D-1-A TRIPLE VALVE, PC. NO

Transcription

1 D-1-A TRIPLE VALVE, PC. NO MARCH, 1985 Supersedes issue dated July, 1984 NOTE: The following description and operation is based on this device and its components being new or this device and its components having been repaired, tested, installed and maintained in accordance with instructions issued by this and any other applicable Wabtec Corporation publications. WARNING: At the time any part is replaced in this device, the operation of the complete device must pass a series of tests prescribed in the latest issue of the applicable Wabtec Test Specification. At the time this device is applied to the brake equipment arrangement, a stationary vehicle test must be made to insure that this device functions properly in the total brake equipment arrangement. (Consult your local Wabtec Representative for identity of the test specification, with latest revision date, that covers this device.) IMPORTANT: Only Wabtec supplied parts are to be used in the repair of this device in order to obtain satisfactory operation. Commercially available non- O.E.M. parts are unacceptable. NOTE: The part numbers and their associated descriptions are the property of Wabtec Corporation and may not be replicated in any manner or form without the prior sole written consent of an Officer of Wabtec Corporation WABCO Locomotive Products. A Wabtec Company. All rights reserved March, 1985 Page 1 of 6

2 the diaphragm piston assembly (13) is connected to port 5. IMPORTANT: When the D-1-A Triple Valve is used on a car which is being hauled by a locomotive, the device which is used to cut-off air flow from the supply reservoir to port 5 of the pipe bracket MUST BE IN THE OPEN position so that air flow to port 5 of the Triple Valve is unrestricted. CHARGING When brake pipe air is admitted to chamber A, the diaphragm piston (13) moves to release position. This permits spring (21) to seat the check valve (22) closing the supply reservoir passage. APPLICATION This diagrammatic representation is for functional analysis only. It is not to be used as an actual physical representation of portion or pipe bracket configurations. 1.0 DESCRIPTION Figure 1 - Diagrammatic View The D-1-A Triple Valve is a diaphragm operated device consisting of a D-1-A Triple Valve Portion and a Pipe Bracket Portion. The Triple Valve Portion is mounted on the Pipe Bracket in such a way that it can be removed for service or maintenance without disturbing the piping of the vehicle. All pipe connections are made to the Pipe Bracket Portion. NOTE: The D-1-A Triple Valve is designed for use in special airbrake equipment arrangements on rail vehicles. These vehicles are to be operated in train consists which do not exceed 1200 feet in total train length. The air pressure in these special equipment arrangements MUST NOT exceed 110 psig. The device is used to provide a method of car braking if the cars are being pulled by a locomotive. Consult your Wabtec Corporation Representative for installation procedures for specific applications. 2.0 OPERATION (FIGURE 2) The D-1-A Triple Valve functions in response to an increase or decrease in pressure in port 1. When air flow in the supply reservoir port 5 to the pipe bracket is cut-off, such as by the closing of a cut-out cock or another device and when air pressure is present in the brake pipe port 1 and chamber A, the Triple Valve is pneumatically locked in the release position. Chamber B on the upper side of When a reduction in brake pipe pressure occurs in port 1 and chamber A below the diaphragm piston assembly (13), the valve functions to admit air into the brake cylinder port 3. The pressure reduction in chamber A permits supply reservoir air in chamber B to move piston (13) to service position. In this position the piston stem seats on the check valve (22) to cut off the brake unit exhaust and unseats the check valve (22) to connect supply reservoir air to the brake unit port 3. Supply reservoir air flows to port 3 until the pressure in the supply reservoir falls to approximately that in the brake pipe, when the brake pipe air and spring (14) move the piston to lap position. Spring (21) seats check valve (22) closing the connection between the supply reservoir and port 3. This stops further flow of supply reservoir air. Supply reservoir air pressure is then practically equal to that in the brake pipe and prevents movement of the piston toward release position. The piston will remain balanced in lap with the brake unit pressure held constant until the brake pipe pressure is either reduced further to increase port 3 pressure, or increased in order to release the brake. If a further reduction in brake pressure port 1 is made after the valve is in service lap position, the pressure on the brake pipe side of piston (13) drops below that on the supply reservoir side and causes the piston to move as described for the first service application of the brake. If the brake pipe reduction is continued, the supply reservoir pressure will continue to fall and the port 3 pressure will rise until these two become equal. NOTE: Reduction of brake pipe pressure beyond this equalization pressure does not increase port 3 pressure. This is Page 2 of 6 March, 1985

3 a needless waste of air and should not be permitted. RELEASE To release the valve and recharge the supply reservoir (port 5) air is directed via trainline piping to the brake pipe (port 1) and is directed to chamber A below the diaphragm piston assembly (13). The diaphragm piston assembly (13) moves and lifts the piston stem off its seat permitting the force of spring (21) to position the check valve (22) to allow brake unit air in line (3) to be exhausted through the piston stem to atmosphere at port EX. NOTE: It is important to remember the sequence of operation when a locomotive is coupled to tow a car or train containing this valve in addition to standard brake equipment for transit operation. If in special applications the cars have been running singly or M.U. (multiple unit), the supply reservoir is charged to M.R. (main reservoir) pressure. Therefore, when port 5 is opened, supply reservoir pressure being considerably higher than brake pipe, the brake unit pressure will build up to a higher than normal value. When the brake pipe pressure in chamber A moves the diaphragmpiston assembly to release position a release of the car brakes will occur. 3.0 MAINTENANCE SCHEDULE IMPORTANT: The D-1-A Triple Valve Portion should be removed from the equipment arrangement, taken to the shop, be completely disassembled, the parts cleaned, inspected, lubricated, assembled, and the valve portion tested according to the following application schedule or more frequently if service conditions so indicate. SPECIAL FREQUENCY - TYPE OF APPLICATION AT LEAST ONCE EVERY Passenger (Interstate) Transit 36 Months 24 Months 4.0 PARTS CATALOG INFORMATION Refer to the Wabtec Corporation Parts Catalog , S.2 when ordering replacement parts. NOTE: The reference numbers used in this publication and those used in the parts catalog may differ. Check the descriptive parts name to be sure that the desired part is ordered. 5.0 SAFETY PROCEDURES AND WARNINGS Regular shop safety procedures are to be followed when working on the D-1-A Triple Valve. The work area is to be clean. WARNING The following statements of warning apply all or in part wherever the symbol appears in the maintenance procedures. Failure to observe these precautions may result in serious injury to those performing the work and/or bystanders.! The use of an air jet, which must be less than 30 p.s.i.g., to blow parts clean or to blow them dry after being cleaned with a solvent will cause particles of dirt and/or droplets of the cleaning solvent to be airborne. Wire brushing may also cause particles of dirt, rust, and scale to become airborne. These conditions may cause skin and/or eye irritation.! When using an air jet, do not direct it toward another person. Improper use of air jet could result in bodily injury.! Personal eye protection must be worn when performing any work on this device or its components parts to avoid any possible injury to the eyes.! The use of solvents as cleaning agents and the use of lubricants can involve health and/or safety hazards. The manufacturers of the solvents and lubricants should be contacted for safety data (such as OSHA Form OSHA-20 or its equivalent). The recommended precautions and procedures of the manufacturers should be followed.! When performing any test or work on devices or equipment while they are on the vehicle (on car test, etc.) special precautions must be taken to insure that vehicle movement will not occur which could result in injury to personnel and/or damage to equipment.! Assembly may be under a spring load. Exercise caution during disassembly so that no parts Fly Out and cause bodily injury.! All air supply and/or electric current to this device and/or to any components part must be cut-off before this device and/or any component part is removed from the equipment arrangement. March, 1985 Page 3 of 6

4 ! Bottled up air under pressure (even though air supply is cut-off) may cause gaskets and/or particles of dirt to become airborne and an increase in sound level when this device and/or any component part is removed from the equipment arrangement.! Personal eye and ear protection must be worn and care taken to avoid possible injury when performing any work on this device and/or component part.! To prevent receiving electrical shock when performing electrical tests, hands must be clear of electrical components, contacts and housing and there must be no bodily contact with the work bench. Failure to heed this warning could result in severe injury or death. 6.0 CLEANING SOLVENT & LUBRICANT 6.1 The solvent used for cleaning the metal parts of the D- 1-A Triple Valve must be an aliphatic organic solution, such as mineral spirits or naphtha, that will dissolve oil or grease and that will permit all parts to be thoroughly cleaned without abrasion. 6.2 No. 2 Silicone Grease, Wabtec Corporation Specification M is required for the lubrication of o-rings, o- ring grooves and the bearing surfaces of the bushings into which the o-ring assemblies are installed. 7.0 REMOVAL & INSTALLATION OF D-1-A TRIPLE VALVE PORTION ON CAR (FIGURE 3) 7.1 Repair person should have a cleaned or NEW strainer (5), a retaining ring (4), a NEW mounting gasket (6) and a NEW or repaired and tested D-1-A Triple Valve Portion, Pc.No Observe ALL safety procedures and WARNINGS of Section Chock vehicle wheels to prevent movement and place WARNING placards stating that work is being performed on and about the vehicle. 7.4 Clean all free dirt from the exterior surfaces and remove the Triple Valve Portion from the pipe bracket by first removing the four 1 /2" hex nuts, (hex nuts are not illustrated). 7.5 Remove and SCRAP the pipe bracket gasket (6). 7.6 Remove the retaining ring (4) which secures the strainer (5) in the pipe bracket and then remove the strainer (5). 7.7 Visually inspect the air ports and mounting surface of the pipe bracket to be sure that they are clean. If necessary, blow clean, using a low pressure jet of clean, dry air. Exercise care so that NO dirt is blown back into the passages of the pipe bracket. 7.8 Install a NEW or cleaned strainer (5) in place in the pipe bracket and secure it in place with the retaining ring (4). 7.9 Place a NEW pipe bracket gasket (6) in place on the pipe bracket, then install a NEW or repaired and tested Triple Valve Portion and secure it in place using four 1 /2" hex nuts. The hex nuts are not illustrated IMPORTANT: Whenever the D-1-A Triple Valve Portion is removed from the equipment arrangement for any reason, and it is reinstalled or replaced with a NEW or repaired and tested portion, a stationary vehicle air brake test MUST BE made to be sure that the Portion functions properly in the brake equipment arrangement Remove all WARNING placards and wheel chocks before attempting to move vehicle. 8.0 "IN-SHOP" MAINTENANCE PROCEDURES (FIGURE 2) 8.1 DISASSEMBLY Check mounting face of the body (24) to be sure that mounting gasket (6) is not adhering to metal service. If not removed, remove and SCRAP the gasket (6) Remove the cap nut (20), then remove the check valve spring (21), and check valve (22). SCRAP the check valve (22) Remove the four cap screws (7) which secure the cover (8) to the valve body (24), then remove the cover (8), ring gasket (9) and diaphragm piston assembly (10, 11, 12, 13, 15, 16, 17, 18, 19). SCRAP the gasket (9) Remove the piston return spring (14) Disassemble the diaphragm piston assembly by removing the hex nut (10), then remove the diaphragm follower (11), diaphragm (12) and spool valve piston (17) from the piston head (13). SCRAP the diaphragm (12). Page 4 of 6 March, 1985

5 Figure 2 - Assembly View Remove and SCRAP the four o-rings (15, 16) from the stem of spool valve piston (17) Remove and SCRAP the two o-rings (18) from the outer undercut of the piston bush Remove and SCRAP the wrap around felt strainer (19). 8.2 CLEANING & INSPECTING O-RINGS, GASKETS, DIAPHRAGM, FELT STRAINER & CHECK VALVE ALL o-rings, gaskets, the diaphragm, felt strainer and the check valve are to be SCRAPPED and replaced with NEW Wabtec Corporation Parts METAL PARTS Wash all of the metal parts in the cleaning solvent described in Section Be sure that the interior and exterior surfaces of the body are cleaned. Use a lint-free cloth or rag which has been saturated with the prescribed cleaning solvent to clean the body The springs may be wire brushed to assist in removal of any dirt, rust or scale. March, 1985 Page 5 of 6

6 After the parts are cleaned, they are to be blown completely dry using a low pressure jet of clean, dry air Inspect the springs. Replace any spring that is rusted, pitted, distorted or that has taken a permanent set Inspect the remaining parts. Replace any part that is cracked, cut, broken, excessively worn, damaged in any way or that is in such a condition that may result in the unsatisfactory operation of the D-1-A Triple Valve Portion. 8.3 ASSEMBLY Carefully wrap a NEW felt strainer (19) around the outer piston bush undercut of the body (24) and secure it in place using two NEW 7 /8" O.D. o-rings (18) Lubricate the surfaces of a NEW 5 /8" O.D. o-ring (15) and three NEW 3 /8" O.D. o-rings (16) with No. 2 Silicone Grease, Wabtec Corporation Specification M Also fill the o-ring grooves of the stem of the spool valve piston (17) and lubricate the bearing surfaces of the piston bush in the body (24) with the lubricant Install a NEW lubricated 5 /8" O.D. o-ring (15) in its groove on the spool valve piston (17). Remove any excess lubricant by wiping with a clean, dry lint-free cloth or rag Install the piston head (13), with diaphragm groove up, a NEW diaphragm (12) and the diaphragm follower (11) on the spool valve piston (17) and secure the parts in place using the 1 /2" hex nut (10). Exercise care during assembly to be sure that the diaphragm is not crimped or cracked Install the three NEW lubricated 3 /8" O.D. o-rings (16) in their grooves on the spool valve piston (17). Remove any excess lubricant by wiping with a clean, dry, lint-free cloth Place the piston return spring (14) in the cavity of the body (24) Install the diaphragm piston assembly (10, 11, 12, 13, 15, 16, 17, 18, 19) into the bush in the body (24) Install a NEW ring gasket (9) into its recess in the cover mounting face of the body (24) Properly position the bead of the diaphragm (12) in its groove in the cover mounting face of the body (24) and then carefully install the cover (8) in position on the body (24) Secure the cover (8) in place on the body (24) using the four 3 /8" x 1 1 /4" cap screws (7). Equally tighten the cap screws being careful not to crimp or cut the diaphragm Install a NEW check valve (22) in place in the body (24) Install the check valve spring (21) into the cavity of the cap nut (20), and then install the assembly into the body (24) so that the spring (14) seats in the recess of the check valve (22). Tighten the nut securely. 9.0 TESTING & ADDITIONAL INFORMATION 9.1 After the D-1-A Triple Valve Portion has been assembled, BUT BEFORE it is returned to service, it MUST PASS a series of tests following the procedures of the current issue of the Wabtec Corporation Test Specification T-2888-O. 9.2 IMPORTANT: Whenever the D-1-A Triple Valve Portion is removed from the equipment arrangement for any reason, and it is re-installed or replaced with a NEW or repaired and tested Portion a NEW mounting gasket (6) MUST BE used. 9.3 IMPORTANT: Whenever the D-1-A Triple Valve Portion or any component part of the D-1-A Triple Valve is removed from the equipment arrangement for any reason and it is reinstalled or replaced with a NEW or repaired and tested Portion or component part, a stationary vehicle air brake test MUST BE made to be sure that the D-1-A Triple Valve functions properly in the brake equipment arrangement. 9.4 Consult your Wabtec Corporation Representative if additional information is required. WABCO Locomotive Products 1001 Air Brake Avenue Wilmerding, PA (412) Fax (412) Page 6 of 6 March, 1985