■•^^ Class _JIIi:j= Rnnk .Kfe COPYRIGHT DEPOSIT. T The Science of Railways For the convenience of those interested particularly in certain lines of. work, Kirkman's "Science of Railways" is divided and sold in groups, as follows : The price of these groups, and for the complete set, are spe- cially made to railway employes, and payment may be made on the monthly installment plan if desired. The books are bound in half leather, and are a handsome addition to any library. Group F, LOCOMOTIVE SHOPS, 4 Vols., 2 Portfolios, Price, $2O.0O- Locomotive and Motive Power Depart ment. Engineers' and Firemen's Handbook. Locomotive Appliances. Electricity Applied to Railways. Air Brake — Construction and Working. Operating Trains. Portfolio of Locomotives. Portfolio of Air Brake. Group B, AGENTS AND OPERATORS, 5 Volumes, 3 Portfolios, Price, $35.00. Passenger Traffic and Accnmts. Freight Traffic and Accounts. Collection of Revenue. Electricity Applied to Railways. Operating Trains. Portfolio of Locomotives. Portfolio of Air Brake. Group C, OFFICES AND STATIONS. 9 Vols., S Portfolios, Price, $32.00. Organization of Railways — Financing. Passenger Traflic and Accounts. Freight Traffic and Accounts. Safeguarding Railway Expenditures. Oeneral Accounts and Cash. Collection of Revenue. Railway Rates and Government Owner- ship. Electricity Applied to Railways. Operating Trains. " Poitfolio of Locomotives. Portfolio of Air Brake. Group D, ROADWAY AND TRACK. 3 Vols., 1 Portfolio, Price, $10.00. Building nnd Renairing Railways. Safeguarding Railway Expenditures. Portfolio of Locomotives. Group E, CAR SHOPS. 2 Vols., 3 Port- folios, Price, $15.00. Cars — Construction, Handling and Su- pervision. Air Brake — Construction and Working. Portfolio of Cars. Portfolio of Air Brake. Locomotive Appliances. Shops and Shop Practice. Vol. I. Shops and Shop Practice, Vol. II. Air Brake — Construction and Working. Portfolio of Locomotives. Portfolio of Air Brake. Group G, ROUNDHOUSE, 3 Vols., 3 Portfolios, Price, $15.0O. Shops and Shop Practice, Vol. I. Shops and Shop Practice, VoL II. Portfolio of Locomotives. Portfolio of Air Brake. Group H, TRAIN MEN, 3 Vols., 3 Port- folios, Price, $18.00. Operating Trains. Cars — Construction, Handling and Su- pervision. Air Brake — Construction and Working. Portfolio of Cars. Portfolio of Air Brake. Group I. Full Set 17 Vols., 3 Port- folios, Price, $45.00. Locomotive and Motive Power Depart- ment. Engineers' and Firemen's Handbook. Locomotive Appliances. Electricity Applied to Rfihv;^ys. Cars — Construction, Handling and Su- pervision. Air Brake — Construction and Working. Operating Trains. Collection of Revenue. Building and Repairing Railways. Organization of Railways — Financing. Passenger Traffic and Accounts. Freight Traffic and Accounts. Safeguarding Railway Expenditures. General Accounts and Cash. Railway Rates and Government Ownei'c ship. Shops and Shop Practice, Vol. I. Shops and Shop Practice, Vol. II. Portfolio of Locomotives. Portfolio of Cars. Portfolio of Air Brake. Full information furnished on request. CROPLEY PHILLIPS COMPANY, Publishers TRIBUNE BUILDING CHICAGO %- SUPPLEMENT TO THE VOLUME AIR BRAKE ,^ THE SCIENCE OF RAILWAYS MARSHALL M. KIRKMAN EMBODYING DESCRIPTIONS AND INSTRUCTIONS FOR THE MANIPULATION OF THE WESTINGHOUSE No. 6 "E T" ENGINE AND TENDER BRAKE EQUIPMENT, TOGETHER WITH QUESTIONS AND ANSWERS RELA- TIVE TO THE PRACTICAL OPERATION THEREOF: THE NEW YORK B-3 LOCOMOTIVE BRAKE EQUIPMENT; NEW YORK DUPLEX AIR PUMPS AND PUMP GOVERNORS: AND THE DUKESMITH E. C. EQUIPMENT No. 6 AND CAR CONTROL VALVE CHICAGO CROPLEY PHILLIPS COMPANY 1911 v^ Copyright by CROPLEY PHILLIPS. COMPANY 1911 All riulits reserved ©CLA'^97'747'^ Yu ^ k THE NO. 6 "E. T." LOCOMOTIVE BRAKE EQUIPMENT. ^.KE led in The I, is a ts by rative arable anipu- on the lie re- brake- t. t, giv- equip- )ns of ption: he air en the servoir •m the valves, motive motive ' inde- ng-res- brake- THE NO. 6 "E. T." LOCOMOTIVE BRAKE EQUIPMENT. The ' * E. T. " Locomotive Brake equipment was introduced in 1905 and is now known as the ' ' No. 5 " E. T. Equipment. The "No. 6" E. T. Equipment, illustrated and described herein, is a modification of the No. 5, to accomplish the same results by- simpler means, as Avell as to embody certain additional operative advantages which railroad men suggested as valuable and desirable in a locomotive brake apparatus. The only difference in manipu- lation between No. 5 and No. 6 " E. T. " equipment is that on the second engine in double heading, the No. 6 brake-valve handle re- mains in running position, as with the old standard G-6 brake- valve, instead of in lap position, as with the No. 5 equipment. AEEANGEMENT OF APPAEATUS. Fig. 1-A is a diagram of the No. 6 * ' E. T. " equipment, giv- ing the necessary instructions for correctly piping up the equip- ment; Fig. 1-B is a similar diagram giving the designations of apparatus and piping as referred to in the following description: PAETS OF THE EQUIPMENT. 1. The Air Pump to compress the air. 2. The Main Eeservoiks, in which to store and cool the air and collect water and dirt. 3. A Duplex Pump Governor to control the pump when the pressures are attained for which it is regulated. 4. A Distributing Valve, and small double-chamber reservoir to which it is attached, placed on the locomotive to perform the functions of triple valves, auxiliary reservoirs, double check valves, high-speed reducing valves, etc. 5. Two Brake Valves, the Automatic to operate locomotive and train brakes, and the Independent to operate locomotive brakes only. 6. A Feed Valve to regulate the brake-pipe pressure. 7. A Eeducing Valve to reduce the pressure for the inde- pendent brake valve and for the air-signal system when used. 8. Two Duplex Air Gauges; one, to indicate equalizing-res- ervoir and main-reservoir pressures; the other, to indicate brake- pipe and locomotive brake-cylinder pressures. 5 THE AIB BRAKE. il'f NO. 6 "E. T." EQUIPMENT. 7 9. Driver, Tender, and Truck-Brake Cylinders, Cut-Out Cocks, Air Strainers, Hose Couplings, Fittings, etc., incidental to the piping, for purposes readily understood. NAMES OF PIPING (Kefer to Fig. 1-B). D— Discharge Pipe: Connects the Air Pump to the first Main Reservoir. C — Connecting Pipe: Connects the two Main Eeservoirs. ME — Main-Reservoir Pipe: Connects the second main reser- voir to the Automatic Brake Valve, Distributing Valve, Feed Valve, Reducing Valve, and Pump Governor. FV — Feed-Valve Pipe : Connects the Feed Valve to the Auto- matic Brake Valve. E — Excess-Pressure Governor Pipe: Connects the Feed- Valve Pipe to the Excess-Pressure Head of the Pump Governor. EV — Reducing-Valve Pipe: Connects the Reducing Valve to the Independent Brake Valve, and to the Signal System, when used. BP — Brake Pipe: Connects the Automatic Brake Valve with the Distributing Valve and all Triple Valves on the cars in the train. BC — Brake- Cylinder Pipe: Connects the Distributing Valve with the Driver, Tender and Truck-Brake Cylinders. H — Application-Cylinder Pipe: Connects the Application Cylinder of the Distributing Valve to the Independent and Auto- matic Brake Valves. I — Distributing-Valve Release Pipe: Connects the Applica- tion Cylinder exhaust port of the Distributing Valve to the Auto- matic Brake Valve through the Independent Brake Valve Referring to Fig. 1-B, air compressed by the pump passes through pipes D and C as usual to the main reservoirs and the main-reservoir pipe, MR. The main-reservoir cut-out cock, W, is to cut off and vent the air from the main-reservoir pipe, when removing any of the apparatus except the governor. The end to- ward the main reservoir is tapped for a pipe connection, G, to the Pump Governor. Before this cock is closed the double-heading cock, X, should be closed, and the brake-valve handle placed in release position. This is to prevent the slide valve of the feed valve, and the rotary valve of the brake valve, being lifted from their seats. Beyond the main-reservoir cut-out cock, the main-reservoir pipe has four branches, one of which runs to the automatic brake valve, one to the feed valve, one to the reducing valve, and one to the dis- tributing valve. As a result, the automatic brake valve receives air from the main reservoirs in two ways, one direct and the other through the Feed Valve, The Feed- Valve Pipe, FV, from the feed valve to the automatic TRE AIE BRAKE. NO. 6 ''E. T." EQUIPMENT 9 brake valve has a branch, EG, to the top of the excess-pressure head of the duplex pump governor. The third branch of the main-reservoir pipe connects with the reducing valve. Air at the pressure for which this valve is set (45 pounds) is supplied to the independent brake valve through the reducing-valve pipe EV. When the air-signal system is installed, it is connected to the reducing-valve pipe, in which case the re- ducing valve also takes the place of the signal reducing valve formerly employed. In the branch pipe supplying the air-signal system is placed a combined strainer, check-valve, and choke fitting, Y. The strainer prevents any dirt from reaching the check valve and choke fitting. The check valve prevents air from flowing back from the signal pipe when the independent brake is applied. The choke fitting prevents the reducing valve from rais- ing the signal-pipe pressure so quickly as to destroy the operation of the signal. Large Duplex Air Gauge Small Duplex Air Gauge (No. 1). (No 2). The distributing valve has five pipe connections, made through the end of the double-chamber reservoir, three on the left and two on the right. Of the three on the left, the upper, ME, is the sup- ply from the main reservoir; the intermediate, H, is the applica- tion-cylinder pipe, leading to the independent and automatic brake valves; and the lower, I, is the distributing-valve release pipe, leading through the independent brake valve, when the handle is in running position, to the automatic brake valve. Of the two on the right, the lower, BP, is the brake-pipe-branch connection, and the upper, BC, is the brake-cylinder pipe, branching to all brake cylinders on the engine and tender. In this pipe are placed cocks for cutting out the brake cylinders when necessary, and in the en- gine truck and tender brake-cylinder cut-out cocks are placed choke fittings to prevent serious loss of main-reservoir air and the release 10 TEE AIE BEAKE. of the other locomotive brakes during a stop, in ease of burst brake-cylinder hose. The two Duplex Air Gauges are connected as follows: Gauge No. 1; Red Hand, to main-reservoir pipe under the automatic brake valve; Black Hand, to gauge-pipe tee of the automatic brake valve. Gauge No. 2 ; Eed Hand, to the brake-cylinder pipe ; Black Hand, to the brake pipe below the double-heading .cock. The amount of reduction made during an automatic applica- tion is indicated by the black hand of Gauge No. 1. The black hand of , Gauge 2 is to show the brake-pipe pressure when the en- gine is second in double heading, or a helper. The automatic-brake-valve connections, other than already men- tioned, are the brake-pipe, the main-reservoir, the equalizing , reser- voir, and the lower connection to the excess-pressure head of the pump governor. PEINCIPLES OF OPERATION. Before taking up the description of each part of this equip- ment, we wish to emphasize that the principles governing the oper- ation of it are just the same as those of pre\dous automatic air brake equipments. The difference consists in the means for sup- plying the air pressure to the brake cylinders. Instead of a triple valve and auxiliary reservoir for each of the engine and tender equipments, the distributing valve is made to supply all brake cylinders. The distributing valve consists of two portions called the ' ' equalizing portion ' ' and ' ' application portion. " It is con- nected to a ' ' double-chamber reservoir, ' ' the two chambers of which are called respectively the ' ' pressure chamber ' ' and the ' ' application chamber. ' ' The latter is ordinarily connected to the application portion of the distributing valve in such a way as to enlarge the volume of that part of it called the ' ' application cylinder" (Fig. 2). The connections between these parts as well as their operation, may be compared with that of a miniature brake set — the equalizing portion representing the dummy triple valve; the pressure chamber, the dummy auxiliary reservoir; and the application portion (dummy cylinders) always having prac- tically the same pressure in its cylinder as that in the real brake cylinders. This is shown by the diagrammatic illustration in Fig. 2. For convenience, compactness and security they are combined in one device as shown in Figs. 3, 4 and 5. The equalizing portion (dummy triple) and pressure chamber (dummy auxiliary) are used in automatic applications only; reductions of brake-pipe pressure cause the equalizing valve to connect the pressure cham- ber dummy auxiliary to the dummy cylinder, allowing air to flow from the former to the latter. The upper slide valve connected to the piston rod of the application portion, admits air to the brake cylinders and is called the ' ' application valve, ' ' while the lower one releases the air from the brake cylinders and is called NO. 6 ''E. T." EQUIPMENT. 11 TO INDEPENDENT BHAKE VALVE. DUMMY CYL. CHAMBER \\ \ \\\\\\\\\\\\\Y PRESSURE CHAMBER. DUMMY AUXILLIARY Fig. 2. Diagrammatic View of the Essential Parts of the Distributing Valve, and Double-Chamber Eeservoir. 12 THE AIR BRAKE. the ' ' exhaust valve. ' ' As the air admitted to the brake cylinders comes directly from the main reservoirs, the supply is practically unlimited. Any pressure m tne dummy cylinder will force the ap- plication piston to close the exhaust valve, open the application valve and admit air from the main-reservoirs to the locomotive brake cylinders until their pressure equals that in the dummy cyl- inder; any variation of this (dummy) cylinder pressure will be exactly duplicated in the locomotive brake cylinders, and the re- sulting pressure maintained regardless of any brake-cylinder leak- age. The whole operation of this locomotive brake, therefore, consists in admittng and releasing air pressure into or out of the dummy cylinder, in independent applications directly through the independent brake valve; in automatic applications, by means of the equalizing (dummy triple valve) portion and the air pressure stored in the pressure chamber (dummy auxiliary). The well known principle embodied in the quick-action triple valve, by which it gives a high braking power in emergency appli- cations, and a sufficiently low^er one in full service applications, to provide a desired protection against wheel sliding, is embodied in the No. 6 distributing valve. This is accomplished by cutting off the application chamber from the application cylinder in all emer- gency applications. In such applications, the pressure chamber has to fill the small volume of the application cylinder only, thus giving a high equalization, and a correspondingly high brake- cylinder pressure. In service applications, it must fill the same volume combined with that of the application chamber, thus giv- ing a lower equalization and correspondingly lower brake-cylinder pressure. The following description gives the operation in detail. THE NO. 6 DISTRIBUTING VALVE. This valve is the important feature of the *'E. T." equip- ment. Fig. 3 shows photographic views of the valve and its double-chamber reservoir. The pipe connections, as previously referred to, are plainly shown. Fig, 4 shows the two chambers of the reservoir. The safety valve, 34, is an essential part of the distributing valve, and is described under the heading * ' E-6 Safety Valve. ' ' Referring to Figs. 4 and 5, the names of parts of this appa- ratus are as follows: 2, Body; 3, Application-Valve Cover; 4, Cover Screw; 5, Application Valve; 6, Application-Valve Spring; 7, Application-Cylinder Cover; 8, Cylinder-Cover Bolt and Nut; 9, Cylinder-Cover Gasket; 10, Application Piston; 11, Piston Fol- loM-er; 12, Packing-Leather Expander; 13, Packing Leather; 14, Application-Piston Nut; 15, Application-Piston Packing Ring; 16, Exhaust Valve; 17, Exhaust-Valve Spring; 18, Application-Valve Pin ; 19, Application-Piston Graduating Stem ; 20, Application- Piston Graduating Spring; 21, Graduating-Stem Nut; 22, Upper NO. 6 "E. T." EQUIPMENT. IS Fig. 3. No. 6 Distributing Valve and Double Chamber Eeservoir. Connections: ME^-Main-Eeservoir Pipe; 4 — D istributing-Valve Eelease Pipe; 2 — Application-Cyl- inder Pipe; CYLS— Brake-Cylinder Pipe; BP— Br ake Pipe. u TEE AIB BBAEE. NO. 6 "E. 1\" EQUIPMENT. 15 J^^r~i V-CFESi 3J> Fig. 5. No. 6 Distributing Valve. Connections: ME — Main-Eeservoir Pipe; IV— Distributing- Valve Eelease Pipe; II — Application-Cylinder Pipe; CYLS — Brake- Cylinder Pipe; BP — Brake Pipe. 16 TEE AIE BEAKE. Cap Nut; 23, Equalizing-Cylinder Cap; 24, Cylinder-Cap Bolt and Nut; 25, Cylinder-Cap Gasket; 26, Equalizing Piston; 27, Equaliz- ing-Piston Packing King; 28, Graduating Valve; 29, Graduating- Valve Spring; 31, Equalizing Valve; 32, Equalizing-Valve Spring; 33, Lower Cap Nut; 34, Safety Valve; 35, Double-Chamber Eeser- voir; 36, Eeservoir Stud and Nut; 37, Keservoir Drain Plug; 38, Distributing-Valve Drain Cock; 39, Application-Valve-Cover Gas- ket; 40, Application-Piston Cotter; 41, Distributing-Valve Gasket (not shown); 42, Oil Plug; 43, Safety -Valve Air Strainer; 44, Equaiizing-Piston Graduating Sleeve; 45, Equalizing-Piston Grad- uating-Spring Nut; 46, Equalizing-Piston Graduating Spring. To simplify the tracing of the ports and connections, the vari- ous positions of this valve are illustrated in nine diagrammatic views; that is, the valve is distorted to show the parts differently than actually constructed with the object of explaining the opera- tion clearly instead of showing exactly how tney are designed. The chambers of the reservoir are for convenience indicated at the bottom as a portion of the valve itself. In Pig. 5, equalizing piston 26, graduating valve 28, and equalizing slide valve 31, are shown as actually constructed. But as there are ports in the valves which cannot thus be clearly indicated, the diagrammatic illustrations show each slide valve considerably elongated so as to make all the ports appear in one plane, with similar treatment of the equalizing-valve seat. Fig. 6 shows the correct location of these ports. Keferring to Fig. 7 it will be seen that main-reservoir pressure is always present in the chamber surrounding application valve 5 by its connection through passage a, a, to the main-reservoir pipe. Chamber h to the right of application piston 10 are always in free communication with the brake cylinders, through passage c and the brake-cylinder pij)e. Application cylinder g at the left of ap- plication piston 10 is connected by passage Ji with the equalizing valve seat, and to the brake valves through the application-cylin- der pipe. AUTOMATIC OPEEATION. Charging. Eeferring to Fig. 7, which shows the movable parts of the valve in the release position, it Avill be seen that as cham- ber p is connected to the brake pipe, brake-pipe air flows through the feed groove v around the top of piston 26 into the chamber above equalizing valve 31, and through port o to the pressure chamber, until the i^ressures on both sides of the piston are equal. Service. "When a service application is made with the auto- matic brake valve, the brake-pipe pressure in chamber p is re- duced, causing a difference in pressure on the two sides of this piston, which results in the piston moving toward the right. The first movement of the piston closes the feed groove, and at the same time moves the graduating valve until it uncovers the upper NO. 6 "E. T/' EQUIPMENT. 17 PLAN OF GRADUATING VALVE. FACE OF SLIDE VALVE. ^9 Zj PLAN OF SLIDE VALVE. 0-- A-0 (K FLAN OF SLIDE \ffK\JJE. SEAT. Fig. 6. Graduating Valve, Equalizing Valve, and Equalizing Valve Seat of No. 6 Distributing Valve. 18 TEE AIB BEAKE. MR Fig. 7. Release, Automatic or Independent. Connections: ME— Main-Reservoir Pipe; IV— Distributing- Yalve Re ease Pipe; II— Application-Cylinder Pipe; CYLS—Brake- Cylinder Pipe; BP— Brake Pipe. NO. 'E. T.*' EQUIPMENT. 19 < m SAFETY VALVE. THE AIE BRAKE. end of port b m the equalizing valve 31. As the piston continues Its movement the shoulder on the end of its stem engages the equalizing valve, which is then also moved to the right^untll the piston strikes, equalizing-piston graduating sleeve U, graduating spring 46 preventing further movement; port . in de^^TZl valve then registers with port h in the seat, and cavitv n in thf equalizing valve connects ports h and w in the seat. As" the equal' izmg-valve chamber is always in communication with the pressure chamber, air can now flow from the latter to both the appSon cylinder and application chamber. This pressure forcLCpliea tion piston 10 to the right, as shown in Fig. 8, causing exhaust valve 16 to close exhaust ports . and d, and^to compres? appS fb^'its'cor'r''"^-.?^^ ''' -^«° ----g appLatln valve 5, by Its connection with the piston stem through pin 18, to open Its port and allow air from the main-reservoirs to flow into cham bers &, & and through passage c to the brake cylinder^ v^l.S""'''^ ^^f movement just described, cavity t in the 'graduating valve connects ports r and s in the equalizing valve, and by thf same movement ports r and . are brought into^egist^r with por ! A and Z m the seat, thus establishing a communication from the application cylinder to the safety-valve, which bein^ set at 68 pounds, Imits the brake-cylinder pressure to this amount which is 3 pounds above the maximum obtained in emergency app icTtion from original 70 pounds. ^ *^ ^ippiicanon fn.^o^^ amount of pressure resulting in the application cylinder for a certain brake-pipe service reduction, depends on the com- parative volumes of the pressure chamber, application cylinder Td Its chamber. These volumes are such that with 70 pounds in the pressure chamber and nothing in the application ^cX^^^^^^ chamber, if they are allowed to equalize, for an example as .Sh llZceLlT (v?: ^t''*^-' «-^ -11 «how about'^SO pounds ^ervice Lap. When the brake-pipe reduction is not sufficient contZe untn fr""' ^^P^^^^^^^^' '^^ — litions described above continue until the pressure m the pressure chamber is reduced enough below that in the brake pipe to cause piston 26 to force graduating valve 28 to the left until stopped by the shoulder on 31 ZZJr""^ striking the right-hand end of^qualizing vaC 31, the position indicated m Fig. 9, and shown as Service Lap In this position, graduating valve 28 has closed port , so that no more air can flow from the pressure chamber to the appHcation cylinder and chamber. It also has closed port ., cutting off com munication to the safety valve, so that any possible leak in the la^ llLr^^^'r^'' ''' aPPlieation-cylinder^^ressure, and thus sm." ilarly affect the pressure in the brake cyliiders. The flow of aTr past application valve 5 to the brake cylinders continues unUl when Z"T: ''^^'*'^ '^''f' *^^* i^ *^^ application cylinder WfW% ^^ '' -Pf''"? ^^^ application-piston graduating spring qTwI r-P''*°" ?l*^ *^^ 1^^* *« ^^^ position shownVrTg! 9, thereby closing port &. Further movement is prevented by the NO. 6 "E. T." EQUIPMENT. 21 MR Pig, 8, Automatic Service. 22 TEE AIE BRAKE. > C O > o (/) m < o m "D O 0) H o z SAFETY VAUE, NO. 6 "E. T." EQUIPMENT. 23 resistance of exhaust valve 16, and the application-piston grad- uating spring having expanded to its normal position. The brake- cylinder pressure is then practically the same as that in the appli- cation cylinder and chamber. From the above description it will be seen that application pis- ton 10 has application-cylinder j^ressure on one side and brake- cylinder pressure on the other. When either pressure varies, the l)iston will move toward the lower. Consequently if that in cham- ber b is reduced, by brake-cylinder leakage, the pressure main- tained in the application cylinder will force piston 10 to the right, opening application valve 5 and again admitting air from the main-reservoirs to the brake cylinders until the pressure in cham- ber h is again slightly above that in the application cylinder when the piston again moves back to lap position. In this way the brake-cylinder pressure is always maintained equal with that in the application cylinder. This is the pressure-maintaining feat- ure. Automatic Belease. When the automatic brake valve is placed in release- position, and the brake-pipe pressure in chamber p is thereby increased above that in the pressure chamber, equalizing piston 26 moves to the left, carrying with it equalizing valve 31 and graduating valve 28 to the position shown in Fig. 7. The feed grcve v now being open permits the pressure in the pressure chamber to feed up until it is equal with that in the brake i-'ipe as before described. This action does not release the locomotive brakes because it does not discharge application-cylinder pressure. The release pipe is closed by the rotary valve of the automatic brake valve, and the application-cylinder pipe is closed by the rotary valves of both brake valves. To release the locomotive brakes, the automatic brake valve must be moved to running posi- tion. The release pipe is then connected by the rotary valve to the atmosphere, and as exhaust cavity fc in the equalizing valve 31 connects ports i, lu and li in the valve seat, application-cylin- der and chamber pressure will escape. As this pressure reduces, tlie brake-cylinder pressure will force application piston 10 to the left until exhaust valve 16 uncovers exhaust ports d and e, allowing brake-cylinder pressure to escape (J?ee Fig. 7), or in case of graduated release, to reduce in like amount to the reduc- tion in the apjDlication-cylinder pressure. Emcrtjency. When a sudden and heavy brake-pipe reduction is made, as in an emergency application, the air in the pressure chamber forces equalizing piston 26 to the right w^ith sufficient force to compress equalizing-piston graduating spring 46, so that the piston moves until it strikes against the leather gasket beneath cap 23 as shown in Fig. 10. This movement causes equalizing valve 31 to uncover port h in the bush without opening port w, making a direct opening from the pressure chamber to the application cylinder only, so that they c[uickly become equal- 24 TEE AIE BRAKE. MF» NO. 6 ''E. T." EQUIPMENT. 25 > H O 2 SAFETY VALVE. 26 TBE AIE BBAKE. ized. This cylinder volume, being small, and connected with that of the pressure chamber at 70-pounds pressure, equalizes at about 65 pounds. Also in this position of the automatic brake valve, a small port in the rotary valve allows air from the main- reservoirs to feed into the application-cylinder pipe, and thus to the application cylinder. The application cylinder is now con- nected to the safety valve through port Ji in the seat, cavity q and port r in the equalizing valve, and port b in the seat. Cavity q and port r in the equalizing valve are connected by a small port, the size of which permits the air in the application cylinder to escape through the safety valve at the same rate that the air from the main-reservoirs, feeding through the rotary valve of t'. ? automatic brake valve, can supply it, preventing the pressura from rising above the adjustment of the safety valve. In High-Speed Brake Service, the feed valve is regulated for 110-pounds brake-pipe pressure instead of 70, and main-reservoir pressure is 130 or 140 pounds. Under these conditions r.n emergency application raises the application-cylinder pressure to about 93 pounds, but the passage between cavity q and port r is so small that the flow of application-cylinder pressure to th? safety valve is just enough greater than the supply through the brake valve, to decrease that pressure in practically the same time and manner as is done by the high-speed reducing valve, until it is approximately 75 pounds. The reason why the pres- sure in the application cylinder, pressure chamber and brake cylinders does not fall to 68 pounds, to which pressure the safety- valve is adjusted, is because the inflow of air through the brake valve with the high main-reservoir pressure used in high-speed service is equal, at 75 pounds, to the outflow through the small opening to the safety valve. This is done to get a shorter stop in emergency. The application portion of the distributing valve • operates similarly, but more quickly than in service application. Emergency Lap. The movable parts of the valve remain in the position shown in Fig. 10 until the brake-cylinder pressure slightly exceeds the application-cylinder pressure, when the appli- cation piston and application valve move back to the position known as Emergency Lap as shown in Fig. 11. The release after an emergency is brought about by the same manipulation of the automatic brake valve as that following service application, but the effect on the distributing valve is somewhat different. When the equalizing piston, valve, and graduating valve are forced to the release position by the increased brake-pipe pressure in chamber p, the application chamber, with no pressure in, is connected to the application cylinder, with the emergency pressure in, through port w, cavity Tc, and port Ji. The pressure in the application cylinder at once expands into the application chamber until these pressures are equal, which results in the release of brake-cylinder pressure until it is slightly less than that in application cylinder and NO. 6 "E. T." EQUIPMENT. 27 MR Fig. 10. Emergency. TEE AIE BBAKE, ni 33 O m z o -< "0 O D "D O (fi H O z SAFETY VALVE. NO. 6 "E. T." EQUIPMENT. 31 chamber. Consequently, in releasing after an emergency, the brake-cylinder pressure will automatically reduce to about 15 pounds, which Avill remain until the automatic-brake-valve handle is moved to running position. If the brakes are applied by a conductor's valve, a burst hose, or parting of train, the movement of equalizing valve 31 breaks the connection between ports h and i through cavity k, so that the brakes will apply and remain applied until the brake-pipe pressure is restored. The handle of the automatic brake valve should be moved to lap position to prevent a loss of main- reservoir pressure. INDEPENDENT BEAKE OPEEATION. Independent Application. When the handle of the Inde- pendent Brake Valve is moved to either application position, air from the main reservoir, limited by the reducing valve to a maximum of 45 pounds, is allowed to flow to the application cylinder, forcing application piston 10 to the right as shown in Fig. 12. This movement causes application valve 5 to open its port and allow air from" the main-reservoirs to flow into cham- bers T), h and through passage c to the brake cylinders, as in an automatic application, until the pressure slightly exceeds that in the application-cylinder. The application-piston graduating spring and higher pressure then force application piston 10 to the left until application valve 5 closes its port. Further move- ment is prevented by the resistance of exhaust valve 16, and the application-piston graduating spring having expanded to its normal position, ^^i^is position, shown in Fig. 13, is known as Independent Lap. , - It will be seen that whatever pressure exists in the application cylinder will be maintained in the brake cylinders by the ' ' pres- sure maintaining ' ' feature already described under the heading ' ' Service Lap, ' ' and indicated in Fig. 9. Independent Release. When the handle of the independent brake valve is moved to release position, a direct opening is made from the application cylinder to the atmosphere. As the applica- tion-cylinder pressure escapes, brake-cylinder pressure in cham- bers h moves application piston 10 to the left, causing exhaust valve 16 to open exhaust ports e and d as shown in Fig. 7, thereby allowing brake-cylinder pressure to discharge to the atmosphere. If the independent brake valve is returned to lap before all of the application-cylinder pressure has escaped, the application piston 10 will return to independent lap position as soon as the brake-cylinder pressure is reduced a little below that remaining in the application cylinder, thus closing exhaust ports e and d, and holding the remaining pressure in the brake cylinders. In this way the independent release may be graduated as desired. 32 THE AIR BBAKE, Fig, 12, Independent Application, NO. 6 ''E. T." EQUIPMENT. 33 SAFETY VALVE 34 THE AIB BBAKE. This equipment has all the flexibility and ease of manipula- tion possessed by the combined automatic and straight air equip- ment, with much less apparatus and complication, besides the other important features of pressure maintaining, equal pressures in all brake cylinders, and the fact that it is always possible to release the locomotive brakes with the independent-brake valve, even when automatically applied. In connection with this last mentioned feature. Fig. 14 shows the position the distributing- valve parts will assume, if the locomotive brakes are released by the independent brake valve after an automatic application has been made. This results in the application portion going to release position without changing the conditions in either the pressure-chamber or brake pipe; consequently, the equalizing por- tion does not move until release is made by the automatic brake valve. An independent release of locomotive brakes may also bo made in the same manner, after an emergency application by the automatic brake valve. However, owing to the fact that, in this position, the automatic brake valve will be supj^lying the applica- tion cylinder through the. maintaining j^ort in the rotary valve, the handle of the independent brake valve must be held in release position to prevent the locomotive brakes from reapplying, so long as the handle of the automatic brake valve remains in emergency position. The equalizing portion of the distributing valve will remain in the position shown in Figs. 10 and 11, while the application portion will assume the position shown in Fig. 14. Double Heading. When there are tAvo or more locomotives in a train, the handles of both brake valves on each locomotive except the one from which the brakes are being operated, should be carried in running position. The release pipe is then open to the atmosphere at the automatic brake valve, and the operation of the distributing valve is the same as that described during automatic-brake applications. In double heading, therefore, the application and the release of the distributing valve on each helper locomotive is similar to that of the triple valves on the train. But in case an engineer on a helper finds it necessary to apply or to release his brakes independently of the train, he can do so by using the independent brake valve, without moving the handle of the automatic valve. Port u drains the application cylinder of any moisture pre- cipitated from the air in chambers h ; such moisture passes to the lower part of the distributing valve through port m, where it may be drawn off by drain cock 38. To remove piston 10 and slide valve 16, it is absolutely neces- sary to 'first remove cover 3, application valve 5 and valve pin 18. THE QUICK-ACTION CYLINDEE CAP. The equalizing portion of the distributing valve, as already NO. 6 ''E. T." EQUIPMENT. 35 MR Fig. 13, Independent Lap, 36 TEE AIE BRAKE. Z D m ■D m z o m 2 H r > "0 O H O Z SAFETY VALVE. NO. 6 "E. T.'' EQUIPMENT. 37 described, corresponds to the plain triple valve of the old standard locomotive brake equipments. There are, however, con- ditions under which it is advisable to have it correspond to a quick-action triple; that is, — vent brake-pipe air into the brake cylinders in an emergency application. To obtain this, the cylin- der cap 23, Fig. 5, is replaced by the * ' Quick- Action Cylinder Cap, ' ' illustrated in Fig. 15. In an emergency application, as equalizing piston 26 moves to the right and seals against the gasket (J^ig. 16) the knob on the piston strikes the graduating stem 50, causing it to compress equalizing-piston graduating spring 55, and move slide valve 48 to the right, opening port j. Brake-pipe pressure in chamber I) flows to chamber X, pushes down check valve 53, and passes to the brake cylinders through port m in the cap and distributing- valve body. When the brake cylinders and brake pipe equalize, check valve 53 is forced to its seat by spring 54, thus preventing air in the brake-cylinders from flowing back into the brake pipe. When a release of the brakes occurs and piston 26 is moved back to its normal position (Fig. 7), spring 55 forces graduating stem 50 and slide-valve 48 back to the position shown in Fig. 15. In all other respects, the operation of a distributing valve having this cap is exactly as described before. E-6 SAFETY VALVE. Fig. 17 is a sectional view of the safety valve which is an essential part of the distributing valve. It is unlike the ordinary safety valve, as its construction is such as to cause it to close quickly with a "pop" action, insuring its seating firmly. It is sensitive in operation and responds to slight differences of pressure. The names of the parts are 2, Body; 3, Cap Nut; 4, "Valve; 5, Valve Stem; 6, Adjusting Spring; 7, Adjusting Nut. Valve 4 is held to its seat by the compression of spring 6 between the stem and adjusting nut 7. When the pr'^ ure below valve 4 is greater than the force exerted by the spring, it rises, and as a larger area is then exposed, its movement upward is very quick, being guided by the brass bush in the body 2. Two ports are drilled in this bush upward to the spring chamber; and two outward through the body to the atmosphere, although only one of each of these is shown in the cut. As the valve moves upward, its lift is determined by the stem 5 striking cap nut 3. It closes the two vertical ports in the bush connecting the valve and spring chambers, and opens the lower ports to the atmosphere. As the air pressure beloW' valve 4 decreases, and the compression of the spring forces the stem and valve dowmAvard, the valve restricts the lower ports to the atmosphere and opens those between the valve and spring chambers. The discharge air pres- sure then has access to the spring chamber. This chamber is TEE AIB BBAEE, MR Fig. 14. Release Position. When Locomotive Brake is released by Independent Brake Valve After an Automatic Application. NO. 6 "E. T." EQUIPMENT. O PI "D m z o O aJ z SAFETY VALVE. TEE AIE BRAKE, fiG. 15. The Quick-Action Cylinder Cap foe No. 6 Distributing Valve. NO. 6 ''E. T." EQUIPMENT. 41 3AnVA Ai3dVS < O z o H o < o D Z o H (0 O Q. Ul (/) < U J Id 42 TEE AIB BEAEE. ^4Ri Fig. 16. Emergency Position of No. 6 Distributing Valve With Quick-Action Cap. NO. 6 *'E. T/' EQUIPMENT. 48 m m 7) o m z o < •D (/I H z Q c o 7s > O H z o > SAFETY VALVE. 44 TEE AIB BRAKE. always connected to the atmosphere by two small holes through the body, 2; the air from the valve chamber enters more rapidly than it can escape through these holes, causing pressure to accumulate above the valve and assist the spring to close it with the ' ' pop ' ' action before mentioned. The safety valve is adjusted by removing cap nut 3, and screwing up or down on adjusting nut 7. After the proper adjustment is made, cap nut 3 must be replaced and securely tightened, and the valve operated a few times. Particular atten tion must be given to see that the holes in the valve body are always open, and that they are not changed in size, especially the two upper holes. This safety valve should he adjusted for 68 'pounds. The safety valve, as are all adjustable devices, is more easily and accurately adjusted when done on a shop testing rack. THE H-6 AUTOMATIC BEAKE VALVE. This Brake Valve, although modelled to a considerable extent upon the principles of previous valves, is necessarily different in detail, since it not only performs all the functions of such types but also those absolutely necessary to obtain all the desirable operating features of the No. 6 Distributing Valve. ,rig. 18 is taken from a photograph of this brake valve, while Fig. 19 shows two views, the upper one being a plain view with section through the rotary-valve chamber, the rotary valve being removed; the lower one a vertical section. In these views the pipe connections are indicated. Fig. 20 shows two views of this valve similar to those of Fig. 19, with the addition of a plan or top view of the rotary valve. The six positions of the brake-valve handle are, beginning at the extreme left, Eelease, Eunning, Holding, Lap, Service, and Emer- gency. The names of the parts are as follows : 2, Bottom Case ; 3, Eotary- Valve Seat; 4, Top Case; 5, Pipe Bracket; 6, Eotary Valve; 7, Eotary- Valve Key; 8, Key Washer; 9, Handle; 10, Handle-Latch Spring; 11, Handle Latch; 12, Handle-Latch Screw; 13, Handle Nut; 14, Handle Lock Nut; 15, Equalizing Piston; 16, Equalizing-Piston Packing Eing; 17, Valve-Seat Upper Gasket; 18, Valve-Seat Lower Gasket; 19, Pipe-Bracket Gasket; 20, Small Union Nut; 21, Brake-Valve Tee; 22, Small Union Swivel; 23, Large Union Nut; 24, Large Union Swivel; 25, Bracket Stud; 26, Bracket-Stud Nut; 27, Bolt and Nut; 28, Cap Screw; 29, Oil Plug; 30, Eotary- Valve Spring; 31, Service-Exhaust Fitting. Eeferring to the rotary valve, a, j and s are ports extending directly through it, the latter connecting with a groove in the face; f and Z? are cavities in the valve face; o is the exhaust cav- ity; it; is a port in the face of the valve connecting by a corc.d passage with o; /^ is a port extending from the face over cavity Jc NO. 6 "E. T." EQUIPMENT. ^ Fig. 17. E-6 Safety Valve. 46 TRE Am BEAKE. I' Pig. 18, H-6 Automatic Brake Valve. NO. 6 "E. T." EQUIPMENT. 47 and connecting with exhaust cavity o; n is a groove in the face having a small port which connects through a cavity in the valve with cavity k. Eeferring to the ports in the rotary-valve seat, d leads to the feed-valve pipe; b and c lead to the brake pipe; g leads to chamber D; ex is the exhaust opening leading out at the back of the valve; e is the preliminary exhaust port leading to chamber D ; r is the warning port leading to the exhaust ; p is the port leading to the pump governor; I leads to the distributing- valve release pipe; u leads to the application-cylinder pipe. In describing the operation of the brake valve, it will be more readily understood if the positions are taken up in the order in which they are most generally used, rather than their regular order as mentioned previously. Charging and Release Position. The purpose of this position is to provide a large and direct passage from the main reservoir to the brake pipe, to permit a rapid flow of air into the latter to (a) charge the train brake system; (b) quickly release and recharge the brakes; but (c) not release locomotive brakes, if they are applied. Air at main-reservoir pressure flows through port a in the rotary valve and port & in the valve seat to the brake pipe. At the same time, port j in the rotary valve registers with equalizing port g in the valve seat, permitting main-reservoir pressure to enter chamber D above the equalizing piston. If the handle were allowed to remain in this position, the brake system would be charged to main-reservoir pressure. To avoid this, the handle must be moved to Eunning or Holding posi- tion. To prevent the engineer from forgetting this, a small port discharges feed-valve pipe air to the atmosphere in release posi- tion. Cavity / in the rotary valve connects port d with warning port r in the seat and allows a small quantity of air to escape into the exhaust cavity ex, which makes sufficient noise to attract the engineer's attention to the position in which the valve handle is standing. The small groove in the face of the rotary valve which connects with port s, extends to port p in the valve seat, allowing main-reservoir pressure to flow to the excess-pressure head of the pump governor. Bunning Position. This is the proper position of the handle (a) when the brakes are charged and ready for use; (b) when the brakes are not being operated, and (c) to release the locomotive brakes. In this position, cavity / in the rotary valve connects ports h and d in the valve seat, affording a large direct passage from the feed-valve pipe to the brake pipe, so that the latter will charge up as rapidly as the feed valve can supply the air, but can- not attain a pressure above that for which the feed valve is adjusted. Cavity Tc in the rotary valve connects ports c and g in the valve seat, so that chamber D and the equalizing reservoir charge uniformly with the brake pipe, keeping the pressure on the two sides of the equalizing piston equal. Port s in the rotary valve 18 TEE AIE BEAEE, Connections : FV — Feed Valve Pipe ; MR — Main Reservoir Pipe; GO — To Governor ; III — Distributing- Valve Release Pipe ; EX — Emergency Ex- h a u s t ; II — Appli- cation c y 1 i n de r Pipe ; BP — P>rake Pipe ; GA-— No. 1 Duplex Air Gauge ; E R — Equalizing Reservoir ; BP Ex. — Service Exhaust. Fig. 19. H-6 Automatic Brake Valve. NO. 6 "E. T.'' EQUIPMENx. Fig. 20. The H-6 Automatic Brake Valve. 50 TBE AIB BRAKE. registers with port xj in the valve seat, permitting main-reservoir pressure, which is present at all times above the rotary valve, to pass to the excess-pressure head of the pump governor. Port h in the rotary valve registers with port I in the seat, connecting the distributing-valve-release pipe through the exhaust cavity ex with the atmosphere. If the brake valve is in running position when uncharged ears are cut in, or if, after a heavy brake application and release, the handle of the automatic brake valve is returned to running posi- tion too soon, the governor will stop the pump until the difference between the hands on gauge No. 1 is less than 20 pounds. The pump stopping from this cause, calls the engineer's attention to the seriously wrong operation on his part, as running position results in delay in charging, and is liable to cause some brakes to stick. Eelease position should be used until all brakes are released and nearly charged. Service Position. This position gives a. gradual reduction of brake-pipe pressure to cause a service application. Port h in the rotary valve registers with port e in the valve seat, allowing air from Chamber D and the equalizing reservoir to escape to the atmosphere through cavities o in the rotary valve and ex in the valve seat. Port e is restricted so as to make the pressure in the equalizing reservoir and chamber D fall gradually. As all other ports are closed, the fall of pressure in chamber D allows the brake-pipe pressure under the equalizing piston to raise it, and unseat its valve, allowing brake-pipe air to flow to the atmosphere gradually through the opening marked BP Ex. When the pressure in chamber D is reduced the desired amount, the handle is moved to lap position, thus stopping any further reduc- tion in that chamber. Air will continue to discharge from the brake-pipe until its pressure has fallen to an amount a trifle less than that retained in chamber D, permitting the pressure in this chamber to force the piston downward gradually and stop the dis- charge of brake-pipe air. It will be seen, therefore, that the amount of reduction in the equalizing reservoir determines that in the brake pipe, regardless of the length of the train. The gradual reduction of brake-pipe pressure is to prevent quick action, and the gradual stopping of this discharge is to prevent the premature release of head brakes. Lap Position. This position is used (a), while holding the brakes applied after a service application until it is desired either to make a further brake- pipe reduction, or to release them; and (b) to prevent loss of main-reservoir pressure in the event of a burst hose, a break-in-two, or the opening of the conductor's valve. All ports are closed. Release Position. This position, which is used for releasing the train brakes after an application, without releasing the locomotive brakes, is described under Charging and Release. The air flowing from the main-reservoir-pipe connection through NO. 6 "E. T.'' EQUIPMENT, 51 '^% Fig. 21. H-6 Automatic Brake Valve Eekcoved From Its Pipe Bracket. 52 TEE AIB BRAKE. port a in the rotary valve and port b in the valve seat to the brake pipe, raises the pressure in the latter, thereby causing the triple valves and equalizing portion of the dis- tributing valve to go to release position, which releases the train brakes and recharges the auxiliary reservoirs and the pressure ",hamber in the distributing valve. When the brake-pipe pressure has been increased sufficiently to cause this, the handle of the brake valve should be moved to either Running or Holding posi- tion; the former when it is desired to release locomotive brakes, and the latter when they are to be still held applied. Holding Position. This position is so named because the locomotive brakes are held applied while the train brakes recharge to feed-valve pressure. All ports register as in running positi6n, except port Z, which is closed. Therefore, the only difference between Running and Holding Positions is that in the former the locomotive brakes are released, while in the latter they are held applied. Emergency Position. This position is used when the most prompt and heavy application of the brakes is required. Port x in the rotary valve registers with port c in the valve seat, making a large and direct communication between the brake pipe and atmosphere through cavity o in the rotary valve and ex in the valve seat. This direct passage makes a sudden and heavy dis- charge of brake-pipe pressure, causing the triple valves and dis- tributing valve to go to the emergency position and give maximum braking power in the shortest possible time. In this position main-reservoir air flows to the application cyl- inder through port j, which registers with a groove in the seat connecting with cavity Ic; thence through ports n in the valve and u in the seat to the application-cylinder pipe, thereby maintaining application-cylinder pressure as already described and shown in Fig. 10. The oil plug 29 is placed in the top ease 4, at a point to fix the level of an oil bath in which the rotary valve operates. The posi- tion of this oil hole is such that it is impossible to pour oil into the valves in excess of the amount required. This arrangement furnishes thorough lubrication. Valve oil should be used. Leather washer 8 prevents air in the rotary-valve chamber from leaking past the rotary-valve key to the atmosphere. Spring 30 keeps the rotary valve key firmly pressed against washer 8 when no main-reservoir pressure is present. The handle 9 contains latch 11, which fits into notches in the quadrant of the top case, so located as to indicate the different positions of the brake-valve handle. Handle-latch spring 10 forces the latch against the quad rant with sufficient pressure to indicate each position. To remove the brake valve, close the cocks, as previously ex- plained, and take off nuts 27. (See Fig. 2L) To take the valve proper apart, remove cap screws 28. The brake valve should be located so that the engineer can NO. 6 ''E. T." EQUIPMENT. 5S Fig. 22. Valve, Complete. Fig. 23. EEMOVi^D From Pipe BfvACKet. 8-6 INDEPENDENT BEAKE VALVE. 54 TKE Am BEAKE. Fig. 24. The S-6 Independent Brake Valve. Connections: EV— Eeducing Valve Pipe; EX — Exhaust; IV — Distributing- Valve Eelease Pipe to the Distributing Valve; III — Distributing-Valve Eelease Pipe to the Automatic Brake Valve; II — Application-Clyinder Pipe. NO. 6 ''E. T." EQUIPMENT. 55 operate it conveniently from his usual position, while looking forward or back out of the side cab window. THE S-6 INDEPENDENT BKAKE VALVE. Fig. 22 and 23 illustrate this valve, which is of the rotary- type. Fig. 24 shows a vertical section through the center of the valve, and a horizontal section through the valve body, with the rotary valve removed, showing the rotary valve seat. Fig. 25 shows this valve similarly to Fig. 24, with the addition of a top view of the rotary valve. In these views the pipe connections and positions of the handle are indicated. Eeferring to Fig. 25, the names of parts are as follows: 2, Pipe Bracket; 3, Eotary-Valve Seat; 4, Valve Body; 5, Eeturn-Spring Casing; 6, Eeturn Spring; 7, Cover; 8, Casing Screw; 9, Eotary Valve; 10, Eotary-Valve Key; 11, Eotary-Valve Spring; 12, Key A¥asher; 13, Upper Clutch; 14, Handle Nut; 15, Handle; 16, Latch Spring; 17, Latch Screw; 18, Latch; 19, Cover Screw; 20, Oil Plug; 21, Bolt and Nut; 22, Bracket Stud; 23, Bracket-Stud Nut; 24, Upper Gasket; 25, Lower Gasket; 26. Lower Clutch; 27, Eeturn-Spring Stop; 28, Cap Screw. Port & in the seat leads to the Eeclucing-Valve pipe. Port a leads to that portion of the Distributing-Valve Eelease Pipe w^hich connects to the distributing valve at IV (Fig. 7). Port c leads to the other portion of the release pipe which connects to the automatic-brake valve at III (Fig. 19). Port d leads to the application-cylinder pipe which connects to the distributing valve at II (Fig. 7). Port h, in the center, is the exhaust port leading directly down to the atmosphere. Port k is the warning port, connecting with the atm.osphere. Exhaust cavity g in the rotary valve is always in communication at one end with exhaust port h. Groove e in the face of the valve communicates at one end with a port through the valve. This groove is always in communication with a groove in the seat connecting with supply port h, and through the opening just mentioned air is admitted to the chamber above the rotary valve, thus keeping it to its seat. Port m connects by a small hole with groove e; f is a groove in the face of the rotary valve; I consists of ports in top and face of valve connected by a passage. Bunning Fosition. This is the position that the independent brake valve should be carried in at all times when the independent brake is not in use. Groove f in the rotary valve connects ports a and c in the valve seat, thus establishing communication be- tween the application cylinder of the distributing valve and port I of the automatic brake valve (Fig. 19), so that the distributing valve can be released by the latter. It will also be noted that if the automatic brake valve is in running position, and the inde- pendent brakes are being operated, they can be released by sim- ply returning the independent valve to running position, as the 56 23 t[Hp\PE TA^ THE AIE BEAKE, B V ^/fpiPE TAP 1IHp\pe tap oJ0^r">'- Fig. 25. The 8-6 Independent Brake Valve. NO. 6 ''E. T." EQUIPMENT. 57 application-cylinder pressure can then escape through the release pipe and automatic brake valve. Slow-Application Position. To apply the independent brake lightly or gradually, move the brake-valve handle to the slow- application position; port m registers v^^ith port d, allowing air to flow from the reducing-valve pipe through port and groove & in the seat, groove e in the rotary valve, and the comparatively small port m to port d • thence through the application-cylinder pipe to the application cylinder of the distributing valve. Quick- Application Position. To obtain a quick application of the independent brake, move the brake-valve handle to quick- application position; groove e then connects ports & and d directly, making a larger opening between them than in the slow- application position, allowing supply air to flow rapidly from the reducing-valve pipe to the application cylinder of the dis- tributing valve. Since the supply pressure to this valve is fixed by the regula- tion of the reducing valve to 45 pounds, this is the maximum cyl- inder pressure that can be obtained. Lap Position. This position is used to hold the independent brake applied after the desired cylinder pressure is obtained, at which time all communication between operating ports is closed. Release Position. This position is used to release the pressure from the application cylinder when the automatic brake valve is not in running position. At such time the offset in cavity g reg- isters with port d, allowing pressure in the application cylinder to flow through the application-cylinder pipe, ports d, g and h to the atmosphere. The purpose of return spring 9 is to automatically move the handle 15 from the release to the running position, or from the quick-application to the slow-application position, as soon as the engineer lets go of it. The automatic return from release to run- ning position is to prevent leaving the handle in the former, and thereby make it impossible to operate the locomotive brake with the automatic brake valve. The action of the spring between quick-application and slow-application positions serves to ac- centuate the latter, so that in rapid operation of the valve, the engineer is less likely to unintentionally pass over it to the quick- application position, thereby obtaining a heavy application of the locomotive brake when only a light one was desired. As a warn- ing to the engineer in case of a broken return spring, port I in the face of the rotary registers in release position with port Tc in the seat, allowing air to escape to the atmosphere. The purpose of the oil plug 20 is the same as that described in the automatic brake valve. The location of this valve should be governed by the same con- siderations as those mentioned concerning the automatic brake valve. 58 THE AIB BEAKE. k I I «Q\a :.=iJ NO. 6 "E. T." EQUIPMENT. 59 Fig. 26 gives a top view of both brake valves, showing the position of their handles. THE B-6 FEED VALVE. The B-6 feed valve (Figs. 27 and 28), furnished with the No. 6 equipment, is an improved form of the slide-valve type. It differs from previous ones in charging to the regulated pressure somewhat quicker, and in maintaining thcr pressure more ac- curately under the variable conditions of short and long trains, and of good and poor maintenance. Also, it gives high and low brake-pipe pressure control. It is supplied with air directly from the main reservoir. It regulates the pressure in the feed-valve pipe, and also the brake pipe in running and holding positions of the automatic brake valve as the latter then connects these two pipes. It is connected to a pipe bracket located in the piping between the main reservoir and the automatic brake valve, and is interchangeable with previous types. Figs. 29 and 30 are diagrammatic views of the valve and pipe bracket having the ports and operating parts in one plane to facilitate description. The names of the parts shown in the dia- gram are as follows: 2, Valve Body; 3, Pipe Bracket; 5, Cap Nut; 6, Piston Spring; 7, Piston Spring Tip; 8, Supply-Valve Piston; 9, Supply Valve; 10, Supply- Valve Spring; 11, Kegu- lating-Valve Cap; 12, Kegulating Valve; 13, Kegulating-Valve Spring; 14, Diaphragm; 15, Diaphragm Ring; 16, Diaphragm Spindle; 17, Regulating Spring; 18, Spring Box; 19, Upper Stop ; 20, Lower Stop ; 21, Stop Screw ; 22, Adjusting Handle. This feed valve consists of two sets of parts, the supply and regulating. The supply parts, which control the flow of air through the valve, consist of the supply valve 9 and its spring 10; the supply -valve piston 8 and its spring 6. The regulating parts consist of the regulating valve 12, regulating-valve spring 13, diaphragm 14, diaphragm spindle 16, regulating spring 17, and regulating handle 22. Main-reservoir air enters through port a, a to the supply-valve chamber B, forces supply-valve piston 8 to the left, compresses piston spring 6 and causes the port in supply valve 9 to registei with port c (See Fig. 30). This permits air to pass through ports c and d to the feed-valve pipe at FVP, and through port e to diaphragm chamber L. Regulating valve 12 is then open and connects chamber G, on the left of piston 8, to the feed-valve pipe through passage h, port 1c, chamber L, and passage e, d, d. Air feeding by the piston cannot accumulate above feed-valve pipe pressure. When regu- • lating valve 12 is closed, the pressure on the left of piston 8 quickly rises, to the main-reservoir pressure on the right, and piston spring 6 forces piston 8 and supply valve 9 to the right, closes port c, and stops the flow to the feed-valve pipe. 60 Pig. 27. Valve and Pipe Bracket Complete. Fig. 28. Valve Eemoved From Pipe Bracket. THE B-6 FEED VALVE. NO. 6 "E. T.'' EQUIPMENT. 61 The regulating valve is ojDerated by diaphragm 14. When the pressure of regulating spring 17 on its right is greater than the feed-valve pipe pressure in chamber L on its left, it opens regu- lating valve 12. This causes the supply valve to admit air to the feed-valve pipe. When the feed-valve pipe pressure in chamber L is greater than that of the regulating spring 17, the diaphragm allows regulating valve 12 to close. This causes the supply valve to stop admitting air to the feed-valve pipe. As already explained under H-6 Autoniatic Brake Valve, in release position of the latter, the warning port is supplied from the feed- valve pipe. (See Fig. 20.) This insures that the excess- pressure governor head will regulate the brake-pipe pressure in release position even though the feed valve is leaking slightly, but not enough to be otherwise detrimental. The distinguishing feature of this type of feed valve is the duplex adjusting arrangement by which it eliminates the necessity of the two feed valves in high and low pressure service. The spring box, 18, has two rings encircling it, which are split through the lugs marked 19 and 20 in the diagram, and wdiich may be secured in any position by the screw 21. The pin form- ing part of adjusting handle 22, limits the movement of the handle to the distance between stops 19 and 20. When testing the valve, stop 19 is located so that the compression of spring 17 will give the desired high brake-pipe pressure, and stop 17 so that the spring compression is enough less to give the low brake-pipe pressure. Thereafter, by simply turning handle 22 until its pin strikes either one of these stops, the regulation of the feed valve is changed from one brake-pipe j)ressure to the other. To adjust this valve, slacken screws 21, wdiich allow^s stops 19 and 20 to turn around spring box 18. Adjusting handle 22 should be turned until the valve closes at the lower brake-pipe pressure desired, when stop 20 should be brought in contact with the handle pin, at which point it should be securely fastened by tightening screw 21. Adjusting handle 22 should then be turned until the higher adjustment is obtained, when stop 19 is brought in contact with the handle pin and securely fastened. We rec- ommend that the stops be placed to give 110 pounds high, and 70 pounds low, brake-pipe pressure. When replacing this feed valve on its pipe bracket after re- moval, the gasket, shown in Fig. 28, must always be in place be- tween the valve and bracket, to insure a tight joint. THE C-6 EEDUCINO YALVE. This valve, illustrated in Fig. 31^ is the well known feed valve that has been used for many years in connection with the G-6 brake valve, but in this equipment is attached to a pipe bracket. The only difference between it and the B-6 feed valve just described is in the adjustment, it being designed to reduce 62 THE AIB BBAKE. main-reservoir pressure to a single fixed pressure, which in this equipment is, as already stated, 45 pounds. To adjust this valve, remove the cap nut on the end of the spring box; this will expose the adjusting nut, by which the adjustment is made. It is called a ' ' Eeducing Valve ' ' when used with the independent brake and air-signal systems, simply to distinguish it from the feed valve supplying the automatic brake valve. THE SF TYPE OF PUMP GOVEKNOE. The duty of the SF Pump Governor is to sufficiently restrict the speed of the pump, when the desired mam-reservoir pressure is obtained, so as to prevent this pressure from rising any higher. During most of the time on a trip, the automatic brake valve is in running position, keeping the brakes charged. But little excess pressure is then needed, and the governor regulates the main- reservoir pressure to about 20 pounds only above the brake-pipe pressure, thus making the work of the pump easier. On the other hand, when the brakes are applied (lap position of the automatic brake valve, following the use of its service position) a high main-reservoir pressure is needed to insure their prompt release and recharge. Therefore, as soon as the use of lap, service or emergency positions is commenced, the governor allows the pump to work freely until the maximum main-reservoir pressure is ob- tained. Again, when the brake-pipe pressure is changed from one amount to another by the feed valve, as where a locomotive is used alternately in high-speed-brake and ordinary service, the gov- ernor automatically changes the main-reservoir pressure to suit, and at the same time maintains the other features just described. Another important feature is that, before commencing and during the descent of steep grades, this governor enables the engi- neer to raise and maintain the brake-pipe pressure about 20 pounds above the feed-valve regulation merely by the use of re- lease position of the automatic brake valve, the position which should be used during such braking. The following will explain the construction and operation of the SF Governor. Fig. 32 shows a sectional view of this governor with steam valve 5 open. By reference to the piping diagram in Fig. 1-B, connection B leads to the boiler; P to the air-pump; ME to the main reservoir ; ABV to the automatic brake valve ; FVP to the feed-valve pipe; W is the waste-pipe connection. Steam enters at B and passes by steam valve 5 to the connection P and to the pump. The governor regulating head on the left is called the ' * exctss-pressure head, ' ' and the one on the right the ' ' maximum- pressure head. ' ' Air from the main reservoirs flows through the automatic brake valve (when the latter is in release, running or holding position) to the connection marked ABV into chamber d NO. 6 ''E. T." EQUIPMENT, 63 Fig. 29. Diagram of B-6 Feed Valve, Closed. Connections: MR — Main-Eeservoir Pipe; FVP — Feed-Valve Pipe. 64 TEE AIB BRAKE. Fig. 30. Diagram or B-6 Eeed Valve, Open. Connections: See Fig. 29. NO. 6 "E. T." EQUIPMENT. 65 below diaphragm 28. Air from the feed-valve pipe enters at the connection FVP to chamber f above diaphragm 2S, adding to the pressure of regulating spring 27 in holding it down. As this spring is adjusted to about 20 pounds, this diaphragm will be held down until the main-reservoir pressure in chamber d slightly exceeds the combined air and spring pressure in chamber /. At such time, diaphragm 28 will rise, unseat its pin valve, and allow air to flow to chamber h above the governor piston, forcing the latter downward, compressing its spring and restricting the flow of steam past steam valve 5 to the point where the pump will just supply the leakage in the brake system. When main-reservoir pressure in chamber d becomes reduced, the combined spring and air pressure above the diaphragm forces it down, seating its pin valve. As chamber 6 is always open to the atmosphere through the small vent port c, the pressure in chamber & above the gov- ernor piston will then escape to the atmosphere and allow the piston spring, and steam pressure below valve 5, to raise it and the governor piston to the position shown. Since the connection from the main reservoir to chamber d is open only when the handle of the automatic brake valve is in release, running or hold- ing positions, in the other positions this governor head is cut out. The connection marked MR in the maximum-pressure head should be connected to the main reservoir cut-out cock, or to the pipe connecting the two main reservoirs, so as to be always in com- munication with the main reservoir, so that when the excess-pres- sure head is cut out by the brake valve, or by the main-reservoir tmt-out cock, this head will control the pump. When main-reser- voir pressure in chamber a exceeds the adjustment of spring 19 in the maximum-pressure head, diaphragm 20 will raise its pin valve and allow air to flow in to chamber & above the governor piston, controlling the pump as above described. The adjustment of spring 19 thus forms the maximum limit of main-reservoir pressure, as for example when the train brakes are applied. As each governor head has a vent port c, from which a small •amount of air escapes whenever pressure is present in port ft, to avoid an unnecessary waste of air, one of these should be plugged. To adjust the excess-pressure head of this governor, remove cap nut 25 and turn adjusting nut 26 until the compression of spring 27 gives the desired difference between main reservoir and brake-pipe pressures, the handle of the automatic brake valve being in running position. To adjust the maximum-pressure head remove cap nut 17 and turn adjusting nut 18 until the compres- sion of spring 19 causes the pump to stop at the maximum main- reservoir pressure required, the handle of the automatic brake valve now being on lap. It is recommended that spring 27 be ad- justed for 20 pounds excess pressure, and spring 19 for a pressure ranging from 120 to 140 pounds, depending on the service. TEE AIB BBAEE. Fm. 31. THii C-6 Eeducing Valve. NO. 6 "E. T." EQUIPMENT. 67 THE *' DEAD-ENGINE" FEATUEE. The "Dead Engine" feature shown in Fig. 1-A, and 1-B shown at Z, is for the operation of the locomotive brakes when the pump on a locomotive in a train is inoperative through being broken down, or by reason of no steam. Fig. 33 shows the com- bined strainer, check valve, and choke fitting. As these parts are not required at other times, a cut-out cock is provided. This cock should be kept closed except under the conditions just mentioned. The air for operating the brakes on such a locomotive must then be supplied through the brake pipe from the locomotive operating the train brakes. With the cut-out cock open, air from the brake pipe enters at BP, Fig. 33, passes through the curled hair strainer, lifts check valve 4, held to its seat by a strong spring, passes through the choke bushing, and out at MR to the main-reservoir, thus provid- ing pressure for operating the brakes on this locomotive. The double-heading cock should be closed, and the handle of each brake valve should be in running position. Where absence of water in the boiler, or other reason, justifies keeping the maximum braking power of such a locomotive lower than the standard, this can be accomplished by reducing the adjustment of the safety valve on the distributing valve. It can also be reduced at will by the independent brake valve. The strainer protects the check valve and choke from dirt. Spring 2 over the check valve insures this valve seating and, while assuring an ample pressure to operate the locomotive iDrakes, keeps the main-reservoir pressure somewhat lower than the brake- pipe pressure, thereby reducing any leakage from the former. The choke prevents a sudden drop in brake-pipe pressure and the appli- cation of the train brakes, as would otherwise occur with an un- charged main reservoir cut in to a charged brake pipe. In this, it operates similarly to the feed groove in a triple valve. MANIPULATION AND TEAIN HANDLING. The following instructions are general, and must necessarily t)e supplemented to a limited extent to fully meet the varying local conditions on different railways. The instructions for manipulating the ET equipment are prac- tically the same as those given for the combined automatic and straight air brake; therefore, no radical departure from present methods of brake manipulation is required to get the desired results. The necessary instructions are briefly as follows: When not in use, carry the handles of hoth 'brake valves in run- ning position. To apply the iraJces in service, move the handle of the auto- matic brake valve to the service position, making the required 68 THE AIR BRAKE. brake-pipe reduction, then back to lap position which is the one for holding brakes applied. To release the train brakes, move the handle to the release pa- sition and hold it there until all triple valves are in release posi- tion; if locomotive brakes are to be released at once, use runvAng position; but if they are to be held for a time, move to holding position, and then graduate them off by short, successive move- ments between running and holding positions. With all freight trains and especially long ones, both release and holding positions must, of course, be used very much longer than with short trains, particularly passenger. To apply the hrahes in emergency, move the handle of the automatic brake valve quickly to emergency position and leave it there until the train stops or the danger is past. To make a smooth and accurate two-application passenger stop, make the first application sufficiently heavy to bring the speed of train down to about 15 miles per hour at a convenient distance from the stopping point, then release train brakes by moving the handle to release position, then the locomotive brakes by moving it to running position for two or three seconds before re-applying. A little experience with the E. T. equipment Avill enable the engi- neer to make smooth and accurate stops with much greater ease than was heretofore possible. When using the independent hrahe only, the handle of the automatic brake valve should be carried in running position. The independent application may be released by moving the inde- pendent-brake-valve handle to running position. Independent re- lease position is for use only when the automatic-brake-valve handle is not in running position, as an example, when the engi- neer desires to release the engine brakes independent of the train brakes. While handling long trains of cars, in road or switching serv- ice, the independent brake should be operated with care, to pre- vent damage to cars and lading, caused by running the slack in or out too hard. In cases of emergency arising while the indepen- dent brake is applied, apply the automatic brake instantly. The safety valve will restrict the brake-cylinder pressure to the proper maximum. The brakes on the locomotive and on the train should be alter- nated in heavy grade service to prevent overheating of driving- wheel tires and to assist the pressure retaining valves in holding the train while the auxiliary reservoirs are being recharged. This is done by keeping the locomotive brakes released by use of the independent brake valve when train brakes are applied, and apply- ing locomotive brakes just before train brakes are released, and then releasing locomotive brakes after train brakes are reapplied. When all brakes are applied automatically, to graduate off or entirely release the locomotive hrakes only, use release position of the independent brake valve. NO. 6 "E. T." EQUIPMENT, ABV- -MR Fig. 32. The SF-4 Pump Governor. 70 THE AIB BEAKE. The red hand of gauge No. 2 (Fig. 1) will show at all times the pressure in the locomotive brake cylinders, and this hand should be observed in brake manipulation. Release Position of the Independent Brake Valve will release the locvnwtive hraTces under any and all conditions. The train brakes should invariably be released before detach- ing the locomotive, holding with hand brakes where necessary. This is especially important on a grade, as there is otherwise no assurance that the car, cars or train so detached will not start when the air brakes leak off, as they may in a short time where there is considerable leakage. The automatic brakes should never be used to hold a standing locomotive or a train even where the locomotive is not detached, for longer than ten minutes, and not for such time if the grade is very steep or the condition of the brakes is not good. The safest method is to hold with hand brakes only and keep the auxiliary reservoirs fully charged, so as to guard against a start from brakes leaking off, and to be ready to obtain any part of full braking power immediately on starting. The independent brake is a very important safety feature ir) this connection, as it will hold a locomotive with a leaky throttle or quite a heavy train on a fairly steep grade if, as the automatic- brakes are released, the slack is prevented from running in or out, (depending on the tendency of the grade) and giving the locomo- tive a start. To illustrate — the best method to make a stop on a descending grade is to apply the independent brake heavily as the stop is being completed, thus bunching the train solidly; then, when stopped, place and leave the handle of the independent brake valve in application position; then release the automatic brake?, and keep them charged. Should the* independent brake be unable to prevent the train from starting, the automatic brakes will be- come sufficiently recharged to make an immediate stop; in such an event enough hand brakes should at once be applied as are necessary to assist the independent brake to hold the train. Many runaways and some serious wrecks have resulted through failure to comply with the foregoing instructions. When leaving the engine while doing work about it, or when it is standing at a coal chute or water plug, always leave the inde- pendent-brake-valve handle in application position. In case the automatic brakes are applied by a bursted hose, a break-in-two or the use of a conductor's valve, place the handle of the automatic brake valve in lap position. Where there are two or more locomotives in a train, the double- heading cocJc must Ite closed, and the handle of the automatic brake valve must be carried in running position on each except the one from which the brakes are being operated. Before leaving the round house, the engineer should try the brakes with both brake valves, and see that no serious leaks exist. NO. 6 "E. T," EQUIPMENT. TJr. 72 THE Alii BRAKE. The pipes H and I (Fig. 1-B) between the distributing valve and the brake valves should be absolutely tight. QUESTIONS AND ANSWERS ON NO. 6 ET LOCOMOTIVE BRAKE EQUIPMENT.* Q. 1. What is the No. 6 ET Equipment? A. It is a brake equipment for engine and tender adapted to all kinds o2 engines and classes of service and combines the opera- tive features of the standard automatic, straight-air, high-speed, and double pressure control brake equipments, with many ad- ditional features. Q. 2. ■ Is the operation of the train brakes affected by the ET Equipment? A. No ; the operation of the train brakes is the same with this equipment as with former locomotive brake equipments. Q. 3. What is meant by the term train brakes? A. All brakes in the train except those upon the locomotive from which the brakes are being handled. Q. 4. WJiat is meant by the term locomotive brake? A. The brake upon the engine and tender. Q. 5. What new features of operation are obtainable with the ET Equipment? A. (a) Locomotivfe brake may be used with or independently of the train brakes, whether the train brakes are in use or not. (b) Uniform and proper cylinder pressure is obtained regardless of piston travel or leakage. (c) Cylinder pressure is automatically maintained re- gardless of brake cylinder leakage. (d) Locomotive brake can be graduated on or off with either the automatic or the independent brake valves. (e) Increased flexibility in service operations, with in- creased braking power in. emergency applications. (f) Brakes on second locomotive or helper can be released or applied without in any way interfering with any other brakes in the train. PARTS OF THE EQUIPMENT. Q. 6. Name the essential parts of the ET Equipment. A. 1, Air Compressor; 2, Main Reservoir; 3, Duplex Pump Governor ; 4, Feed Valve ; 5, Reducing Valve ; 6, Automatic Brake Valve with Equalizing Reservoir; 7, Independent Brake Valve; 8, *Formulatea by The Air Brake Association. .\(). 6 ''E. T." EQUIPMENT. 73 Distributing Valve and Double Reservoir; 9, Two Duplex Air Gages ; 10, Combined Air Strainer and Check Valve ; 11, Choke Fitting ; 12, Locomotive Brake Cylinders ; also various cocks and fittings. (See Figs. 1-A and 1-B.) Q. 7. What special parts are sometimes used? A. (a) Quick-action Cylinder Cap for Distributing Valve. (b) Combined Air Strainer and Check Valve for Train Air Signal System. (c) Choke Fitting for Truck Brake. Q. S. What furnishes the compressed air for the brake sys- tem? A. The Air compressor. Q. 9. What operates the air compressor? A. Steam from the locomotive boiler. Q. 10. After leaving the compressor, where does the air go? A. Through the radiating pipes to the main reservoir. Q. 11. What is the purpose of the radiating pipe? A. To cool the air after leaving the compressor. Q. 12. What is the purpose of the main reservoirs? A, The main reservoirs provide a place for the storage of an abundant supply of compressed air for use in promptly releasing the brakes on the locomotive and train and for recharging the brake system. They also assist in cooling the compressed air and collect moisture, oil or other foreign matter, allowing only cleau, dry air to pass to the brake system. Q. 13. What controls the air pressure in the main reservoirs? A. The Duplex pump governor. Q. 14. How does the pump governor control the main reser- voir pressure? A. It automatically regulates the supply of steam to the com- pressor so as to maintain normal pressure in the main reservoirs. Q. 15. What connects the main reservoirs to the brake sj'S- tem? A. The main reservoir pipe. Q. 16. What provision is made for cutting off the main res- ervoirs from the rest of the brake system? A. A cock in the main reservoir pipe close to the main reser- voir, known as the "main reservoir cut-out cock." Q. 17. Where do the pipe branches lead to from the main reservoir pipe? A. (a) To the duplex pump governor. (b) To the main reservoir hand of the duplex air gage. (c) To the automatic brake valve. 74 THE AIR BRAKE. (d) To the feed valve. (e) To the reducing valve. (f) To the distributing valve. (g) To the dead engine fixtures. (h) Other branches leading to various air-using devices on the locomotive, such as sanders, water-scoop, etc. Q. 18. Wihat is the purpose of the feed valve? A. To automatically maintain a predetermined pressure in the brake system, lower than that carried in the main reservoirs. Q. 19. To what does the feed valve pipe connect? A. To the automatic brake valve, and to the spring chamber of the excess pressure head of the duplex pump governor. Q. 20. What is the purpose of the reducing valve? A. It automatically reduces the air pressure from the main reservoirs to the proper pressure used with the independent brake and train air signal system. Q. 21. What is the purpose of the automatic brake valve? A. (a) To allow air to Jow from the brake system for charg- ing it. (b) To discharge air from the brake pipe to the atmos- phere to apply the brakes. (c) To prevent the flow of air to or from the brake pipe when holding the brakes applied. (d) To hold applied or release the locomotive brake as desired while releasing train brakes. (e) To allow air to flow to the brake system for the pur- pose of releasing the brakes and recharging the system. (f) To control the flow of air to the diaphragm chamber of the excess pressure head of the duplex pump governor. (g) To allow main reservoir to flow to the appli- cation cylinder of the distributing valve in emer- gency position. Q. 22. What is the purpose of the independent brake valve? A. To operate the brakes on the engine and tender independ- ent of the train brakes. Q. 23. State briefly the purpose of the distributing valve. A. (a) To automatically control the flow of air from the main reservoirs to the engine and tender brake cylinders when applying the brakes, (b) To automatically maintain the brake cylinder pressure against leakage, keeping it constant, when holding the brake applied. NO. 6 ''E. Tr EQUIPMENT. 75 (c) To automatically control the flow of air from the engine and tender brake cylinders to the atmos- phere when releasing the brake. Q. 24. What is the purpose of the locomotive brake cylinders? A. The brake cylinder is that part of the air brake equip- ment in which the force contained in the compressed air is trans- formed into a mechanical force which is transmitted through a suitable combination of rods and levers to the brake shoes and applies them to the wheels. H-6 AUTOMATIC BRAKE VALVE. Q. 25. How many positions has the H-G Brake Valve? A. Six. Q. 26. Name the positions beginning at the left. A. Release, Running, Holding, Lap, S^ervive and Emergency (SCO Fig. 19). Q. 27. Name and describe the purpose of the pipe connec- tions to the ri-G Brake Valve. A. (a) Main Reservoir Pipe. To connect the main reservoirs to the chamber above the rotary valve and permit a free flow of liigh pressure air imto the brake pipe when the brake valve handle is in release position. (b) Feed Valve Pipe. To connect the feed valve to the underside of the rotary valve. When the brake valve handle is in running position this pipe is open to the brake pipe, thus permitting the feed valve to maintain a constant brake pipe pressure below that in the main reservoirs. (c) Equalizing Reservoir Pipe. This connects the cham- ber above the equalizing piston to the equalizing reservoir and the equalizing reservoir gage. (d) Brake Pipe. To connect the distributing valve on the locomotive and the triple valve on each car to the space underneath the equalizing discharge pis- ton and the underside of rotary valve. (e) Governor Pipe. This makes a connection from the rotary valve chamber (main reservoir pressure) to the underside of the diaphragm of the excess pres- sure governor head when the brake valve handle is in either release, running or holding positions. (f) Distributing Valve Release Pipe. This makes a con- nection from the application chamber of the dis- tributing valve (through the independent brake valve) to the underside of the automatic rotary 76 THE AIR BRAKE. valve, forming a connection to the atmosphere when both brake valve handles are in running position, (g) Application cylinder Pipe. This connects the under- side of the automatic rotary valve directly to the application cylinder of the distributing valve. In emergency position of the brake valve handle this pipe is open to the chamber above the rotary valve (main reservoir pressure) through the blow-down timing port. Q. 28. When is release position used? A. When it is desired to quickly charge the brake system and to release brakes on long trains. , Q. 29. Explain the flow of air through the automatic brake Yalve when in release position. A. Air from the main reservoirs flows directly to the brake pipe, equalizing reservoir and pump governor. Air from the feed valve flows through the warning port to the atmosphere. Q. 30. When is running position used? A. When running along the road to maintain a predeter- mined brake pipe pressure lower than that carried in the main reservoirs, to release the engine and tender brakes and also to release the brakes on short trains. Q. 31. Explain the flow of air through the automatic brake valve when in running position. A. (a) Air from the feed valve flows to the brake pipe and to the equalizing reservoir. (b) Aiv from the main reservoirs flows directly to the diaphragm chamber of the excess pressure head of the duplex pump governor, (c) Air from the distributing valve release pipe flows to the atmosphere. Q. 32. When is holding position used? A. When it is desired to hold the engine and tender brakes applied by means of the automatic brake valve while releasing and recharging the train brakes. Q. 33. Explain the flow of air through the automatic brake valve when in holding position. A. The flow of air through the automatic brake valve when in holding position is the same as when in running position with one exception, namely : air from the distributing valve release pipe is prevented from flowing to the atmosphere. Q. 34. When ds lap position used? A. When holding all the brakes applied after an automatic application. The handle should never be carried in this position except while bringing the train to a stop. AO. 6* "y;. 7'." EQUIPMENT. 77 Q. 35. Is there any flow o'i air to the brake system through the automatic brake valve when in lai) position V A. No. Q. 30. When is service position used? A. When it is desired to make an automatic application of the brakes. Q. 37. Explain fully the flow of air through the automatic brake valve when in service position. A. In the automatic brake valve is a piston and valve called the equalizing discharge piston and valve, No. 15, Fig. 19. The underside of this piston is directly connected to the brake pipe. The chamber D, above piston 15, is directly connected to the equal- izing reservoir ER and to a small port e in the rotary valve seat called the preliminary exhaust port. In service position the prelim- inary exhaust port is open to the atmosphere through port h and exhaust cavity o (see small view plan of Rotary A'alve at right, Fig. 20) in the rotary valve, thus {allowing air from the equilizlhg reser- voir and the chamber D above the equalizing discharge piston to flow to the atmosphere. This reduces the pressure on the top of the piston below the brake pipe pressure on the underside, which raises the equalizing discharge piston 15 and permits brake pipe air to flow to the atmosphere through the service exhausit fitting B. P. Eae. The flow of air from the equalizing reservoir to the at- mosphere continues until the brake valve handle is returned to lap position. This closes the preliminary exhaust port e, and pre- vents further decrease of pressure in the equalizing reservoir and chamber D. Air will continue to discharge from brake pipe until its pressure has been reduced slightly lower than that remaining in chamber D. The higher pressure on the top of the piston then forces the valve to its seat and prevents further reduction of brake pipe pressure. Q. 38. What is the purpose of the service exhaust fitting? A. To fix the maximum permissible opening from the brake pipe to the atmosphere when making a service application. Q. 39. Is it important that all H-6 brake valves be provided with this fitting? A. Yes. Q. 40. When is emergency position used? A. When it is desired to make the shortest possible stop. In such case the handle should be moved to emergency position quickly and left there until the train stops. Q. 41. Should this position be used at any other time? A. Yes ; this position should be used in case of an emergency application of the brakes from an unknown, cause, such as the 78 THE AIR BRAKE. opening of a conductor's valve, bursted hose, etc., in order to pre- vent loss of main reservoir pressure and to insure a full applica- tion of the brakes and the handle should be left there until signal to release is given. Q, 42. Why should emergency position be used as explained in the last answer instead of lap position? A. To insure the brakes remaining applied under all circum- stances. Q. 43. Explain the flovs^ of air through the automatic brake valve vs^hen in emergency position, A. A large and direct opening is made from the brake pipe to the atmosphere, through the rotary valve, causing a quick and heavy reduction of brake pipe pressure. At the same time ithe air in the equalizing reservoir escapes to the atmosphere through ports in the rotary valve. Connection is made from air at main reser- voir pressure above the rotary valve through a restricted port in the rotary valve to the application cylinder pipe leading to the ap- plication cylinder of the distributing valve. This port is known as the blow-down timing port, and assists in building up and reg- ulating application cylinder pressure during emergency application. S-6 INDEPENDENT BRAKE VALVE. Q. How many positions has the S-6 Brake Valve? A. Five. Q. 45. Name the positions beginning at the left. A. Release, Running Lap, Slotv- Application and Quick-Appli- cation (see Fig. 24). Q. 4G. Name and describe the purpose of the pipe connec- tions to the S-6 Brake Valve. A. (a) Reducing Valve Pipe. This is the only source of air supply to the valve and connects the reducing valve to the chamber above the rotary valve, and through ithe rotary valve when the independent brake valve handle is in either application position, to the application cylinder and chamber of the distribut- ing valve and also through the warning port to the atmosphere when the handle is in release posi- tion. (b) Distributing Valve Release Pipe to the distributing valve. Connects the application chamber of the distributing valve to the underside of the independ- ent brake valve. When the brake valve handle is in running position, this pipe is connected through ports in the seat and cavities in the rotary valve to the automatic brake valve. (c) Distributing Valve Release Pipe to the automatic 'brake valve. This pipe oonneets the underside of NO. 6 ''E. r." EQUIPMENT. 79 the i-otary valve of the independent brake valve to the undei-side of the rotary valve of the auto- matic brake valve. With both brake valve handles in running position, free passage is made from the application chamber of the distributing valve to the atmosphere through this pipe. (d) Application Cylinder Pipe. Connects the application cylinder to the underside of the rotary valve of the independent brake valve. When the handle is in either application position air from above the ro- tary valve flows through this pipe to the applica- cation cylinder and chamber of the distributing valve. When the handle is in release position this pipe is connected to the atmosphere through ports in the rotary valve and seat. Q. 47. When is release position used? A. Whenever it may be necessary to release the brake when the automatic brake valve handle is not in running position. Q. 48. Explain the flow of air through the independent brake valve when in release position. A. Air from the application cylinder of the distributing valve flows direct through the application cylinder pipe and independent brake valve to ithe atmosphere. At the same time air from above the rotary valve (reducing valve pressure) flows through the ro- tary valve and warning port to the atmosphere. Q. 49. When is running position used? A. When running along the road and to release the locomo- tive brake after an independent application, the automatic brake valve handle being in running position. Q. 50. Explain the flow of air through the independent brake valve w^hen in running position. (Automatic brake valve handle in running position.) A. Air from the application chamber of the distributing valve flows through the distiibuting valve release pipe and independent brake valve, then through the automatic brake valve to the atmos- phere. Q. 51. When is lap position used? A. When holding the engine and tender brake applied after an independent application. Q. 52. Is there any flow of air through the independent brake valve when in lap position? A. No. Q. 53. When is slow-application position used? A. When it is desired to apply the locomotive brakes lightly or gradually. 80 THE Alii lih'AKlJ. Q. 54. Explain the flow of air through the independent brake valve when in. sloic-wpplication position. A. Air flows from the chamber above the rotary valve through the restricted service port and application cj^'linder pipe into the application cylinder and chamber of the distributing valve. Q. 55, When is quick-application position used? A. When it is desired to apply the locomotive brakes promptly. Q. 56. Explain the flow of air through the independent brake valve when in quick-application position. A. Air, flows from above the rotary valve through a full open service port in the rotary valve and the application cylinder pipe to the application cylinder and chamber of the distributing valve. Q. 57. What prevents the independent brake valve handle from remaining in release position or in quick-application position unless held there? A. A return spring. Q. 58. To what position does the return spring move the brake valve handle from relea\sc position? A. To rnniiii.g position. Q. 59. Why is this necessary? A. To prevent the possibility of the independent brake, valve handle being left in release position, which would cause the engine and tender brakes to release whenever an automatic ap- plication was made. Q. 60. To what position does the return spring move the brake valve handle from quick-application position? A. To slotv-ap plication position. Q. 61. Why is the spring used for this purpose? A. To act as a stop, guarding against a quick application vrhen only a slow application is intended, and to return the handle from quick to slow-application position. Q. 02. Why is this latter necessary? A. In order to limit the flow of air to the application cylinder when the independent brake is to be left applied. NO. 6 DISTRIBUTING VALVE WITH PLAIN CYLINDER CAP. Q. 63. What controls the brake cylinder pressure on the locomotive with No. 6 ET equipment? A. The distributing vaive. Q, 64. How does it do this? A. It permits air to flow from the main reservoirs to the brake cylinders when applying the brake, from the cylinders to 2V0. 6 ''E. 7'." EQUIPMENT. 81 the atmosphere when releasing the brake, and automatically main- tains the pressure against leakage, keeping it consitant, when hold- ing the brake applied, Q. 65. Is the amount of air flowing from the main reservoirs to the brake cylinders limited by the distributing valve? A. Yes ; the distributing valve acts as a reducing valve in supplying air from the main, reservoirs to the locomotive brake cylinders. Q. GG. Facing the distributing valve, name the two pipes on the right hand side of the reservoir and state to what each one connects (see Fig. 5). A. (a) The upper pipe on the right is the brake cylinder pipe. It connects the distributing vaive to all the brake cylinders on the engine and tender, (b) The lower pipe on the right is the brake pipe branch pipe. It connects the distributing valve to the brake pipe. Q. G7. iSame the three pipes on the left hand side of the res- ervoir and state to what each one connects (see Fig. 5). A. (a) The upper pipe on the left is the supply pipe. It con- nects the distributing valve to the main reservoir pipe. (b) The intermediate pipe is the application cylinder pipe. It connects the distributing valve to both the auto- matic and independent brake valves. (c) The lower pipe is the release pipe, which connects the distributing valve to the independent brake valve and through it to the automatic brake valve. Q. 68. How many chambers has the distributing valve res- ervoir? A. Two. Q. 69. Name them. A. Pressure chamber and application chamber (see Fig. 4). Q. 70. How many pistons has the distributing valve? A. Two. Q. 71. Name them. A. Application piston 10 and equalizing piston 2G. Q. 72. How^ many slide valves has the distributing valve? A. Four. Q. 73. Name them. A. Application valve 5, exhaust valve 16, equalizing valve 31 and graduating valve 28. Q. 74. What valves are operated by the application piston? A. The application valve and exhaust valve. Q. 75. What valves are operated by the equalizing piston? 82 THE AIR BRAKE. A. The equalizing valve and graduating valve. . Q. 76. With the brake released what pressures are present in the distributing valve? A. Main reservoir pressure, brake pipe pressure and aitmos- pheric pressure. Q. 77. In what portion of the distributing valve is main res- ervoir pressure? A. In chamber a, Fig. 7, above the application valve. Q. 78. In what portion of the distributing valve is brake pipe pressure? A, In the pressure chamber and in the chamber above the equalizing valve and graduating valve. Q. 79. In what portion of the distributing valve is atmos- Ijheric pressure? A. In chamber & above the exhaust valve 16 and on the right hand side of the application piston 10 ; in chamber g on the left hand side of the application piston (called the application cylinder) and in the application chamber and the ports and cavities con- necting to them. Q. 80. How is chamber a charged with air at main reser- voir pressure? A. Through the branch pipe leading from the main reservoir pipe to the connection marked MR on the distributing valve reser- voir. Q. 81. Describe the operation of the distributing valve parts when an independent application of the brake is made. A. Air is admitted to the application cylinder g and the ap- plication chamber from the reducing valve through the independ- ent brake valve and the intermediate pipe on the left (application chamber pipe). This pressure will force the application piston 10 to the right, Fig. 12, lapping exhaust ports d and e with ex- haust valve 16, and compressing graduating spring 20 and open supply port 6 through the application valve 5 to the brake cylinder chamber h, which is connected to the right of the application pis- ton, obtaining a brake cylinder pressure slightly exceeding that in the application cylinder, when it and the graduating spring 20 then moves the piston 10 and the application valve 5 back to lap position Fig. 13. The exhaust valve 16 will remain lapped, as there is suflicient clearance between the shoulders of the piston stem and the exhaust valve to permit the application valve to re- turn to lap without moving the exhaust valve. At the same time cavity s in the equalizing valve 31 registers with ports h and I in the seat, thus connecting the application cylinder port li to the safety valve. The equalizing piston and slide valve do not move during an independent application of the hraJce. NO. 6 "E. Tr EQUIPMENT. 83 Q. 82. Describe the operation of the distributing valve parts when an independent release of the brake is made. A. By a proper movement of the independent brake handle air from the application cylinder g and the application chamber is allowed to flow to the atmosphere, which reduces Che pressure in chamber g below that in chamber &, causing the application piston 10 to move to the left, carrying with it application valve 5 and exhaust valve 16 until iwrts d and e are open past and through exhaust valve 16, Fig. 7, permitting the air in the brake cylinders to flow through port c into chamber 6, thence through ports d and e to the exhaust and atmosphere. The equalizing pis- ion and its valves do not move during an independent release cf the irakes. Q. 83. How is the pressure chamber charged with air at brake pipe pressure? A. Through 'the branch pipe leading from the brake pipe to the connection marked BP on the distributing valve reservoir, Fig. 5, leading into chamber p, Fig. 7, then through feed gixjove v around top of piston 26 into the chamber above the equalizing valve 31 and through port o to the pressure chamber until the pressure on both sides of 'the piston are equal. Q. 84. From where do the application cylinder and chamber receive their air? A. From the redueing valve through the independent brako valve during independent applications and from the pressure cham-. her during automatic service applications. Q. 85. Describe the operation of the distributing valve parts when an automatic service application of the brake is made. A. The brake pipe pressure in chamber p on the brake pipe side of equalizing piston 26 being reduced below that in the pres- sure chamber on the opposite side of the piston results in piston 26 being moved toward the right. The first movement of piston 26 closes the feed groove v, and at the same time moves the grad- uating valve 28 until it opens the service port z in the equalizing valve, and sired in the main reservoirs. Q. 148. Explain the operation, of the governor when main reservoir pressure in chamber "a" exceeds the tension of spring 19. A. When main reservoir pressure in chamber a slightly ex- ceeds the adjustment of spring 19, diaphragm 20 will rise, unseat its pin valve 33, and allow air to flow into chamber & above the governor piston, forcing it down, compressing its spring 9 and restricting the flow of steam past steam valve 5 to a point where the compressor will just supply the leakage in brake system. Q. 149. How long will the flow of steam through the gov- ernor be restricted in this manner? A. When main reservoir pressure in chamber a becomes slightly reduced, the spring 19 forces diaphragm 20 down, seat- ing its pin valve. As chamber 6 is always open to the atmos- phere through the small vent port c, the pressure in chamber h above the governor piston 6 will then escape to the atmosphere and allow the piston spring 9 and steam pressure below valve u to raise the valve and governor piston to the position shown. Fig. 32. Q. 150. Is the maximum pressure head of the governor in any way controlled by the automatic brake valve? A. No ; as the chamber a below the diaphragm is in no way connected to the brake valve. Q. 151. With the automatic brake valve handle in Jap, service or emergency positions or when the main reservoir cut- out cock is closed why does not the excess pressure head operate instead of the maximum pressure head? A. Because under these conditions, communication from the main reservoir to chamber d is cut off by the brake valve and at the same time connection from the feed valve pipe to chamber f above diaphragm 28 still remains open, so that the combined air and spring pressure on top of the diaphragm holds the pin valve to its seat, rendering the excess pressure head inoperative. Q. 152. Under ordinary running conditions, why is only a moderate excess pressure desirable? A. Because most of the time the automatic brake valve handle is in running position, (keeping the brakes charged) but little 94 THE AIR BRAKE. excess pressure is needed and the governor regulates the main reservoir pressure to about 20 pounds above the brake pipe pressure, thus relieving the compressor of unnecessary work. Q. 153. When an application of the brakes is made, why is the higher excess pressure of advantage? A. To insure a prompt release of the brakes and recharge of the system. DEAD ENGINE FIXTURES. Q. 154. What are the parts composing . the dead engine fixtures. A. A % -inch pipe connecting the brake pipe and main reser- voir pipe, a combined strainer and check valve with choke fitting, and a %-inch cut-out cock. Q. 155. What is the purpose of the "Dead Engine" feature of the ET Equipment? A. To enable the compressor on a "live" engine to charge the main reservoir on a "dead" engine, so that the brake on the dead engine may be operated with the other brakes in the train. Q. 156. How is this done? A. Air from the main reservoir of the live engine passes through the brake pipe and dead engine fixtures to the main reservoirs of the dead engine. Q. 157. When is this apparatus used? A. Only when the air compressor on the locomotive is in- operative. Q. 158. Should the cut-out cock always be closed except when the compressor is inoperative? A. Yes. Q. 159. Describe the flow of air through the combined strainer and check valve. Fig. 33. A. With the cut-out open, air from the brake pipe enters at BP, passes through the curled hair strainer, lifts check valve 4, held to its seat by a strong spring 2, passes through the choke bushing, and out at MR to the main reservoir pipe. Q. 160. Why is the "strong" spring 2 used in this valve? A. This spring over the check valve insures the valve seating and keeps the main reservoir pressure somewhat lower than the brake pipe pressure, yet assures ample pressure to operate the locomotive brakes. Q. 161. What is the object of the choke fitting? A. It prevents a sudden drop in brake pipe pressure and the application of the brakes in the train, as might otherwise occur with uncharged main reservoirs cut into a charged brake 2^0. 6 *'E. T." EQUIPMENT. 05 pipe or if for any reason the main reservoir pressure was lower than the brake pipe pressure. Q. 162. How can the maximum brake cylinder pressure be regulated on a dead engine? A. By the adjustment of the safety valve on the distributing valve. Q. 163. Can the brake on a dead engine be controlled with the independent brake valve the same as on a live engine? A. Yes, if it becomes necessary. Q. 164. When the dead-engine feature is used, in what position should the automatic and independent brake valve handles be carried? A. Running position. Q. 165. What should be the position of the double heading cock? A. Closed. Q. 166. Is it sometimes desirable to keep the braking power of a locomotive below the standard? A. Yes ; when there is no water in the boiler. Q. 167. How is this done? A. By adjusting the safety valve on the distributing valve •to the maximum brake cylinder pressure which is desired in the locomotive brake cylinders. AIR GAGES. Q. 168. How many and what type of gages are used in connection with the ET Equipment? A. Two duplex gages, designated — No. 1, Large Duplex Air Gage; No. 2, Small Duplex Air Gage. (See Figs. 1-A and 1-B.) Q. 169. What pressures are indicated by gage No. 1 .' A. Red Hand, Main Reservoir Pressure ; Black Hand, Equal- ising Reservoir Pressure. Q. 170. What pressures are indicated by gage No. 2? A. Red Hand, Brake Cylinder Pressure ; Black Hand, Brake Mpe Pressure. Q. 171. Which gage hand shows the amount of reduction being made during a service application of the brakes? A. Black Hand, Gage No. 1. Q. 172. Why, then, is the black hand of gage No. 2 necessary? A. To show brake pipe pressure when engine is second in double-heading or a helper. Q. 173. What pressure is indicated by the red hand of gage No. 2 when operating the automatic or independent brake valve? A. Brake cylinder pressure. 96 THE AIR BRAKE. CUT-OUT COCKS. Q. 174. What provision is made for cutting off the main reservoirs from the brake sj^stem? A. The main reservoir cut-out cocli in the main • reservoir pipe. Q. 175. What takes place when this cock is closed? A. The flow of air from the main reservoirs is cut off and the air iQ the brake system back of it is exhausted to the atmosphere. Q. 176. When this cock is closed can air flow from the main reservoirs to any part of the system? A. Yes ; to the maximum pressure head of the pump governor. Q. 177. Why is this necessary? A. To provide for the automatic control of the compressor when the cut-out cock is temporarily closed. Q. 178. What provision is made for cutting out the driver brake ? A. A %-inch cut-out cock located in the pipe leading from the distributing valve to the driver brake cylinders. Q. 179. What provision is made for cutting out the tender brake? A. A %-iiich cut-out cock located in the pipe between the dis- tributing valve and the hose connection leading to the tondor brake cylinder. Q. 180. What difference is there between this cock and the %-inch cocks generally used? A. It has a choke fitting. Q. 181. Why is this choke fitting used? A. To prevent a loss of driver and truck brake cylinder pressure in the event of a hose or tender brake cylinder pipe bursting. Q. 182. Is there another cock with choke fitting sometimes used in connection with this apparatus? A. Yes ; when a truck brake is used a ^-inch cock is located in the pipe leading from the distributing valve to the truck brake cylinder with choke fitting. Q. 183; For what purpose is the %-inch cut-out cock in the main reservoir supply pipe to the distributing valve? A. To cut off the supply of air from the main reservoirs to the distributing valve to permit of inspection and repairs. Q. 184. For what purpose is the one-inch double heading cock underneath the brake valve? A. To cut off the flow from the automatic brake valve to the brake pipe or vice versa. J NO. 6 "^. Tr EQUIPMENT. 97 Q. 185. What is the purpose of the brake pipe air strainer. A. To prevent foreign matter entering the distributing valve, which might seriously interfere w^ith its proper operation. AIR SIGNAL SYSTEM. Q. 186. From what source is the supply of air to the signal system obtained with the ET Equipment? A. From the reducing valve pipe between the reducing valve and the independent brake valve, as shown in Figs. 1-A and 1-B. Q. 187. Why is this supply taken, from the reducing valve pipe? A. That the one resition, tae main reservoir and brake pipe pressures do not stand 20 pounds apart, where is the trouble? A. In the adjustment of the excess pressure head of the pump governor. Q. 320. What should then be done? A. The excess pressure head of the pump governor should be properly adjusted. Q. 321. Before commencing to adjust the excess pressure head, what is it important to note? A. First — That the maximum pressure head is adjusted higher than the standard main reservoir pressure to be carried with the handle of the brake valve in running position. Second — That the air brake pressure is known to be correct. Third — • That there is no obstruction either in the main reservoir con- nection to the chamber under the diaphragm of the excess pres- sure head or in the pipe connection to the spring chamber. Q. 322. How should the adjustment of the excess pressure head be made? A. Remove the cap nut from the excess pressure head and screw the regulating nut up or down, as may be required. Q. 323. With the automatic brake valve handle in lap posi- tion if the main reservoir pressure varies from the maximum em- ployed on the road, where is the trouble? A. In the maximum pressure governor head. Q. 324. If such variation exists, what should be done? A. The maximum head should be properly adjusted. Q. 325. In case of a steady blow of air from the vent ix)i't when the compressor is operating, where is the trouble? A. A leak past the seat of one or both of the diaphragm pins valves. FEED VALVE TEST. Q. 326. How should the B-6 feed valve be tested? A. With brake released and system charged to standard pressure, open the angle cock at the rear of the tender suf- ficiently to represent a brake pipe leakage of from seven to ten pounds per minute and observe the brake pipe gage pointer. Q. 327. With this amount of brake pipe leakage, what should the brake pipe gage pointer do? A. It should fluctuate. Q. 328. What does this fluctuation of the gage pointer in- dicate? 112 THE AIR BRAKE. A. The opening and closing of the supply valve of the feed valve. Q. 329. If the gage hand does not fluctuate, what does it indicate ? A. That the supply valve piston is too loose a fit, and that the brake pipe leakage is being supplied past this piston and the regulating valve. Q. 330. How much variation should there be between the opening and closing of the feed valve supply valve? A. Not more than two pounds. Q, 331. If the variation is more than two pounds, what does it indicate? A. Undue friction of the parts or a sticky or dirty condi- tion of the operating parts of the valve, causing insufficient open- ing past the piston. Q. 332. If the feed valve charges the brake pipe to a pres- sure higher than that for which it is adjusted, what does it in- dicate ? A. That the piston has been made too tight a fit by oil or water. Q. 333. If the feed valve charges the brake pipe too slowly when nearing its maximum, what does it indicate? A. Either a loose fitting piston or a gummy condition of the regulating valve. REDUCING VALVE TEST. Q. 334. How should the C-6 reducing valve be tested? A. First, with the system charged to standard pressure, fully apply the independent brake (handle in slow-application position) and note the amount of brake cylinder pressure ob- tained. Q. 335. What should this pressure be? A. Forty-five pounds Q. 336. If, in this test, the brake cylinder pressure is other than forty-five pounds, what does it indicate? A. A leaky supply valve, a leaky regulating valve, or that the reducing valve is out of adjustment. Q. 337. After completing the test, what next should be done? A. Release the brake and make an application in quick-ap- plication position. Q. 338. How can the reducing valve be tested for sensi- tiveness ? IVO. 6 "^. 7'." EQUIPMENT. 113 A. By applying a test sage to the signal line hose, and pro- duce a leakage of from seven to ten pounds per minute in the signal line pipe and note the fluctuation of the gage pointer. Q. 339. What is important in making this test? A. It must be known that the combined strainer and check valve is in a condition to permit a free flow of air through it. Q. 340. What other diseases might affect the operation of the reducing valve? A. Those given in questions 329 to 333 for the feed valve. AUTOMATIC BRAKE VALVE TEST. Q. 341. What should be observed concerning the automatic brake valve? A. That all its pipe connections are tight and that the handle moves freely between its various positions and that the handle latch and its spring are in good condition. Q. 342. If the handle does not operate easily, what are the probable causes? A. A dry rotary valve sent, n dry rotary valve key gasket or a dry handle laloh. Q. 343. What should be done? A. Rotary valve and seat, rotary valve key and handle latch should be properly lubricated. Q. 344. What is the proper method of lubricating the valve and seat? A. Close the double-heading cock under the brake valve, then the main reservoir cut-out cock and after the air pressure has escaped, remove the oil plug in the valve body and fill the oil hole with valve oil. Q. 345. After filling the oil hole and before replacing the oil plug, Avhat should be done? A. The handle should be moved a few times between release and emergency positions to permit the oil to work in between the rotary valve ana its seat. The oil hole should then be re- filled and the oil plug replaced. Q. 34G. Ho'W should the rotary valve key and gasket be lubricated? A. Remove the cap nut from the rotary valve key and fill the oil hole, Q. 347. Before replacing the cap nut, what should be done? A. Push down on. the key and rotate the handle a few times between release and emergency positions ; then refill the oil hole and replace the cap nut. 114 THE AIR BRAKE. Q. 348. If the handle latch becomes dry, what should be done ? A. Lubricate the sides of the latch and the notches on the quadrant. Q. 349. If, with the handle in release, running, holding or lap positions, there is a leak at the brake pipe service exhaust, what does it indicate? A. That the equalizing piston valve is unseated, probably due to foreign matter, Q. 350. How can this leak usually be stopped? A. By closing the double-heading cut-out cock under the brake valve, making a heavy service application and returning the brake valve handle to relealse position. This will cause a heavy blow at the service exhaust fitting and usually remove the foreign matter and allow the valve to seat. Q. 351. With the handle of the automatic brake valve in service application position, brake pipe pressure seventy pounds, how long should it take to reduce the equalizing reservoir pres- sure twenty pounds? A. From six to seven seconds. Q. 352. From a brake pipe pressure of 110 pounds, how long should it take? A. From five to six seconds. Q. 353. In case the equalizing reservoir pressure reduces considerably faster than the time given, what is the probable cause ? A. Either an enlarged preliminary exhaust port, leakage past the rotary valve, seat, lower gasket, or in the equalizing reser- voir and its connections to the brake valve or gage. Q. 354. If the reduction, is materially slower than the figures given, what is probably the cause? A. A partial stoppage of tLe preliminary exhaust port or leakage into the equalizing reservoix. Q. 355. How should test be made for a leaky rotary valve? A. By placing the brake valve handle in service position and allowing it to remain there until the brake pipe gage pointer drops to zero ; then close the double-heading cock under the brake valve and place the brake valve handle on lap. If a blow starts at the brake pipe exhaust, it indicates a leak by the rotary valve into the brake pipe ; if an increase of pressure is noted on the equalizing reservoir gage it indicates a leak past the rotary valve or body gasket into the chamber above the equalizing piston and reservoir. Q. 356. During this test, if an increase of brake cylinder pressure results or the safety valve blows intermittently, what does it indicate? 2V0. 6 "E. Tr EQUIPMENT. 115 A. A leak by the rotary valve into the application cylinder of the distributing valve. Q. 357. With the brake valve handle on lap position after making a service application, if the brake pipe service exhaus: continues to blow and the air gage indicates a fall in pressure in both the equalizing reservoir and brake pipe, vv^here should the trouble be looked for? A. In the equalizing reservoir and its connections, both to the brake valve and to the air gage, and also the inner tube of the gage. INDEPENDENT BRAKE VALVE TEST. Q. 358. What are the important things to observe in con- nection with the independent brake valve? A. That no external leakage exists in the brake valve or its pipe connections and that the handle and return spring work freely and properly. Q. 359. What can cause the handle to move hard? A. Lack of lubrication on the rotary valve and seat, rotary valve key and gasket or handle latch, same as with the auto- matic brake valve. Q. 360. What should be done to make the handle move freely? A. Follow the same recommendations as prescribed for the automatic brake valve. Q. 361. Should the handle continue to work hard after the parts have been lubricated, where is the trouble? A. Probably something is wrong with the return spring or its housing. Q. 362. How should test for leaky rotary valve be made? A. Make a partial independent application of the brakes, place the handle on lap, and note if brake cylinder pressure in- creases gradually to the limit of adjustment of the reducing valve. Q. 363. Should the handle fail to automatically return to running position or to slow-application position, what is the prob- able cause ? A. Too much friction of the moving parts or a weak or broken return spring. DISTRIBUTING VALVE TEST. Q. 364. With the system charged to standard pressure, if a five-pound service reduction in brake pipe pressure fails to apply the locomotive brake, what is the probable cause? A. Excessive friction in one or more of the operative parts of the distributing valve. 116 THE AIR BRAKE. Q. 365. How should the test be made to determine which of the operating parts caused the trouble? A. By recharging and then making a slow independent appli- cation. If the brake applies properly, the indications are that the trouble is in the equalizing portion of the distributing valve ; if it does not, the indications are that it is in the application portion. Q. 366. How frequently should the distributing valve be cleaned and oiled? A. At least every six months. Q. 367. What parts of the distributing valve should be lubricated ? A. All operating parts. Q. 368. If water is found in the distributing valve, what is usually the cause? A. Improper piping on the locomotive ; not sufficient length of radiating pipe between the compressor and reservoirs. Q. 369. How should the equalizing piston, slide valve and graduating valve be removed from the distributing valve? A. Remove the equalizing cylinder cap and carefully pull out the piston, and valves so as not to injure them, Q. 370. Ho'w should the application piston, application valve and exhaust valve be removed? A. First take off the application valve- cover and remove the valve, then take out the application valve pin, after which the application cylinder cover should be removed and the piston and exhaust valve carefully pulled out. Q. 371. Must the application valve pin always be removed before attempting to take out the application piston and exhaust valve? A. Yes ; if this is not done, damage will result, as the piston cannot be taken out unless the pin is removed. Q. 372. With the valves removed from the distributing valve, what should be done? A. Air should be blown through the ports and passages to remove any foreign matter. Q. 373. Before assembling the parts, what should be done? A. All seats and bushings should be thoroughly cleaned and carefully examined to see that no lint is on the seats. Q. 374. What else should be given attention? A. The feed groove in the equalizing piston bushing should be carefully cleaned out. Q. 375. What should be the resulting brake cylinder pres- sure from a ten-pound brake pipe reduction? :S^0. 6 "E. Tr EQUIPMENT. 117 A. About twenty-five pounds. Q. 370, For each pound reduction of biake pipe pressure, what should be the resulting brake c.vlinder pressure? A. About two and one-half pounds. Q. 377. If, after a partial service application has been made and the brake valve lapped, the brake cylinder pressure con- tinues to increase, what are the causes? A. The most probable cause is brake pipe leakage. Others may be a leak past the automatic rotary valve, the independent rotary valve, the equalizing valve, or the graduating valve in the distributing valve. Q. 378. What brake pipe pressure should be used when testing the ET Equipment? A. Seventy pounds. Q. 379. Why? A. With seventy pounds brake pipe pressure the point of equalization is below the adjustment of the safety valve. W'ith 110 pounds pressure the point of equalization is above the adjust- ment of the safety valve and therefore leakage could not be so easily discovered. Q. 380. How is the source of leaks determined? A. By making a partial service application and observe to what figure the brake cylinder pressure rises. If it increases to fifty pounds and remains constant, it indicates brake pipe leakage. Q. 381. If the increase in the brake cylinder pressure is due to a leaky rotary in tne automatic brake valve, how may it be detected ? A. The brake cylinder pressure will increase up to the limit of adjustment of the safety valve, causing it to blow. Q. 382. If brake cylinder pressure increases to forty-five pounds and stops, where may the trouble be looked for? A. In the independent brake valve, due to a leaky rotary. Q. 383. With the safety valve removed and the brake ap- plied with a partial service application, if a continuous leak exists at the safety valve connection to the distributing valve, what would probably be the cause? A. A leaky graduating or equalizing valve. Q. 384. If the equalizing valve leaks, how can it be de- tected? A. By a steady discharge of air through the exhaust port of the automatic brake valve when the handle of both this brake valve and the independent brake valve is in runninrj position. Q. 385. If, with a service application there is an intermit- tent blow at the brake cylinder exhaust port, what does it in- dicate? 118 THE AIR BRAKE. A. A leaky application valve, provided the application cy)« Inder and the application cylinder pipe is tight. Q. 386. What indicates exhaust valve leakage? A. A continuous discharge of air from the exhaust port whefi the brake is applied. Q. 387. If after a service application the equalizing piston, slide valve and graduating valve move to release position be- cause of graduating valve leakage, will the locomotive release? A. On the engine from which the brakes are being operated the locomotive brake will not release, but on the second engine in double headers or helpers with the brake valves cut out (doubh>- heading cock closed) the locomotive brake will release. Q. 388. Why does not the brake release on the locomotive from which the brakes are being operated? A. Because under these conditions the automatic brake valv« is on lap; consequently the air cannot exhaust from the applic?\« tion chamber. Q. 389. Why will the brake release on the second locom(- tive or helper? A. Because the release pipe is open to the atmosphere. Q. 390. If the brake released after an automatic applicji* tion, when the handle is placed in release or holding position, buc remains applied after an independent application, where wouM you look for the trouble? A. It is caused by a leak from the distributing valve re- lease pipe, between the automatic and the independent .braki<» valves. Q. 391. If the brake releases after an independent applica^ tion, but remains applied after an automatic application, what would cause the trouble? A. A leak in the distributing valve release pipe between the distributing valve and the independent brake valve. Q. 392. If the brake releases after either an automatic or an independent application, what would cause the trouble? A. A leak from the application cylinder pipe or past the application cylinder cap gasket. Q. 393. How could a weak or broken application piston graduating spring be detected? A. If this spring becomes weak or broken, the application portion of the distributing valve would not be as sensitive to graduation. Q. 394. How should test for leakage in the application cyV- inder pipg be made? 1^0. 6 "^'. t:' equipment. 119 A. Make a service application of the brake, lap the handle and note if the brake remains applied. If it does not, it indicates that the application cylinder pipe or possibly that the applica- tion cylinder cap gasket is leaking. Q. 395. To determine if the release pipe is leaking, how should test be made? A. Make a service application of the brake with the auto- matic brake valve. If the brake remains applied with handle in lap position but releases when handle is returned to holding, it indicates release pipe leakage. Q. 396. If the brake cylinder pressure does not remain at that to which it is applied, what is the cause? A. Leakage from application chamber, application cylinder or their pipe connections. BRAKE CYLINDER LEAKAGE TEST. Q. 397. Can brake cylinder leakage be readily determined with ET Equipment? A. Yes. Q. 398. How? A. By noting the number of strokes which the compressor makes in a given period of time. Then apply the brake with the independent brake valve and after the compressor has restored the main reservoir pressure again note the number of strokes. The dif- ference in the number of strokes indicates the amount of leak- age in the brake cylinders. Q. 399. Is there any other method of determining brake cylinder leakage? A. Yes ; apply the brake with the independent brake valve, then close the cut-out cock in the distributing valve supply pipe and observe the brake cylinder gage. The gage will indicate the amount of leakage from the brake cylinders. Q. 400. Can it be determined which of the brake cylinders is leaking? A. Yes. Q. 401. How? A. Apply the brake with the independent brake valve and close the cut-out cock in the distributing valve supply pipe, then close the cut-out cocks in the pipes leading to the truck brake cylinder, driver brake cylinder and tender cylinder in order, not- ing the gage after each cock is closed. SAFETY VALVE TEST. Q. 402. What attention should be given the E-6 Safety Valve? 120 THE AIR BRAKE. A. It should be noted that the safety valve is screwed prop- -erly in place, that the cap nut is screwed down on the regulating nut, making an air tight joint with the body, and that all vent holes and ports are open. Q. 403. If the cap nut is not screwed down properly, what would be the effect? A. The valve and its stem would have too much lift and the leakage of air around the threads of the regulating nut to the atmosphere would interfere with its proper operation. Q. 404. How should the safety valve be tested to determine if it is properly adjusted? A. Make an emergency application of the brake, allowing the handle to remain in emergency position, and note if the proper brake cylinder pressure is obtained. Q. 405. What brake pipe pressure should be used when test- ing the safety valve? A. 110 pounds. Q. 40G. Within what limits should the safety valve limit the locomotive brake cylinder pressure? A. Between 68 and 70 pounds. Q. 407. If the safety valve is adjusted at 68 pounds, and the pressure increases above 70 pounds, what would be the cause? A. The holes leading from the spring chamber of the valve are restricted or the piston valve has worn loose. Q. 408. If the safety valve permits the pressure to reduce considerably below 68 pounds before closing, niiat would be the trouble ? A. The holes leading from the spring chamber of the valve have been enlarged or gum or dirt has made the piston valve too close a fit. Q. 409. Within what limits should the safety valve limit the locomotive brake cylinder pressure for ordinary service appli- cations (110 lbs. brake pressure)? A. Between 65 and 70 pounds. AIR SIGNAL SUFPLY SYSTEM TEST. Q. 410. In testing the air signal, what should first be done? A. The signal pipe should be charged and all stop cocks, joints and unions carefully examined for leakage. Q. 411. How can it be determined whether the proper pres- sure is being carried in the signal line? A. By attaching a test gage to the signal line hose. NO, 6 "^. 2'." EQUIPMENT. 121 Q. 412. What would a too high signal pipe pressure indi- cate? A. That the reducing valve was improperly adjusted or was leaking. Q. 413. What effect might this have? A. In combination with a leaky signal line it might cause the signal whistle to blow when an independent application of the brake is made. Q. 414. How can reducing valve leakage be determined? A. Bj^ making a signal pipe reduction and noting if the pres- sure gradually increases after the standard maximum signal .pipe pressure has been attained. Q. 415. With a reasonably tight signal pipe, if the whistle blows when an independent application of the brake is made, what would be the cause? A. A leaky check valve in the combined strainer and check valve. Q. 416. If, in charging up the signal pipe the test gage indi- cates a too slow increase of pressure, where should the trouble be looked for? A. Probably an obstruction in the strainer or choke fitting or a loose fitting feed valve piston. Q. 417. If, Avith the signal system of the locomotive fully charged, the signal whistle blows, what is the probable cause? A. Leakage in the signal system and a sluggishly operating reducing valve. I PART II. THE NEW YORK B-3 LOCOMOTIVE BRAKE EQUIPMENT. I THE NEW YORK B-3 LOCOMOTIVE BRAKE EQUIPMENT. This locomotive brake equipment is known as the B-3 equip- ment, and is arranged in four different schedules to cover the gen- eral requirements of railroad service. Schedule B-3 is for engines in passenger or freight service, where but one brake pipe pressure is used. Both pump governor and pressure controller have single regulating heads, which should be adjusted for the standard brake pipe and main reservoir pres- sure. Schedule B-3S is for switch engines only. A single pump governor and single pressure controller are used. The controller -.s set to give a brake pipe pressure of 70 pounds and the pump governor for 90 pounds main reservoir pressure, for ordinary- switching service. However, when the engine is used for passen- ger switching service, and handles trains that are using 110 pounds brake pipe pressure, the pump governor should be adjusted to 110 pounds main reservoir pressure. "When handling a train using the bigh pressure, close cock No, 2 between the regulating and supply TJortions of the controller. This renders the controller inoperative, •allowing the main reservoir pressure of 110 pounds to pass to the Drake valve and brake pipe, so that trains using the high speed t>rake can be handled without delay without the necessity of carry- :.iig additional apparatus. A quick release valve is furnished with ■ihis schedule, to be placed in the straight air pipe, so that the brakes can be released quickly, permitting quicker movement. The divided reservoir and accelerator valve are not furnished with this schedule. The supplementary reservoir is substituted for the divided reservoir. Schedule B-3HP is for freight service where heavily loaded trains are handled on heavy grades, or loads handled down grades and empties up. Both regulating portions of the pump governor and pressure controller are duplex, so that pressures of 70 and 90 pounds can be carried in the brake pipe and 90 and 110 pounds in the main reservoir for the ordinary brake pipe pressure and the ijigh pressure control. 126 THE AIB BRAKE. For the operation of these duplex regulating portions, three- way cocks are provided, being connected as shown in the piping diagram. To operate these cocks, turn the handle in line with the pipe leading to the regulating head to be used, high or low pres- sure as desired. This will cut in the head to regulate the supply portion, and cut off the pressure to the one not in use. Schedule B-3HS is the high speed brake. It includes the duplex pressure controller and the duplex pump governor. The regulating heads of the pressure controller should be adjusted to 70 pounds and 110 pounds for brake pipe pressure, and the pump governor heads adjusted to 90 pounds and 130 pounds for the main reservoir pressure. A union four-way cock is used with the regulating heads of the pressure controller. This is a special cock with a connection to each regulating top, one to the supply pipe, between the controller and brake valve, and one to the pipe between the brake valve and accelerator reservoir. When the handle of the four-way cock is in the position to operate the regu- lating head adjusted to 110 pounds brake pipe pressure, a small port in the accelerator reservoir connection is brought into com- munication with a port to the atmosphere. The object of this port is to prevent more than the usual predetermined reduction of brake pipe air, obtained in the graduating notches, taking place with 110 pounds pressure. A union three-way cock connected to the main reservoir and pump governor regulating tops is used to change the main reservoir pressures. The piping diagrams of the four schedules of the B-3 equip- ment, shows the several parts comprising each schedule, as well as the proper pipe connections. This equipment is an improve- ment on former equipments. It not only includes all necessary features for the automatic brake, but also a straight air brake for the locomotive and tender, all operated by the automatic brake valve, without any additional positions. Some of the notable improvements incorporated in the B-3 brake valve, which will be appreciated by those who come In con- tact with it, are : the use of tap bolts instead of screws to fasten the valve cover to the body; port O is cored in the valve body instead of being drilled through the cover; the projection for cen- tering the piston packing leather EV 107 is on the piston instead of on the follower. A new packing leather can now be applied without removing the piston from the brake valve. It is only necessary to remove the back cap and the piston follower. Other parts of the equipment fully described under their dif- ferent headings are the li/4'' pressure controller by which tho brake pipe pressure is regulated ; the accelerator valve which assists the brake valve in discharging brake pipe air when making service applications with long trains, the %" controller which controls the straight air brake pressure; the high speed controller which acts as a reducing valve for the driver and truck brake cylinders, the lever safety valve and the quick release valve. N^ Y. B-S EQUIPMENT. 127 MANIPULATION. To apply the automatic brakes on the locomotive and train, move the handle of the brake valve to the graduating notch nec- essary to make the required brake pipe reduction. To release both locomotive and train brakes, move the handle to Eunning and Straight air release position. To release the train brakes and hold the locomotive brakes set, move the handle to Automatic release and Straight Air Applica- tion position. To apply the locomotive brakes (Straight Air), move the handle to Full Automatic release and Straight Air Application position. To release the locomotive brakes move the handle to Eunning and Straight Air release position. To apply the brakes in an emergency, move the handle quickly to Emergency position and leave it there until the train stops. In case the automatic brakes are applied by the bursting of a hose, the train parts, or a conductor's valve is opened, place the handle in Lap position to retain the main reservoir pressure. To graduate off or entirely release the locomotive brakes while holding the train brakes applied, use the lever safety valve to make the required reduction. The handle of the brake vUlve will be found to^ work freely and easily at all times, as the pressure on the main slide valve does not exceed the maximum brake pipe pressure. The cylinder gauge will shoAV at all times the pressure in the locomotive brake cylinder and should be observed in brake manip- ulations. Where there are two or more locomotives in a train, cut-out cock No. 1 should be turned to close the brake pipe and the brake valve handle carried in Eunning and Straight Air release position on all locomotives except the one from which the brakes are oper- ated. In case it becomes necessary to cut out the Straight Air brake, close cut-out cock No. 3, located in the straight air pipe. To cut out the automatic brake on the engine, close cut-out cock No. 6, located in the pipe connecting the triple valve with the double check valve. By locating the cut-out cock at this point the auxiliary reservoir will remain charged if the brake is cut out, and can be cut in immediately should it be so desired. This cut- out cock and also cut-out cock No. 3 are special; they are of the three-way pattern and when turned off drain the pipes leading to the double check valve, which insures the check valve remaining seated in the direction of the closed cock. If desired, cut-out cock No. 8 can be substituted for cock No. 6; the latter is, how- ever, recommended. The main reservoir cock No. 4 is to cut off the supply of air when removing any of the apparatus except the governor. 12S TEE AIB SHAKE. B-3 Brake Valve. N. Y. B-3 EQUIPMENT. 13) The straight air controller is to limit the pressure in the driver, truck and tender brake cylinders for the straight air brake, and should be adjusted to 40 pounds pressure. Cut-out cocks Nos. 5, 6 and 7 are recommended when truck brake is used, their purpose being fully understood. Nos. 9 and 10 can be added, if desired, so that the driver brake cylinders and reservoir can be cut out and engiue truck brake operated by truck, brake reservoir. B-3 BKAKE VALVE. Figure 1 is a longitudinal side section of the brake valve (Eun- ning position), showing the main slide valve EV 312, and how the graduating valve EV 317 is controlled by the piston EV 311 and lever EV 302, also port O in the back cap, closed by the vent valve, EV 180. This view also shows the different positions of the brake valve handle. Fig. 3 is a cross section through the valve (rear view). Fig. 4 is a cross section through the main slide valve, EV 312. This view shows the main reservoir and brake pipe connection. It also shows the location of passage H, which connects the supplementary reservoir and chamber D, back of piston EV 311, also port O drilled to the slide valve seat and cavity E in the slide valve. Fig. 2 is a top view of the valve with the cover, slide valve and handle removed, showing the seat and connections for the straight air and divided reservoir pipes. A shows the opening through the slide valve seat to the brake valve chamber A, beneath the slide valve. B is a cavity back of the slide valve seat, into which the air flows from the main reser- voir pipe, although all the space under the valve cover and above the slide valve is known as chamber B. C is the exhaust passage. V is through to the exhaust passage and is an exhaust port for the straight air brake in running and straight air release positions, and is also an exhaust port for the air from chamber D, through port O in the release, running and lap positions. Port T is to the accelerator reservoir. Port W is to the passage H and the sup- plementary reservoir. The location of port O in the seat is also shown. Port is used for the purpose of venting air from chamber D to the atmosphere, so as to permit piston EV 311 to return to its normal position (Fig. 1), when releasing brakes. It runs from the vent valve seat through the back cap, lengthwise through the body of the brake valve to a point shown in Fig. 4, thence up to the seat of the slide valve. It is connected to the exhaust passage by cavity E in the slide valve, and port V in the seat, in full re- lease, running and lap positions. Chamber D air is prevented from escaping to the atmosphere in these positions by the vent valve EV 180 on the end of piston EV 311. Just before the slide valve reaches the first graduat- ing notch, it covers port O, so that when the piston moves forward 180 THE Am BRAKE. EV3C(7 Eveo EVI58 -3" COPPER PIPE TO ACCELERATOR' RESCRVOIft n> * ffiXi @ MdgM±mXi '\epp\^^--A " '-b ■^"-mi O SUPPLEMENTARV Fig. 2. N. Y. B-3 EQUIPMENT. 13] to automatically close the service exhaust port F, and unseats vent valve EV 180, chamber D air only gets to the face of the slide valve. When the brake valve is placed in the full release, running or lap positions, air from chamber D flows through port O, cavity E and port V to the atmosphere until the pressure in chamber D is slightly below that in chamber A (brake pipe), when the brake pipe pressure being the greater it forces piston EV 311 to the po- sition shown in Fig. 1, seating the vent valve, and preventing fur- ther escape of chamber D air. EV 326 is a pipe bracket bolted to the side of the brake valve. It has two pipe connections, one to the main reservoir and the other to the brake cylinders. Dotted lines show the cored passage from the main reservoir connection to port N, and from port E to the cylinder pipe connection. Figure 5 shows the face of the slide valve. F and G are the service exhaust ports and are connected by a passage through the center of the slide valve. J and K are the emergency exhaust ports connected by passages on each side of the central passage, connecting F and G. S is a small port connected by passage X to the elongated port Ac, which registers with port T in the seat in all the service application positions. P is a groove whose func- tion is to connect port W and the supplementary reservoir Avith brake pip? pressure in release and running positions. L is a passage through which air passes from the main reservoir pipe to the brake cylinder pipe in straight air application position. R is a cavity connecting ports E and V in the running and straight air release positions to release the straight air brake and and V in release, running and lap positions. It also permits the partial opening of port N to E in the last graduating notch and full open- ing in emergency position. Ports M are through the slide valve and are for charging the brake pipe. Main reservoir air, reduced to brake pipe pressure by the pres- sure controller, flows into chamber B. The slide valve EV 312 controls the flow of air from the main reservoir to the brake pipe and from the brake pipe to the atmosphere. The brake pipe i^ connected to chamber A. Discharge of brake pipe air to the atmosphere for service applications occurs through ports F and G and exhaust passage C, but for emergency applications through ports J and K and exhaust passage C. In full automatic release position air is free to pass from the main reservoir to the brake pipe through ports M, and past the end of the slide valve EV 312. In the running position ports M only are open betewen the main reservoir and brake pipe, but they are sufficiently large to permit release of train brakes. Small slide valve EV 317 is a cut-off or graduating valve operated by piston EV 311 and lever EV 312. In service applications it automatically laps port F and stops the discharge of brake pipe air when the brake pipe reduction corre- sponding to the service graduating notch in which the handle is placed has been made. Piston EV 311, which is exposed on one N. Y. B-3 EQUIPMENT. 133 side to brake pipe pressure and on the other to chamber D or sup- plementary reservoir pressure, through the agency of lever EV 302 causes valve EV 317 to move automatically v^^hatever distance is necessary to close port F. W N L E V O Fig. 6. EELEASE POSITION. Automatic Release and Straight Air Application Position (Fig. 6). The purpose of this position is to promptly release and recharge the automatic brakes and to apply the straight air brakes or retain the pressure in the locomotive and tender brake cylinders. In this position air flows directly from chamber B (main reservoir), into chamber A (brake pipe), past the end of the slide valve and through ports M. Port O is open to the at- mosphere through port V to permit piston EV 311 to return to its normal position. Port T is open to the atmosphere through J and C. The supplementary reservoir is being charged to brake pipe pressure through groove P and port W from chamber A. Port E is brought into communication with port N by passage L, permit- ting air to pass to the locomotive and tender brake cylinders through the straight air pipe and double check valve until shut off by the %" pressure controller, the regulating top of Avhich is con- nected to the straight air pipe and adjusted at 40 pounds. By placing the valve handle about midway between release and run- ning positions the straight air ports can be lapped, making it pos- sible to increase or decrease the brake cylinder pressure as may be necessary. RUNNING POSITION. Running and Straight Air Release Position (Fig. 7). This is the proper position in which to place the handle when wishing to release the train and locomotive brakes simultaneously, or to release the straight air brake when it only has been applied. 1^4 TEE AIR BRAKE. A F S J C T X Ac W N Fig. 7. L E J V EuNNiNG Position. Air passes from the main reservoir to the brake pipe through ports M. Port N is closed. Port E is brought into communication with port V and the atmosphere by cavity E, releasing the straight air brake. Ports and T are still open to the atmosphere as in full release position. Port T is open to the atmosphere through J and C in release and running positions, so that in case of a re- lease follovring a partial application, the accelerator reservoir pressure can escape and prevent the operation of the accelerator valve. Groove P still holds port W in communication with the brake pipe pressure in chamber A. WLNJERVO Fig. 8. Lap Position. Lap Position (Fig. 8). The brake valve handle should be placed in this position when a hose bursts, the train parts or a conductor's valve is opened to save the main reservoir air. All ports are closed in this position excepting port O, which is open to the atomsphere through port V and the exhaust passage in re- lease, running and lap positions. Service Application Position (Figs. 9 and 10). This position is for the purpose of gradually applying the brakes and is divided N. Y. B-3 EQUIPMENT. I3r, into five graduating positions designated by notches on the quad- rant. The reductions obtained in the different notches are re- spectively, 5, 8, 11, 15 and 23 pounds. The amount of the initial reduction should always be governed by the length of the train, AFSJCTXAc WLNJERVO Fig. 9. First Graduating Notch. speed, grade, etc. Always place the handle of the brake valve in the notch which will give the required reduction. When the handle of the brake valve is moved to the first graduating notch the slide valve is in the position shown. Port U is closed to pre- vent the escape of chamber D pressure. Port F is moved back of the graduating valve EV 317 and port G registers with the ex- haust port C. Brake pipe air now flows to the atmosphere. It also flows through port S, passage X and port T to the accelerator reservoir, building up a pressure to operate the accelerator valve. LWNJREVO Fig. 10. Last Graduating Notch. As soon as the pressure in the brake pipe reduces, the pressure in chamber D, being now greater than brake pipe pressure, it begins to expand to equalize with the brake pipe pressure. In doing so it moves piston EV 311 forward. The piston carries with it the lao TEE AIB BRAKE. lower end of the graduating valve lever EV 302, which is so pro- portioned that the graduating valve EV 317, on the other end of it, is just moved back far enough to close ports F and S when the pressures in chamber D and the brake pipe have equalized. U W J N R E Fig. 11. Emergency Position. This stops the flow of air from the brake pipe to the atmosphere and to the accelerator reservoir (see accelerator valve). This action is called automatic lap and it takes place in all the graduat- ing positions. A further reduction of the brake pipe pressure is made by moving the handle back to any of the service notches, the piston moving farther forward for each successive reduction. The EVI5( EV60 EVI5I Fig. 12. Supplementary Eeservoir. Used With Switch En- gine Equipment, Schedule B3-S. action of the brake valve is the same and the ports are in the same relation to each other in all service positions of the brake valve except the last graduating position. In this position a partial i N. Y. B-3 EQUIPMENT. 137 opening of port N admits air slowly to the locomotive and tender brake cylinders through cavity E and port E up to the adjustment of the controller on the straight air pipe. This is to insure full braking pressure on the engine with a full application, regardless of piston travel and brake cylinder leakage. Emergency Application Position (Fig. 11). This position is for the purpose of producing a quick, heavy reduction in brake pipe pressure so that all triple valves on the train will operate in quick action and apply the brakes in the shortest possible time. Ports J register with chamber A and K with the exhaust port C, allowing brake pipe air to escape rapidly to the atmosphere. Cavity R allows air from the main reservoir to pass through ports N and E to the locomotive brake cylinders, and the full pressure of the straight air. brake is maintained on the engine. PEESSUEE CONTEOLLEE. The pressure controller is in reality, a part of the brake valve, taking place of the excess pressure or feed valves, and is connected in the main reservoir pipe near the brake valve to control brake pipe pressure. The principle of operation is the same as a pump governor. The regulating and supply portions are separate, being connected by piping, and the regulating heads connect directly to the pipe between the supply portion and the brake valve. With the pressure controller the excess pressure is confined to the main reservoir, and while it has suflScient capacity to promptly release the brakes and recharge the auxiliary reservoirs on a train of any length, there is no danger of overcharging the auxiliary reservoirs on the forward end of the train. Thus the possibility of reapplication, due to the charging of the rear brakes when the auxiliary reservoirs on the forward end are overcharged, which is common without the use of the controller, is eliminated. The controller is made in two styles, single and duplex, to cover the requirements of the different schedules. Figs. 14 and 15 are photographic views of a duplex pressure controller, regu- lating and supply portions. Fig. 16 is a sectional view of a duplex regulating portion and Fig. 17 a similar view, of a single regulating portion. Figs. 18 and 19 show the four-way, three- way and cut-out cocks, which are used to control the air pressure to the regulating heads. Fig. 21 is a sectional view of the supply portion. Eef erring to Fig. 21, connection with the main reservoir is made at ME, and by means of the cored passage air is free to pass to the under side of the valve, PG 95. Connection BV leads to the brake valve, main reservoir connection, and connection D to the regulating portion (single or duplex) connecting at D in Figs. 16 and 17. In operation with either a single or duplex regulating portion, as soon as the pressure in the brake pipe is great enough to over- 138 TEE AIB BRAKE. -73 o to •-=: »^ I I I I H t- O Tti CO (« Oi O CO tJH <^ I—I C'^S'^ 5r! £ 03 o . (D I rH Ni _..k«. *~~A ^, MJ