Do's & Don'ts Poster for General Service Cars
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DO’S Do’s and Dont’s of General Service Tank Car Handling IT IS the Shipper’S reSponSibilitY to bottom unloading. This is essentially a plug type valve mounted to nar.aar.com To ensure safe operating procedures, ENSURE THAT NO a saddle on the bottom of the tank that is controlled at the top of commoDitY IS leAKinG follow safety rules, practice proper the tank via a rod attachment. When the valve cover is removed, From ANY component it may be inverted and used as a tool to operate the valve. maintenance and use common sense. OR THE TANK ITSELF DO - verify car stencilling information such as car number, BEFORE SHIPPING A CAR. specification, HM201 qualification, dates, tank, contents, etc. The vapor valve is typically a ball type valve. It is usually attached 1 2 General service tank cars are equipped to the top of the fittings coverplate using flanged or screwed connections. Since it does not extend into the liquid, it will only with various top and bottom fittings to expel vapor when opened. 3 Do’s AND Don’ts allow loading, unloading, gauging and 4 testing operations. For additional During a top unloading process, the unloading line is attached to 5 OF GENERAL SERVICE the liquid valve, and an air or gas line is attached to the vapor 6 information, read AAR BOE Pamphlet 34, valve. Pressure is applied to the tank by forcing air or an inert gas 8 DO - vent the interior tank pressure DO - use the stuffing box cover TaNK CAR HANDLING before loosening manway cover or a square drive tool to operate the into the vapor space of the tank through the vapor valve such that bolts and hold down before loading/ top operated bottom outlet valve rod. your company’s instructions, applicable 7 the tank contents are forced through the eduction tube. unloading the tank (except for pressure loadings). © 2009 GATX government regulations, and AAR’s www.gatxrail.com NAR web site at nar.aar.com. During a bottom unloading process, the manway cover or vapor valve is opened to vent the tank. The pipe plug on the BOV cap is removed to ensure the valve is not leaking. The cap is then 1 MANWAY 5 2” or 3” EDUCTION VALVE / PIPE 8 SAFETY VAlveS & VENTS removed, and the unloading hose is attached to the outlet nozzle 2 GAUGE BAR 6 SAMPLE LINE The purpose of a safety valve or vent is to prevent the tank pressure of the BOV. When the BOV is opened, gravity allows product to flow 3 THERMOWELL 7 1” or 2” AIR CONNECTION VALVE from exceeding a specified limit. A SAFETY VALVE re-closes after to a pump which then moves the commodity to its destination. 4 VACUUM RELIEF VALVE 8 SAFETY VALVE DO - secure valves and fittings DO - release the handbrake before NOTICE: This poster is offered as a guide to encourage properly prior to release of a loaded moving a car. this limit is exceeded and excess tank pressure has been relieved. or empty car. safe operating procedures and should not be construed as A SAFETY VENT does not re-close and requires that a frangible Most valves have self-lubricating Teflon packings and Teflon seats. a complete maintenance manual or operating instructions. disk (rupture disk) be replaced every time a pressure relief event These guidelines are contingent on following established Therefore, no special maintenance is necessary. They are designed to occurs. The pressure setting on general service safety valves and Unloading Arrangements safety rules and practicing proper maintenance. They assume be closed only hand tight. Wrenches pry-bars or other mechanical vents is165 psi maximum. Dome Cover a basic understanding of railcar operation and are not intended devices may potentially damage these valves. Safety Vent/Valve to replace existing company standards and procedures. Stuffing Box Cover Safety valves and vents are typically mounted on the fittings 3 THERMOMETER WELL DO - use steam to free a frozen DO - use proper tools to unfasten/ nozzle cover plate or on a separate tank nozzle specifically for A thermowell is a long tube mounted to the fittings coverplate Figure 1 Valve Rod outlet valve. fasten the manway cover hold down the safety valve. Safety vents may be mounted on the manway bolts. that extends into the tank and is typically filled with antifreeze. TOP OPERATED BOTTOM Operating OUTLET VALVE Screw cover plate as well. Post Flange A screwed cap is removed from the top of the thermowell, and a Outlet Valve Remove the stuffing box cover; invert the long thermometer is inserted into the thermowell to measure the Outlet Nozzle stuffing box cover and fit onto the valve rod 1 Outlet Cap DON’TS MANWAY AND FILL HOLE NOZZLES temperature of the antifreeze. The temperature of the antifreeze is for use as a valve operating wheel. Plug A manway consists of a flanged nozzle located at the top of the representative of the temperature of the tank contents. GATX RAILCAR tank. It is equipped with either a bolted cover or a hinged and bolted REGIONAL MAINTENANCE cover with a gasket to provide a seal in the closed position. Hinged VACUUM RELIEF VAlveS 4 Figure 2 RAIL NetworK manway covers are typically sealed with eye-bolts that rotate into Vacuum relief valves are typically located on the fittings position for tightening. BOTTOM OPERATED arrangement nozzle. Their purpose is to prevent implosion of a BALL VAlve OFFICES USA sealed tank in the event that residual vapor cools and condenses Operate from outside Colton, CA MOOSE JAW, SASKATCHEWAN USA A fill hole is configured similar to a manway. However, it is typically tank at ground level. DON’T - poke ball of bottom DON’T - ship a car before removing 909.825.3043 306.692.7070 into a liquid, thereby resulting in negative pressure inside the tank. spilled commodity from the exterior. Remove lock pin and seal. outlet ball valve to free it when HEADQUARTERS much smaller and is used exclusively as a loading nozzle for some frozen, as this will damage the ball Opening of ball valve requires a 90˚ Chicago, IL WAYCROSS, GA RED DEER, ALBERTA and cause it to leak. 312.621.6200 912.287.8160 403.347.6700 commodities. HEATER COILS movement of valve handle. Some tank cars are equipped with heater coil systems for the SAN FRANCISCO HEARNE, TX Fast Track 415.955.3200 979.279.3481 Service Centers and A gauge bar is typically located on the inner edge of the manway purpose of heating the tank contents to facilitate unloading. Heater coils may be located on the interior or exterior of the tank. HOUSTON CANADA Mobile Service Units nozzle. It serves as one means of verifying the required outage WARNING 713.752.0393 Steam is the typical heating medium, although hot oil is sometimes U.S. space in the tank. It consists of a scale that indicates the fill level What to do if you think your product is frozen: SARNIA, ONTARIO 1.800.500.6839 AtlANTA 519.344.1130 of the tank. used to achieve higher heating temperatures. In some cases, 678.624.9700 CANADA auxiliary heating systems are fed by the heater coil system to MONTREAL, QUEBEC UNLOADING: DO’s DON’T - use a pipe wrench to DON’T - use an extension tool cheater 1.800.806.2489 CANADA 514.648.3801 FITTINGS NOZZLE AND AttACHMENTS allow localized heating of valves and fittings. 1. Ready car for unloading. operate stuffing-box bottom outlet to try to force open a seized or frozen valve rod, as this will damage the rod. bottom outlet ball valve, as this will MONTREAL A fittings nozzle consists of a flanged nozzle with a bolted cover 2. Open manway cover to prevent pressure build-up as product thaws. twist the valve stem and render. 514.931.7343 plate and gasket. A number of devices are mounted to the coverplate. Interior heater coils are supported by brackets mounted to the 3. Connect steam hose to heater coils and apply steam gradually to prevent damage from sudden thermal shock. MEXICO Mounting connections to the cover plate may be either flanged and bottom interior surface of the tank. Interior heater coils offer more 4. Regularly monitor lading temperature. MEXICO CITY bolted or screwed. efficient heating of the tank. However, the use of interior coils has 5. Inspect outlet unloading connections for freezing damage. If no 011.52.55.5.283.1201 diminished significantly due to the potential for product damage or cracks are evident, apply steam to outlet connections immediately prior to commencement of unloading. The liquid valve is typically a ball type valve that is used for both contamination and extensive maintenance. 6. Commence unloading. loading and top unloading of the tank. For top unloading, it is 7. Blow out heater coils with dry air to ensure no water is left in coils connected to a pipe mounted to the fittings nozzle coverplate that Exterior heater coils are located on the exterior surface of the tank which could freeze and damage them. Leave coil caps off. DON’T - let foreign objects drop into DON’T - use an extension tool to the tank, as this will clog the bottom tighten cover hold down bolts, as this extends to within 2” of the inside bottom of the tank. These pipes in a serpentine pattern and utilize a low profile, oval shaped coil outlet valve or eduction pipe. will bend the bolts and strip UNLOADING: DON’Ts the threads. are called eduction pipes. Eduction pipes may be of the stiff or section. The heating medium is fed to the coil system via threaded 1.