SALCO PRODUCTS, INC. PRESSURE RELIEF VALVE STORAGE, INSTALLATION, OPERATING, MAINTENANCE/TESTING, AND INSPECTION INSTRUCTIONS

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1 STORAGE INSTRUCTIONS Until it is time to install a new or reconditioned valve on the car, the valve must be kept in its original packaging in order to protect it from dirt and damage. INSTALLATION INSTRUCTIONS 1. DO NOT PAINT VALVE! This may interfere with the valve s performance. 2. Before beginning any work on the car, ensure that you follow your company s and all applicable safety standards. 3. When no valve is present on the pressure relief valve opening, always protect the opening from dirt, debris, damage, etc. by placing a cover or plug over the opening and flange mating surface. 4. If stud threads are showing wear, contain burrs or are dirty, gauge the threads and replace as necessary according to the AAR Manual of Standards and Recommended Practices or your company s practices. 5. Each time a new or reconditioned valve is installed, a new gasket must be used. Carefully remove and throw away the existing gasket. 6. Before installation of the valve, examine the groove and/or gasket surface for nicks or burrs. Ensure the gasket surface is clean. It is important for the sealing of the valve that there be no interference. 7. When ready to install the valve, remove the new or reconditioned valve from its packaging and inspect the sealing surfaces for nicks or burrs. It is important for the sealing of the valve that there be no interferences. To remove nicks and burrs, the AAR does allow machining of the flat face gasket surface or tongue by a trained specialist. However, AAR specified tolerances must not be exceeded. 8. Remove the protective covering or plug from the pressure relief valve opening and install the new gasket. Carefully lower the valve onto the gasket orienting the valve bolt holes to align with the stud holes. 9. Tighten the stud nuts uniformly, alternating across from one (1) to three (3) and then two (2) to four (4). It is important to compress the gasket evenly and to not over tighten one side or the other or the gasket will not seal. 10. Torque the stud nuts to a value recommended by your engineering department. 11. Inspect the bolted connection for leaks in a method compliant with your company procedures. OPERATING INSTRUCTIONS 1. It is your responsibility to operate this valve in accordance with each applicable federal regulation and your company s instructions and procedures. 2. This valve is a spring-loaded device designed to automatically open when there is an overpressurization in the tank. The valve s internal components should never be adjusted when on a tank car. Any adjustments to the set pressure must be done while the valve is on a pressure test stand. See Maintenance/Testing Instructions. TOMBALL, TEXAS (281) of 5

2 MAINTENANCE/TESTING INSTRUCTIONS Intervals The Department of Transportation (DOT) and the Association of American Railroads (AAR) have established minimum retesting intervals for pressure relief valves. It is important that each end user of a pressure relief valve establish their own procedures and testing intervals for valves used in their particular service. The DOT and AAR regulations should be viewed as a minimum and experience with your own service conditions should be used to establish specific procedures concerning your equipment. New Valves Valves that are bought new from Salco Products, Inc. and are still in the original packaging are ready to go into service without any further testing as long as they have not been in storage for longer than six (6) months. Valves that have been in storage for longer than six (6) months should be retested following the procedure outlined below. Retesting 1. A valve that needs to be retested shall first be visually inspected for product damage, and for missing, bent, or broken parts. Damaged parts must be replaced with only Salco OEM parts. Contact Salco for replacement parts. Repair work must be limited to the AAR s Manual of Standards and Recommended Practices, M-1002, Specifications for Tank Cars, Appendix A, Section Disassembly (Refer to Figure 1.) Caution: Internal spring may be under pressure. Exercise caution when removing the Spring Holder Cut the cable seal running from the Cap Cable Seal Hole to the Flange Cable Ring To disassemble the valve, first remove the Cap using a 9/16 allen wrench Remove the Retainer using the Retainer Removal Tool (sold separately) Before removing the Spring Holder, mark the interior threads of the body to help locate the current location of the Spring Holder. This will help during the reassembly of the valve. In lieu of making a mark, a measurement from a reference location can be made to accomplish the same objective Since it is possible that the spring is under preload, care must be taken when removing the Spring Holder. Using the Spring Holder Removal Tool (sold separately), carefully remove the Spring Holder while ensuring that the pressure on the threads is equalized. Uneven pressure on either side of the Spring Holder may cause galling of the threads Remove the Washer, Spring and Stem Assembly from the Body Visually inspect the seating area inside the Body, the Stem Assembly, Washer, Spring, and Spring Holder for visual signs of damage and wear. TOMBALL, TEXAS (281) of 5

3 2.08 In accordance with the AAR s Manual of Standards and Recommended Practices, M- 1002, Specification for Tank Cars, Appendix D, Section 4.3, elastomeric materials used for gaskets or gasket seals must be replaced each time a valve is retested or taken apart. Replace the O-ring in the Stem by removing the Screw, Lock washers and Seal Holder. Use an O-ring of a compatible material with the lading. Place a small amount of a lubricant approved for service on the O-ring and reinstall it in the Stem Assembly. The Lock washers and Screw should not be reused. Replace these each time in-kind and torque to 5-6 ft-lbs. 3. Reassembly (Refer to Figure 1.) 3.01 Place the Stem Assembly with the new O-ring, Lock washers and Screw in the Body of the valve making sure the O-ring is properly seated by turning the Stem by hand Reinstall the Spring, Washer and Spring Holder in the Body using the Spring Holder Removal Tool (sold separately). Ensure that even pressure exists on both sides of the Spring Holder so that galling does not occur. Return the Spring Holder to the position that was marked/measured during the disassembly Reinstall the Retainer in the Body using the Retainer Removal Tool (sold separately) Reinstall the Cap tool tight using a 9/16 allen wrench. 4. All retesting of valves or troubleshooting of leaking valves must take place off the car and on a pressure test stand (except for leaks occurring between the valve flange and tank.) 5. Definitions (as found in the AAR s Manual of Standards and Recommended Practices, M- 1002, Specifications for Tank Cars, Appendix A): Start-to-Discharge (STD) the pressure, measured at the valve inlet, at which there is a measurable lift of the closure device on a pressure relief valve or at which discharge becomes continuous as determined by seeing, feeling, or hearing. Start-to-Leak Pressure the pressure, measured at the valve inlet of the pressure relief valve, at which the relieved fluid is first detected at the downstream side of the seat. Vapor-Tight-Pressure (VTP) the pressure, measured at the valve inlet after closing, at which no further fluid flow is detected at the downstream side of the seat of a pressure relief valve. 6. The STD pressure of each valve is indicated on the nameplate. The purpose of retesting a valve is to ensure that the valve maintains the proper STD pressure setting and that the VTP is above the minimum required. The tolerances of these values are stated in the AAR s Manual of Standards and Recommended Practices, M-1002, Specifications for Tank Cars, Appendix D. 7. The test must be performed on an appropriate pressure test stand using an appropriate gasket. Install the flange on the stand and tighten the bolts in alternating fashion (1, 3, 2, 4). 8. Using a certified test gauge per the AAR s Manual of Standards and Recommended Practices, M-1002, Specifications for Tank Cars, Appendix D, 4.5, apply the specified test pressure with a suitable gas. 9. Note the pressure at which the valve starts to discharge (STD). 10. Reduce the pressure slowly and note the pressure when the valve is bubble-tight (VTP). 11. The spring tension may need to be reset if the valve does not function within the prescribed pressure ranges as defined in the AAR s Manual of Standards and Recommended Practices, M- TOMBALL, TEXAS (281) of 5

4 1002, Specifications for Tank Cars, Appendix D, Table D2, which shall also match the nameplate on the valve. 12. Resetting the Tension on the Spring If the desired STD pressure is above where the valve starts to discharge, the spring is not under enough load and the Spring Holder and Retainer need to be tightened against the spring If the desired STD pressure is below where the valve starts to discharge, the spring is under too much load and the Spring Holder and the Retainer need to be backed off Carefully make the necessary adjustments to the Spring Holder and Retainer by using the Retainer Removal and Spring Holder Removal Tools (sold separately). Ensure that even pressure is always maintained on both sides of the Spring Holder when making adjustments so that galling does not occur in the threads The amount of adjustment should be in proportion to the difference between the set point and the actual reading. As the gap between the set point and the actual reading reduce, the amount of adjustment made should be reduced proportionally so that gradual improvements are made. 13. Repeat testing of the valve and resetting of the spring until the results from testing are consistently in the proper range. 14. After completion of the retesting, place protective coverings over the flange surface of the valve to protect it from damage and replace the cable seal by looping it through the Cap Cable Seal Hole and Flange Cable Ring. 15. Follow your company s procedures and DOT s regulations when completing all necessary documentation of the results of the retest. 16. Place the valve in protective packaging and store it in a clean, dry place until it is applied to a car. INSPECTION 1. At each loading and unloading of the tank car, it is appropriate to visually inspect the pressure relief valve for visual indications of damage, debris, corrosion, and cracks. 2. Should any signs of deterioration of the valve be present at any time, the valve should be removed from the car and subjected to a full inspection and retest. TOMBALL, TEXAS (281) of 5

5 NO. 1 PART NAME CAP 2 RETAINER 3 4 SPRING HOLDER WASHER SPRING STEM 7 O-RING 8 SCREW 9 SEAL HOLDER 10 LOCK WASHER 11 BODY 12 CAP CABLE SEAL HOLE FLANGE CABLE RING NAMEPLATE 14 TONGUE AND GROOVE FLANGE OPTIONAL FIGURE 1 TOMBALL, TEXAS (281) of 5