2.2 Procedure
1. Prior to removing any valve or fitting from a tank, ensure that the internal
pressure is at atmospheric and that personnel exposure to hazardous
chemicals is eliminated.
2. When the securement bolts have been removed from the mounting flange,
remove the valve, and discard the old flange gasket.
3. The flange mating surface should be free from gouges, scrapes, and
excessive corrosion. If the valve has a flat mating surface, clean the mating
surface using a wire brush if scale, rust, adhesive, or dirt are evident. With
a tongue and groove mating surface, ensure that while removing the old
gasket no damage is done to the bottom of the groove. Any burrs that exist,
radial gouges and debris should be removed.
4. A new pressure relief valve should be kept in its original packaging to
prevent damage to the valve or its components.
5. A test certificate should be available to verify the test date of the valve, if
the last known test date was within six months, the valve can be installed
without retesting or requalifying.
6. Place a new gasket on the tank mounting flange. Kelso Technologies does
not supply the flange gasket, refer to your company’s internal
documentation/procedures for the correct gasket type and material. Gasket
material should be compatible with the chemical being shipped. Inspect the
valve mating flange for defects as described in Paragraph 3 above. Install
the valve on the mounting flange and secure using bolts. The bolts should
be tightened to a prescribed torque of 100-to-180-foot pounds, depending
on the gasket being used. Our suggested value is only to be used in the
event your company does not have a procedure for this.
7. Once the pressure relief valve has been secured to the car, a suitable leak
test should be performed to ensure the flange mating surfaces are pressure
tight.
2.3 Leak Inspection
All newly installed valves must be tested under pressure to confirm that no leaks
are present.
WARNING: Loose nuts, improper tongue seating in the flange, damaged and
wrong size gaskets can result in leaks at the valve mating surfaces.
2.4 Valve Operation
Operation of all valves must conform to all applicable TC, AAR, DOT, and other
governmental bodies.
Kelso valves are spring loaded by a constant force set of springs and there are
no provisions for manual activation. Valves are activated over pressurization,
even on the rail tank car.
