle is turned up to a horizon- 
 tal position, which closes the direct opening, so the air 
 goes out slowly under a weighted valve ; and then passes 
 out of the case of valve through a small opening so air 
 escapes slowly. When pressure falls- to 15 pounds per 
 square inch in brake cylinder, this valve shuts off the 
 
PRESSURE RETAINER 145 
 
 escape altogether and holds the air in there, keeping the 
 brake set at 15 pounds ; this allows the auxiliary reservoir 
 to be recharged to full pressure again. It is used on long, 
 steep grades. If the pipe leading from the triple valve 
 exhaust to the retainer was broken off that retainer would 
 be useless. The pipe should never be plugged, as that 
 brake would not let off at all ; there would be no way for 
 the air to get out of the brake cylinder. 
 
 The old style t retainers held 15 pounds ; there are 
 other styles now made with heavier weights to hold 
 more. A later style has two weights, by placing the 
 handle in one position both weights come on the valve, 
 in another position only one weight bears on the valve, 
 this varies the pressure at the will of the trainman, who 
 turns up the handle with 50 pounds as the maximum. 
 
 92. Q. When air blows out steadily from the pressure 
 retaining valve, should it be closed or left open? 
 
 A. Left open by all means. The air that blows out 
 there comes from a leak in the triple valve ; shutting the 
 pressure retainer only stops air coming out there and 
 sets the brake, or if leak is a small one, makes it go out 
 through the leakage groove in the brake cylinder. If 
 pressure retainer is turned up, even if the brake does not 
 set right off, it will stay set when engineer sets it and 
 tries to let it off. Never turn up retainers unless you 
 want to hold the brake set the next time engineer releases 
 it. If the pressure retainer is broken off or the pipe lead- 
 ing to it from triple is broken or leaking badly, it does 
 not affect the operation of the brake in any way, except 
 that the retainer cannot be used on that car. If retainer 
 is broken off and pipe plugged the brake cannot be re- 
 leased at all from the engine, as there is no way for air 
 to escape from triple valve exhaust. If there is a leak 
 in pipe from triple valve to retainer, the retainer is of no 
 use, as air will escape from the pipe at leak when retainer 
 is set to work. Sometimes the pipe to pressure retainer 
 gets stopped up so air cannot get through it, in which 
 case the brake will set once and not release till bled off. 
 
146 AIR SIGNAL 
 
 It is not unusual to find nests of insects in the pipe right 
 at retainer. Pressure retainers are put on all freight 
 cars used in interchange service. Very few coaches have 
 them, only those running on mountain roads. Sleepers 
 and official cars usually have retainers. They are used 
 on level roads extensively to hold the slack bunched in a 
 long train; in this case they are usually applied to the 
 driver brake triple valve and located in the cab in easy 
 reach of the engineer, the straight air brake and ET 
 brake are much better. They are valuable aids in making 
 smooth stops with freight trains at water plugs. 
 
 93. Q. How does the air signal operate? If the air 
 signal on the engine whistled each time you released the 
 brakes, what would be the trouble? If the whistle blows 
 frequently when not in use, what is the matter? If it 
 blows one long blast? If the whistle is weak on engine 
 will it usually help it to blow out the signal hose on the 
 rear of tender? 
 
 A. The air signal valve on the engine is operated by 
 a reduction of pressure made in the signal line. This 
 signal line is supplied with air from the main reservoir 
 which passes through a reducing valve set at a much 
 lower pressure than the standard braking pressure, so the 
 operation of the brake will not interfere with the opera- 
 tion of the signal. The opening through the reducing 
 valve is choked down to restrict the flow of air into the 
 signal pipe and allow a reduction to be made in its 
 pressure. This reduction must be a sudden one, like an 
 emergency reduction for the triple valve, or the reducing 
 valve will feed air into the signal pipe as fast as it is 
 taken out at the car discharge valve. When the pressure 
 is reduced in the signal line at the car discharge valve 
 and this reduction extends to the signal valve, it affects 
 the pressure in chamber A above the diaphram 12 first, 
 so that the pressure in B under the diaphram lifts it up, 
 also raising the discharge valve 10 off the seat at 7, which 
 allows the air to pass to whistle. 
 
 If the diaphram gets bagged down, the pressure in B 
 
AIR SIGNAL DEFECTS 147 
 
 will raise the baggy part of the rubber and valve will not 
 raise off the seat. 
 
 The stem of valve 10 has the sides flattened, except 
 for a short distance at the top, where it enters bushing 9, 
 when this stem rises the flattened part comes above bush- 
 ing 9, and air from B also goes to the whistle, this 
 reduces the pressure in B. When the car discharge valve 
 is closed and the signal line pressure is increased by the 
 reducing valve, as the stem of 10 makes a moderately 
 close fit in the top of bushing 9, air passes into B slowly 
 while recharging. Chamber A is therefore charged up 
 first so diaphram is sure to set valve 10 promptly. 
 
 If the fit of the stem at the top of the bushing is too 
 loose the valve is liable to rise on its seat so the signal 
 will "repeat" and give more than one blast for each pull 
 of the car discharge valve. 
 
 This fit must be exact or the signal valve will not 
 always respond on both long and short trains to the 
 proper reductions. 
 
 If an air signal whistles each time brake is released 
 with standard braking pressure, it is a sign the reducing 
 valve is dirty and stuck open, so air goes back into main 
 reservoir from signal line each time main reservoir press- 
 ure is reduced in recharging train. In this case signal 
 line has main reservoir pressure. Clean the reducing 
 valve before the air signal hose bursts. The whistle will 
 give a shrill sound if pressure is too high. If the spring 
 in the old style reducing valve over diaphram is too stiff 
 it will do this. The improved reducing valve is regulated 
 for the proper pressure in the same manner as the feed 
 valve on F-6 brake valve. The reducing valves are set at 
 about forty-five now ; the old valves were set at twenty- 
 five pounds. This is so as to carry a lower pressure in 
 signal line than is used to operate the brake. To test 
 the pressure at which reducing valve operates, shut off 
 the pump, reduce the main reservoir about five pounds 
 at a time through brake valve till the signal whistle blows ; 
 this shows that the reducing valve is held open by the 
 
Signal Valve* 
 
 Pressure Reducing Valve* 
 
 Improved Reducing 
 Valve* 
 
AIR SIGNAL DEFECTS 149 
 
 spring so air can pass from signal pipe into main reser- 
 voir. If the signal whistle blows frequently when not in 
 use, there is a leak somewhere, which the jar of the 
 engine may open for an instant, or the reducing valve 
 may be out of order. If it sticks a little in its seat, as in 
 cold weather, a very small leak will cause the whistle to 
 give a strong blast — or a jar may unseat signal valve. 
 When it blows one long whistle some of the valves on 
 engine are stuck, or the car discharge valve is opened a 
 second and third time before the whistle stops blowing 
 the first blast; the pressure in signal line must equalize 
 each time between the blasts to make it work accurately. 
 If the stem 10 makes too close a fit in bushing 9 the 
 whistle will give only one blast for two or more reduc- 
 tions of signal line pressure, or a very small leak in the 
 signal line will cause signal valve to operate at intervals, 
 when a proper fit would allow it to work properly. If 
 the whistle bell works loose so it does not make a clear 
 sound, or is located near partly opened windows so a 
 strong draft of air blows across it, when train is run- 
 ning fast, the sound will be very weak. Blowing out 
 the signal hose at rear of tender gives all the valves a 
 chance to make a full opening and clean out the dirt. 
 To test the signal line for leaks, shut the cut-out cock at 
 the reducing valve; if the signal line leaks, the whistle 
 will blow as soon as the leak reduces the pressure. On a 
 double header both whistles should sound for the same 
 reduction of signal line pressure. If they do not, close 
 the cock in the reducing valve on the following engine 
 so only one reducing valve will be feeding into the train 
 signal line and thus allow the car discharge valve to do 
 its work properly. With both reducing valves cut in the 
 signal valve will not always operate on the leading 
 engine when the brake pipe reduction is made from the 
 rear cars of a long train. 
 
 With the ET locomotive brake, the same reducing 
 valve is used for the independent brake valve and the air 
 signal system. There is a non-return check valve in the 
 
150 trainmen's questions 
 
 signal pipe so the air can not get back from the signal pipe 
 when the independent valve takes air to apply the brake 
 as it would sound the whistle. This valve is shown at 
 question 37. 
 
 FOR TRAINMEN 
 
 94. Q. When coupling the engine to an air brake 
 train, equipped with quick-action triples and already 
 charged with air, which angle cock should be opened first ? 
 
 A. The one on engine always, so as to fill the hose 
 from engine. If cock on car is opened first, the train 
 brake is liable to set with emergency action. Get in the 
 habit of opening the cock on engine first, whether train is 
 charged or empty. 
 
 95. Q. When coupling an empty car to other cars 
 already charged and working, how should the angle cocks 
 be opened? 
 
 A. Open the one on empty car first, so the empty 
 brake pipe and empty hose will be connected. Then open 
 the angle cock on the charged car slowly so the pressure 
 in brake pipe will not be reduced any faster than the 
 engine, can supply it. This will prevent the brakes setting 
 on head end of train, which they will do with emergency 
 action if angle cock is opened suddenly. A little practice 
 will teach you the advantage of this. This applies to 
 coupling up the air on a train that has been separated to 
 open public crossings. When coupling to cars on a side 
 track that are going with your train, make the air brake 
 connections also, so the auxiliaries will be charging ready 
 for operating the brake while you are getting out on the 
 main track, this will save time in testing the brakes, as 
 they will be ready when train is all coupled up. When 
 air braked cars are to be set on a coming train, charge 
 these cars with air from the engine used to place them 
 on the train, it saves delay. 
 
 96. Q. If an angle cock at head end of train is only 
 
152 MAKING UP A TRAIN 
 
 partly opened or there is an obstruction in the brake pipe, 
 how will it affect the operation of the brake? 
 
 A. The brake can be set with service application, but 
 it releases very slowly as the air does not get back fast 
 enough to move all the triple valves to release promptly, 
 and any triples with defective packing rings back of the 
 obstruction will be sure to stick. With angle cock on 
 tender partly open, you cannot always get the emergency 
 action of the brake. When passing over the top of the 
 train, angle cocks can be inspected, as they are generally 
 far enough outside the end of car so the handles are 
 visible from top of car. When cocks are wide open the 
 handles are exactly over the hose. The old style plug 
 shut-off cocks come in the straight pipe just under the 
 end of car and cannot be seen when passing over the cars. 
 
 97. Q. Can an air brake train be made up so it will 
 be impossible to get the emergency action of the brake 
 from the engineer's brake valve? 
 
 A. If there are four cars with the brakes cut out at 
 cross-over near triples, or four cars with brake pipe only, 
 or with plain triples, next to the engine, the reduction of 
 air pressure in brake pipe will be so gradual on the fifth 
 car that you cannot get the emergency application of the 
 quick-action triples. It takes a sudden reduction at the 
 first quick-action triple to get the emergency. Switch the 
 plain triples among the quick-actions; you may need them 
 to make a sudden stop in an emergency. 
 
 981 Q. Why should train brakes be tested before 
 leaving a terminal or any point where the make-up of the 
 train has been changed? How should this test be made? 
 
 A. So you will know before starting out that the 
 brakes will work when necessary. After coupling the 
 engine on the train the pressure should be equalized in all 
 the auxiliaries, so all the brakes will set at the same 
 reduction of brake pipe pressure. The pressure should be 
 70 pounds in the auxiliaries in order to get a full applica- 
 tion of the brakes to test the piston travel. While the 
 engine is charging the train to standard pressure, which 
 
TESTING A TRAIN 153 
 
 will take some time on a long train, a careful inspection 
 should be made for leaks, and to see that all brake pipe 
 cocks, cross-over cocks and pressure retainer handles, are 
 in the proper position to operate all the brakes. When 
 standard pressure is reached the brakes should be applied 
 from the engine that is to handle them with a full service 
 application made in the same manner as when making a 
 station stop of the moving train. The trainmen or in- 
 spector will then examine each brake to see that it is set 
 with not less than five nor more than nine inches piston 
 travel. When all brakes are inspected, if they are set 
 properly, he will give a signal to the engineer to release 
 brakes and examine each brake to see that they have 
 released properly. If any brakes require adjustment of 
 piston travel it must then be done. Be sure to close the 
 cut-out cock in the cross-over while doing any work on 
 the levers or shoes, so the brake will not set and injure 
 the workman, opening it when adjustment is made. If 
 pressure retainers are to be used, they should be tested 
 after the piston travel is tested, by applying the brakes 
 with a 10 pound reduction, with retainer handles turned 
 up. As soon as the retainers are quiet, go along and turn 
 down the handles, the air should blow out from each of 
 them, which shows that they hold the pressure in cylinders. 
 Long freight trains can be tested by two inspectors, one 
 at each end working towards the middle of the train till 
 they meet. On passenger trains equipped with the air 
 signal, the signal for releasing after a test should be 
 given with the car discharge valve from the rear plat- 
 form of the last car. 
 
 99. Q. How can the piston travel on a freight car 
 be tested and then taken up the proper length when car 
 is not charged with air and brake operated? 
 
 A. See that the push rod going from piston to brake 
 cylinder lever is clear in against the bottom of piston 
 sleeve. Make a mark on the push rod even with the end 
 of the sleeve. Set the brake by hand as tight as possible, 
 with a club if necessary; the distance push rod is pulled 
 
154 DEFECTIVE BRAKE 
 
 out of the sleeve is the piston travel. There is generally 
 over an inch more piston travel when car is moving than 
 when standing; it is more with heavy braking power on 
 a car than with light. The piston travel on an empty 
 car may be very short, say four inches, and when loaded 
 the same car may have nine inches. When testing from 
 the engine, have the brakes set with full service applica- 
 tion, so you will get full piston travel. 
 
 100. Q. If the brake sets tight when you are charging 
 the auxiliary reservoir with air when first coupling the 
 hose to another car, should you cut out that brake? 
 
 A. If it is a quick-action triple it is a sign that air 
 leaks through some of the joints or valves in the triple 
 into the brake cylinder. Have the engineer set and release 
 the brake suddenly, once or twice; if there is dirt on the 
 rubber seat of the emergency valve which causes the 
 trouble, it will sometimes blow it off; if it does not make 
 the brake work all right, very likely some of the gaskets 
 are leaking badly; in such a case cut it out and bleed it. 
 With the freight brake there may be a leak in the pipe 
 from the triple valve to the brake cylinder which passes 
 through the auxiliary reservoir, nothing can be done on 
 the road for a leak of this kind but cut out the brake. 
 Most always in these cases the air blows out of exhaust 
 port or at the pressure retaining valve. With the plain 
 triple the plug cock in triple may be turned out for 
 "straight air." This will allow the air to go direct from 
 brake pipe to brake cylinder; none of it will come out of 
 exhaust port, as the triple is cut out from brake pipe and 
 cylinder. In this case cut it in for automatic. If the 
 handle is gone, or put on wrong, examine the marks on 
 the end of plug which show which way the' air openings 
 are and you will know which way to turn the plug. If 
 this plug cock leaks, the air can get past it from brake 
 pipe to brake cylinder. If brake will not work after one 
 or two applications, cut it out. With all plain triples the 
 brake should be released first, although the plain triple 
 used on freight equipment is built to bleed the brake 
 
PISTON TRAVEL 155 
 
 cylinder when brake is cut out. Sometimes this bleed 
 hole, which is in one side of plug cock in the plain freight 
 triple valve, gets stopped up, in which case it may be 
 necessary to let all the air out of the brake pipe — set 
 this triple for straight air which will bleed brake cylinder, 
 after which cock in triple can be placed in cut out 
 position. 
 
 101. Q. If the piston travel is too long or too short 
 what effect does it have on the brake as to its holding 
 power? 
 
 A. If it is too short it will not cover the leakage 
 groove, and air will leak out of cylinder; it must travel 
 three inches to cover this groove. If it is too long it will 
 strike the cylinder head, which will get the force instead 
 of the brake shoes ; it must travel twelve' inches to do this. 
 All brake pistons on coach, freight and tender equipment 
 of standard gage have 12-inch piston stroke, but should 
 not have over 8 or 9 inches piston travel. The piston 
 travel should be adjusted equally so the braking power 
 will be equal on all cars. Unequal piston travel gives 
 unequal braking power. This is the cause of many severe 
 shocks to long trains when first applying the brakes, an$ 
 still more severe shocks when releasing the brakes at a 
 slow speed. For instance, if some of the brakes have only 
 five inches piston travel, when the engineer makes the 
 first reduction of brake pipe pressure to apply the brakes, 
 those with short travel will set hard enough to take up the 
 slack of train quicker than the other brakes with long 
 piston travel. A first reduction in applying the brakes is 
 at least 7 pounds, less than this will not apply all the 
 brakes on a long train. This will give a pressure of 
 23 pounds on the piston with 5-inch travel, 8 pounds on 
 one with 9 inches travel, one with 10 inches travel will 
 not show any pressure at all, the shoes will just come 
 nicely up to the wheels. A few short travel brakes can 
 give serious shocks in a train that are plainly felt at the 
 rear end. 
 
156 LEAKY PACKING LEATHER 
 
 102. Q. If air blows past piston packing so freight 
 brake leaks off, can it be fixed on the road? 
 
 A. Sometimes this is from want of oil in the cylinder; 
 if the oiling plug near back cylinder head where it makes 
 a joint with cast iron auxiliary reservoir is taken out and 
 four or five tablespoonsful of black oil put in, it will soften 
 the packing so it will be tight. The piston sleeve should 
 then be turned around one-half turn to bring the softened 
 packing to the top of the cylinder. This should be 
 attended to by car inspectors, but is not always done. In 
 no case should oil or water be put in the hose and be 
 blown back into the triple with the air. It will carry the 
 dust and sand back in the pipe towards the triple; this 
 stops up the strainers, and if any gets by the strainers it 
 spoils the rubber seat of the emergency valve, and cuts 
 the triple to pieces very fast. Putting oil in the hose will 
 destroy the efficiency of the brake in very short time. 
 
 103. Q. How can the air signal whistle be operated 
 from the cars most successfully? 
 
 A. By allowing just enough air to escape at the car 
 discharge valve to reduce the air signal line pressure clear 
 to signal valve on engine, so that it will operate promptly, 
 then allowing car discharge valve to close and remain 
 closed till signal line is recharged to standard pressure; 
 this sometimes takes two seconds. A heavier reduction 
 with a longer interval between pulls is needed for a very 
 long train than a short one. The whistle will give only 
 one blast if the car discharge valve is opened a second 
 and third time before the whistle stops blowing the first 
 time. 
 
 If you make a second and third reduction before the 
 reducing valve on engine has had time to charge signal 
 line to standard pressure, the second and third blasts of 
 whistle will be very weak; in cold weather the reducing 
 valves do not always work perfectly. Sometimes when a 
 car discharge valve is opened, a sufficient amount of air 
 will seem to blow out there, but on account of an 
 obstruction near the brake pipe Tee under car it does not 
 
AIR SIGNAL 157 
 
 reduce the pressure enough at the engine to operate the 
 signal valve, and the whistle cannot be operated from that 
 car when it works from other cars. If the whistle blows 
 once when engine is coupled to train and cannot be 
 sounded afterward, look for a bad leak near rear end of 
 train. 
 
 If the whistle cannot be sounded from any cars back 
 of a certain car, the cock in back end of that car is shut, 
 or brake pipe is stopped up so you cannot make a sudden 
 enough reduction there to affect the signal valve on the 
 engine. If one blast of the whistle is used to start the 
 train without using any additional signal, remember that 
 one blast of the whistle can be given (without opening car 
 discharge valve) when you do not want the train started. 
 For instance, if the signal hose has been uncoupled (with- 
 out the knowledge of the engineer) for any purpose; when 
 the cock is opened enough air goes into empty hose to 
 sound the whistle, giving signal to start the train before 
 the man coupling hose can get out from between coach 
 platforms. Other causes may cause the whistle to give 
 one blast when not intended, therefore it is not always 
 safe to use one blast of the whistle when standing still, 
 to start the train. 
 
 104. Q. If hand brakes are used on part air train, on 
 which cars should they be used? 
 
 A. On the cars next behind the air braked cars so the 
 hand brakes will hold these cars and prevent slack run- 
 ning out of rear cars when air brakes are released. In 
 case of an emergency, all hand brakes should be set on 
 cars that do not have air brakes working. Care should 
 be taken that hand brakes are released on rear end of a 
 part air train first, air brakes last, when running forward 
 and in the reverse manner when backing a train. 
 
 105. Q. On an air braked passenger train in case the 
 engineer whistles for brakes what is the trainmen's duty? 
 
 A. Open tthe conductor's valve first. An angle cock 
 may be closed which prevents the engineer applying all 
 the brakes. If the air escapes freely and the brake goes 
 
158 LEAKING BRAKES 
 
 on, let hand brakes alone. If no air escapes from brake 
 pipe the brake may have already been set. Try the hand 
 brakes last, if the brake is set with air pressure you can 
 not move it by hand on any cars where the hand brake 
 sets opposite to the air brake. If it is not set with air 
 you can set it by hand, the' air may have leaked out of 
 cylinder. 
 
 106. Q. How do leaks affect the operation of the 
 brake on a car or coach? 
 
 A. If the brake pipe leaks the brake will continue to 
 set tighter after the first reduction till full set. Leaks at 
 the gaskets in the couplings can be stopped by putting 
 in new gaskets. Do not pound the guard arms of the 
 couplings as that will likely cause the hose to tear off 
 in a break-in-two. This leak affects a single car or a 
 short train more than a long train, as a short brake pipe 
 has less volume of air to leak out. 
 
 A leak from the brake pipe past the seat of the emer- 
 gency valve will allow the brake pipe air to equalize with 
 the brake cylinder when the brake is applied so the triple 
 slide valve has closed the exhaust port; this may stick 
 this brake especially if the triple piston packing ring also 
 leaks. 
 
 Any leak from the auxiliary which makes that press- 
 ure less than the brake pipe will move the triple to ex- 
 haust position; the air in cylinder will escape through 
 exhaust. With a leaky packing leather the air will blow 
 past it, coming out around the piston rod or sleeve; none 
 will come out of the exhaust. 
 
 107. Q. Where should you look for the trouble if the 
 brake applied properly, but would not release? 
 
 A. Very likely the pressure retaining valve was 
 closed; examine it first to be sure it is open. On some 
 sleepers and official cars both the triple valve and re- 
 tainer are concealed by the reservoirs and lockers, so it is 
 necessary to hunt them up beginning with the triple 
 exhaust, and if any pipe is attached following it up. If 
 the retainer pipe is stopped up or plugged no air can come 
 
STICKING BRAKES 159 
 
 out of triple exhaust. In cold weather the water from 
 drip valves of steam heated cars may splash over the 
 exhaust ports of triple valve and freeze on; this may 
 stop up the exhaust. 
 
 Levers or rods may catch on bolt heads or other pro- 
 jections under the car and hold the brake after the air 
 has exhausted from cylinder. If the release spring in 
 cylinder is broken the piston will not move back. Stopped 
 up strainers at the triple have been known to prevent 
 release of brake; air would pass out of valve, but could 
 not return quickly. 
 
 108. Q. In case a brake is noticed to be sticking 
 regularly, can you help it to release at the same time the 
 others do? 
 
 A. Short piston travel may cause this trouble. By 
 extending the piston travel it will lower the auxiliary 
 pressure on a full application so the triple is more likely 
 to move up promptly. As brakes are more apt to stick on 
 the rear of a long train than when next the engine, this 
 car can be set ahead if necessary to use its brake. 
 
 Leaky triple packing rings and choked strainers will 
 also cause this trouble. Better cut out the brake than 
 risk spoiling the wheels. Report this defect to the proper 
 party. 
 
 109. Q. How does the water raising system used on 
 Pullman cars operate? 
 
 A. This system has so many modifications and is so 
 complicated that a full description cannot be given here. 
 There is an air reservoir which is charged with the air up 
 to brake pipe pressure, sometimes directly from the brake 
 pipe; at other times from the brake auxiliary reservoir; 
 the latest method being to take air from the brake aux- 
 iliary. To regulate the flow of air into this air storage 
 reservoir there is a governor and non-return check valve; 
 the latest pattern of which is here shown. The governor 
 operates exactly like an air pump governor and should 
 be set at 60 pounds so it will not interfere with the air 
 brake pressure when that is below 60 pounds. In this 
 
160 
 
 WATER PRESSURE REGULATOR 
 
 same valve is a non-return check 38, to prevent air 
 coming back from the air storage reservoir, the stem of 
 which is made a neat fit at h so the air will feed past 
 it slowly and not take air too fast. Between the air 
 
 Water,Pressure Governor 
 Valve. 
 
 TO AIR STORAG-e 
 RESERVOIR 
 
 storage reservoir and the water reservoirs is a reducing 
 valve similar to the one used with the air signal, set at 
 20 pounds, which pressure is sufficient to give a good flow 
 
WATER RAISING SYSTEM 161 
 
 of water to the basins. If this reducing valve is set at 
 too high a pressure or gets dirty or stuck open so it does 
 not operate, the full pressure of the storage reservoir will 
 be in the water tanks, which not only uses too much air, 
 but is liable to splash the water all over the basins when 
 faucet is opened. The pressure in the water tanks oper- 
 ates this reducing valve. When the tanks are to be re- 
 filled the air supply is shut off, that in the tanks is 
 allowed to escape and water put in. When air comes out 
 into the basins with the water it is a good sign the water 
 is nearly gone. If no water or air comes out when you 
 are sure there is a proper air pressure, examine the 
 numerous cocks to see if any of them are closed. As 
 the cars are not all piped exactly alike it is usually neces- 
 sary to trace the pipes up and locate the stop cocks and 
 valves when making an inspection. There are also heat- 
 ing pipes connected with the devices of the water raising 
 system to prevent freezing up. Gages are usually located 
 up in the cars which show the air pressure in the storage 
 reservoir and water tanks, 70 in the former after charging 
 fully, and 20 in the water tanks. Suitable cocks under 
 control of the porters are provided to open or close the 
 passage of air from brake system to the water raising 
 system with a code of rules for operating these cocks. 
 
 110. Q. How does this water raising system affect the 
 operation of the brake? 
 
 A. When air is passing from brake pipe or auxiliary 
 to air storage reservoir it takes a little time to charge 
 the storage reservoir. If at that time brake is applied 
 as when making a terminal test of train brakes, air pass- 
 ing from the brake pipe will set the brakes tighter; if it 
 -goes from the brake auxiliary it will likely release that 
 brake, especially if set with a light application. If the 
 non-return check valve leaks back after air storage reser- 
 voir is fully charged, this air can flow in the brake pipe 
 if so connected and release all the train brakes. If the 
 connection is made to the brake auxiliary, a leaky check 
 valve will allow the volume of the storage reservoir to 
 
162 WATER RAISING SYSTEM 
 
 be added to that of the auxiliary and skid the wheels on 
 a full application. If all the stop cocks are not properly 
 operated and the valves in good order the work of the 
 brake may be interfered with, which shows that it is 
 absolutely necessary that they should be inspected at 
 regular intervals by competent men and be maintained in 
 proper order. If the governor which restricts the flow 
 of air from the brake system is in perfect order and set 
 at the proper pressure, unless a large amount of air is 
 used by the water system, the operation of the brake 
 will not be materially affected. If air is taken from the 
 brake system during the application of the brake it is 
 sure to affect the work of the triple valve, either to apply 
 the brake harder or release it. 
 
 The widespread use of this system requires that coach 
 inspectors inform themselves as to its construction and 
 operation, and that trainmen and porters comply strictly 
 with the rules for its operation. 
 
 111. Q. Can you get the emergency action of the 
 brake with the pressure retainer holding 15 pounds? 
 
 A. Yes; if the triple is in exhaust position, with brake 
 pipe and auxiliary equalized at 70 pounds, when a sudden 
 reduction of brake pipe pressure is made, it will move the 
 triple piston full stroke, opening the emergency port. 
 With air at 70 pounds pressure in auxiliary the emergency 
 piston, having only 15 pounds pressure under it, will be 
 forced down at once, the brake pipe air pressure will still 
 be so much above 15 pounds that brake pipe air will flash 
 into the brake cylinder, and this sudden reduction made 
 by the triple will affect the next triple so it will work 
 quick-action also. Question 50 explains why quick-action 
 can not be had after a moderate service application. The 
 use of retainers interferes so little with the quick-action 
 that the emergency action will jump over as many cars 
 with the brakes cut out at the cross-over cocks with all 
 retainers holding 15 pounds as when retainers are not 
 being used, provided the triple valve starts from exhaust 
 position and auxiliary recharged to 70 pounds. 
 
THE HIGH SPEED BRAKE 
 
 For ordinary speed, below thirty miles an hour, the 70 
 pound automatic brake is able to control the train in the 
 ordinary manner, but when the speed is much higher, 
 more power is required in proportion as the speed is 
 higher. It is the friction of the brake shoes on the wheels 
 that arrests tthe speed of the train and finally brings it 
 to a stop. In addition to arresting the momentum of the 
 train this friction must also arrest the rotary motion of 
 the wheels turning around at high speed; this takes con- 
 siderable brake power. There is a difference in the 
 amount of the friction of the same shoes and wheels at 
 different speeds, it being greater at a low speed than at a 
 high one. 
 
 What is called the co-efficient of friction, which is the 
 proportion between the brake power applied to the shoes 
 and their holding power, is about .074 at sixty miles an 
 hour, increasing to .241 as the speed is reduced to ten 
 miles an hour, to .273 at five miles an hour and just as the 
 final stop is made it is .330, so you see the brake shoes 
 really hold less at a high speed than at a low one, and 
 more brake power can be applied at the high speed than 
 could be safely used at a low one and make the holding 
 power about right for each speed. 
 
 Now it follows that if the full brake power was the 
 same for all speeds, if it was the proper power for a 
 moderate speed it would be much too low for a high 
 speed. If a high speed was the standard the full brake 
 power would be too high for the low speed, the wheels 
 would skid on the rail and a loss of about two-thirds of 
 the brake power would result. This would allow the 
 train to run considerable farther than if the wheels were 
 held back by the shoes just up to the sliding point — 
 without sliding. 
 
 Therefore, an attachment to the brake that would give 
 a very high brake power when first applied while running 
 at a very high speed and gradually reduce this brake 
 
164 THE HIGH SPEED BRAKE 
 
 power at about the same rate the speed was reduced, 
 would be proper for all speeds. 
 
 This brake power for moderate speeds has usually 
 been fixed at 90 per cent of the weight of the coach 
 when all the wheels have brake shoes applied to them, 
 and is about all that can be used without sliding the 
 wheels just as the final stop is made. 
 
 This reduction of 10 per cent from the total load on 
 the wheels with brake shoes applied is not exactly correct 
 for both light and heavy cars. If 10 per cent of the 
 weight of a car weighing 50,000 pounds is a proper 
 reduction to prevent wheel sliding, then the same number 
 of pounds reduction, i. e., 5,000 pounds should be enough 
 for a car weighing 100,000 pounds. The old 90 per cent 
 rule would give 10,000 pounds as the amount for this car, 
 or 5,000 pounds more than needed. Therefore, to get 
 the best service the same amount of reduction in pounds 
 should be made from all cars braked to the same per 
 cent. 
 
 For emergency, the high speed brake will apply the 
 brakes at first with a brake power of 125 per cent of the 
 weight of the coach and gradually reduce the cylinder 
 pressure as the speed is reduced, till it reaches the 
 standard of 60 pounds, which gives a 90 per cent brake 
 po.wer, at which point the reduction ceases, leaving the 
 cylinder pressure at the amount and the braking power 
 at the percentage at which the wheels will not slide when 
 the car is about to stop. 
 
 To get this increased brake power brake pipe and 
 auxiliary pressure is . increased to 110 pounds. With an 
 emergency application the pressure at first is about 85 
 pounds. The brake cylinder pressure is reduced by an 
 automatic reducing valve, which is here illustrated. 
 
 This reducing valve, the latest pattern of which is 
 shown in Fig. 1, is fastened by the bracket at x to the 
 coach frame (see Fig. 6) and connected to the brake 
 cylinder by suitable piping at z (see Fig. 2). When the 
 air enters the cylinder at the time brake's are applied, it 
 
TO B*AK« 
 
 HIGH SPEED BRAKE AUTOMATIC REDUCING VALVE 
 
 TOR PASSENGER EQUIPMENT C\R3 AND UJCOMOTIVES. " 
 
 Plate F 45, (1898 Pattern). 
 
 Am<iuia«y St»W»W» 
 
 Fifl.6 
 
166 
 
 OPERATION OF REDUCING VALVE 
 
 also comes in on top of piston 4. This piston is held up 
 by the spring 11 against a pressure of 60 pounds per inch, 
 if no more than 60 pounds conies into the cylinder the 
 reducing valve remains stationary in the position shown 
 in Fig. 3. 
 
 It should be noted that the area of the reducing valve 
 piston 4 that the brake cylinder air presses against is 
 slightly less when the gasket 20 is up solid to the shoulder 
 of the bushing e than after it is moved down. 
 
 When a graduated service application is made, if the 
 brake cylinder pressure raises above 60 pounds the piston 
 4 is moved down far enough to open the triangular port 
 b in the slide valve 8 to exhaust port a in the seat so 
 that the widest part of port b is open as shown in Fig. 4. 
 Air can then pass out of brake cylinder about as fast as 
 it comes in through graduating valve of the triple ; when 
 
 Fig 4. 
 
 position of ports, 
 service STOP 
 Pressure Exceeding 60 Pounds 
 in Brake Cylinder. 
 
 brake cylinder pressure drops below 60 pounds the spring 
 under piston 4 moves slide valve 8 up and laps ports a 
 and bj as shown in Fig. 3, and no more air can escape. 
 In case an emergency application is made the brake 
 cylinder pressure rises like a flash up to 85 pounds, piston 
 
OPERATION OF REDUCING VALVE 167 
 
 4 is forced down at once against the tension of the spring 
 to the lower limit of its travel into the position shown 
 in Fig. 5. This pulls slide valve 8 clear down, the small 
 end of the triangular port b is open to port a, and brake 
 cylinder air escapes slowly to atmosphere. As pressure 
 is reduced spring 11 has power to move piston 4 up and 
 the triangular port b opens wider, which reduces the 
 brake cylinder pressure faster, down to 60 pounds ; at 
 which point the slide valve is moved up to lap ports a 
 and b so no more air can escape from brake cylinder ; 
 this position is shown in Fig. 3. 
 
 The size of this exhaust port b has been determined 
 by experiments so as to reduce the brake cylinder pressure 
 proportionate to the reduction in speed. It is a different 
 size for each size of reducing valve to suit the different 
 volumes of air which should pass out of small and large 
 cylinders in about the same time. 
 
 With a service application the reducing valve reduces 
 the brake cylinder pressure only, as the triple valve closes 
 the air port from the auxiliary. With an emergency 
 application where the brake pipe pressure drops below 60 
 pounds the triple holds the air port open and the reducing 
 valve has to reduce both brake cylinder and auxiliary 
 volumes to 60 pounds. 
 
 When the brake is first set with emergency at a high 
 speed the pressure is about 85 pounds in the cylinder; 
 as the speed of the train is reduced by the action of the 
 brakes, the pressure is also reduced by the reducing 
 valve at about the same rate, till it reaches 60 pounds, 
 where it remains till the brake is released in the regular 
 way. 
 
 After an emergency application the reducing valve 
 lowers the cylinder pressure very slowly at first through 
 the small pointed end of the port b, and faster as the 
 pressure drops till it reaches 60 pounds, when the valve 
 closes. The speed of the train is reduced by the action 
 of the brakes slowly at first, and the reduction of speed 
 is more marked each succeeding second of time till when 
 
168 OPERATING THE HIGH SPEED BRAKE 
 
 nearly at a stop the speed is reduced very fast. The 
 pressure is reduced at about the same ratio as the speed, 
 so as to have it reach 60 pounds at about the time when 
 60 pounds will do the work properly. 
 
 This gives a very high brake power ready to use if 
 found necessary at high speeds and still leaves the service 
 application feature unchanged, ready for use in ordinary 
 stops. With the service application the reducing valve 
 remains in position as shown in Fig. 3. A reduction of 
 20 pounds from 110 applies the brake fully, as this 
 reduction will fill the brake cylinders at 50 pounds, the 
 full pressure of an ordinary service application; as well 
 as leaving a high auxiliary reservoir pressure of 90 pounds 
 ready for two more full service applications of the brake 
 if found necessary before re-charging; during these 
 moderate service applications the reducing valve does 
 not move. 
 
 The brake pipe and auxiliary pressure is set at 110 
 pounds with this type of brake — it may be more if the con- 
 ditions seem to call for it. As the engines equipped for 
 drawing these high speed braked trains may be used to 
 draw coaches without the high speed attachments, some 
 arrangement is needed for changing the standard brake 
 pipe pressure from 110 pounds to the lower pressure and 
 vice versa. For this purpose there are two feed valve 
 attachments on the engine. One of them is* set at 70 
 pounds, the other at 110, and there is a reversing cock 
 between them which can be turned to cut-in either one 
 for service as is desired, only one being operated at a 
 time. This reversing cock and valves are coupled to the 
 brake valve with suitable piping. The B-6 feed valve 
 can be used instead of the reversing cock and two feed 
 valves. There is a duplex governor for the air pump, 
 one side of which is set for 90 pounds main reservoir 
 pressure, for the ordinary 70 pounds brake pipe pressure, 
 the other side set at the higher pressure required, and a 
 cock to cut out the 90 pound side when using the higher 
 pressure. Ten pounds excess has been found sufficient 
 
OPERATING THE HIGH SPEED BRAKE 169 
 
 with a short train, but more is needed with a longer 
 train ; in some cases 30 pounds, in order to be sure to 
 release all brakes, after a light application. The tender 
 is equipped with a quick-action triple and reducing valve 
 the same as a coach. An engine truck brake is a neces- 
 sary part of this equipment, which is supplied with air 
 from the driver brake triple ; a reducing valve similar to 
 the coaches is used, set at 50 pounds. Any extra coaches 
 placed on these high speed braked trains require a reduc- 
 ing valve, although a safety valve set to blow of! at 60 
 pounds through a restricted opening can be used tem- 
 porarily by screwing it into the oiling plug hole in the 
 cylinder head. This safety valve is not as reliable as 
 the reducing valve, and is only used as a temporary 
 relief. 
 
 This type of brake will stop a train running at sixty 
 miles per hour in about 450 feet, less distance than the 
 ordinary quick-action brake with 70 pounds. 
 
 In making a graduated service application, with a 
 pressure of 60 pounds in the brake cylinder, when a 
 further service reduction of brake pipe pressure is made, 
 the cylinder pressure will increase but slightly above 60 
 pounds and immediately be reduced to that amount unless 
 a full continuous service reduction is made, in which 
 case the pressure may rise to 77 or 80 pounds, being 
 soon reduced to 60 pounds by the reducing valve. After 
 a cylinder pressure of 60 pounds is obtained, a full 
 service reduction to below 60 pounds should never be 
 made, except at high speeds in an emergency. 
 
 A high speed brake train is handled in the same 
 manner an expert engineer handles an ordinary passenger 
 train of the same length. Remember 'that air at 110 
 pounds pressure moves through the air ports more rapidly 
 than at 70 pounds, so when listening to the sound of the 
 air discharging from the preliminary and brake pipe 
 exhausts watch the gage closely. To make the brake 
 valve reduction more gradual a larger brake valve reser- 
 
170 HIGH SPEED BRAKE PRESSURES 
 
 voir is now used, which holds about 812 cubic inches. 
 The older ones hold close to 600 cubic inches. 
 
 A 20 pound service reduction will give about the same 
 brake cylinder pressure from 110 pounds that it does 
 from 70, i. e., about 50 pounds. 
 
 A 22 pound service reduction will give close to 60 
 pounds in the cylinder, anything over that may be wasted, 
 as the reducing valves will not let the cylinder pressure 
 rise above 60 pounds. 
 
 With 110 pounds on the back of the slide valve at the 
 beginning of a service application and 90 pounds at the 
 time of a release, the slide valve cannot be moved as 
 easily ■ by the triple piston as when the pressures are 70 
 and 50 pounds, and it will take more change of pressures 
 each side of the triple piston to move it. 
 
 Triple valves, when dirty, or when they need oiling, 
 give more trouble with 110 pounds than with 70, on 
 account of the increased pressure on the slide valve which 
 makes them more apt to work quick-action with a gradual 
 service reduction. For that reason both the triple valves 
 and brake valve must be kept clean and well oiled and 
 good stiff excess is needed with a long train. 
 
 When coupling to a train having 110 pounds brake pipe 
 pressure with an engine carrying 70 and 90 pounds, put 
 the brake valve on lap and leave it there till the 110 
 pounds pressure has blown down to 70 pounds and the 
 reducing valves on the cars have blown down to 60 
 pounds. Then with full excess go to full release and 
 the brakes should all release. With L triples it is neces- 
 sary to carry the high pressure on the engine to release 
 the brakes. 
 
 In handling any very long passenger train a straight 
 air brake on the engine and tender is a valuable aid in 
 preventing break-in-twos or serious shocks when releasing 
 at a slow speed, the ET equipment on the* locomotive is 
 still better. 
 
 Unless an emergency arises requiring a very sudden 
 stop, do not use the emergency application with 110 
 
USE OF EMERGENCY 171 
 
 pounds, when running at a slow speed, say below twenty- 
 five miles an hour. Unless the rail conditions are perfect 
 the wheels are apt to slide ; this will increase the length 
 of the stop. When an emergency, such as danger to life 
 or property, confronts you, remember that all the brakes 
 act quickly with the emergency application — in less than 
 three seconds — which they will not do as quickly with a 
 service application. Difference in piston travel does not 
 affect the work of the high speed brake as much as it 
 does the 70 pound brake with full service applications. 
 As soon as the reducing valve operates it equalizes the 
 cylinder pressures for long and short travels, for all will 
 reduce to the same final pressures. If the leverage is 
 proper, all cars will be braking alike. One of the best 
 preventives of wheel sliding is equal and maximum brake 
 power on all the cars, tender and engine. With all wheels 
 holding back alike tests show that wheel sliding is rare. 
 
PLATE F.+8 
 
 HIGH PRESSURE CONTROL 
 
 With the heavy capacity cars now in general use, the 
 empty weight of the car on which the braking power is 
 calculated is such a small proportion of the full loaded 
 weight that some provision must be made to increase the 
 braking power on the loaded cars. This is particularly 
 the case with coal and ore cars, which usually run empty 
 to the mines and return loaded. For this class of cars a 
 two-pressure system has been devised in which a moder- 
 ately low pressure of 55 to 65 pounds is carried in the 
 brake pipe and auxiliaries of the empties, 
 while with the loaded trains 90 pounds 
 can be carried and thus increase the brake 
 power about 50 per cent. The duplex 
 governor and reversing cock which is part 
 of the High Speed Brake is used with the 
 High Pressure Control, but the duplex 
 governor is piped a little different. There 
 are two separate pipes leading to the gov- 
 ernor,, one from the main reservoir to the 
 side of the governor set for the highest 
 pressure, the other pipe leading from the 
 left side of the reversing cock, which is 
 set for the lowest pressure, to the low 
 pressure side of the governor, so that when 
 the low pressure feed valve is cut in, the low pressure 
 governor is also cut in. 
 
 When handling a train of empties going up hill the 
 low pressure is used, coming down hill with a train of 
 loads the high pressure is used, and thus the train can be 
 controlled. Any empty cars in the train must have the 
 air brake cut out at cross-over pipe when using the high 
 pressure to avoid sliding wheels ; unless the caboose has 
 a safety valve, it must be cut out also. 
 
 A safety valve shown on this page is attached to the 
 brake cylinders of the engine and tender. This same type 
 of valve is also used on any extra coaches set in a High 
 Speed Brake train. 
 
 !k*"S 
 
 SAFETY VALVE. 
 
THE AMERICAN AUTOMATIC SLACK ADJUSTER 173 
 
 
THE AMERICAN AUTOMATIC SLACK ADJUSTER 
 
 The illustrations of the American Brake Co.'s Auto- 
 matic Slack Adjuster show how the adjuster cylinder 
 and adjusting screw is attached to the brake cylinder and 
 dead cylinder lever. A small port is drilled and tapped 
 in the brake cylinder at the point a, which is to be the 
 limit of the running piston travel. A pipe e is connected 
 from this port a to the adjuster cylinder at G. 
 
 The brake piston acts as a valve to admit air to the 
 adjuster cylinder. When it moves beyond port a during a 
 brake application, air from behind brake piston passes 
 out of port a through pipe e into the slack adjuster 
 cylinder, pushes the piston to the left against the strength 
 of the coiled spring, carrying the pawl out; the flat spring 
 pushes the pawl down, hooking it down over a tooth of 
 the ratchet nut. When the brake is released, air in the 
 adjuster cylinder passes out, spring then returns the 
 adjuster piston to its normal position which pulls back 
 pawl; this rotates ratchet nut on the screw attached to 
 the dead cylinder lever fulcrum jaw, moving the end of 
 the lever up 1/32 of an inch, taking up some slack in the 
 brake rigging. The slack is not taken up when the brake 
 is applied, but after it is released, when there is no strain 
 on the cylinder lever. When the coiled spring pushes 
 back the piston and pulls the pawl, the lug strikes the 
 stop, this raises the pawl out of the ratchet, so that the 
 ratchet nut can be turned either way, if the adjuster 
 piston is in normal position, this will allow nut to be 
 turned by hand to let out or take up slack in brake rig- 
 
OPERATING THE SLACK ADJUSTER 175 
 
 ging when new shoes are put on, or repairs made to brake 
 gear. In case the ratchet nut is turned on its screw till 
 the jaw is pulled up solid against the adjuster cylinder, 
 in the older type, the pawl cannot be moved far enough 
 by the spring to have the lug strike the stop; in which 
 event the casing must be opened up and the pawl raised 
 out of the ratchet nut, so it can be turned by hand. A 
 later type of American Adjuster has a stop screw located 
 near the adjuster cylinder, so arranged that the jaw comes 
 in contact with it instead of the cylinder; by removing 
 this screw and turning the ratchet by hand the pawl is 
 released. A still later type has a tap bolt in the end of 
 the the adjuster nut casing, slack off this tap bolt and the 
 screw will turn a little more and release the pawl. The 
 pawl and ratchet are enclosed in a tight case to keep out 
 ice and foreign matter which would prevent their 
 movement. 
 
 In case the brake piston does not travel to port a the 
 adjuster does not move any of its parts, but is at rest. If 
 port a is partially or fully opened by the piston, which 
 acts as a valve, compressed air is admitted to the adjuster 
 cylinder, so it is operated. 
 
 Slack adjusters take up the travel beyond a certain 
 running travel limit. The brake piston will travel farther 
 on a running car than one standing still, because the 
 journals and bearings will be crowded to one side of the 
 oil boxes and all lost motion that can be taken up in the 
 truck comes out when running. For that reason the 
 piston travel is usually found to be less when measured 
 at a standing test than the actual distance of the port a 
 from the pressure head of the cylinder. If this port a 
 is eight inches from the head to allow eight inches travel 
 it is not unusual to find the travel at a standing test, less 
 than six inches. When locating port a first see how far 
 the edge of the piston packing leather is from pressure 
 head x. Port a is very small where it comes through the 
 wall of the cylinder, so that the piston packing leather 
 will not be cut when passing over the opening. 
 
176 TAKING UP THE SLACK 
 
 The amount of slack depends on the brake leverage. 
 For instance, a 10-inch brake cylinder has a power of 
 4,700 pounds. If it is used on a coach weighing 52,220 
 pounds, 90 per cent of this weight is 47,000 pounds, so 
 the brake power required at the shoes is ten times that at 
 the piston, or a total leverage of 10 to 1. With a car 
 weighing 36,550 pounds the brake power would be 32,900 
 or a total leverage of 7 to 1. Now with the same amount 
 of slack on the shoes of each car one car would have 10 
 inches piston travel, the other would have only 7 inches. 
 With a leverage of over 10 to 1 you cannot restrict the 
 piston travel to 6 inches and have the shoes clear the 
 wheels so the coach will pull easy between the stations. 
 
 One of the errors made when taking up slack by hand 
 is using shoe clearance instead of piston travel as a guide. 
 With a light car and large cylinder, where the total 
 leverage is low, there will be considerable clearance in 
 proportion to the piston travel. If the slack is taken 
 up the same as for a car of heavy leverage, the brake 
 piston will not pass over the leakage groove with mod- 
 erate service applications. On the other hand, with a 
 heavy car, the piston may bottom on the cylinder head. 
 For this reason a device that will regulate the piston 
 travel while the train is under way will do better work 
 than hand regulation. 
 
 Uniform piston travel is one of the prerequisites of 
 good brake service. When this can be automatically main- 
 tained during an entire trip it ensures a uniform as well 
 as a maximum efficiency of the brakes. If this adjustment 
 is made by hand the piston travel varies considerable on 
 a long trip with a corresponding loss of efficiency. 
 
 Unequal piston travel is the cause of a good many 
 slid flat wheels in coach equipment, and is responsible for 
 most of the break-in-twos in long freight trains. The 
 braking power is increased by short travel and reduced 
 by long travel, so that a coach with short travel may 
 have power enough to slide the wheels when the other 
 cars do not skid. 
 
BRAKE LEVERAGE 
 
 Ability to figure up brake leverage is an accomplish- 
 ment for an air brake operator — not always a necessity — 
 it pays to know something definite about it. The rules 
 are not complicated and formulas help to shorten the 
 calculations. You should first learn how the several 
 classes of levers operate and the difference between those 
 of the first, second and third kind. A lever of the first 
 land has the power applied at one end, the weight to be 
 moved is at the other end and the fulcrum which takes 
 "both the strain of the power and the resistance of the 
 weight is in between the ends; in the cut of a lever of 
 the first kind F is the force or power coming from the 
 top rod, C in the middle is the fulcrum and W at the 
 "bottom is the brake beam or weight to be moved. The 
 cylinder lever connected to the brake piston is of the first 
 kind. A pinch bar when we pry down on the rail and 
 against the tire of a driving wheel is a good illustration 
 •of this class of lever. 
 
 A lever of the second kind has the power F applied at 
 one end, the fulcrum C is at the other and the weight or 
 "brake beam to be moved is between them at W ; the live 
 lever of an outside hung brake is usually of the second 
 kind. If you use the pinch bar by passing it under the 
 object to be moved, resting one end on the ground and 
 lifting up on the other it will show you the second kind. 
 
 With a lever of the second kind the weight W takes 
 as much strain as both the power F and fulcrum C. A 
 lever of the third kind has the power F attached between 
 the ends W and C; a lever of this class takes more power 
 in proportion to the weight to be moved than either of the 
 other kinds. With any class of lever the strains at the 
 ends added together equal the strain in the middle. So 
 you see the power developed by any one of three kinds of 
 levers of the same length depends on the relative positions 
 •of the power, weight and fulcrum. 
 
 When you make measurements and calculations of 
 
CALCULATING BRAKE LEVERAGE 
 
 179 
 
 brake power, in case the pins or brake jaws are much 
 worn set the brake by hand and measure the levers 
 carefully as a mistake of a very short distance on the 
 short end of a live lever will alter the power considerable. 
 Always multiply the power or force in pounds by the 
 distance in inches from the point F where power is 
 attached to the fulcrum C, and divide this product by the 
 distance in inches from fulcrum C to brake beam W. 
 
 — FORMULA — 
 
 F 
 
 LEVER or LtKIND 
 
 LEVER or2no KINO LEVER or 3rd KINS 
 
 On page 177 is a small cut of the arrangement of 
 levers for a coach brake with Hodge system which we 
 will use to illustrate this explanation. 
 
 Beginning at the brake cylinder where the power is 
 first exerted, the pressure at F where the piston is 
 attached to live cylinder lever is 4,700 pounds for a 10-inch 
 cylinder with quick-action triple. This lever being of the 
 first kind with fulcrum C between the ends, we multiply 
 the power 4,700 by 12, the distance to the fulcrum C, and 
 
180 CALCULATING BRAKE LEVERAGE 
 
 divide this product by 11 J A, the distance from the fulcrum 
 to W, the Hodge lever rod connection, and have 4,900 
 pounds strain on this rod which goes to the Hodge lever 
 at X. This is a lever of the third class and being equally 
 divided, each end gets half this power or 2,450 pounds, 
 which is the force at the top end of the live truck lever. 
 We next multiply 2,450 by the distance on this lever from 
 F to C, 36 inches, and divide this product by 8, the distance 
 from C to W, and we have 11,000 pounds, the strain on 
 the brake beam. A shorter way is to multiply the pull 
 at top end of live lever 2,450 pounds, by 4}^, the propor- 
 tion of the live lever. To get the proportions of a live 
 lever, divide the total length between the centers of out- 
 side pin holes at F and C by the distance from C to W — 
 called the short end — in this case 8 into 36 or 4*^ to 1. 
 If the force at F is 2,450 pounds and the strain at W is 
 11,000 pounds, the resistance at C will be 8,550 pounds, 
 as the sum of the strains at both ends of a lever must 
 balance the strain in the middle. This strain of 8,550 
 pounds on the bottom rod goes to the bottom end of 
 the dead truck lever at F and is to be multiplied by the 
 distance from F to C — the outside length of dead lever — 
 and the product divided by the distance from C at the top 
 end of dead lever to W the brake beam connection; if the 
 dead lever is the same proportion as the live one the 
 result will be 11,000 pounds. 
 
 Now going back to the cylinder levers, the tie rod has 
 a strain of 9,600 pounds which is the sum of 4,700 and 
 4,900, the strains on both ends of the live cylinder lever. 
 This strain goes to the point F in the floating cylinder 
 lever which is shown fulcrumed at C on the cylinder head 
 and its free end W connected to the Hodge rod for the 
 floating lever at the other end of the car and from there 
 the power goes to the live and dead truck levers of the 
 other truck as already explained. 
 
 By this arrangement of levers we get a braking power 
 on each end of the car equal on both trucks, with a total 
 amounting to twice what the brake piston has; but we get 
 
CALCULATING BRAKE POWER 181 
 
 it because the piston travels twice as far as it would if the 
 fulcrum C in the live cylinder lever was fixed stationary; 
 both cylinder levers move and the piston travels far 
 enough for the two. 
 
 Both cylinder levers need not be of the same length, 
 but they must be of the same proportion if the same strain 
 is to go to each end of the car. Coaches have cylinder 
 levers exactly alike for each end of the coach; freight cars 
 do not, although they are the same proportion. 
 
 In making calculations for braking power for coach 
 equipment, take 90 per cent of the weight which the 
 wheels having brake shoes attached put on the rail under 
 them. With all wheels braked this means 90 per cent of 
 the weight of the coach when empty, a twelve wheel 
 coach with only eight wheels braked takes 8/12 of the 
 weight as a basis for calculation. Use 70 per cent of 
 the light weight of any freight car used in interchange 
 service ; while 100 per cent of the light weight, of a 
 tender is generally used, a tender usually has a supply 
 of water, fuel and tools which hold its weight up above 
 the skidding point. The light weight of cars and coaches 
 is used when making leverage calculations to keep the 
 brake power below the limit at which the wheels will 
 slide when the brake is operated on an empty car. If the 
 brake cylinder receives its supply of air from the auxiliary 
 only, as is the case with the plain triple valve and some 
 of makes of quick-action triples, use 50 pounds as the 
 equalized piston and auxiliary pressure. If part of the 
 supply comes from the brake pipe, as is the case with 
 the Westinghouse quick-action triple, use 60 pounds. 
 
 Driver brake leverage is 75 per cent of the weight at 
 the rail; an engine truck brake should have less than that, 
 as there is no way to get sand to the rails for the truck 
 wheels on slippery track. 
 
CAM DRIVER BRAKE LEVERAGE 
 
 The limited space in this book will not allow a full 
 description of how the cams and levers are designed, but 
 some information on calculating their brake power will 
 come handy to the men operating them. The illustration 
 of the cam brake shows its various parts. 
 
 CAM SC/f£tV PIN 
 
 FORMULR. 
 
 *-«* 
 
 These cams are really segments of wheels with x-x for 
 the centers. If they are properly laid out no matter how 
 far they roll down, the point of contact at the edges of the 
 wheels will always be on the line between the centers x-x. 
 
 The cam as used with the brake is a bell crank with 
 the long arm from g to x and the short arm from x to a. 
 A true bell crank requires a fixed fulcrum at x to act as a 
 brace to transmit the power at g to a, but in the case of 
 the cams no fulcrum is needed there, for the faces of the 
 cams rolling against each other act as fulcrums. 
 
CAM DRIVER BRAKE LEVERAGE 183 
 
 To calculate the brake power, set the brake full on and 
 measure the distance between the cam link pins at a-a. 
 Also measure the distance between the cam link pins g-g 
 and subtract this distance from the distance a-a; one-half 
 of this remainder will be the long arm of the bell crank 
 included in the design of each cam, which distance we will 
 call X in the formula. We do not measure clear to the 
 face of the cam, because the power is applied at g-g } 
 one-half of the power exerted by the piston going to 
 each cam. 
 
 As the cams roll down against each other when the 
 brake is set their faces touch at one point only, which we 
 will call the point of "rolling contact." Place a straight 
 edge from one of the cam screw pins at a t to the other, 
 on a line with their centers and measure from the straight 
 edge up to the point of rolling contact; this distance is the 
 other arm of the bell crank, it is called the "offset," and 
 is the distance from a to x also ; this is named O in the 
 formula. This last distance divided into the length of the 
 line from b to a — the long arm of the bell crank — gives 
 the leverage of the cam. 
 
 Multiply this leverage by 1,250 for an 8-inch cylinder 
 or by 2,000 for a 10-inch cylinder, which will give the 
 power delivered at the bottom end of the lever at a. 
 Multiply this power by the whole length of the lever from 
 a to k, called Z in the formula, and divide the product by 
 the distance from the pin k to the pin i the brake shoe 
 head, which is distance Y ; this quotient is the brake power 
 delivered at that shoe; four times the power for one shoe 
 will be the brake power for all shoes, which should be 75 
 per cent of the weight on drivers. In all these calcula- 
 tions we use 50 pounds as the air pressure per inch on 
 the brake piston. 
 
 To calculate the other way, take 75 per cent of the 
 weight on the rail at the drivers, one-fourth of that will 
 be the power required at each shoe. Multiply this amount 
 by the length in inches of the lever from i to k and divide 
 
184 CAM DRIVER BRAKE LEVERAGE 
 
 the product by the length from k to a; this last amount 
 will be the power required at a, delivered by the cam. 
 
 Divide this by 1,250 for an 8-inch cylinder or by 2,000 
 for a 10-inch cylinder, the quotient will be the "leverage'' 
 of the cam, and should correspond exactly with the. cam in 
 use. To get the leverage of the cam, divide the length at 
 X by the offset. 
 
 The cams are designed to give the full brake power of 
 75 per cent of the weight on drivers when the shoes and 
 tire are worn down to their limit. The brake power 
 increases as the length of the cam X is increased by wear 
 of shoes and tires, but this does not affect the "offset" O. 
 Therefore, with thick new tire and new shoes you will not 
 get the full brake power, because the long lever of the bell 
 crank in the cam is not the full length as laid out for a 
 thin tire. To avoid the difficulty of having too much 
 leverage with thin tire the radius of the face of the cam 
 is struck from a point one and one- fourth inches further 
 out than at x. A thick or thin shoe does not change the 
 power as much where the cams are long with long wheel 
 base as with very short cams. 
 
 If you find that with a short piston travel, say two 
 inches, the cams do not roll down so that their faces 
 separate at the lower corners, as shown in the illustration, 
 the cam links are too short. It is not unusual to find 
 these links put up too short, and this defect reduces the 
 brake power very materially. Changing the brake heads 
 and putting on a wide one in the place of a narrow head 
 also reduces the brake power, as it shortens the length of 
 the cam. A thick shoe reduces the power the same way. 
 
 In any brake the proportion between the piston travel 
 and the brake shoe travel is the leverage. For instance, if 
 the piston travel is four inches and the brake shoes travel 
 one-half inch, the proportion is eight to one, so the power 
 from the piston is multiplied eight times. If you can get 
 the exact brake shoe travel of a brake and divide it into 
 the piston travel you can easily rind the brake power. 
 
X 
 
 cd 
 
 u 
 
 V 
 
 x 
 
 u 
 
 +J 
 
 73 
 
 u 
 
 cd 
 
 <D 
 
 > 
 
 - 
 
 
 
 <u 
 
 <L> 
 
 c 
 
 fli 
 
 > 
 
 ^C 
 
 <y £ 
 
 ed 
 
 
 X 
 
 o 
 
 
 o 
 
 73 
 
 P 
 
 
 X 
 
 
 be 
 
 X 
 
 5 
 
 
 cd 
 
 
 — 
 
 73 
 
 ft 
 
 
 a 
 
 
 cd 
 
 E 
 
 o 
 
 
 ^ 
 
 
 X 
 
 c 
 
 o 
 
 
 cd 
 
 n 
 
 
 15 
 
 :- 
 
 I 
 
 o 
 
 o 
 
 T- 
 
 
 U 
 
 
 73 
 
 
 1h 
 
 x 
 
 o ^ 
 
 e 
 
 
 cd 
 
 CO 
 
 u 
 C 
 
 M-l 
 
 
 
 j3 
 
 73 
 
 <u 
 
 X 
 
 Ih 
 
 
 
 p 
 
 u. 
 
 X 
 
 ft 
 
 
 ft 
 
 cd 
 
 <L> 
 
 
 
 P 
 
 
 
 X 
 
 ^3 
 
 73 
 
 g 
 
 o 
 o 
 a 
 
 C 
 
 c 
 
 cd 
 P 
 
 •^ 
 
 y£3 
 
 c5 
 
 X 
 
 
 
 cd 
 
 
 CQ 
 
 
 
 
 Ih 
 
 X 
 
 <D 
 
 X 
 
 u 
 
 S" 
 
 X 
 
 & 
 
 
 u 
 
 cu 
 
 '-5 
 
 < 
 
 cd 
 
 Ih 
 
 
 Ih 
 
 c 
 
 o 
 
 73 
 
 ^ 
 
 +J 
 
 Mh 
 
 . ~ 
 
 g 
 
 <L> 
 
 <U 
 
 o 
 
 be 
 
 -x 
 
 ri 
 
 > 
 
 £ 
 
 <|H 
 
 c~ 
 
 
 
 GJ 
 
 
 
 
 
 x 
 
 
 
 X 
 
 »* 
 
 c 
 
 Ih 
 
 
 
 
 o 
 
 cd 
 
 
 EU 
 
 Ih 
 
 
 o 
 
 s- 
 
 *-<- 
 
 > 
 
 CJ 
 
 
 bo wc 
 
 o 
 
 cu 
 
 TT 
 
 X 
 
 
 
 
 
 
 cu 
 
 
 
 
 •4H 
 
 o 
 
 "Pi 
 
 c 
 be 
 
 X 
 
 73 
 Ih 1 
 
 4- 
 
 '> 
 
 s 
 
 U 
 
 MH 
 
 X 
 
 73 
 
 
 
 X 
 
 o 
 
 <D 
 
 u 
 
 c 
 
 P 
 
 ft 
 
 U 
 
 X 
 X 
 
 73 
 
 5 
 
 
 
 ft 
 
 o 
 o 
 
 © 
 
 7t 
 
 ft 
 Ih 
 
 b£ 
 
 E 
 
 o 
 o 
 a 
 
 o 
 
 u 
 
 <D 
 ft 
 
 cd 
 
 'i 
 
 
 
 o 
 
 O 
 cd 
 
 73 
 
 u 
 
 73 
 
 ^ 
 o 
 
 £ 
 
 x 
 
 ^ 
 
 4J 
 
 X 
 
 *> 
 
 
 £ 
 
 u 
 
 c^ 
 
 "*■"' 
 
 '-5 
 
 p 
 
 C 
 
 'So 
 
 P 
 
 •a 
 
 >> 
 
 
 *ac 
 
 
 73 
 
 ^ 
 
 cd 
 
 — - 
 U 
 
 cu 
 
 73 
 
 u 
 
 o 
 
 X 
 
 '> 
 
 '-5 
 
 > 
 eg 
 
 P 
 
 <u 
 
 ft 
 
 
 
 
 X 
 
 <J 
 
 > 
 
 z 
 cd 
 
 o 
 
 o 
 
 C 
 
 X 
 X 
 
 Ih 
 
 O 
 > 
 
 o 
 P 
 P 
 C 
 
 
 a) 
 
 u 
 cu 
 
 <D 
 
 1 
 
 X 
 
 u 
 
 E 
 
 cd 
 u 
 
 
 1 
 
 
 pq 
 
 H 
 
CALCULATIONS FOR AIR PRESSURES 
 
 To calculate at what finail pressure two separate 
 volumes of air at different pressures will equalize when 
 connected so air will flow from the higher to the lower 
 pressure, it is necessary to reduce the volumes and press- 
 ures to one standard of comparison. 
 
 Suppose that a reservoir has a volume of 1,620 cubic 
 inches with a gage pressure of 70 pounds per inch. If 
 that same air was expanded to one pound gage pressure 
 per inch it would occupy seventy times as much space or 
 70x1,620, which is 113,400 cubic inches at one pound press- 
 ure. We will call this amount cubic-inch-pounds, all 
 volumes and pressures can be reduced to this standard. 
 
 A gage shows the pressure above the atmospheric 
 line, but absolute pressure begins at the vacuum line; to 
 get absolute pressure we add fifteen pounds to the press- 
 ure shown on the gage, before the calculations are made 
 and subtract fifteen pounds from the result to get back 
 to the gage pressure again. If the calculations refer to 
 volumes which contain air at or above the atmospheric 
 pressure, this fifteen pounds need not be taken into 
 account. If any question of piston travel is connected with 
 it, the fifteen pounds must be considered. 
 
 We will take the case of a main reservoir of 16,000 
 cubic inches at 90 pounds, and an empty brake pipe of 
 twenty-five cars which have the same volume. Multiply 
 main reservoir volume by its pressure and divide the 
 product by the combined volume of both reservoir and 
 brake pipe. 16,000x90=1,440,000 cubic-inch-pounds, this 
 divided by 32,000 gives 45, the gage pressure at equaliza- 
 tion. 
 
 Suppose this brake pipe instead of being empty has 40 
 pounds gage pressure in it, and the main reservoir 90; 
 40 pounds in the brake pipe will be 640,000 cubic-inch- 
 pounds, this added to the amount in the reservoir and 
 the sum divided by the combined volumes will give sixty- 
 five as the pressure at equalization. 
 
CALCULATIONS FOR AIR PRESSURES 187 
 
 A retaining valve is holding 15 pounds in the brake 
 cylinder. After charging the auxiliary to 70 another full 
 application is made, we can figure the equalizing pressure 
 as follows : 450 cubic inches at 15 pounds is 6,750 cubic- 
 inch-pounds. The auxiliary at 70 holds 113,400 cubic- 
 inch-pounds, the total amount in both is 120,150 cubic- 
 inch-pounds, which now expands into the total volume of 
 1,620 plus 450 or 2,070 cubic inches. Divide the full 
 amount of air by the total space and we have 58 pounds. 
 We do not figure from the vacuum line in this case. 
 
 When calculating the pressure at which the brake 
 cylinder and auxiliary will equalize when the piston moves 
 out, remember that there is no atmospheric air in the 
 space left by the piston in moving out and this space must 
 be filled with air from the vacuum line of absolute press- 
 ure, so we must add 15 pounds to the gage pressure of 
 70 pounds, which gives 85 pounds. 
 
 The auxiliary holds about 1,620 cubic inches at 85 
 pounds, this is 137,700 cubic-inch-pounds absolute pressure. 
 The volume of an 8-inch brake cylinder with 8 inches 
 travel, including clearance and piping from the triple, is 
 close to 450 cubic inches ; the combined volume is 2,070 
 cubic inches. Divide 137,700 by this combined volume 
 and subtract fifteen from the quotient, you will then have 
 the equalizing pressure, about 51.5 pounds. 
 
 To find how much brake cylinder air at 60 pounds 
 comes from the brake pipe with an emergency application 
 and how much from the auxiliary, proceed as follows: 
 The brake cylinder volume of 450 cubic inches at 75 
 pounds absolute pressure is 33,750 cubic-inch-pounds. The 
 auxiliary of 1,620 cubic inches loses 10 pounds, from 
 70 down to 60; this is 16,200 cubic-inch-pounds from the 
 auxiliary; this subtracted from 33,750 leaves 17,550 cubic 
 pounds to come from the brake pipe. Divide 17,550 by the 
 volume 450 cubic inches we have 39 pounds absolute press- 
 ure; subtracting 15 pounds to get gage pressure we have 
 24 pounds as the part the brake pipe supplies; this varies 
 
188 PRESSURE WITH PARTIAL APPLICATION 
 
 with the piston travel and condition of strainers, it is 
 usually less than this. 
 
 When you make a partial application of the brake and 
 want to know what brake cylinder pressure will result 
 from any certain reduction in the auxiliary, proceed as 
 follows : Say we make a 10 pound reduction. If the 
 volume of the auxiliary is 1,620 cubic inches, at 10 pounds 
 per inch the total amount passing from the auxiliary to 
 the brake cylinder would be 16,200 cubic-inch-pounds. In 
 this calculation we will allow for the air contained in the 
 clearance space of the cylinder, the auxiliary tube between 
 the triple valve and cylinder, and the triple valve itself, 
 which amounts to an average of 47.92 cubic inches, which 
 contains air at 15 pounds per inch or close to 718 cubic- 
 inch-pounds. This added to the amount coming in from 
 the auxiliary makes 16,918 cubic-inch-pounds, and it will 
 equalize in the 450 cubic inches total volume of the brake 
 cylinder and clearance at 38 pounds absolute pressure, or 
 23 pounds gage pressure. You can calculate for any given 
 reduction the same way from any pressure; just as long 
 as you do not make a brake pipe reduction that will cause 
 the brake cylinder and auxiliary to equalize, or when you 
 do that it stops the auxiliary reduction. A 10 pound 
 reduction from 90 gives just the same pressure as at any 
 lower pressure till you reach the equalizing pressure, 
 which is usually below 50. The next 10 pound reduction 
 from the auxiliary into this cylinder of air having a 
 pressure of 23 pounds will show a greater proportionate 
 raise on the gage, for the first reduction had to fill the 
 cylinder from the vacuum line up to gage pressure — 15 
 pounds — the second one had this work done for it, and 
 therefore made a better showing on the gage. 
 
 When making tests the gage will not always show 
 these exact amounts, as the leakage groove uses consider- 
 able air, auxiliaries are not all the size specified, the clear- 
 ance in the end of cylinder varies, and the expansion of 
 air lowers the temperature, which alters the pressure. 
 
 The question of the fall of temperature is not taken 
 
SIZE OF RESERVOIRS 189 
 
 into consideration in these calculations, as the temperature 
 of the air in the brake equipment on a car is very close 
 to that of the atmosphere at all times. 
 
 To get the area of the piston, multiply the diameter by 
 itself and that product by .7854. To get the volume of the 
 cylinder, multiply this area by the piston travel and add 
 the clearance. This clearance consists of the space between 
 piston and pressure head, usually Y% of an inch, the pipe 
 between the triple and the cylinder and the space in the 
 triple valve that is filled with brake cylinder air. 
 
 Reservoirs are so constructed that it is difficult to cal- 
 culate their exact volume from their outside dimensions, 
 this can be obtained exactly by weighing them while 
 empty, then filling full of water and weighing again; the 
 difference in weight will be the amount of water contained. 
 A pound of water at 62 degrees occupies 27.71 cubic 
 inches ; one cubic foot weighs 62.355 pounds. 
 
 A cast iron auxiliary for an 8-inch freight brake holds 
 about 1,620 cubic inches. 
 
 10 x 24 in. wrought iron auxiliary 1.510 cubic in. 
 
 12 x 33 in. wrought iron auxiliary 3.030 cubic in. 
 
 14 x 33 in. wrought iron auxiliary 4.120 cubic in. 
 
 16 x 33 in. wrought iron auxiliary 5.322 cubic in. 
 
 The equalizing reservoir from 590 to 621 cu. in. the 
 later pattern 10 x 14^4 inches long, hold 800 cu. in. A 
 freight car has about 640 cu. in. in the brake pipe, hose, 
 cross-over pipe and triple valve to the bottom of the 
 triple piston — all this space contains brake pipe air. 
 
 Main reservoirs vary in size to suit their location on 
 the engine, when of sufficient volume there are usually 
 more than one, having the air from the pump passing 
 into the first one, from there to the next, and so on to the 
 brake valve. This gives the air a chance to cool down to 
 the normal temperature of the atmosphere, when it will 
 deposit all its moisture as water in the main reservoir. If 
 the air passes through the brake valve without cooling 
 down it will leave some of the water in the brake pipe — 
 
190 TEMPERATURE OF AIR DURING COMPRESSION 
 
 see question 8 — and give trouble in the operation of the 
 brake. 
 
 Main reservoirs should have a volume of at least 
 20,000 cubic inches. Freight engines should have 1,000 
 cubic inches capacity for each car in the train. An engine 
 that can handle a 75-car train should have 75,000 cubic 
 inches. Large main reservoir capacity is necessary to 
 promptly release all brakes on a long train and will in a 
 measure prevent stuck brakes and slid flat wheels on the 
 rear cars — see question 9. A large main reservoir also 
 tends to save a pump, as it can run at a slower speed, for 
 it can run continuously, not intermittently. 
 
 When air at a temperature of 60 degrees is compressed 
 from the atmosphere line up to a gage pressure of 70 
 pounds the temperature rises to about 400 degrees; with a 
 pressure of 90 pounds it is about 450 degrees, at 105 
 pounds it is 490 degrees. As this heat is the result of the 
 mechanical energy of the steam developed through the air 
 pump, you can readily see that it takes more power from 
 the boiler to reach a high pressure than a moderate one. 
 Also the air piston will come nearer the end of its stroke 
 before the air is compressed to 105 than at 90 pounds, so 
 that a less amount of 105-pound air is delivered than of 
 90. As the air usually cools off to the normal tempera- 
 ture before it passes into the brake cylinder, we can take 
 no advantage of any expansion of air by the heat of 
 compression. 
 
 The heat that is given out by compression is taken up 
 when the air is allowed to expand. When air expands 
 through any opening from a high to a low pressure it 
 takes up or absorbs heat from all surrounding bodies, this 
 accounts for its being so cool when coming out of the 
 bleed cock, exhaust port of a triple or exhaust pipe of an 
 engine run by compressed air, in some cases it will form 
 ice. 
 
 When studying the equalizing processes in the opera- 
 tion of compressed air equipment, remember that it is air 
 that flows from one part of the equipment to another and 
 
THE NEW YORK AIR BRAKE 191 
 
 not pressure. Pressure is a condition, air is a substance 
 or material. When air flows from the auxiliary to the 
 cylinder it will change the conditions or pressure in these 
 places, but the pressure does not flow either way. 
 
 It will take away much of the mystery of equalization 
 if you bear these facts in mind. 
 
 THE NEW YORK AIR BRAKE 
 
 The important parts of the New York Air Brake that 
 differ from those of the Westinghouse Automatic Brake, 
 are the Duplex Air Pump ; Governor ; Engineer's Valves ; 
 Compensating Valve; Quick- Action Triple Valve; Air 
 Signal Valve and Brake Pipe Strainer. The Brake Cylin- 
 ders and pistons in all their details; Reservoirs, both main 
 and auxiliary; Pressure Retaining Valves; Reducing Valve 
 for the air signal system; Brake Pipe with Hose Coup- 
 lings, Angle and Cut-out Cocks and Conductor's Valves 
 are the same in both systems of equipment; their con- 
 struction and operation have already been described in 
 this book. 
 
 As freight cars in interchange service are moved from 
 one railroad to another when of the same gage, there 
 will be in all freight trains some cars equipped with the 
 Westinghouse and others with the New York brake. The 
 Master Car Builders' specifications require that all brakes 
 in a train shall be so constructed that the different kinds 
 will operate in unison, so as to control the speed of the 
 train without shocks. For that reason the general rules 
 for the handling of trains are the same, whichever brake 
 is used. There are several differences in the construction 
 of these two kinds of brake equipment, that give different 
 results when they are operated; these points will be 
 explained later on. 
 
(Goverhor) 
 
 rPIPE 
 
 FROM BOILER 
 
 2DP55II 
 
 2DPI38 
 
 2DP59A 
 
 m IX* PIPE 
 
 TO EXHAUST 
 
 2DP58A 
 5DPI43 
 2 DP 142 
 2DPI4Q 
 
THE DUPLEX AIR PUMP 
 
 This pump has two steam cylinders, 1 and 2, and two 
 air cylinders, 3 and 4 ; the steam valves, 5 and 6, being 
 operated by reversing or tappet rods, 8-8. These tappet 
 rods are operated by the tappet plates 20, which are 
 securely fastened to the lower side of each steam piston 
 by bolts 55. The steam cylinders each receive steam from 
 the boiler and exhaust to the atmosphere, the air cylinders 
 each receive free air from the atmosphere; but the air 
 in cylinder 4 when compressed passes into cylinder 3 and 
 from there is forced into the main reservoir. Thus, the 
 air cylinders compound the air, while the steam cylinders 
 work simple. Each steam cylinder of the No. 2 pump is 
 7 inches in diameter and 9 inches stroke, the low pressure 
 air cylinder 4 is 10 inches in diameter, the high pressure 
 air cylinder 3 is 7 inches in diameter; both cylinders have 
 the same stroke as the steam cylinders, 9 inches. The 
 volume of air cylinder 4 is twice that of cylinder 3. 
 
 The sectional view shows the pump with all parts in 
 the position when making its first stroke after turning on 
 steam, steam piston 21 and air piston 32 which are con- 
 nected by piston rod 18, having made a little over half 
 their up stroke. At the bottom is shown the new style of 
 main steam valve, a piston valve instead of a slide valve. 
 
 Live steam comes from the boiler through the steam 
 pipe and governor and into steam head 19 and passes 
 into each steam chest around steam valves 5 and 6. This 
 steam passage is shown by dotted lines from 56 on each 
 side of number 19. A drain cock, 54, is tapped into this 
 passage to allow condensed water to be blown out when 
 first starting up the pump, at all other times while the 
 pump is running it should be closed. The exhaust passage 
 is shown leading from exhaust cavities of the slide valves 
 5 and 6 through 58. Under 58 comes the drain cock for 
 the exhaust; unless the pump sets high enough so all con- 
 densed water will drain to the smoke arch end, this cock 
 can be left open if so desired, providing there is a drip 
 
194 OPERATION OF DUPLEX PUMP 
 
 pipe leading to the ash pan. The steam head is made 
 with right and left side connections for live and exhaust 
 steam, the openings not used are closed with threaded 
 plugs. 
 
 When steam is shut off from the pump, there being no 
 pressure on the back of the valves 5 and .6, they drop to 
 their lowest position as shown. Live steam when first 
 turned on passes up through port 23-24 into cylinder 1, 
 and if piston 22 is not already at the bottom of its cylinder 
 1, it is forced down and held there. At the same time live 
 steam passes through port 26 under piston 21, forcing it 
 and air piston 32 upwards; air in cylinder 4 above piston 
 32 raises valve 11 and passes into upper end of high 
 pressure air cylinder 3 above piston 31. At the same time 
 while piston 32 is moving up, free air from outside raises 
 inlet valve 10, passing into lower end of low-pressure 
 cylinder 4 and filling it ready for compression on down 
 stroke of its piston. Piston 21 then remains at top of its 
 stroke till the other steam piston makes an up stroke. 
 
 When steam piston 21 approaches the top limit of its 
 stroke, tappet plate 20 catches the button on the top end of 
 the reversing or tappet rod 8, drawing this rod and slide 
 valve 6 up so that port 27 is uncovered to the live steam 
 and port 23-24-25 is connected to the exhaust. With live 
 steam passing under it and the upper side connected to the 
 exhaust, piston 22 moves upward, carrying air piston 31 
 with it and forcing the air in upper end of the high-press- 
 ure cylinder past the final discharge valve 13 into the 
 main reservoir. At the same time, air from the atmos- 
 phere flows in past valves 10 and 12, filling the lower 
 end of the high-pressure cylinder 3 with free air. The 
 low-pressure air cylinder has one inlet valve for each end, 
 9 and 10; the high-pressure air cylinder has to draw its 
 supply of free air through two inlet valves at each end, 
 9 and 11 at the top end and 10 and 12 at the bottom. 
 Valves 11 and 12 are the discharge valves for the low- 
 pressure cylinder; 13 and 14 are the final discharge valves 
 from the high-pressure cylinder to the main reservoir. 
 
OPERATION OF DUPLEX PUMP 195 
 
 As piston 22 nears the end of its up stroke, the tappet 
 plate moves rod 8 up, drawing valve 5 upwards, this con- 
 nects port 26 with the exhaust so that the steam in 
 cylinder 2 under piston 21 will pass out; port 28-29-30 is 
 opened and live steam passes in above piston 21, forcing 
 it down, bringing air piston 32 with it and compressing 
 the air in the lower end of cylinder 4 past valve 12 into 
 the lower end of high-pressure cylinder 3, and drawing 
 a supply of free air past valve 9 into the upper end of 
 cylinder 4. During this downward movement of piston 
 21, piston 22 is stationary at the top of its stroke. As 
 piston 21 nears the bottom limit of its stroke, tappet plate 
 20 strikes the shoulder on rod 8, moving it and steam 
 valve 6 to their lower position; this opens port 23-24 to 
 live steam and 27 to the exhaust; steam piston 22 then is 
 forced down, bringing air piston 31 with it; the air in the 
 lower end of cylinder 3 is forced past final discharge 
 valve 14 to the main reservoir, free air from the atmos- 
 phere passes by valves 9 and 11 and fills the upper end 
 of cylinder 3. This completes a round trip of both steam 
 and air pistons. 
 
 By means of the tappet rod each steam piston moves 
 the steam valve that opens and closes the steam and 
 exhaust ports for the other cylinder, so that when one 
 steam piston completes its stroke it has moved the steam 
 valve to operate the other steam piston and then remains 
 at the end of its stroke while the other piston makes one. 
 This ensures that the air pistons make a full stroke and 
 leave no clearance space at the ends of the air cylinders, 
 except the volume of the passages to the discharge valves 
 and leaves the air pistons in the proper position so the 
 air from the low-pressure cylinder can pass into the high- 
 pressure cylinder ready for the final compression to the 
 main reservoir. All the air valves have a lift of 1/16 
 of an inch. Oil cups 54 are in the top heads of each 
 air cylinder. 
 
 The No. 6 Duplex Pump here shown has the steam 
 end constructed in much the same manner as the No. 2 
 
NO. 6 DUPLEX AIR PUMP. 
 
 ALL AIR VALVES f^L-53 53 ~ 
 
 |/2"DIAM. J-j" LI FT L-.^T 
 
 4A +B 
 
 EXHAUST 
 
 XPf/7/*t 
 
DUPLEX PUMP 197 
 
 Duplex Pump. The air inlet and discharge valves are 
 placed in another manner, the No. 6 pump has a separate 
 air inlet for each cylinder to take in atmospheric air, their 
 location is shown in the cuts of the top end of the pump 
 and the sectional view. The bore and stroke of each 
 cylinder is shown in the cuts as well as the course of the 
 steam and air by the arrows, during the first up stroke. A 
 description of the No. 6 is not necessary here, as with the 
 description of the No. 2 pump and the illustrations, the 
 operation of the pump can be readily understood. The 
 low-pressure cylinder takes in air from the atmosphere 
 at each stroke of its piston 32 and delivers the compressed 
 air to the high-pressure cylinder through the intermediate 
 valves 11 and 12. At each stroke of the high-pressure 
 piston 31 it takes in a supply of air from the atmosphere 
 through its inlet valves 15 or 16 and afterwards receives 
 the air from the low-pressure cylinder in addition to the 
 free air taken in. The defects of this pump are treated 
 in the same manner as those of the No. 2. Leaks at the 
 inlet valves are more easily located with the No. 6 than 
 the No. 2, as there is a separate strainer for each inlet 
 with the No. 6. 
 
 DEFECTS OF THE DUPLEX PUMP 
 
 When the Duplex pump stops, first open drain cock 54, 
 if steam blows out strong the governor is all right. If 
 very little steam passes out, examine the governor. If the 
 button breaks off tappet rod 8, or tappet plate 20 gets 
 worn badly or very loose, the steam piston on that side 
 will make its up stroke, but the slide valve will not be 
 raised up to open and close the steam and exhaust ports 
 for the other cylinder. If the tappet rod is broken on the 
 high-pressure side, both air pistons will stop at the top 
 of their stroke; if the tappet rod is disabled on the low- 
 pressure side, piston 21 can move to the top of its stroke, 
 but valve 6 will not be moved up, steam will hold piston 
 
198 DUPLEX PUMP DEFECTS 
 
 22 and air piston 31 at the bottom of their strokes. 
 Taking off cap nuts 15 will soon locate which tappet rod 
 is at fault. To locate at which end of the stroke the air 
 piston has stopped, remove the oil cups from the top of 
 air cylinders and run a piece of wire down to the piston. 
 If the nuts 74 work loose and strike the top head so the 
 piston can not make a full stroke, the steam valve on that 
 side will not be moved to change the course of steam to 
 the other cylinder, and the other piston will not move. 
 This defect acts like a button broken off; it can be 
 located by taking top head 47 off. 
 
 Worn air piston packing rings will allow the pump to 
 run very fast and not make much air ; it will run hotter 
 than usual and pound badly. The air cushion necessary 
 to keep the air pistons from striking the heads will be 
 lost; this will cause the pound. Leakage of air around 
 the high-pressure piston rod will waste the air already 
 compressed, and allow the piston to strike the lower head; 
 it will also make the strokes uneven. To locate worn 
 air piston packing rings, run the pump very slowly against 
 full pressure in the main reservoir. If the rings leak con- 
 siderable, compressed air will get past the piston in the 
 latter part of its stroke; this will reduce to nothing the 
 amount of free air drawn in at the inlet valves. To 
 locate the defective piston, note which one in making its 
 stroke is not drawing in air properly. This is not a very 
 good test for the high-pressure piston, as it may be draw- 
 ing part of its supply from the low-pressure cylinder, 
 which has been expanded by the heat of the cylinder. If 
 the pump works all right at a low air pressure, and as the 
 pressure increases the low-pressure cylinder seems to be 
 doing most of the work, examine the high-pressure side 
 to see why it is not doing its share. The low-pressure 
 piston ordinarily works against a pressure of three 
 atmospheres — 30 pounds gage pressure, which is the press- 
 ure on the high-pressure piston at the beginning of its 
 stroke when both cylinders have filled full of free air from 
 the atmosphere. 
 
DUPLEX PUMP DEFECTS 199 
 
 If an inlet or receiving valve 9 or 10 leaks, the air 
 will blow out past it as piston 32 moves towards it. Both 
 valves 9-11 or 10-12 will have to leak if any air gets 
 back to the atmosphere from the high-pressure cylinder. 
 Open the ojl cup on the low-pressure cylinder, run the 
 pump slowly against the full reservoir pressure ; if valve 
 11 leaks when the high-pressure piston is moving up air 
 will pass valve 11 and blow out of the oil cup. If final 
 discharge valve 13 leaks, stop the pump, opening the oil 
 cup on the high-pressure cylinder will show it. If valve 
 14 leaks, the piston, if not at the top of cylinder 3, will 
 move up there unless the air can blow out around the 
 piston rod. Leaky air inlet valves will cause the pump 
 to make irregular strokes, quick towards the leaky valve 
 and slow away from them. If discharge valves leak, the 
 piston will move slowly towards the leaky valve and 
 quickly away from it. A leak by the gasket 48 will show 
 like a leaky air valve; to be sure which it is, the best way 
 is to take up head 47 and examine the gasket and air 
 valves. When the air valves or their seats have worn so 
 as to materially increase the lift or allow them to leak, 
 it is best to put in new valves and seats that are in perfect 
 order. When new valves are placed in the old seats or the 
 old valves ground in to a fit, be careful that the lower 
 end of the wings of the valve does not strike on the 
 cages or the stops of the valves under them. 
 
 The exhausts from the pump when run very slowly 
 against standard pressure, will usually show where the 
 air leaks are located. 
 
 Leaky steam piston packing rings will cause an inter- 
 mittent blow. Run the pump slowly against full air 
 pressure, open the drain cock in the exhaust at 58; you 
 can soon locate the defect. A leaky steam valve will 
 usually give a steady blow. 
 
 Steam escaping at the piston rod packing is liable to 
 be drawn in at the air inlet valves, and fill the equipment 
 with water; this is very dangerous in cold weather. 
 
THE PUMP GOVERNOR 
 
 The New York Air Brake Co. make three styles of 
 governors: the Single, Duplex and Triplex. As these 
 only vary in the number of air diaphram bodies attached 
 to a single steam valve body, we will describe the Duplex 
 governor, which is the one most generally used. Air 
 enters the governor at e from the brake pipe to one 
 diaphram body and from the main reservoir to the other 
 diaphram body. At f is a strainer to prevent dirt or grit 
 
 Duplex Governor. 
 
 PLATE Q 8. 
 
 yfigL t 
 
 passing from e into chamber A. Air passes into the 
 chamber A under the corrugated diaphram 13, which is 
 held down on its seat 14 by a regulating spring 10, acting 
 on the diaphram button 12. When the air pressure under 
 
OPERATION OF PUMP GOVERNOR 201 
 
 the diaphram exceeds the resistance of the spring 10, 
 the diaphram is raised off its seat on 14, this allows air 
 at the brake pipe pressure to pass down through a and 
 C into B on top of piston 4, which at once moves down, 
 also moving steam valve 5 down against its seat and shut- 
 ting off the supply of steam from the boiler to the pump. 
 A small hole at o lets a little steam pass through to the 
 pump so it will make a stroke at intervals. A vent port 
 V in the cylinder 1 over piston 4 allows air to blow out 
 steadily while the air pressure is operating the governor, 
 this also tends to keep the pump moving. When the air 
 pressure drops so that spring 10 can hold diaphram 13 
 on its seat, the air escapes from chamber B over piston 
 
 4 through vent V ; valve 5 and piston 4 are raised by the 
 steam pressure and the steam again passes to the pump. 
 When valve 5 is at the top of its travel a steam tight 
 seat is at S, so no steam can work up under the piston 4. 
 The dotted lines at x show the location of the drip open- 
 ing in the side of the cylinder 1, which allows any steam 
 that works up past valve 5 or air that comes down by 
 packing ring 24 to escape to the atmosphere. When valve 
 
 5 is partly open, steam can blow out at the drip steadily 
 as its stem does not make a steam tight fit in the guide 6. 
 The regulating springs over the air diaphrams are adjusted 
 by the small adjusting screw 8 and fastened by the jam 
 nut 9. 
 
 The later pattern of governors have a large adjusting 
 nut, it is shown in the Duplex Controller. 
 
 The single governor is usually set at 70 pounds, as it 
 controls the brake pipe pressure and is piped to passage 
 E in the brake valve on the brake pipe side of the excess 
 pressure valve 97. 
 
 The Duplex governor has the low-pressure air dia- 
 phram chamber connected to the brake pipe or chamber A 
 of the brake valve, the opening into E of the brake valve 
 must be plugged, and main reservoir air to the high- 
 pressure side. The brake pipe side is set at 70 pounds 
 and the main reservoir side at 90. With this arrangement, 
 
202 PIPING THE GOVERNOR 
 
 if the governor diaphrams are not set for the proper 
 pressures, the brake pipe pressures in running and full 
 release positions will not be right. 
 
 With the Double Pressure system, where a low brake 
 pipe pressure is carried with empty cars and a higher one 
 with loaded cars, both sides of the duplex governor are 
 piped to the opening E. In the pipe leading to the low- 
 pressure side of the governor there is a cut-out cock, 
 when this is shut the higher brake pipe pressure will be 
 carried. 
 
 With the Triplex governor one air diaphram is con- 
 nected to the brake pipe and set at one standard pressure, 
 the second diaphram is set for a higher brake pipe press- 
 ure, and the third diaphram is connected to the main 
 reservoir air and set at the pressure desired there. There 
 is a cut-out cock in the air pipe leading to the lowest 
 brake pipe diaphram, which can be closed when necessary 
 to carry a higher brake pipe pressure; this cuts the lowest 
 one out of service. The diaphram 13 gets gummed up on 
 the seat of 14 so that in some cases air leaks by it and the 
 governor piston is operated before the proper pressure is 
 reached. Or it may .get gummed up so much that air 
 can not pass down to the piston. For defects common 
 to governors, see front of book. 
 
 THE 1902 MODEL BRAKE VALVE 
 
 The duty of the brake valve is to control the passage of 
 air from the main reservoir to the brake pipe ; from the 
 brake pipe to the atmosphere or stop the flow of air 
 through it in any direction. The engineer's brake valve, 
 when in full release position, should allow the main 
 reservoir air to flow directly to the brake pipe through 
 large ports to equalize these pressures quickly. It should 
 allow the air to pass through smaller openings in running 
 position and maintain a higher pressure in the main 
 reservoir after the brake pipe pressure has reached a 
 standard amount. It should have a moderate opening 
 
Engineer's Brake VaJve. 
 1902 MODEL, ^ 
 
 „ TO ( ti"~'0% 
 
 GOVERNOR jV %=M j \ 
 
 FACE OF SLIDE VALVE 
 
 K- -> 
 
 CF 
 
 Rf-M 
 
 Supplementary Re&ervoir 
 
 rfTT^-- Z LD 
 
 0\P 
 
 © \ (o \ 
 
 o 
 
 E? 
 
 ra^s- 
 
 4 
 
 tf 
 
 / O MO Q 
 
 E B 
 
 O 
 
 SLIDE VALVE SEAT 
 (l23\ 
 
204 1902 MODEL BRAKE VALVE 
 
 for the brake pipe air to pass to the atmosphere in a 
 graduated service application, and should automatically 
 close the opening when the brake pipe pressure has been 
 reduced the desired amount to operate the triples with 
 a graduated application. It should also have a large and 
 direct opening to the atmosphere to exhaust the brake 
 pipe air quickly in an emergency, so the triples will oper- 
 ate quick-action. 
 
 The New York Brake Valve is shown in a sectional 
 view. The brake valve body, 101-A, contains a main slide 
 valve, 114-A, which is moved back and forth over the 
 slide valve seat by the slide lever 118 and links 116; this 
 lever is attached to lever shaft 120, and moved by handle 
 123. Plugs 96 can be taken out to oil the slide valve 114. 
 Main reservoir air enters the body of the valve, passing 
 up into chamber B, and is all around the sides and on top 
 of slide valve 114-A. It also passes to the red hand of 
 the gage and to the high pressure side of the duplex 
 governor. The black hand gets air from the brake pipe 
 side of the brake valve. When this valve is in full re- 
 lease position, main reservoir air passes directly through 
 the port a into chamber A, which is connected with the 
 brake pipe directly, so that in this position main reservoir 
 air can equalize with the brake pipe; if the duplex gage 
 is right both hands will show the same pressure. When 
 the handle 123 is moved back to 'running position, port a 
 is covered by the end of the slide valve so no air can pass 
 through a; main reservoir air must then pass from B 
 under excess pressure valve 97, raise it against the stiffness 
 of its spring 90, pass through E into the cavities M-M 
 in the face of the slide valve and through a into A. Brake 
 pipe pressure is also holding valve 97 down in addition 
 to the stiffness of spring 90, so that with' main reservoir 
 pressure on one side and brake pipe pressure on • the 
 other side of 97, spring 90 is able to maintain a steady 
 difference in these pressures, at whatever amount the 
 main reservoir pressure may be. This difference is usually 
 20 pounds. 
 
1902 MODEL BRAKE VALVE 
 
 205 
 
 Two sectional views are shown giving the position of 
 the excess pressure valve 97, the ports from B to E, 
 and showing the main reservoir, brake pipe and gage 
 connections. The connection to the supplementary reser- 
 voir and port H is shown on the side elevation.- 
 
 In the lower part of the valve body, 101-A, is a piston, 
 104- A, moving in a bushing; this piston by means of the 
 
 GAGE 
 
 RED HAND 
 
 MAIN 
 RESERVOIR 
 PRESSURE 
 JO 
 MAIN 
 RESERVOIR 
 
 graduating valve lever 112, can move the graduating or 
 cut-off valve 110, which rests against the lower face of 
 slide valve 114-A, and in its normal position covers the 
 port F that is connected by a passage through the middle 
 of the slide valve with port G, which in service position is 
 open to the atmosphere through cavity C. When the slide 
 valve is moved to the first notch in service application 
 position, brake pipe air can flow from A through a, ports 
 F and G into C, and reduce the brake pipe pressure. 
 Chamber D on the other side of the piston 104-A is con- 
 nected with the supplementary reservoir 155, which has a 
 pressure in it at the beginning of the brake pipe reduction 
 
206 OPERATION OF BRAKE VALVE 
 
 equal to that in the brake pipe. As the brake pipe press- 
 ure is reduced, the air in chamber D and 155 expands, 
 and moves piston 104-A towards the reducing brake pipe 
 pressure in A, this in turn moves cut-off valve 110 back 
 and closes port F, thus cutting off the flow of brake pipe 
 air to the atmosphere, without any movement of the 
 handle 123 to lap position; this is expected to reduce the 
 brake pipe pressure about 4 pounds. A further movement 
 of handle 123 to the next service notch will move valve 
 114- A so that port F will be again opened; when the 
 proper reduction has been made, cut-off valve will again 
 close port F. Successive reductions can be made by 
 moving handle 123 to the next service notch till the last 
 one is reached, when the brake pipe pressure will have 
 been reduced about 23 pounds, and the brakes applied 
 in full service. The size of the supplementary reservoir is 
 such that when the air in it expands into the additional 
 space made when piston 104-A moves clear forward, the 
 pressure will be reduced from 70 to about 47 pounds, or a 
 little over two-sevenths of the original pressure; with a 
 higher pressure the total reduction will be greater. 
 
 To reduce the brake pipe pressure suddenly and 
 directly, 123 is moved at once to the emergency position; 
 this opens the large ports J-J to A so that brake pipe air 
 passes through two passages ; one on each side of F-G 
 and out at K to C. This sudden discharge of brake pipe 
 air through the large openings will reduce the pressure 
 quickly and operate the triples quick-action. After any 
 application, whether service or emergency, the brake valve 
 should be placed in full release position till the brake pipe 
 has been charged its full length, and all triples moved to 
 release position, if it is desired to release all brakes 
 properly. 
 
 If piston 104-A has been moved forward by the press- 
 ure in chamber D at the time of a reduction of brake pipe 
 pressure, it must be moved back to its normal position 
 when the brakes are released if it is to be ready to move 
 cut-off valve 110 to graduate the next brake pipe reduc- 
 
OPERATION OF BRAKE VALVE 207 
 
 tion. To do this some of the air in chamber D and reser- 
 voir 155 must be discharged to the atmosphere. This is 
 done through port and passage O, which passes through 
 the valve cover 115-A as shown in illustrations, back 
 into the valve body 101-A and out to C through port J 
 when the valve is in full release, or through cavity P in 
 the slide valve when in running or lap position. Another 
 passage, H, connects chamber D at all times with reservoir 
 155, so that when air can pass out of chamber D through 
 O, it can also pass out of reservoir 155. With air exhaust- 
 ing from chamber D and brake pipe pressure in A, piston 
 104-A is at once moved back to its normal position; also 
 moving cut-off valve 110. In the end of piston 104-A 
 is a valve, 180, that closes port O when the piston is in 
 the normal position and the brake valve in full release, 
 running position or lap, and prevents any air from chamber 
 D flowing out at port O. Air from the brake pipe can 
 flow from A up past ball valve 184, and recharge chamber 
 D at all times when the pressure is less in D than in A; 
 but cannot flow back into A as the valve 184 prevents this. 
 This recharges chamber D and reservoir 155 as soon as 
 piston 104-A moves to normal position and seats valve 
 180, closing passage O. The opening past ball valve 184 
 and through the piston into chamber D, is much smaller 
 than O, so chamber D air can be exhausted through O 
 faster than it can feed in at 184, this ensures the move- 
 ment of piston to its normal position. The older pattern 
 of Vaughn-McKee valve does not have this recharging 
 attachment, and in all cases in releasing brakes the valve 
 must be replaced in full release an instant to discharge 
 the air from chamber D, then moved to running position 
 to recharge chamber D, in order to get the graduating 
 action of piston 104. 
 
 As the supplementary reservoir is supplied with air 
 from the brake pipe, while this reservoir is charging after 
 an application and release of the brake on a lone engine 
 with the older type of the Vaughn-McKee valve, the brake 
 pipe pressure will be reduced at the instant of placing the 
 
208 BRAKE VALVE DEFECTS 
 
 valve on running position. This reduction of pressure may 
 apply the engine brake; as soon as air begins to pass the 
 excess valve the brake should release. 
 
 If the supplementary reservoir pipe is broken or leak- 
 ing so a blind joint must be made at the valve, there will 
 be so little air in chamber D that the equalizing piston 
 will not move valve 110 to graduate and stop the flow of 
 air from brake pipe, and handle 123 must be moved to 
 lap position to stop the discharge of brake pipe air. 
 
 As this valve has two sets of exhaust ports, one small 
 for the service application and a large port for the emer- 
 gency application, the work of reducing the brake pipe 
 pressure is very easily regulated. 
 
 DEFECTS OF THE BRAKE VALVE 
 
 If air leaks past main slide valve into brake pipe, it 
 will not maintain excess pressure, if the valve is in 
 service or lap position during an application of the brake 
 this leak will recharge the brake pipe and release the 
 brake. To test for this leak, place the valve on lap, close 
 the cut-off cock and start the pump; any leak into the 
 brake pipe will be shown on the black hand. If the leak 
 is only shown when the valve is in running position, the 
 excess pressure valve is at fault; it usually only needs 
 cleaning. While doing this do not scratch either the valve 
 or its seat, or it will surely leak after cleaning. If the 
 cut-off valve 110 leaks, it will not stop the flow of air 
 from the brake pipe in a service application; you can hear 
 the continuous blow at the exhaust opening. This blow 
 will stop if you move the valve back to lap. If the cut- 
 out cock is closed, the black hand will drop to zero, unless 
 there is a leak into the brake pipe cavity A. A leak 
 through the leather gasket under the cap 115-A that 
 allows main reservoir air to get into port O, will cause 
 a blow at the exhaust in any position between lap and full 
 release. In any other position it will charge chamber D 
 
BRAKE VALVE DEFECTS 209 
 
 direct from the main reservoir. The openings in the 
 gasket at O should be the exact size of the port O. 
 
 A leak from the supplementary reservoir or its con- 
 nections, if to the atmosphere, is easily detected, and 
 should be remedied if the automatic closing of the cut- 
 off valve 110 is to be satisfactory. This leak will reduce 
 the pressure in the reservoir so the piston 104 will not 
 move. A leak from chamber D back into the brake pipe 
 can be detected by closing the cut-out cock under the 
 brake valve, placing the valve in emergency for an instant 
 to empty chamber A and then in the second service notch; 
 a leak into chamber A will be shown on the black hand. 
 This leak may be past the leather packing ring or by the 
 ball valve. Before making this test be sure main slide 
 valve does not leak from main reservoir into brake pipe. 
 Lost motion between handle 123 and main slide valve will 
 allow the slide valve to leave the ports only partially 
 open; this will affect the release of the brake very 
 seriously. This affects a brake pipe reduction when made 
 in the first graduating notch. 
 
 THE STRAIGHT AIR BRAKE 
 
 The Straight Air Brake valve shown in Figs. 1 and 
 2, has a slide valve 227, which is moved by the lever 222 
 with its lever shaft 224, and slide valve lever 232. When 
 in release position, Fig. 2, the port b, leading from the 
 brake cylinder pipe is connected with the exhaust e by the 
 cavity c of the slide valve. To apply the brake the handle 
 222 is moved to application position. This moves valve 
 227 so as to lap or cover the exhaust port e and uncover 
 port b. Main reservoir air, which has been reduced to 45 
 pounds at the reducing valve, Fig. 3, can then flow from 
 A into b and thence to the double check valves and brake 
 cylinders. Gasket 121 prevents leakage of air along the 
 shaft 224. The reducing valve shown in Fig. 3 is located 
 between the main reservoir and the brake valve. The 
 diaphram complete consists of the stem 21, the washer 
 
210 
 
 THE STRAIGHT AIR BRAKE 
 
 23 and the rubber diaphram 32. It is held down against 
 the air pressure in B by the regulating spring and its stem 
 19. As long as the pressure in B is less than the regulat- 
 
 r~\ 
 
 THE NEW YORK AIR BRAKE CO 
 
 Straight Air Engineer's Valve, , 
 
 i /// 
 
 TO MAIN RESERVOIR 
 9/SPlPE. 
 
 ing spring is adjusted for, which is 45 pounds, the feed 
 valve 26 is held off its seat. When this pressure reaches 
 45 pounds, the spring should allow the diaphram to raise 
 and allow feed valve 26 to seat, thus shutting off the 
 flow of air from A into B. 
 
 The safety valve, Fig. 6, has a release lever to raise 
 the valve off its seat to lower the brake cylinder pressure 
 
B-2 BRAKE VALVE 
 
 211 
 
 when necessary. This safety valve for the driver brakes 
 can be located in the cab, if desired, and is to set at 52 
 pounds, as is the tender brake safety valve. 
 
 Safety Valve Fig. 6, 
 
 With Release Lever. 
 
 Fig. 3 
 Reducing Valve, 
 
 The double check valve used is shown in Fig. 4, 
 question 38. The same rules apply to the operation of this 
 straight air brake as to the Westinghouse equipments. 
 
 The B2 Brake Valve is designed to operate the auto- 
 matic brake on train and engine in the same manner the 
 1902 model valve does, and in addition apply the driver 
 brake with straight air, this does away with a separate 
 straight air brake valve. It also operates an accelerator 
 valve that passes air out of the brake pipe to the atmos- 
 phere during a service application on a long train and 
 thus makes the operation of the triple valves more pos- 
 itive and quicker. There is a duplex controller that regu- 
 lates the supply of main reservoir air to the brake valve 
 
B-2 BRAKE VALVE 
 
 213 
 
 by reducing it to brake pipe pressure before it reaches 
 the brake valve, so the pressure in the main reservoir 
 side of the valve will not rise above the standard desired 
 in the brake pipe, this does away with the excess pressure 
 attachment used with the 1902 model. The arrangement 
 of this equipment is shown in piping diagram on this 
 page. 
 
 There is no ball check valve 184 in the piston, chamber 
 D being charged from the air in B around the slide valve 
 
 EVI9CT 
 EV192 
 
 QT29- 
 QT3iz 
 QJ30- 
 
 B-2 Brake Valval 
 
 JACCE^KATOO 
 
 VM.VE «t$t*VO<* 
 
 y./--°^ 
 
 FACE OF SLIDE VALVE 
 
 4 • fira §9 I • 
 
 -I _^4.)g r.^ik 
 
 W ***** CVUNOCR» 
 
 through a small port W in the valve seat leading into 
 passage H and the supplementary reservoir. Passage O 
 and vent valve 180 in this valve serve the same purpose as 
 
214 OPERATION OF.B-2 BRAKE VALVE 
 
 in the 1902 model, to discharge air from chamber D so 
 that brake pipe pressure can return piston 193 to its normal 
 position, when valve 180 closes port O. 
 
 A sectional view of the B2 valve is shown, also a plan 
 of the face of the slide valve and its seat. The chief 
 differences between this valve and the 1902 model are the 
 ports in the slide valve and the seat. Two ports, E and 
 V, in the seat are connected by a cored passage shown by- 
 dotted lines through the valve body and located above 
 passage H, into this passage the pipe leading to the brake 
 cylinders is attached. When the slide valve is clear ahead 
 in full release it uncovers port E so air from the top of 
 the valve in B can pass through the reducing valve set at 
 40 pounds, to the brake cylinders, this applies the engine 
 brake straight air. Air from B passes by the end of the 
 slide valve and also through ports M in the slide valve 
 into the brake pipe as fast as the air can pass the con- 
 troller, releases the train brake and charges the brake 
 pipe and auxiliaries. Port T in the seat, leading to the 
 accelerator reservoir is open through J in the slide valve 
 and exhaust C to the atmosphere and port O is the same 
 as explained with the 1902 model. Port W is open and 
 keeps chamber D equalized with B. In this position the 
 train brake is released and the driver brake set straight 
 air. 
 
 In running position the slide valve is moved back 
 covering port E so no more air passes to the brake cylin- 
 der pipe, port V in the seat registers with R in the valve 
 so brake cylinder air can exhaust through R, J and C, 
 this releases the driver brake. Air can pass to the brake 
 pipe through the large ports M in the slide valve so run- 
 ning position releases both the train and driver brakes. 
 Ports O and T are still open to J and the atmosphere. 
 On lap all ports are blanked except port O, this is left 
 open to return the piston and graduating valve to normal 
 position, if a service reduction has been made so the 
 valve will graduate at the next reduction. 
 
 In the graduating positions, ports F and G are opened 
 
OPERATION OF B-2 BRAKE VALVE 215 
 
 by a movement of the slide valve and port F closed by 
 the graduating valve as with the 1902 model. But as port 
 S in the valve is opened at the same time with port F, 
 when air is flowing from F into G, it is also flowing 
 through S, the passage X and into the opening Ac that is 
 connected by port T in the seat and Y to the accelerator 
 reservoir. As soon as the proper brake pipe reduction 
 for that notch is made valve 110 will close ports S and F. 
 A movement of the handle to the next notch will open 
 ports S and F again and valve 110 will close them; 
 brake pipe air flows to the accelerator valve chamber at 
 the same time it flows through F and G and exhaust C. 
 When the last graduating position is reached the restricted 
 passage N in the end of the slide valve has been moved 
 over port V so air begins to flow from the brake valve to 
 the brake cylinder. As the engine triple valve has been 
 sending air to the cylinders during the service application 
 the supply of air through port V tends to maintain the 
 pressure during a full application. The action of the 
 valve in emergency is exactly like that of the 1902 valve 
 before described. The reducing valve used with this 
 equipment is the same one described in connection with 
 the Straight Air Brake. 
 
 B 3 BRAKE VALVE 
 
 This valve in some respects is similar to the B2 just 
 described. The engine and tender brake have triple 
 valves for automatic service and double check valves to 
 enable straight air to be used, which can be applied in 
 full release or emergency positions releasing it in run- 
 ning position whether applied with straight air or auto- 
 matically, with this valve the main reservoir pressure is 
 reduced to 40 pounds before reaching the brake valve for 
 use in straight air applications. It operates the acceler- 
 ator valve in the same manner as the B2, using the same 
 design of divided reservoir. 
 
 The piping diagram of the B3 when compared with 
 
OPERATION OF B-3 BRAKE VALVE 
 
 217 
 
 the B2 will show some of the differences. A sectional 
 view of the complete valve, also a plan of the slide valve 
 and its seat is shown so the differences between the ports 
 and cavities in the B2 and B3 are plain. The valve cover 
 is fastened to the body by tap bolts instead of screws; 
 port o is cored through the body instead of being drilled 
 through the cover, it does not show in the sectional side 
 elevation. The plan of the valve seat and body shows a 
 pipe bracket bolted to the side, dotted lines show the 
 cored passages to port N and from port E through which 
 air passes on its way to the brake cylinders in a straight 
 
 til W B^ Brake Valve. 
 
 , i" COPPER P« 
 TO ACCCLERATOf? 
 «C&ERVC'» 
 
 SUPPLEMENTARY 
 
 air 
 the 
 
 «tS£Rvoia — x^_^' V y cuwor» 
 
 application. V is the straight air exhaust port; C is 
 brake pipe exhaust port; o is the discharge port 
 
218 OPERATION OF B-3 BRAKE VALVE 
 
 through which the air from behind piston 311 can pass 
 out in full release, running and lap positions ; T is the 
 port leading to the accelerator reservoir ; W leads to the 
 supplementary reservoir and chamber D behind piston 
 311; A is the opening through which main reservoir air 
 that enters at B can pass into the brake pipe in release 
 and running positions. On the plan of the face of the 
 slide valve, M-M are two openings in the end of the 
 valve through which this air passes in release and run- 
 ning positions as well as passing by the end of the valve 
 in full release; port F is connected to G by a passage 
 through the body of the valve 312, better shown in the 
 side elevation and used in service application to pass air 
 from A to C; ports J-J are likewise connected with K 
 and large enough to make the emergency reduction from 
 A to C; groove P in the face of the valve serves to charge 
 chamber D and supplementary reservoir through port W 
 in release and running positions; ports L-L are connected 
 by a cavity in valve 312, they register with ports N and 
 E for the straight air application in full release; cavity 
 R connects E and V in running position to release the 
 straight air brake, and to discharge air from port o in 
 release, running and lap position. Port S connects with 
 cavity through Ac, a passage shown by dotted lines ; cavity 
 Ac is oyer port T leading to the accelerator reservoir in 
 the graduating positions so that some of the brake pipe 
 air escaping during a service reduction can flow to the 
 accelerator reservoir and build up a pressure there to 
 operate the accelerator valve; port T is open to J in 
 running position so air can all escape from the acceler- 
 ator reservoir. 
 
 Main reservoir air reduced to the standard brake pipe 
 pressure at the duplex controller comes into the brake 
 valve at B and is around the slide valve, in automatic-re- 
 lease and straight-air-application position air flows through 
 ports M and by the end of valve 312 into the brake pipe 
 and equalize there with B. Main reservoir air also passes 
 the single pressure controller set at 40 pounds into port 
 
OPERATION OF B-3 BRAKE VALVE 219 
 
 N then through port E, the double check and into brake 
 cylinder. Port o is open to cavity R and port V so air 
 behind piston 311 is discharged to allow brake pipe air to 
 force the piston to normal position, when in normal 
 position valve 180 closes port o at that end and no more 
 air can pass through o } the supplementary reservoir will 
 then charge through port W; port T is open through J 
 and C. Placing the brake valves midway between release 
 and running position will lap the straight air ports N and 
 E so no air can pass in or out of the brake cylinders 
 through the brake valve and will hold the engine brakes 
 partially applied. 
 
 Running position will release both automatic and 
 straight air brakes, the straight air will come back through 
 port E and passing into cavity R will escape through V 
 into C. In lap position all ports are closed, except o, 
 this open port is to return piston 311 to normal position 
 in case it has been moved in a service application and 
 the brake valve moved to lap. There are five service or 
 graduating positions, each having a notch in the quadrant, 
 they are calculated to make automatic reductions from 70 
 pounds brake pipe pressure of 5, 8, 11, 15 and 23 pounds, 
 or in that proportion for any higher pressure. In any 
 service reduction, ports F and S in the face of valve 312 
 are open, F to the atmosphere through G ; S to Ac and 
 the accelerator reservoir till the brake pipe reduction is 
 sufficient to allow air in chamber D to move piston 311 
 and cut-off valve 317 to close them. In the last graduating 
 notch cavity R opens to port N a very little so main 
 reservoir air can flow from N to E, into the double check 
 and cylinders and reinforce the automatic application if 
 it has leaked below 40 pounds. 
 
 In the emergency position ports J and K allow the 
 brake pipe air to flash out to the atmosphere, this sudden 
 reduction of brake pipe pressure operates all triples as 
 quickly as possible. The straight air is also set full on 
 through ports N and E in case the triple valves does not 
 make the cylinder pressure on the engine above 40 pounds. 
 
220 
 
 DUPLEX CONTROLLER 
 
 The reducing valve for the straight air brake is a 
 54-inch single controller, the regulating top is connected 
 with a small pipe with the pipe leading from the B3 
 valve to the double check, so the controller operates to 
 close off when the pressure builds up in this pipe to 40 
 pounds. With no air in this pipe the controller is open 
 and main reservoir air comes as far as port N without 
 any reduction. In all other respects the equipment of 
 divided reservoir, accelerator valve, safety valve and high 
 speed controller is the same as with B2. 
 
 DUPLEX CONTROLLER. 
 
THE DUPLEX CONTROLLER 
 
 This valve is located between the main reservoir and 
 the brake valve ; its duty is to reduce the main reservoir 
 pressure to that required in the brake pipe before reach- 
 ing the brake valve. There are two forms of it in service, 
 only the latest form of it is here illustrated. In its con- 
 struction it is like the duplex pump governor, except that 
 its valve has a leather seat. The regulating tops can 
 be located in the cab and connected to the controller body 
 by a copper pipe. One of the tops is adjusted for the 
 ordinary brake pipe pressure, the other for the higher 
 pressure used with the High Speed Brake. When one 
 side is cut in by the union three-way cock the other is 
 cut out, either one of the tw T o pressures can be carried in 
 the brake valve and brake pipe. The description of the 
 duplex pump governor and its operation will be sufficient 
 to show how the controller operates. Air enters at the 
 opening marked MR, if the controller valve is open it 
 can pass through and out to the brake valve at BV. 
 When necessary in steep grade work to have full main 
 reservoir pressure in the brake valve the controller valve 
 can be held open by screwing. the hand wheel up the full 
 travel of its screw. 
 
 THE ACCELERATOR VALVE 
 
 This valve is intended to discharge brake pipe air 
 during a service reduction in addition to that taken out 
 by the brake valve. It has a divided reservoir; one side 
 for the accelerator valve to which the valve is bolted, the 
 other is the supplementary reservoir for the brake valve. 
 When air from the brake valve during a service reduction 
 passes through ports S and T to the reservoir it also 
 comes through port Q over piston 65. With a short train, 
 less than ten cars, port S is closed by the graduating 
 valve before sufficient air has passed into the accelerator 
 chamber to operate its valve. With a train of over ten 
 
222 
 
 OPERATION OF ACCELERATOR VALVE 
 
 cars the pressure in* the chamber will build up till it is 
 sufficient to force piston 65 and with it stem 67 and valve 
 74 down against the tension of spring 31 in the bottom 
 of the valve. In valve 74 is an oblong port a and in the 
 seat a A shaped port b. When valve 74 is moved down 
 port a first opens to the pointed end of port b, and brake 
 pipe air coming in at the opening TP begins to flow out of 
 b slowly. As the valve 74 is moved farther down by the 
 increasing pressure of the air above piston 65, ports a and 
 b are opened wider till their full opening is made; this 
 gives a gradual discharge of brake pipe air that with a 
 long train begins about four seconds after the brake valve 
 begins discharging air. It requires 15 to 17 pounds press- 
 ure in the chamber to operate the valve. Through piston 
 65 is a small port S through which air that comes over 
 the piston can discharge into the space under the piston 
 and then to the atmosphere through port T ; air flows out 
 here at the same time it comes into the reservoir and 
 prevents any sudden rise of pressure in the reservoir. 
 
 When piston 65 moves down it uncovers port R in the 
 bushing, this also takes air out of the reservoir. As soon 
 as the graduating valve laps port S in the brake valve, 
 
THE HIGH SPEED CONTROLLER 
 
 223 
 
 no more brake pipe air will flow to the chamber; ports 
 S and R in the accelerator piston will then gradually re- 
 duce the pressure in the chamber and allow spring 31 to 
 move valve 74 and piston 65 up, gradually closing ports 
 a and b. When piston 65 closes port R the flow of air 
 out of S alone is so much slower that piston 65 gives a 
 very slow closure to port b. The gasket 70 makes a tight 
 joint on its seat around stem 67 when the valve is closed, 
 so brake pipe air cannot escape around the stem. 
 
 THE HIGH SPEED CONTROLLER 
 
 The high speed controller connects with the brake 
 cylinder pipe at BC and to the brake pipe at BP, so that 
 brake pipe air pressure is always in the body of the valve 
 and when greater than brake cylinder pressure will hold 
 
 \HSr05 
 \HSIIO 
 To Brake Cylinder* H S 109 
 
 *-Pipe 
 
 piston 107 in normal position as shown, leather gaskets 
 are on each side of the piston to make the joint tight. A 
 moderately large opening around the valve 108 allows air 
 from the cylinder to reach the safety valve freely and 
 
224 THE AUTOMATIC CONTROL 
 
 rapidly reduce any excess of pressure above that the 
 safety valve is set for, this takes place in a service applica- 
 tion. In an emergency application the brake pipe pressure 
 is suddenly reduced below what the brake cylinder can 
 build up to, and piston 107 will move over to the right 
 with the leather gasket resting against the seat C. This 
 brings the small valve 108 under passage G so the cylinder 
 air blows down gradually in this position till the limit 
 for which the safety valve is adjusted is reached, this 
 should be 53 pounds. Ports D and F are to allow cylinder 
 air quick access to the *ends of the valve 108 and piston 
 107 so they will move with a low difference of pressures 
 on piston 107. 
 
 The Automatic Control equipment of the New York 
 Brake Co. is for locomotive service, either with or with- 
 out the train brakes. The piping diagram shows the 
 various parts, the automatic brake valve; double pressure 
 feed valve ; reducing valve ; pump governor ; strainer 
 check valve and safety valve are the same in construction 
 and operation as those described in answer to questions 
 35-37, so they need not be described again here. The 
 straight air brake valve and double throw check valve 
 have been described in the New York equipment a few 
 pages previous. The straight air brake valve is used to 
 pass air directly to and from the locomotive brake cylin- 
 ders, it does not send any air to the Automatic Control 
 valve as the independent brake valve does to the distrib- 
 uting valve in the ET equipment. The double throw 
 check valve is located in the pipe line between the brake 
 cylinders and the straight air brake valve on one side and 
 the Automatic Control valve on the other side; the duty 
 of this double throw check is to close the exhaust to the 
 straight air valve when the control valve is operated and 
 vice versa. A safety valve is attached to the control 
 valve and a release valve or bleeder to the retaining 
 pipe between the control valve and the automatic brake 
 valve. Stop cocks are located in the various pipes to cut 
 out the air when necessary and choke fittings near the 
 
226 
 
 AUTOMATIC CONTROL VALVE 
 
 hose connections leading to the tender brake and engine 
 truck brake to hold the air back in case either of these 
 hose burst or come uncoupled. The double chambered 
 reservoir is the same as shown with the ET equipment. 
 
 Automatic Control Valve 
 
 fDP52C^ 
 
 PTI56 
 CVI07- 
 
 The Automatic Control valve is shown in two sectional 
 views, the view at the right shows the passages to the 
 double chambered reservoir, the left one a sectional view 
 from in front. On another page is shown a diagrammatic 
 view, as the air ports and valves cannot be shown in a 
 correct sectional view. This cut shows the double 
 chambered reservoir attached at the bottom of the valve, 
 the reservoirs are of such a relative size that they will 
 equalize at 50 from 70 pounds in the auxiliary. 
 
 The valve is in full release position, triple valve piston 
 3 is at the bottom of its cylinder so feed port at G is 
 open, slide valve 4 and graduating valve 10 are in normal 
 position to exhaust air from the control reservoir and 
 chamber D above control piston 2. Control piston 2 is 
 at the upper end of its cylinder in normal or release 
 position, by it exhaust valve 7 is held open so brake 
 cylinder air coming in at C can escape at exhaust N. 
 Main reservoir air comes in at A at full pressure around 
 admission valve 1, spring 8 holds this valve on its seat 
 when there is no air pressure to do it. Brake pipe air 
 
FULL RELEASE 
 
 TO LEVER RELEASE 
 
 o 2 
 
 TO BRAKE VALVE 
 
 Automatic Control Valve. 
 
228 OPERATION OF AUTOMATIC CONTROL VALVE 
 
 comes in over piston 3 at BP; at IV is the exhaust 
 through the control cylinder release pipe connected to the 
 automatic brake valve; the control reservoir pipe is at II 
 and the continuous feed pipe from the reducing valve 
 pipe of the straight air valve to the auxiliary reservoir 
 is at VI. The safety valve is attached to port L and will 
 blow down the pressure in the control reservoir to 
 standard with either a full service or emergency applica- 
 tion ; with the triple valve on lap the safety valve is cut 
 out. 
 
 To operate this valve after the auxiliary reservoir is 
 charged to standard pressure from the brake pipe, a brake 
 pipe reduction is made. Piston 3 at once moves up follow- 
 ing the reduction in F carrying with it graduating valve 
 10 and slide valve 4; closing feed groove G; moving valve 
 10 to uncover port J in slide valve 4, which is moved 
 up so port J registers with E in the seat, also lapping 
 exhaust port M. Air from the auxiliary reservoir now 
 flows into the control reservoir and D over control piston 
 2 building up a pressure in both places. When the press- 
 ure in the auxiliary is a little less than that of the brake 
 pipe, piston 3 will move down carrying valve 10 with it 
 and lap port J so no more air can go into D and the 
 control reservoir. Pressure on piston 2 will move it 
 down carrying valve 7 down over exhaust port N, a 
 farther movement will push preliminary admission valve 
 Al off its seat in admission valve 1, this allows air in O 
 to flow out into B ; as air cannot get by the guide case 
 or extension of 1 as fast as it gets out, this tends to 
 balance valve 1 so piston 2 can open it easily. Main 
 reservoir air then flows into B and the brake cylinders 
 till the pressures there are a little above that in D and 
 the control reservoir, piston 2 then moves up and allows 
 valves 1 and Al to close, but does not open exhaust 
 valve 7, this holds the engine brakes applied automatically. 
 If, on account of leaks, the brake cylinder pressure drops, 
 it will be less than in D, piston 2 will at once open the 
 admission valve and raise the cylinder pressure and in 
 
OPERATION OF AUTOMATIC CONTROL VALVE 229 
 
 B till it can push piston 2 up so admission valve can 
 just supply the leak. For a full application the brake 
 pipe pressure is reduced 20 pounds from 70, this will 
 hold triple piston up and slide valve ports open, equalizing 
 the auxiliary and control reservoirs. 
 
 If, on a full application the pressure in the control 
 reservoir exceeds the adjustment of the safety valve, it 
 will blow down, the brake cylinder pressure will not build 
 up any higher than that in D. Air from the control 
 reservoir can flow to the safety valve from port E 
 through U, cavity V in valve 10 and port W into L. 
 
 When an emergency application is made, piston 3 and 
 its valves make a full travel at once, valve 4 uncovers port 
 E so auxiliary air can flow quickly into D forcing control 
 piston 2 down, operating its valves in short order. Port 
 P in the slide valve now registers with port L so air 
 from the auxiliary and control reservoirs can get to the 
 safety valve. A small port in the automatic brake valve 
 (if the rotary is in emergency position), will send a 
 supply of main reservoir air through the pipe marked CR 
 on the piping diagram into the control reservoir at II, 
 this will hold the pressure there up to where port P can 
 handle it all to the safety valve, thus giving a higher 
 braking pressure in the emergency than in a service ap- 
 plication. 
 
 A quick-action cylinder cap for the triple valve can 
 be furnished if desired that will vent some of the brake 
 pipe air to chamber B below control piston, this will 
 operate the car triples quicker than when the reduction 
 is made at the brake valve only. 
 
 To automatically maintain the pressure in the auxiliary 
 reservoir there is a pipe connected at VI that leads from 
 the reduced pressure pipe between the reducing valve and 
 the straight air brake valve, on the diagram this is 
 marked PC. If from any cause the pressure in the 
 auxiliary drops below the adjustment of the reducing 
 valve (which should be set at 45 pounds), air can flow 
 into the auxiliary and set the brake through the control 
 
230 
 
 STRAINER CHECK VALVE 
 
 valve up to that pressure. To do this it moves the triple 
 piston up against the depleted brake pipe pressure and 
 passes into D, thus operating piston 2. There is a 
 strainer check valve in pipe PC to prevent air at over 
 45 pounds getting back into the reduced pressure pipe 
 and a stop cock to cut out the air in case the reducing 
 valve gets out of order or the brake pipe is cut out. If 
 at any time the pressure in the reduced pressure pipe 
 
 Strainer and Check Valve. 
 
 ^DC 93 /DC 92 
 
 /DC 94 //DC 72 DC I 
 ' /DC 95// DCM9 /DCl 
 
 DC 120 
 
 exceeds that in the brake pipe the engine brake will set 
 and stay set. 
 
 To operate the locomotive brake automatically leave 
 the straight air brake on release position and make the 
 proper brake pipe reduction with the automatic brake 
 valve. When releasing avoid overcharging the engine 
 auxiliary by leaving the brake valve on full release too 
 long as when you go to running position the drop in 
 brake pipe pressure may set the engine brake. If the 
 engine brake is to be held set and the train brake released 
 go to full release and stay there a few seconds till all 
 triples release, then go to holding position, this will 
 not overcharge the brake pipe and will hold the locomotive 
 brakes set, because air from control reservoir cannot 
 escape after its triple goes to release till the brake valve 
 is put in running position. When the straight air brake 
 is used leave the automatic brake valve on running posi- 
 tion and apply and release the engine brake with the 
 straight air valve. To release the engine brake after it 
 is set automatically without releasing the train brake also, 
 
QUICK ACTION TRIPLE VALVE 231 
 
 use the hand release valve or bleeder that is connected to 
 control reservoir by pipe CR ; by bleeding this reservoir 
 piston 2 will be moved to open exhaust valve 7. The 
 straight air brake valve will not release the engine brake 
 when set automatically, the double throw check valve 
 will prevent it. 
 
 At any time when set automatically the engine brake 
 can be released by holding the bleeder open, but it has 
 no effect when set by straight air as the double check 
 valve will close the opening from the cylinders to the 
 control valve. 
 
 THE QUICK ACTION TRIPLE VALVE 
 
 The Quick Action Triple Valve is used on passenger 
 and freight cars and some passenger tenders. The one 
 shown in section is the older type of freight car triple. 
 The passenger triple valve for 12, 14 and 16-inch brake 
 cylinders has the graduating valve 48 located on top of 
 slide valve 38, and the service port through valve 38 as 
 well as in its seat, the vent valve piston has the port 
 F through the stem 129. The new type of freight triple 
 also has the vent valve piston made like the passenger 
 triple. These triples are shown in Plate R-24. 
 
 As some of the moving parts are at right angles to 
 each other, this cut does not show them as clearly as the 
 diagrammatic views. The same reference numbers and 
 letters are used in both illustrations. Referring to page 
 196, the triple valve body 125 contains the two bushings 
 in which main piston 128 and the valves 38 and 48 move; 
 126 is the front cap which contains vent valve 71 and its 
 spring 132; it also holds the stem of 129 in position. The 
 vent valve seat or "middle section" 130 makes the cap 
 for the cylinder of the triple piston 128. 127 is the side 
 cap and covers the quick-action valve piston 137. Main 
 piston 128 is extended so that it forms a cylinder in 
 which another piston, 129, is fitted, the stem of which 
 passes through 130 and is held from moving to the right 
 
OPERATION OF QUICK ACTION TRIPLE 233 
 
 by a clip or piston stop 142, so that when piston 128 
 moves to release position vent valve piston is in its normal 
 position, and a chamber, G, is left between the two 
 pistons. A small port F through piston 129 allows brake 
 pipe air to pass in and out of chamber G. This port is 
 of such a size that when piston 128 moves slowly to the 
 left in a service application, the air in G can pass out 
 to the brake pipe side of piston 129, and piston 129 will 
 remain stationary with regard to 130 and vent valve 71, 
 as shown in service position. This vent valve is held on 
 its seat by the pressure of the brake pipe air and 
 spring 132. 
 
 In a graduated service application when the brake pipe 
 pressure is reduced in A the auxiliary pressure in the 
 auxiliary side moves piston 128 towards the decreasing 
 brake pipe pressure, first closing the feed port B and 
 moving graduating valve 48 with the piston. As soon as 
 the lost motion between the piston shoulders and exhaust 
 valve 38 is taken up valve 38 moves and closes the exhaust 
 port so no brake cylinder air can escape to the atmosphere. 
 The port to the brake cylinder under valve 48 is next 
 opened, and air from the auxiliary flows to the cylinder, 
 applying the brake. When the flow of brake pipe air out 
 of the brake valve stops, the reduction in A also stops, 
 and as valve 48 is still open the auxiliary pressure soon 
 gets lower than that of the brake pipe so piston 128 is 
 moved to the right and closes valve 48, but does not move 
 valve 38 ; this holds the brake set. Another brake pipe 
 reduction produces the same movements of the piston and 
 valves and so on till the brake pipe reductions make the 
 pressure lower than that of the auxiliary, when the 
 piston will not move back to close the graduating valve 
 48. To release the brake the brake pipe pressure is raised 
 higher than the auxiliary, this moves piston 128 and valves 
 38 and 48 to release position, covering the service port 
 and opening the exhaust port. 
 
 The triple piston 128 makes a full stroke in either 
 service or emergency application, the edge of cylinder 128 
 

 j>>42 
 
 
 
 CJ 
 
 
 7 
 
 cd 
 
 c 
 
 cd 
 
 <u 
 
 n^ 
 
 CU 
 
 C 
 
 U o 
 
 <U 
 
 
 ^42 
 en 
 
 
 <U 
 
 cd 
 
 cd 
 
 
 £ 
 
 > 
 
 
 ^ 
 
 <u 
 
 en 
 
 
 42 
 
 
 
 
 
 1h 
 
 
 
 a 
 
 o 
 
 42 
 
 Q. 
 
 Ed 
 
 bo 
 3 
 
 <Tj 
 
 (h 
 
 O 
 
 
 CU 
 
 u 
 
 
 43 
 
 42 
 
 Cd 
 
 ^ 
 
 u 
 
 > 
 
 U 
 
 
 
 > 
 
 *cd 
 
 
 
 
 a 
 
 cd 
 
 <u 
 
 42 
 
 > 
 
 42 
 
 > 
 
 CU 
 
 42 
 
 O 
 
 
 
 
 cd 
 
 MH 
 
 <u 
 
 > 
 
 o 
 
 en 
 
 u 
 
 J a> 
 
 +J 
 
 O 
 
 a 
 
 u 
 
 o 
 
 
 
 
 u 
 
 
 <u 
 
 -4-» 
 
 cd 
 
 42 
 
 
 
 
 g 
 
 o 
 
 
 o 
 
 '■♦j 
 
 £ 
 
 *+J 
 
 u 
 
 O 
 
 a 
 
 cu 
 
 42 
 
 cd 
 
 en 
 
 en 
 
 
 CU 
 
 5 
 
 6 
 
 CU 
 
 42 
 
 a* 
 
 o 
 
 <u 
 XI 
 
 a 
 42 
 
 bO 
 
 *+H 
 
 42 
 
 '§ 
 
 o 
 
 "ti 
 
 "o 
 
 en 
 
 £ 
 
 '—> 
 
 £ 
 
 r- 
 
 en 
 
 t V 
 
 5 
 
 G 
 
 '> 
 
 C#3 
 
 
 u 
 
 cd 
 
 T3 
 
 cd 
 
 E 
 
 c 
 
 cd 
 
 en ^ 
 
 £ 
 
 u 
 
 1 § 
 
 cd 
 
 >, 
 
 2 5 
 
 »-. en 
 
 bo^ 
 
 .5 
 
 • •» 
 
 cd O 
 
 •o 
 
 <u 
 
 c 
 
 cu 
 
 <u ■ 
 
 G J2 ^ 
 
 
 G 
 
 42 
 
 +-» 
 
 bo. 
 
 -♦-: 
 
 c 
 
 cd "D 
 
 u 
 
 <U 42 
 
 
 CJ 4-« 
 
 
 en 
 
 *•«« 
 
EMERGENCY APPLICATION 235 
 
 striking the leather gasket 133, so that no graduating 
 spring is used to assist in stopping the triple piston in the 
 service position, and the piston does not get any assistance 
 from a graduating spring when starting from emergency 
 or full stroke towards release position. 
 
 If the reduction in brake pipe pressure is made so 
 suddenly that the air in chamber G can not pass through 
 port F fast enough to equalize with the brake pipe reduc- 
 tion, the pressure of air in G will move piston 129 over at 
 the same time piston 128 moves. The stem of 129 will 
 push vent valve 71 away from its seat, as shown in the 
 emergency application; brake pipe air from the chamber 
 around valve 71 can flow rapidly into passage H, and 
 thence against the quick-action piston 137. This in its 
 turn is moved to the right by the pressure of brake pipe 
 air and quick-action valve 138 is unseated, opening a large 
 passage for auxiliary air to flow through K into L — L, 
 forcing check valve 117 off its seat ; the air also passes into 
 the brake cylinder through the usual opening at the grad- 
 uating valve. No air from the brake pipe reaches the 
 brake cylinder, only that from the auxiliary, but the 
 auxiliary air passes through such large ports K and L 
 that the equalization between the auxiliary and cylinder 
 is almost instantaneous after valve 138 is opened. As 
 soon as these pressures have equalized, check valve 117 
 closes and prevents brake cylinder air flowing back into 
 L and thence around the stem of piston 137 to the atmos- 
 phere. In the meantime air in chamber G has equalized 
 through port F so that spring 132 can push vent valve 71 
 and piston 129 to their normal positions. When vent valve 
 71 seats, no more air flows from brake pipe to passage 
 H ; air escaping from ports M and J at once reduces the 
 pressure on piston 137, which is moved to the left, its 
 normal position, by the stiffness of spring 140. Valve 
 138 is closed and no more air can pass from the auxiliary 
 into L, and all the quick-action parts of the triple valve 
 are returned to their normal positions. Piston 128 having 
 made a full stroke, valve 48 is open so that auxiliary air 
 
236 EMERGENCY APPLICATION 
 
 can pass into the brake cylinder and keep the pressures 
 equalized. With 70 pounds auxiliary pressure and the 
 standard piston travel the equalization is the same for 
 full service and emergency applications, 50 pounds per inch. 
 
 Venting the brake pipe air to the atmosphere past valve 
 71 and through ports M and J, should reduce its pressure 
 below that in the auxiliary; this will hold piston 128 in 
 service position. 
 
 The sudden venting of brake pipe air to the atmosphere 
 at this triple makes a sudden reduction at the next triple, 
 which in turn operates quick-action, and so on from one 
 triple to another to the end of the train; this is called the 
 "serial" action. 
 
 If there are, close to the head end of the train, several 
 triple valves cut out, or defective triples that do not oper- 
 ate the vent valve so as to vent enough air from the brake 
 pipe, or cars with brake pipe only, the sudden reduction 
 may not extend far enough to affect a quick-action triple 
 so it works quick-action and continues the sudden serial 
 reduction. About three "cut-out" triples next the engine 
 is the limit to have the quick-action "jump over." At the 
 rear end of the train the quick-action will jump more 
 than three cars, because the volume of brake pipe air 
 behind these defective triples is less than when they are 
 near to the head end of the train. 
 
 This type of triple valve does not send any brake pipe 
 air to the brake cylinder; the brake cylinder pressure is 
 the same with either a full service or an emergency appli- 
 cation; so that the same increase of brake pipe pressure is 
 required to move the triple valve to release position. 
 When brake pipe pressure is restored so that it is greater 
 than auxiliary pressure, or the auxiliary pressure has 
 leaked down, or been bled out, brake pipe air passing 
 through port F into chamber G moves piston 128 and 
 valves 38 and 48 to release position; this closes the service 
 port, opens the exhaust port to release the air from the 
 brake cylinder, and opens feed port B to recharge the 
 auxiliary. 
 
IMPROVED QUICK ACTION TRIPLE VALVE. 
 for 12 and 14 Inch Passenger Cylinders. 
 
 PLATE R 24. 
 
238 TRIPLE VALVE OPERATIONS 
 
 If the piston 128 is in lap position, the volume of air 
 in chamber G is so small that in an emergency reduction 
 of brake pipe air, the pressures can equalize through port 
 F and piston 129 will rarely move. If piston 128 is in 
 service position, it is at the end of its travel and can not 
 move any further. Therefore, after pistons 128 in the 
 triples have responded to a service reduction, no matter 
 how light, the quick-action parts of these triples will not 
 move and a sudden serial action of these triples will not 
 take place ; only a heavy service application. If the 
 general rule to allow the air to pass out of the brake pipe 
 at the brake valve or conductor's valve in cases of emer- 
 gency or danger is promptly obeyed, all brakes that oper- 
 ate will be applied with the greatest power and in the 
 shortest time possible under the conditions. 
 
 The passenger car triple shown in Plate R 24 has the 
 graduating valve 48 on top of the exhaust valve 38 instead 
 of at the end as shown in the next cut of R-6. Valve 48 
 is fitted into a notch in the piston rod so that it moves 
 with the piston 128, having its seat on top of valve 38. 
 When the triple piston makes its first movement in a 
 graduated application, valve 48 uncovers the air port 
 through valve 38 and allows auxiliary air to pass into 
 this port, although air cannot pass into the brake cylinder 
 till the exhaust valve has moved far enough to open the 
 ports into the cylinder. Then when the triple piston 
 moves back to lap position, valve 48 moves across the top 
 of 38 and covers the air port; the lost motion between 
 the ends of valve 38 and the shoulders on the piston rod 
 allows the piston and valve 48 to move without moving 
 38. In this triple R-24, the passages from the auxiliary 
 to the brake cylinder through the quick-action ports of the 
 triple are much larger than in the older form, so that 
 auxiliary and brake cylinder pressures equalize much 
 quicker. 
 
 The improved freight triple valve, R-6, is shown in 
 emergency positions, vent-valve piston is moved down so 
 that the opening of port F through the stem is inside the 
 
TRIPLE VALVE DEFECTS 239 
 
 bushing of the center piece 130. This covering of port F 
 chokes and retards the flow of air out of chamber G so 
 that the vent-valve piston can not return to its normal 
 position so quickly. It thus holds vent-valve 71 away 
 from its seat longer, which makes a heavier reduction in 
 brake pipe pressure. In all the later triples check valve 
 117 and quick-action valve 138 have rubber seats, and port 
 F is in the stem of piston 129. 
 
 This later style of port F operates the same as the port 
 through the piston, in each style the air from G can pass 
 to the brake pipe the full size of port F. 
 
 DEFECTS OF QUICK ACTION TRIPLE 
 
 If vent valve 71 leaks, or is held off its seat, there will 
 be a blow at the round port M, and sometimes at the two 
 square ports J ; also, the brake may not release as brake 
 pipe pressure can not be raised enough to move triple to 
 release position. If the vent valve piston stem 129 is bent 
 or the piston sticks in the cylinder of 128, valve 71 will 
 be held open. This piston stem 129 and the cylinder of 
 128 are easily damaged by improper handling, and should 
 be carefully handled when taken apart. A small leak at 
 valve 71 will show at the round hole M. If there is a 
 blow at the square ports J in the triple shown in Plate 
 Q-6, and not at M, or at N in the triples shown in R-6, 
 air is probably coming from the quick-action valve 138 
 and thence past the stem of 137, which is not an air tight 
 fit in the cast iron body of the triple. If the air passing 
 by valve 138. can not go by stem 137, it will, when the 
 triple is in release position, pass check 117 and out the 
 exhaust port or pressure retainer, or leakage groove. A 
 leaky packing ring in piston 128 will affect the prompt 
 movement of this piston to release position, as the air 
 can leak by this defective ring and equalize the auxiliary 
 with the brake pipe without moving the triple piston. A 
 leak by this ring will not affect the quick-action operation 
 of piston 129. If either of these rings are fitted too tight, 
 
"240 TRIPLE VALVE DEFECTS 
 
 this particular triple piston may not move when the others 
 do in the initial reduction of a service application, and 
 when it does move it may cause quick-action at this 
 triple only. If the packing ring in piston 129 leaks, the 
 air in G can pass out by this ring and this triple is not 
 likely to go into quick-action. 
 
 A leak under the seat of valve 38 will allow auxiliary 
 air to blow out the exhaust steadily. If under valve 48 in 
 the triple shown in Plate Q-6, it will blow at the exhaust 
 when the triple is in release position. With the triple 
 shown in R-24 it will leak in lap position only, and 
 then into the brake cylinder. If the packing ring in either 
 piston 128 or 129 is too tightly fitted or gritty, the triple- 
 may work slower than the others, and get quick-action 
 with a moderate service reduction; this will vent a little 
 brake pipe air to the atmosphere at that triple, but will 
 not cause any other New York triples to work quick- 
 action. If the stem 129 is bent or cylinder of 128 is bent 
 or damaged, it may produce the same effect. This defec- 
 tive triple can usually be located by the flash of air from 
 ports M and J towards the ground which will blow the 
 sand or dust. This brake may release at once if the 
 pressure in the brake pipe is not reduced at that time 
 below that at which that auxiliary and brake cylinder 
 equalizes. 
 
 Sand works into the ports M, N and J and may cause 
 the quick action piston 137 to stick after a quick-action 
 application ; this will hold valve 138 open so auxiliary air 
 will leak away. 
 
 Leaks by the gasket between the triple and the aux- 
 iliary on a freight brake, or the triple and the cylinder 
 head on a passenger brake allowing auxiliary air to pass 
 to the cylinder, will give a steady blow at the exhaust 
 port while the triple is in release position. 
 
 If the port F has been enlarged or the packing ring in 
 piston 129 is a poor fit, so it leaks, this triple may not go 
 into quick-action when the sudden brake pipe reduction 
 is made. 
 
COMPENSATING VALVE 
 
 241 
 
 The Compensating Valve is used in high speed service 
 and is designed to reduce gradually the high brake cylin- 
 der pressure in an emergency application with 110 pounds 
 in the brake pipe and auxiliary to 60 pounds, when the 
 valve will close and allow no more air to escape through 
 it from the cylinder. 
 
 THE COMPENSATING VALVE 
 
 It consists of a piston, 100, that moves in a cylinder or 
 bushing with several small ports in its side, in normal 
 position the piston covers them so no air can pass out the 
 
242 OPERATION OF COMPENSATING VALVE 
 
 ports. Below this piston is a diaphram and plate fastened 
 to the piston that prevents the passage of air either way. 
 The piston is held up in normal position by a stiff spring 
 11, the tension of the spring is adjusted by the nut 12, a 
 cap nut 13 makes an air tight joint at the bottom of the 
 spring box, screwed into the side of the spring box is a 
 check valve 85, containing a valve 86 with a small port a 
 drilled through it. 
 
 The brake cylinder is connected above the piston at A; 
 a connection is made to the check valve case 85 from the 
 passage H in the side of the New York quick-action triple 
 valve. At any application of the brake air from the cylin- 
 der comes into A and gives its pressure to the piston, if 
 this pressure is any greater than the resistance of spring 
 11 piston 100 will move down and uncover the air ports in 
 the side of the bushing; this allows cylinder air to escape 
 and reduce its pressure till spring 11 has power to force 
 piston 100 up and close the ports. A thin leather gasket 
 on top of piston makes a tight joint against a shoulder of 
 the bushing so no air can leak out till the piston moves 
 down. 
 
 When an emergency action of the brake is made, brake 
 pipe air from the quick-action triple comes through a pipe 
 into the check case 85, forces valve 86 off its seat and 
 equalizes in chamber B in the spring box. Spring 87 seats 
 valve 86 so the air in B is confined there, but can grad- 
 ually flow out through the small port a in the check valve. 
 Its pressure comes against the diaphram under the piston 
 and is added to the strength of spring 11, holding piston 
 100 up against a stronger pressure of the cylinder air than 
 the spring alone could. This prevents the cylinder air 
 from blowing out at this valve till the air in B has had 
 time to escape and it then blows down slowly. In this 
 manner it compensates for the change in braking power 
 as the speed of the train reduces. This matter of a change 
 in braking power with a change of speed has been dis- 
 cussed in the chapter on the High Speed Brake. 
 
 The port where the cylinder air enters the valve at A 
 
TYPE J TRIPLE VALVE 243 
 
 is restricted so the air can not flash into A at a high 
 pressure, which aids in graduating the flow of air from 
 the cylinder during an emergency application when the 
 110 pound auxiliary pressure is used. 
 
 These openings are of different sizes for different sized 
 brake cylinders to make the small ones blow down at the 
 same rate of time with the large ones. 
 
 TYPE d TRIPLE VALVE 
 
 Full Release. 
 
244 OPERATION OF TYPE J TRIPLE 
 
 The type J triple here shown in two sectional views 
 and a diagrammatic view is for high duty passenger 
 service, it is both quick-action and quick-service and by 
 the use of a supplementary reservoir of about twice the 
 volume of the regular auxiliary reservoir ; the quick re- 
 charge after a service application, a graduated release of 
 the brake cylinder air and a high pressure at the emer- 
 gency application are secured. 
 
 Referring to the diagrammatic view of the release and 
 charging position, air from the brake pipe passes in the 
 regular way around piston 10, through feed groove D 
 into E and the auxiliary, brake pipe air also passes bv 
 check valve 1 (this valve is 139 in the sectional cut), 
 into chamber F, then through port G into E, so the aux- 
 iliaries are charged from two sources. Port G is of the 
 proper size for the reservoirs it is to charge, port D is 
 small, it is for equalizing the pressures during slight 
 fluctuations in brake pipe pressure. Port H through 
 graduating valve 2 registers with port I through slide 
 valve 3 and port J in the seat so the supplementary is 
 charging at the same time with the service auxiliary. x\ir 
 from the brake cylinder can pass out through ports Q, 
 T, cavity W, ports X and Y. The safety valve is con- 
 nected to the brake cylinder at port Q and is set at 60 
 pounds ; the blow-down attachment that operates in an 
 emergency application only is shown in the lower part of 
 the safety valve. 
 
 In a quick-service application, piston 10 closes feed 
 groove D, graduating valve 2 is moved back so cavity W 
 no longer connects ports T and X, this closes the exhaust, 
 port I is covered so no more air can pass to and from 
 the supplementary, port R registers with S in valve 3, 
 valve 3 next moves so ports G and K register as well as 
 partly opening S to Q. Auxiliary air flows through R, 
 S and Q to the cylinder ; brake pipe air flows from 
 chamber F in a small volume through G, K, L, M and N 
 in between pistons 5 and 8; these pistons are not air 
 tight so the air passes into Q without moving them, this 
 
OPERATION OF TYPE J TRIPLE VALVE 245 
 
 flow of air from the brake pipe makes a light local reduc- 
 tion that affects the next triple so it moves to service 
 position quicker than with the brake valve reduction 
 alone. When the reduction at the brake valve stops and 
 piston 10 moves back to lap it moves valve 2 only and 
 laps port S from the auxiliary and port K so no more air 
 passes to the brake cylinder. In a full service with a 
 short train valve - 3 is moved far enough to lap ports G 
 and K so no air comes from the brake pipe ; ports S and 
 Q are opened wide, thus a larger amount of air can pass 
 from the auxiliary to the cylinder at each triple with a 
 short train than with a long one. 
 
 In a restricted release, the brake pipe is recharged a 
 few pounds above the auxiliary and the brake valve then 
 lapped. Piston 10 will move both slide and graduating 
 valves to release position, opening exhaust ports from Q 
 around to Y; the recharging port G allows air to flow 
 from the brake pipe; and ports J, H and I allow air to 
 flow from the supplementary. This air from the sup- 
 plementary will raise the pressure in E above that in C 
 so piston 10 will move back closing port D, the graduating 
 valve 2 will lap ports H and I so air can no longer flow 
 from the supplementary and pressure in E will not rise 
 higher, exhaust ports T and X are lapped by cavity 
 W moving away from T. As main slide valve 3 will not 
 be moved in this operation ports T and X will still register 
 with Q and Y and air from the cylinder can pass out 
 very slowly through the small port Z, connecting T and X, 
 this allows air to exhaust from the cylinder slowly as 
 long as valve 3 remains in this position. In the emer- 
 gency application, piston 10 and valves 2 and 3 make a 
 full travel at once, port Y is* open to Q so that auxiliary 
 air flashes into the cylinder through a large port, port N 
 is uncovered by this movement of valve 3 so auxiliary air 
 passes between pistons 5 and 8. Piston 5 moves to the 
 left and opens emergency valve 7, brake pipe flashes into 
 Q and the cylinder ; piston 8 opens valve 9 so air from 
 the supplementary in U can equalize through passage Q 
 
246 
 
 THE K-4 TRIPLE VALVE 
 
 with the cylinder and service auxiliary giving a much 
 higher braking power than in the service application. 
 
 The Blow-down valve shown in the bottom of the 
 safety valve case has moderate sized ports Bl around it 
 so in a service application the air from the cylinder can 
 pass around 12 without moving it. In an emergency 
 application the air comes from Q so fast that it raises 
 valve 12, makes a tight joint at its top edge, this prevents 
 cylinder air getting to the safety valve during an emer- 
 gency application. In operating the J triple to make a 
 gradual release charge the brake pipe sufficient to move 
 piston 10 and its valves to release position, then lap the 
 brake valve, the brake will release slowly through port Z. 
 To have it release faster, recharge the brake pipe again 
 to move piston 10 and valve 2 then lap brake valve again, 
 this will open exhaust port wide for a short time, you 
 can thus release the brake by successive steps down to 
 zero. See explanation of question 55. 
 
 QT346 
 QT230. 
 
 The K-4 Triple Valve of the New York Brake Co., 
 in addition to the quick-action and quick-service features 
 already explained in J Triple, has a piston stop 345 and 
 its spring 369; an exhaust piston 339 that during a re- 
 tarded release is moved to the left and chokes the exhaust 
 port with its stem and thus restricts the exhaust. At a 
 
OPERATION OF K-4 TRIPLE VALVE 247 
 
 release, if brake pipe pressure is raised much higher than 
 the auxiliary, it forces triple piston 334 its full travel 
 against the tension of piston stop spring 369, a port in 
 slide valve then allows auxiliary air in at the right of 
 exhaust piston 339 and force it to the left, its stem then 
 chokes the exhaust opening so air passes out slowly. In 
 this position piston 334 makes a tight joint against the 
 bushing, no air will pass it and the auxiliary charges 
 through the port from the brake pipe. When the aux- 
 iliary and brake pipe pressures are nearly equalized, 
 spring 369 will move stop 345, triple piston 334 and its 
 valves 335 and 336 back to free release position, this 
 allows air to pass around piston 334 through feed groove, 
 also opens the space at the right of exhaust piston 339 to 
 the exhaust, so this piston is moved back by its spring 
 347, the exhaust port is then full sized. A leather gasket, 
 358, on the exhaust piston prevents a leak of auxiliary air 
 past the piston while it is held in retarded release posi- 
 tion. See explanation of question 54. 
 
 NEW YORK AIR SIGNAL VALVE 
 
 The Air Signal Valve shown in section on this page 
 has two chambers, A and B, in the upper and lower parts 
 of the valve, separated by a rubber diaphram 12. Air 
 from the main reservoir reduced in pressure at the reduc- 
 ing valve to 40 pounds enters the signal valve from the 
 signal pipe and passes into chamber A through the small 
 opening d which serves to restrict the flow of air into 
 and out of chamber A. From A air passes up around the 
 posts 9 which are firmly attached to the diaphram stem 
 7. Air also passes through the opening a in stem 7, 
 and through the very small hole at b into chamber B. 
 The lower end of stem 7, when in its normal position, 
 makes a tight joint on the top of post 4 around the plug 
 5, so that all air has to pass through b when charging up 
 chamber B. After the signal equipment is charged to 
 
248 
 
 NEW YORK AIR SIGNAL 
 
 the standard pressure, a sudden reduction of pressure in 
 the signal pipe by allowing air to escape at the car dis- 
 charge valve will also reduce the pressure in chamber A. 
 The air in B cannot equalize through b fast enough ; so 
 
 TcstoNAk pire 
 
 SIGNAL VALVE 1903 MODEL. 
 pressure in B will raise diaphram 12, also raising disc 
 valve 10 off its seat at c; air then passes from A to the 
 whistle through e and gives a blast. When diaphram 12 
 raises, the lower end of stem 7 at 11 raises off the post 4, 
 air from chamber B can then pass up through 11 past 
 plug 5, which is taper at its upper end, through passage 
 a in stem 7 and equalize quickly with the air in chamber 
 A. The diaphram at once drops to its normal position 
 with stem 7 resting on post 4, seating valve 10 so no more 
 air passes into the whistle. Air then feeds into A and B 
 till the pressures are equalized with the signal pipe, when 
 another reduction can be made at the car discharge valve 
 and again operate the signal valve. 
 
 The older type of New York Signal Valve is con- 
 structed like the 1903 model, except that the opening a 
 passing through diaphram stem 7 is very small, and air 
 
NEW YORK AIR SIGNAL 
 
 249 
 
 passes through a slowly when charging up B and out of 
 chamber B much slower when the pressure in A is re- 
 duced and diaphram 12 rises ; this causes diaphram to re- 
 main up and hold valve 10 open longer than necessary. 
 
 REDUCING VALVE. 
 
 TO MAIN RESERVOIR 
 
 The disc valve 10 and chamber A are the same in both 
 types of signal valves; the bottom part, chamber B is 
 much larger in the 1903 model than the older type, so 
 there is a larger volume of air in chamber B of the 1903 
 valve. 
 
 The 1903 model charges up chamber B slowly; when 
 diaphram 12 raises, air equalizes from B into A very 
 quickly, thus giving a quick closing of disc valve 10. 
 
 The reducing valve used with the New York signal 
 apparatus is shown in section. Diaphram plate 6 is held 
 down by a regulating spring 9 when there is less than 
 standard pressure in A. This in turn holds supply valve 
 5 off its seat so that main reservoir air entering at 4 can 
 pass into A and through b into the signal pipe, charging 
 it. A rubber diaphram 7 makes an air tight partition 
 between the air in A and the outside air. The small 
 
250 REDUCING VALVE OPERATION 
 
 holes v in the spring cap 3 are to allow any air that may 
 leak past 7 to escape to the atmosphere. When the press- 
 ure in A reaches the standard amount, usually 40 pounds, 
 diaphram 7, stem 6 and nut 8 are raised by the air press- 
 ure against the stiffness of spring 9. This allows spring 
 10 to close supply valve 5 so that pressure in A will not 
 raise any higher. When the opening of a car discharge 
 valve or a leak in the signal pipe or its connections reduces 
 the air pressure, spring 9 forces the diaphram down, opens 
 the supply valve; this allows main reservoir air to feed 
 into the signal pipe again. 
 
 The object of a reducing valve is to maintain signal 
 pipe pressure lower than that used in the operations of the 
 brake, so that operating either the brake or signal will not 
 interfere with the work of the other. The opening past 
 the supply valve is made small so air will pass into the 
 signal pipe slowly in order that a sufficient reduction can 
 be made at the car discharge valve of any car to operate 
 the signal valve. This could not be done if the reducing 
 valve supplied air as fast as the car discharge valve took 
 it out. 
 
 OPERATING THE EQUIPMENT 
 
 When making the initial or first service reduction in 
 brake pipe pressure, to apply the brakes lightly on a train 
 having both kinds of triple valves in operation, no change 
 in the manner or amount of reduction is needed, as both 
 Westinghouse and New York triples, if in good order, 
 will apply their brakes alike. The initial reduction should 
 be from 5 to 7 pounds, depending on the number of air 
 brake cars operated; the length of the entire train and 
 the speed at which it is running. A short train will not 
 need so heavy an initial reduction as a longer train. 
 There will not be so many triple valve feed ports to pass 
 air from the auxiliaries to the brake pipe, which tends 
 to prevent movement of the triple piston, and the volume 
 
OPERATING THE EQUIPMENT 251 
 
 of brake pipe air is less in a short train than in a long 
 one; so the reduction through the brake valve is made 
 quicker, which moves the triples quicker. This in turn 
 passes air into the brake cylinders faster, so the pistons 
 move over the leakage grooves with less loss of air 
 through the grooves. 
 
 On a long train the first reduction may be 7 to 9 
 pounds without giving serious shocks, unless the speed 
 is very slow, in which case it is best to make a lighter 
 reduction. A 5 pound initial reduction will give a cylinder 
 pressure of less than 5 pounds on an 8-inch travel piston 
 with the ordinary triple valves, which will not give any 
 shock to a train. With K triples in the train a 5 pound 
 reduction will give a higher cylinder pressure in their 
 cylinders. If the train is moving fast, the initial reduction 
 can be much heavier; especially in the case of a passenger 
 train. It is advisable to apply the brakes with considerable 
 force when at high speed, the retarding force of the shoes 
 on the wheels is less in proportion than at slow speeds. 
 
 With freight trains, at whatever speed, allow the slack 
 to even up after shutting off steam before applying the 
 brake, then apply it lightly in the case of slow speeds to 
 bunch the train evenly and follow up with other reductions 
 as may be necessary to control the train. Always wait at 
 one reduction till the air has stopped flowing from the 
 brake pipe exhaust of the brake valve and the triples have 
 had a chance to act and the slack to even up before making 
 another reduction. 
 
 When operating the 1902 model New York brake valve, 
 move the handle to first service position notch with a 
 short train, and the air will at once begin to discharge 
 from the brake pipe through an opening in the main 
 slide valve, as the pressure reduces, the cut-off valve will 
 close the opening, it will entirely close when the pressure is 
 reduced the proper amount for that notch; it is not neces- 
 sary to return the handle to lap position. Succeeding reduc- 
 tions may then be made by moving the handle to the next 
 service notches and allowing the valve to graduate the flow 
 
-252 OPERATING THE EQUIPMENT 
 
 of brake pipe air and stop its discharge, or the handle can 
 be stopped between the notches. When the last graduating 
 notch is reached it is expected that a reduction of 20 to 23 
 pounds will have been made in the brake pipe pressure. 
 With a long train it may be necessary to go to the second 
 or third notch in order to get a proper initial reduction on 
 a long train. If quick action is desired at the triples, 
 move the handle to the emergency position for the first 
 reduction and leave it there till the train has stopped or 
 the necessity for the quick stop has passed. This is a 
 general rule for all brake valves and all triples in cases 
 of emergency or danger which must be observed. 
 
 With the older type of New York brake valve, the 
 Vaughn-McKee valve, in order to have the valve cut off 
 the discharge of brake pipe air automatically in a grad- 
 uated application, the valve must have been placed in full 
 release position long enough to discharge all air from the 
 supplementary reservoir to allow brake pipe pressure to 
 move the equalizing piston and the cut-off valve to their 
 normal positions. It must then be moved to running 
 position to recharge the supplementary reservoir from 
 the brake pipe air till it equalizes, after which the piston 
 would operate the cut-off valve in a graduated applica- 
 tion. If the valve was only placed on running position 
 to release brakes and moved to service application, the 
 cut-off valve might be over the graduated reduction port 
 so no air could pass out of brake pipe and it would be 
 necessary to go farther back towards the emergency 
 notch to discharge any brake pipe air. When operating 
 the brake with this valve be sure to go to full release 
 when releasing brakes, then stop on running position an 
 instant if you expect the piston to operate the cut-off valve 
 in a graduated service reduction. The 1902 model brake 
 valve will graduate the flow of brake pipe air in a service 
 application, as it automatically discharges and recharges 
 the supplementary reservoir when at lap position or 
 towards release. As the only proper position for the 
 brake valve at the moment of releasing all brakes on any 
 
OPERATING THE EQUIPMENT 253 
 
 kind of a train or engine is full release, this precaution 
 can be observed. 
 
 With a short train or lone engine the brake valve of 
 whatever type can be moved from full release to running 
 position in a few seconds and thus avoid overcharging the 
 brake pipe in case there is a high main reservoir pressure. 
 
 With a long brake pipe, leave the valve in full release 
 about a half second for each car or until the black and red 
 hands of the gauge have equalized at less than the standard 
 brake pipe pressure, usually 70 pounds, then move to run- 
 ning position and leave it there till the next application, 
 unless the train is a very long one, when it is not unusual 
 for a few of the brakes on the head end of the train to 
 apply from overcharged auxiliaries, the head ones charging 
 higher than those on the rear when main reservoir air is 
 flowing rapidly into the brake pipe. If any set, they can be 
 kicked off by going to full release for an instant. The 
 New York brake valve has an excess valve to maintain a 
 difference of pressure between the main reservoir and 
 brake pipe so the instructions about carrying excess press- 
 ure with the Westinghouse D-8 brake valve, found in the 
 previous pages of this book, will apply to the New York 
 brake valve. Questions 19 and 65 refer to this matter. 
 Always use full release position to release brakes with 
 any valve, and it is a vital point in quick recharging of 
 auxiliaries, as when on a hill, to keep the valve in full 
 release as long as possible. 
 
 Many railroads have imperative, iron-clad rules about 
 certain air brake work which are made to prevent careless 
 or unskillful air brakemen from doing considerable dam- 
 age. While only a very few of the men handling the brake 
 may be in the class mentioned, yet the rule must be 
 observed by the skillful as well as the careless ones. 
 One of these rules is : "Do not release the brakes on a 
 long train when running at a slow speed, but come to a 
 full stop first" This speed is usually below eight miles 
 an hour. This rule is made because the shocks to the 
 train caused by the slack running in or out of the train 
 
254 OPERATING THE EQUIPMENT 
 
 quicker than all the brakes can release, is usually certain 
 to break the train in two or more parts. With the use 
 of an additional engine and tender brake, either the 
 Straight Air or the ET brake; retaining valves on engine 
 and tender brakes or cocks so arranged as to hold the 
 engine and tender brakes applied, or sufficient K triples 
 at the head end, the train brake can be released at a slow 
 speed without serious shocks. Retainers depend on tight 
 piston packing and tight joints for their value. If the 
 joints or packing leathers leak, retainers are useless for 
 this purpose. This "iron-clad rule" applies as well to long 
 passenger trains, when consisting of over twelve coaches, 
 a release at slow speed without the use of some device 
 on the engine to hold the slack is almost certain to break 
 the train in two parts. The size of the main reservoir 
 and amount of excess pressure have considerable to do 
 with the ease and certainty of releasing all brakes quickly 
 on a long train; large volume and high excess make the 
 operation sure on a long train. You should remember 
 that there is more difference in the reservoir and brake 
 pipe pressures after a 20-pound reduction than after a 
 5-pound reduction. This may explain the reason for 
 stuck brakes on a long train after a light application. 
 This matter is treated of in questions 12, 61 and 108. 
 One prominent railroad handling long trains of air braked 
 ore cars allows the release of a few brakes at a time when 
 running at a slow speed, instead of coming to a full stop. 
 After a full application or nearly so, when necessary to 
 release a few of the brakes at a time and allow the train 
 to keep moving during releasing, the brake valve is moved 
 from lap to running position for an instant to raise the 
 brake pipe pressure a very little, not over a pound, when 
 a few brakes, usually those near the head end of the train 
 will release. The next time the valve is placed in running 
 position for an instant, brakes will release in various 
 parts of the train; this operation can be repeated till the 
 brake pipe pressure is raised about 5 pounds in all. 
 Between each release allow the slack to even up. If this 
 
TRACING THE AIR 255 
 
 work is skillfully done and the triples are in good order, 
 very few brakes will remain applied after the 5-pound 
 raise in pressure. Then with good stiff excess go to full 
 release and quickly charge the brake pipe up its entire 
 length to ensure that all triples are moved to release 
 position. This process has a much different effect on a 
 train at slow speed from releasing all triples with the same 
 recharge of brake pipe. It also operates better on a train 
 of ore cars which are either all loaded or all empty, than 
 on an ordinary freight train having loads and empties 
 mixed up in the train; for this reason it takes great skill 
 to handle a freight train in this manner. A full release of 
 all triples from one movement of the brake valve at slow 
 speed, usually breaks the train in two; for that reason all 
 roads condemn the practice. In releasing brakes an 
 engineer should know the grades and how they affect the 
 bunching or stretching of a train. 
 
 One of the questions usually asked in an air brake 
 examination is "trace the air through the air brake system; 
 tell where it goes and how it operates the various parts 
 of the equipment." Some air brake instructors ask this 
 question at the beginning of their examination. As a 
 complete answer to this question requires a good knowl- 
 edge of the entire equipment, in this book it is left till 
 the last. 
 
 With the Westinghouse equipment, air from the atmos- 
 phere enters at the inlet or receiving valves of the air 
 pump, when the piston moves in the air cylinder, filling 
 the space left by the piston. As the piston makes a stroke 
 the air in the cylinder that is compressed passes by the 
 discharge valves into the main reservoir and from there 
 to the brake valve, where it is above the rotary valve. 
 In full release position it passes through the direct supply 
 port in rotary into the pocket in the rotary seat, around 
 the partition, up into the large cavity in the lower side of 
 the rotary, then into the brake pipe. At the same time 
 it passes through the feed port in the rotary and the pre- 
 liminary exhaust port into chamber D also through the 
 
256 TRACING THE AIR 
 
 equalizing port into chamber D; main reservoir air goes 
 to red hand of the duplex gage and pump governor and 
 warning port to atmosphere. From chamber D, air goes 
 to the black hand of gage. 
 
 In running position air passes through the running 
 position or feed port into the feed valve and, until the 
 supply valve closes, on into the brake pipe. In this posi- 
 tion air passes from the brake pipe up into the cavity in 
 the rotary and then to chamber D through the equalizing 
 port. With the D-8 or 1899 valve in running position air 
 passes through feed port in rotary to the excess valve; 
 by the excess valve into brake pipe. With D-8 valve brake 
 pipe air goes to the governor, with the other valves, main 
 reservoir air operates the governor. When the governor 
 operates air flows past the diaphram valve in over the air 
 piston and some air passes out the vent port. 
 
 The air in chamber D flows into the brake valve reser- 
 voir with all types of brake valve. Brake pipe air flows 
 back until it reaches an angle cock or stop cock that is 
 closed. It flows into every triple valve that is cut in and 
 connected to the brake pipe, pressing against the bottom or 
 brake pipe side of the triple piston. When this piston is 
 in release position air flows through the feed groove 
 around the triple piston into the auxiliary reservoir till 
 the pressures are equalized. Air also passes up the pipe 
 to the conductor's valve. When the pressures in the brake 
 pipe and auxiliary have equalized at 70 pounds the brake 
 is ready for an application; we will explain a service 
 application first. 
 
 Moving the handle of the rotary to service position 
 first laps the port that admits main reservoir air to the 
 brake pipe, closes the equalizing port between chamber D 
 and the brake pipe and opens the preliminary exhaust port 
 so chamber D air escapes to the atmosphere. This reduces 
 chamber D pressure over the equalizing piston brake pipe 
 pressure then raises this piston, which opens the brake pipe 
 exhaust valve so brake pipe air flows to the atmosphere, 
 reducing the pressure at each triple valve. The triple 
 
TRACING THE AIR 257 
 
 piston moves towards the reducing pressure, closing the 
 feed port, moving the graduating valve to open its port in 
 the slide valve, the slide valve moves so the exhaust port 
 is closed, next opening the air port to the brake cylinder 
 so that auxiliary air flows into the brake cylinder and 
 pushes out the brake piston which sets the brake. See 
 question 37 for the Operation of the Distributing Valve. 
 
 To release the brake, the brake valve is placed in full 
 release position; main reservoir air passes into the brake 
 pipe as already described. This moves the triple valves 
 to release position, closing the air ports to the brake 
 cylinder, opening the exhaust port so the air can flow 
 from the cylinder to the atmosphere and opening the 
 feed groove so brake pipe air can flow into the auxiliary. 
 Air also flows into chamber D and brake valve reservoir. 
 
 To release the ET brake the brake valve must be in 
 running position, or the independent valve in release 
 position. 
 
 If a retaining valve is used, brake cylinder air, after 
 leaving the exhaust port, passes through a pipe to the 
 retainer, when this valve is in release position the air 
 passes directly out. If the valve is in retaining position 
 air pressure raises the valve and passes up into the case 
 of the retainer and then out through the small opening 
 in the case till the pressure drops to 15 pounds, when 
 the valve seats and holds the air in the brake cylinder till 
 the retainer is turned to release position. 
 
 When making an emergency application of the brake 
 the brake valve is placed in emergency position. Brake 
 pipe air passes out very rapidly through the direct exhaust 
 port at the same time chamber D air passes out at the 
 preliminary exhaust port of the automatic brake valve. 
 Air passes out of the brake pipe so rapidly that the triple 
 valve cannot reduce auxiliary pressure as shown in service 
 application, auxiliary air pressure moves the piston full 
 stroke at once, auxiliary air passes by the removed corner 
 of the slide valve through emergency port and on top of 
 the emergency piston, pushing it down, this opens the 
 
258 TRACING THE AIR 
 
 emergency valve and allows brake pipe air to pass into 
 the brake cylinder, which sudden reduction of brake pipe 
 pressure operates the next triple quick-action and so on 
 throughout the whole train. At the same time auxiliary 
 air passes through the tail port in the slide valve; also 
 some air passes by the emergency piston into brake cylin- 
 der till the pressures equalize. When the brake is set 
 by opening the conductor's valve or by the train breaking 
 in two, the operation is the same. 
 
 In releasing brakes after an emergency application, the 
 flow of air is the same as with a service application. We 
 will add to this answer the signal equipment: The main 
 reservoir air flows through the reducing valve till it 
 reaches a pressure of 45 pounds; if the reducing valve is 
 adjusted for that pressure. Air flows into the air signal 
 pipe back to each car discharge valve. On the engine it 
 passes from the signal pipe into the upper part of the 
 signal valve, over the rubber diaphram into A, it also 
 passes down to the lower part of the valve, up by the 
 stem 10 slowly into chamber B until the pressure equalizes 
 there with the signal pipe. When the whistle is to be 
 operated from the train, the car discharge valve on the 
 car is opened, air passes out of the signal pipe to the 
 atmosphere. This reduces signal pipe pressure, when the 
 reduction affects the pressure over the diaphram in the 
 signal valve, the pressure under the diaphram not being 
 reduced so quickly, air under it in B raises the diaphram 
 and with it the valve 10, so that air flows out there to the 
 whistle, giving a blast. When the valve 10 is raised, air 
 in B flows past the flattened sides of this stem to the 
 whistle; this quickly reduces the pressure in B and the 
 diaphram drops, pushing valve 10 to its seat so no more 
 air passes to the whistle. As soon as the brake pipe 
 pressure falls below 45 pounds the reducing valve opens 
 and begins to feed main reservoir air into the signal pipe 
 slowly, as the opening through the valve is restricted or 
 choked. If the air could pass into the signal pipe at the 
 reducing valve as fast as it can pass out at a car discharge 
 
TRACING THE AIR 259 
 
 valve, no reduction would be made in the signal pipe 
 pressure. 
 
 With the New York brake, the course of the air is a 
 little different. Air flows from the atmosphere through 
 the receiving valves into the air cylinders as the air 
 pistons move up and down. The air in the high pressure 
 air cylinder goes direct to the main reservoir when it is 
 compressed. The air in the low pressure air cylinder, 
 when compressed, passes into the high pressure air cylin- 
 der and from there into the main reservoir, thence to the 
 brake valve around and on top of the main slide valve; 
 main reservoir air goes to the red hand of the gage and 
 brake pipe air to the black hand. If a single governor 
 is used it is operated by brake pipe air, if a duplex gover- 
 nor one side by brake pipe air and the other by main 
 reservoir air. When in release position it passes directly 
 into the brake pipe and from the brake pipe into chamber 
 D and the supplementary reservoir with the 1902 model 
 valve. With the old style brake valve on release position 
 the air in the supplementary reservoir and chamber D 
 passes out through a small cavity in the slide valve to the 
 atmosphere; this allows brake pipe pressure to move the 
 equalizing piston to its normal position. On running 
 position the main reservoir air passes by the excess valve 
 and then into the brake pipe ; brake pipe air passes into the 
 supplementary reservoir with the brake valve in this 
 position. 
 
 The brake pipe air passes back through the brake pipe 
 to each triple valve that is cut in. At the triple valve the 
 air passes through the port F in the vent valve piston and 
 if the main piston is not already in release position, 
 moves it there. Air then passes through the feed groove 
 into the auxiliary until the pressure there has equalized 
 with the brake pipe. With the Automatic Control Valve 
 the course of air is explained at the operation of that 
 valve. 
 
 With a service application, the slide valve in the brake 
 
260 TRACING THE AIR 
 
 valve is moved till the service port is open, brake pipe air 
 then flows direct to the atmosphere until its pressure is 
 reduced so the pressure of the air in the supplementary 
 reservoir can move the piston, closing the cut-off valve 
 and stopping the escape pf brake pipe air. 
 
 This reduction of brake pipe pressure extends to each 
 triple, auxiliary air pressure moves the triple piston, 
 graduating valve and slide valve; first closing the feed 
 groove, next the exhaust port and then opening the air 
 port so air passes from the auxiliary to the cylinder. 
 The air in the space G, between the main triple piston 
 and the vent valve piston passes out through port F so 
 the vent valve piston does not move in a service application. 
 
 In an emergency application the slide valve in the 
 brake valve is moved to emergency position. Brake pipe 
 air passes rapidly out through the large ports in the slide 
 valve, reducing brake pipe pressure so rapidly that the 
 triple pistons make a quick stroke. As the air between 
 the two pistons cannot pass through port F quickly enough, 
 the vent valve piston moves with the main piston, unseats 
 the vent valve; this allows brake pipe air to flow to the 
 atmosphere. The air also pushes against the quick action 
 piston, moving it over and with it opens the quick-action 
 valve, which permits auxiliary air to flow through the 
 passages into the cylinder, the check valve preventing this 
 air from flowing back from the cylinder. Auxiliary air 
 also flows into brake cylinder through the service port at 
 the graduating valve. In releasing the brake the flow of 
 air has already been described. 
 
 The course of air through the signal equipment is the 
 same as described with Westinghouse signal, except that 
 air passes, from chamber A to chamber B through a small 
 port b when charging up the signal valve, and out of B 
 around the plug 4 to chamber A, when the signal valve 
 operates. 
 
AIR BRAKE EXAMINATION QUESTIONS 
 
 1. What are the essential parts of the automatic 
 brake? What does each part do? 
 
 2. Can you trace the course of the steam through the 
 steam end of the air pump? Can you trace the course of 
 the air through the pump? 
 
 3. How should the pump be started and lubricated ? 
 
 4. If the pump stops after working good for a time, 
 where is the trouble likely to be? 
 
 5. If it makes a quick stroke one way and a slow 
 stroke the other, where is the trouble likely to be? 
 
 6. What are the principal causes for a pump running 
 hot? 
 
 7. If the main reservoir is partly filled with water, 
 which will it affect the most, setting or releasing the 
 brake? Why? How often should it be drained? 
 
 8. What might prevent the governor shutting off the 
 steam and stopping the pump when maximum pressure is 
 obtained? 
 
 9. Where would you look for the trouble if governor 
 stops the pump at much less than standard pressure? 
 
 10. How do you adjust the governor with the ET 
 brake ? 
 
 11. Should you test the engine and tender equipment 
 for leaks? 
 
 12. How do you test for leaks in main reservoir and 
 pipes from pump to brake valve? 
 
 13. What other parts of the equipment gets air from 
 the main reservoir besides the brake pipe? 
 
 14. How do you test for a leak in brake pipe? In 
 signal line? 
 
 15. How do you locate a leak that lets off the brake? 
 
 16. What pressure should you have before testing? 
 
 17. What controls the excess pressure with the H-5 
 and H-6 brake valve? With the F-6 valve? With the 
 New York brake valve? 
 
262 EXAMINATION QUESTIONS 
 
 18. How many kinds of engineer's brake valves have 
 we in service on this road? 
 
 19. Can you trace the air through each of them? 
 
 20. Explain the principle of operation of the engineer's 
 equalizing discharge brake valve. 
 
 21. Describe its operation to apply the brake with 
 service or emergency applications, and in releasing the 
 brake. 
 
 22. Why is excess pressure necessary? Do you need 
 the most with a large main reservoir or a small one? 
 
 23. Is more excess needed to release all the brakes on 
 a long train than on a short one? 
 
 24. How do you regulate the excess pressure with 
 the H type brake valve? With the 1892 model or F-6 
 valve ? 
 
 25. Name the different positions of the brake valve. 
 What extra position has the type H brake valve? 
 
 26. What ports are open and what ports are closed 
 in each position? 
 
 27. Where does main reservoir pressure begin and 
 end? 
 
 28. Where does brake pipe pressure begin and end? 
 
 29. Where does auxiliary pressure begin? 
 
 30. . What is the equalizing port for? Is it open in 
 all positions of the brake valve? 
 
 31. Do leaks in the brake valve affect the operation 
 of the brakes? Explain how. 
 
 32. Do you consider a cut rotary valve or seat 
 dangerous ? 
 
 33. Will using the valve in emergency instead of 
 service application cause this cutting any quicker? Why? 
 
 34. What is the purpose of the small reservoir con- 
 nected to the equalizing discharge valve? 
 
 35. If the pipe leading from valve to small reservoir 
 is broken off or leaking badly, what will you do? 
 
 36. Where is the first air taken from in making a 
 service stop? What port does it blow out of? 
 
 37. Where does it come from? Where next? 
 
EXAMINATION QUESTIONS 263 
 
 38. Does air ever blow out of brake pipe exhaust 
 when releasing the brake? Why? 
 
 39. Do you hear it when releasing brake on engine 
 and tender only? Do you hear it with a train of over 
 two cars? Do you hear it with the H type? 
 
 40. If you are connected to more than two air cars 
 and heard that blow, what would it indicate? 
 
 41. How do you know that the brake valve is working 
 properly? 
 
 42. When applying the brakes can you tell about how 
 many cars are connected with air to the brake valve by 
 the amount of air escaping from the brake pipe exhaust? 
 How do you make this test? 
 
 43. How much do you reduce the brake pipe pressure 
 from 70 pounds to set the brake as tight as possible? 
 
 44. Why will this reduction do that? 
 
 45. What is the difference between a reduction and 
 an application? 
 
 46. Does the length of travel of brake piston have 
 anything to do with the pressure when brake is full set? 
 How ? Explain fully. 
 
 47. In making a service stop why should the brake 
 valve not be moved past the service application position? 
 
 48. Is this movement of the brake valve liable to kick 
 off some of the head brakes? Why? 
 
 49. What is the proper position to place brake valve 
 in after releasing brakes if they are to be set again im- 
 mediately? Why? Explain fully. 
 
 50. What are the functions or uses of the triple valve? 
 
 51. How many forms in use on this road ? Describe 
 each form. 
 
 52. Where does all the air come from that enters the 
 brake cylinder through the plain triple when setting the 
 brake ? 
 
 53. Does all the air that goes into the brake cylinder 
 of a quick-acting brake come from the auxiliary? 
 
 54. Please explain the action of the quick-action triple 
 when used in the emergency application. 
 
264 EXAMINATION QUESTIONS 
 
 55. Can you get the emergency action after a service 
 application? 
 
 56. Does it take a sudden reduction of pressure right 
 at the triple to work the quick-action valves or will a slow, 
 heavy reduction do this? Why? 
 
 57. If three or four cars at the head end of the train 
 do not have quick-action triples working, can you get the 
 emergency application behind these cars by a reduction 
 at the brake valve? How many cars will the quick-actron 
 "jump over?" 
 
 58. What is the function of the graduating valve? 
 
 59. Where is it located and how does it operate? 
 
 60. If the graduating valve leaks on its seat, is the 
 brake connected to that triple liable to release on a partial 
 application? On a full application? Why is this? 
 
 61. What is the function of the graduating stem and 
 spring? 
 
 62. If this spring is very weak or missing, how will 
 it affect the work of the triple valve? 
 
 63. How does the air get from the brake pipe into 
 the auxiliary with the ordinary triple? With the K type? 
 
 64. Why is this port so small? Could the brakes be 
 set and released as certainly on a long train if this port 
 was much larger? Would auxiliaries charge evenly? 
 
 65. In what position of the triple valve is the port 
 open ? 
 
 66. How rapidly does an empty auxiliary charge up 
 to 70 pounds with 70 in the brake pipe? 
 
 67. How rapidly from 50 pounds up to 70 pounds? 
 
 68. What regulates the time of charging each different 
 sized auxiliary? 
 
 69. If one auxiliary is charged up higher than another 
 is the brake likely to creep on? Is it liable to take place 
 when coupling up an air brake train? Explain why. 
 
 70. Why is it dangerous to apply and release the brake 
 repeatedly in making one station stop? 
 
 71. Does this apply to a release and second applica- 
 
EXAMINATION QUESTIONS 265 
 
 tion at a slow speed on slippery track? With a passenger 
 train? Witlr a freight train? 
 
 72. Do you understand that brake- cylinders have 
 leakage grooves? Where are they located and how long 
 are they? What are they for? 
 
 73. Do you allow for them when setting the brake? 
 How? 
 
 74. As a rule how much reduction in brake pipe 
 pressure is necessary to ensure that brake piston goes 
 past the leakage groove? • 
 
 75. Does a long train require more than a short train ? 
 Why? 
 
 76. What should be done after coupling to an air brake 
 train before pulling out? 
 
 77. .What pressure should you have in brake pipe and 
 auxiliaries before testing the brake? 
 
 78. How do you know when you have 70 pounds m 
 the auxiliaries? 
 
 79. What tests of air equipment are called for by our 
 rules? Explain fully how these tests should be made. 
 
 80. Are you required to test retaining valves? How 
 is this done? 
 
 81. If a brake is broken or disabled, how will you 
 prevent it working on that car and let the brakes work on 
 other cars? 
 
 82. How do you cut out the brake on engine or 
 tender ? 
 
 83. Is it necessary to release the brake before cutting 
 it out? 
 
 84. How does the length of the piston travel affect the 
 work of the brake? If it is too long? If it is too short? 
 
 85. What is the proper piston travel? For passenger 
 cars? For freight cars? For engine brakes? 
 
 86. How is the slack taken up to secure this adjust- 
 ment ? 
 
 87. Should the triple be cut out before adjusting the 
 levers to avoid injury to the workman in case brake 
 goes on? 
 
266 EXAMINATION QUESTIONS 
 
 88. At what travel should the driver brake piston be 
 adjusted? How is the slack of a six-wheel brake taken 
 up? 
 
 89. What is necessary in order to have all the brakes 
 work alike? 
 
 90. When brakes go on suddenly and are not operated 
 by the engineer, what should you do? To what causes 
 would you assign this? 
 
 91. If an air brake train breaks in two, how do you 
 proceed to get train ready to go ahead again? How do 
 you proceed in case of a bursted hose? How can you 
 help trainmen to locate it? 
 
 92. Would it be necessary in these cases to make a 
 terminal test? 
 
 93. If, after releasing train brake there is a steady 
 leak from the exhaust port of the triple, what is the 
 trouble ? 
 
 94. What precautions must be observed in making a 
 stop with a "part air" freight train? What with a long, 
 "full air" train? 
 
 95. In making a stop with a freight train, when would 
 you let off the brakes to make a smooth stop? Why? 
 
 96. When with a passenger train? Why? 
 
 97. What is the pressure retaining valve, what is its 
 use and how is it operated? Are there several kinds? 
 
 98. How many pounds of air is it intended to close 
 up on and hold in the brake cylinder? 
 
 99. Does the brake release any slower till it gets 
 down to this pressure, and how is it done? 
 
 100. Can you get the emergency action of the brake 
 with the pressure retainers holding 15 pounds? 
 
 101. In descending a grade, how can you best keep a 
 train under control? 
 
 102. When two or more engines are coupled together, 
 which engineer should do the braking? Why? 
 
 103. How will you proceed to give the leading 
 engineer complete control of the train? What should the 
 second engineer do? 
 
EXAMINATION QUESTIONS 267 
 
 104. If there is no cut-out cock on second engine 
 under the brake valve, what should be done? 
 
 105. How does the air signal equipment operate? 
 
 106. What pressure should be carried in the signal 
 line? How do you know you have this pressure? 
 
 107. What causes the whistle to blow each time the 
 brake is released? What makes it repeat the signal? 
 
 108. Will a leak in the train signal pipe affect the 
 working of the whistle? Explain. 
 
 109. Explain the meaning of the signals given by one, 
 two, three and four blasts of the signal whistle. 
 
 110. What changes do you make in the engine equip- 
 ment to carry 110 pounds brake pipe pressure instead of 
 70, for the high speed brake?. For the type L triples? 
 
 111. How many pounds brake pipe reduction in a 
 service application will give a fully applied high speed 
 brake ? 
 
 112. Is it safe to use the emergency application of the 
 high speed brake when running less than thirty miles an 
 hour ? Why. 
 
 113. Explain the action of the high speed reducing 
 valve in service, and in emergency. 
 
 114. What pressures should be in the brake cylinders 
 on the engine and tender when the Straight Air brake is 
 fully applied? 
 
 115. How is this pressure regulated? 
 
 116. Does long piston travel have any effect in reduc- 
 ing this pressure? 
 
 117. What valve closes the exhaust from the brake 
 cylinder to the triple when the Straight Air is applied, 
 and vice versa? Explain its operation. 
 
 118. Is it good practice to use the automatic while 
 the Straight Air is full set on the engine and tender brake? 
 Why?. 
 
 119. Should the Straight Air brake valve be left on 
 lap position while operating the automatic? Why? 
 
 120. How many air pipe connections at the Distribut- 
 
268 EXAMINATION QUESTIONS 
 
 ing valve? Explain where the air comes . from and goes 
 to at each of these connections,.;... 
 
 121. How many pipe connections at .the H-5 brake 
 valve? How many with the H-6? Where does the air 
 come from and go to at each one? 
 
 122. Explain the effect of leaks frbm each of these 
 pipes and tell what you would do in each ease, if any of 
 them break off. How do you locate these leaks? 
 
 123. What is the duty of the equalizing piston and its 
 slide valves in the Distributing valve, and what air press^ 
 ures operate it? 
 
 124. What is the duty of the application piston and 
 its valves and what air pressures operate it? 
 
 125. Why does the engine brake creep on when either 
 brake valve is lapped? How will you, locate this defect? 
 
 126. Will the engine brake stay applied if both brake 
 valves are in running position? Why?: Will it creep on 
 from leaks? 
 
 127. Which brake valve is used to apply the auto- 
 matic brake on train and engine? Which brake valve 
 should be used to operate the engine brake only? 
 
 128. What is the difference in the operation of the 
 engine brake by the Independent brake valve and by the 
 Straight Air brake valve? 
 
 129. Does the safety valve on the Distributing valve 
 control the application chamber pressure when the Inde- 
 pendent brake valve is used?. Or in an automatic applica- 
 tion only? Any difference between No. 5 and No. 6 ET? 
 
 130. What valve regulates the brake cylinder pressure 
 in a full application by the Independent brake valve? 
 
 131. Explain the operation of the excess pressure side 
 of the duplex pump governor. How do you set it? 
 
 132. Is it necessary to move the New York brake 
 valve to positive lap position at a brake pipe reduction, or 
 should the valve be allowed to move itself to automatic 
 lap? Why? 
 
 133. Trace the course of the brake pipe air in the 
 Westinghouse quick-action triple in release, service and 
 
EXAMINATION QUESTIONS 269 
 
 emergency positions. Also do the same for the New 
 York quick-action triple valve. 
 
 134. Explain the retarded release of the K type triple. 
 
 135. Explain the operation of the Westinghouse L 
 type triple? 
 
 136. Explain the operation of the New York Auto- 
 matic Control brake. 
 
INDEX 
 
 Air Pump — 8-inch 24-25-26 
 
 Air Pump— 9^-inch . 7.7 26 to 30 
 
 Air Pump — 1 1-inch 31 
 
 Air Pump — Cross-Compound 37-38-39 
 
 Air Pump— New York Duplex .192 to 199 
 
 Accelerator valve — New York brake 222 
 
 Air Signal — Westinghouse 146-157 
 
 Air Signal— New York 7.247 to 250 
 
 Auxiliary reservoir 22-47-107-136-189 
 
 Automatic slack adjuster 174 to 176 
 
 Air cylinder lubricator 31 
 
 Automatic control— New York brake 225 to 231 
 
 B-6 feed valve m ^ 
 
 B-3 brake valve— New York brake .7 ... . 214 to 219 
 
 Brakes leaking off 22-69-125-156-158 
 
 Brakes creeping on 129 
 
 Brakes sticking 7.7.7.7.7.'. 127-159-254 
 
 Bursted hose 143 
 
 Brake pipe pressure .7 .22-64 
 
 Breaking in two 7 . . 144 
 
 Brake leverage .21-177 to ' 185 
 
 Charging auxiliaries 6-21-22-136 
 
 Cutting out brakes 139-154 
 
 Calculating air pressures 186 to 190 
 
 Compensating valve— New York brake 241 
 
 Definitions 23 
 
 Distributing valve — No. 5 78 
 
 Distributing valve — No. 6 92 
 
 Defective air pump 33 to 36-198 
 
 Defective brake valve 69-72-125-208 
 
 Defective brake 128-130-154-158-159 
 
 Defective governor 42-43 
 
 Defective triple valve 17-113 to 115-154-239 
 
 Defective brake pipe 133 
 
 Defective piston packing 33-35-156 
 
 Defective air signal 147-149-157 
 
 Double heading 98-142 
 
 E. T. equipment — No. 5 73 to 81 
 
 E. T. equipment — No. 6 84 to 100 
 
 Equalizing discharge brake valve 11-55 to 69 
 
 Equalizing reservoir 22-56-69-189 
 
 Excess pressure 52-53 
 
 Emergency application 14 to 17-109-260 
 
 Equalization 5-18-19-186-188 
 
 Examination questions 261 to 269 
 
 F-6 brake valve 54 to 56 
 
PAGE 
 
 F-6 feed valve 58 
 
 Full application 10-23-107 
 
 Governor 41 to 46-200-202 
 
 G-6 feed valve 60-61 
 
 Graduating valve 7-106-113-233 
 
 Graduated application 106-113-233 
 
 H-5 brake valve 73 
 
 H-6 brake valve 87 
 
 Handling trains on grades 141 
 
 High speed brake 163 to 171 
 
 High pressure control 172 
 
 Independent brake valve 77-90 
 
 Inspection of brake equipment 21-48-134-135-153 
 
 J triple valve — New York brake 243 
 
 K type triple valve 116-118-251 
 
 L type triple valve 119 to 124 
 
 Leakage groove 22-106-137 
 
 Leaks in brake pipe 50-129-158 
 
 Leaks in brake cylinder 22-126-156 
 
 Leaks in triple valve 125-154-251) 
 
 Leaks in brake valve 69-72-125-208 
 
 Leaky brake pipe check valve 125 
 
 New York brake valve— 1902 model 251 
 
 Operating the equipment 21-251 to 255 
 
 Overcharging the brake pipe 19-127-130 
 
 Plain triple valve 5-6-7-108-139-154 
 
 Pressure retaining valve 144-152 
 
 Position of brake valve 11-63 to 69-73-75-104-105 
 
 Piston travel : 18-22-138-155 
 
 Pressure on brake piston 18-105-107-138-187-188 
 
 Quick action triple valve — Westinghouse. .15-18-108 to 114 
 
 Quick action triple valve — New York 231 
 
 Quick service triple valve 115-119 
 
 Releasing brakes 9-131-254-257 
 
 Reducing valve 62-148-211-249 
 
 Straight air brake 101 to 104-209 
 
 Slide valve feed valve 60 to 63 
 
 Service application 7-23-107-206-233-251 
 
 Safety valve 85-169-172 
 
 Slack adjuster 174 to 176 
 
 Testing for leaks 49-72-100-125-208-239 
 
 Testing air signal 147-157 
 
 Testing brake valve 69-72-125-208 
 
 Testing the brakes 20-125-134-153 
 
 Two-application stop 19-132 
 
 Trainmen's questions 150 
 
 Tracing the air 255 
 
 Water raising system 160 to 162 
 
MITCHELL'S MODELS 
 
 Are a series of cardboard models or 
 charts, printed, colored and cut so clearly 
 as to show the perfect and defective action 
 of brake valves, triple valves, governors, 
 etc. The relation existing between dif- 
 ferent parts, passages and pieces of the 
 apparatus is clearly shown and the function 
 of each is explained in clear, simple lan- 
 gauge so that after a little study the course 
 of the air can be readily traced. 
 
 No engineer, fireman, trainman, or per- 
 son desiring to qualify for air brake exami- 
 nation can afford to be without a set of 
 Mitchell's Air-Brake Models. They in- 
 sure your getting the necessary knowledge 
 with least expenditure of time and labor. 
 
 For further information write for free 
 illustrated circular of Mitchell's Models, 
 containing also valuable air-brake infor- 
 mation. 
 
 International Correspondence Schools 
 
 Box 1221, Scranton. Pennsylvania 
 
GRAPHITE 
 
 Dixon's Flake Graphite Lubricants 
 
 They're the standard for economical, positive 
 and efficient lubrication.:: 
 
 Dixon's Graphite Pipe-Joint Compound 
 
 For all threaded connections, insuring a tight fit 
 and a joint that can be taken apart without damage. 
 
 Dixon's Graphite Engine Front Finish 
 
 Its brilliancy is unaffected by the elements. 
 WRITE FOR LITERATURE ON THE ABOVE 
 
 JOSEPH DIXON CRUCIBLE COMPANY 
 
 * JERSEY CITY, N. J. 
 
 THE 
 
 Traveling Engineers Association 
 
 At their annual meetings each year since 1893 
 have had carefully prepared Committee Reports 
 on a great number of practical questions concern- 
 ing the operation of the locomotive and its var- 
 ious attachments like the lubricator, injector, and 
 air brake, as well as the proper handling of trains. 
 The Committee Reports, together with the discus- 
 sion thereon by the members of the Association, 
 are printed for distribution to others who wish to 
 inform themselves on these important topics. 
 Copies of these Reports are on sale at the office 
 of the secretary. Price 50 cents for paper bound; 
 $1 for leather covers. Reports for the meetings 
 previous to 1900 are all gone. Address, 
 
 W. 0. THOMPSON, Secretary, 
 
 N. Y. C. Car Shops 
 
 EAST BUFFALO, N. Y. 
 
Chicago Locomotive Lubricator 
 
 Class "C" 
 3-Fceds with Solid Sight Feed Glasses 
 
 To Operate 
 
 Open steam valve full at boiler. Open valve 62 one 
 turn. Open water valve 73 three turns. Note the feed 
 glasses to see if filled with water. After the glasses are 
 filled with water regulate feed with valve-31. 
 
 The auxiliary oil cup 65, close pressure valve 62. 
 See that valve 78 is closed. Open auxiliary drain valve 
 88 to free cup of water. Open auxiliary filler plug 66 
 and fill. After cup is filled, open feed valve 78 wide. 
 This auxiliary cup can be operated with •team on lubri- 
 cator and engine throttle open. 
 
 Write us for full descriptive pamphlets. 
 
 The Ohio Injector Co. 
 
 1437 Monadnock Block, Chicago, 111. 
 
Star Brass Manufacturing Go. 
 
 Air Brake (JwsMfr i 9 \ % m 
 Inspectors' ^wm^^*i^ 
 
 Gauges. ^^5§i 
 
 The above illustration represents a very useful article 
 that we have recently produced for the assistance of the 
 Air Brake Inspector to instantly determine the pressure or 
 test the signal apparatus by attaching to the hose couplings of 
 the rear coach, as it will fit either the brake or signal coup- 
 lings. These features obviate the necessity of the inspector 
 consulting the air gauge in the cab, and the great advantage 
 that this very useful instrument affords will readily be seen. 
 The Test Gauge is only 2£ in. in diameter and weighs less than 
 one pound. They are exclusively made by us and prices will 
 be forwarded upon application. 
 
 Also original and exclusive manufacturers of 
 
 Westinghouse Duplex Air and Locomotive Gauges 
 
 Fitted with our Patent Non-Corrosive Movement and 
 
 Non-Setting corrugated Spring tubes 
 
 Open and Muffled Locomotive Pop Safety Valves. 
 
 Extra Heavy Water Gauges, Gauge Cocks, Lubricators, Etc. 
 
 MAIN OFFICE AND WORKS 
 
 104-14 E. Dedham St. Boston, Mass. 
 
 BRANCHES 
 421 Fulton Building, 70 Cortland St.. 
 
 Pittsburgh, Pa. New YorK City 
 
 404 St. James St.. 
 
 Montreal. Canada 
 
Railroad Men's Catechism 
 
 By Angus Sinclair Company 
 
 Contains complete examination course for Engineers and 
 Firemen. One of the most useful helps ever offered to Rail- 
 way riien. Numerous illustrations, 200 pages,, flexible cloth. 
 PRICE $1.00 
 
 Locomotive Engine Running and 
 Management 
 
 By Angus Sinclair 
 
 A book that has probably helped more enginemen than any 
 other. Practical, reliable and brought up-to-date. Twenty- 
 first edition ready. PRICE $2.00 
 
 Twentieth Century Locomotives 
 
 By Angus Sinclair Company 
 
 It has 670 pages dealing with the designing, construction, re- 
 pairing and operating of modern locomotives. Work shop 
 operations, care and management of engines. Quick repairs 
 on the road, shop tools, shop recipes, train resistance and 
 power calculations, definitions and tables. Standard types of 
 engines illustrated and described. Fully indexed. Most all 
 round useful modern compendium of the locomotive. 
 PRICE $2.00 
 
 In addition to the above every railroad man should peruse 
 
 Railway and Locomotive Engineering 
 
 A high class illustrated monthly periodical universally ac- 
 knowledged to be the most interesting and the best illus- 
 trated railway paper published. Keeps abreast of the latest 
 improvements. Constantly describing and illustrating 
 
 New Appliances New Methods New Features 
 
 Sample Copies on Application 
 
 TWO DOLLARS PER ANNUM 
 
 Published by the 
 
 Angus Sinclair Company 
 
 114 Liberty Street New York 
 
BRAKEMAN'S 
 AIR BRAKE AND SIGNAL COCK 
 
 For Controlling From Rear of Trains When Backing 
 
 THE methods of handling trains at terminals and passen- 
 ger yards have entirely changed within a few years and 
 it is now a universal practice that trains be backed into the 
 station and from there to the yards. This makes it necessary 
 to have them positively controlled from the rear end. It is 
 
 also necessary to have a substi- 
 tute for the engine bell, as a 
 warning in passing into stations 
 and yards. 
 
 The cut shows a device which 
 is designed to fulfill these re- 
 quirements. It is a combined 
 plug-cock and alarm whistle (A) 
 attached by a short length of 
 hose or pipe to the train "pipe" 
 of the rear car. The whistle is 
 blown by pressing the button (B) 
 shown in the cut, which allows 
 air to pass through the hollow 
 handle of the cock to whistle, 
 which is shown on the end of 
 the handle, blowing the same 
 and giving the necessary alarm. 
 The air used for this pur* 
 pose, on account of the 
 design of the whistle valve, 
 POSITIVELY does not 
 affect the brake system. 
 By moving the handle of the 
 cock in either direction exhaust 
 is made from the train pipe, 
 through opening C, the brake 
 set, and consequent positive con- 
 trol of the train given. 
 "The device is also valuable in switching of height trains, 
 especially during the night or in thick weather, as the train 
 by its use is under complete control from both ends. 
 
 SHERBURNE & CO., 
 
 Sole Manufactures 
 
 53 Oliver Street, BOSTON, MASS., U. 
 
 S. A. 
 
The American 
 Automatic Slack Adjuster 
 
 MANUFACTURED BY THE 
 
 AMERICAN BRAKE COMPANY 
 
 St Louis, Mo., U. S. A 
 
SAVE 
 
 LIVES 
 
 MONEY 
 
 Collisions 
 
 CHEAPER 
 
 AND than 
 
 More Reliable 
 
 OIL 
 
Sellers Non-Lifting Injector of 1908 
 
 Has all of the advantages and none of the 
 disadvantages of the Lifting Injector 
 
 RE-STARTING SELF ADJUSTING 
 
 When the steam valve is opened, water is admitted 
 
 automatically. When the steam valve is closed, 
 
 lazy cock closes automatically. 
 
 WM. SELLERS ft CO., Incp. Philadelphia, Pa. 
 
MAR 10 1910 
 
 Deacidified using the Bookkeeper process. 
 Neutralizing agent: Magnesium Oxide 
 Treatment Date: April 2004 
 
 PreservationTechnologies 
 
 A WORLD LEADER IN PAPER PRESERVATION 
 
 1 1 1 Thomson Park Drive 
 Cranberry Township, PA 16066 
 (724)779-2111 
 
One copy del. to Cat. Div. 
 
 i'W-