before mixing new product with it. Drain water from the tank before starting transfer. Gage tank again and
record the data. Make sure that the receiving container and tank car are properly grounded and vented.
Tank Car Inspection. Compare car number and seal number with numbers on shipping papers to see that
the car to be unloaded is at the right destination. Examine the seals and locks carefully for evidence of
tampering. If cars arrive with broken seals or locks, notify the proper authority. If it is absolutely necessary
that the car be released because of a shortage of tank cars, transfer the contents into a separate container,
but do not use the product for any purpose until tested samples have been approved. Shortage of product
should be made a matter of record. Pry seals loose and remove the dome cover. In hot weather extremely
high pressures may develop in tank cars if the safety valve is not functioning. When time permits, relieve
pressure by permitting the car to cool overnight. If pressure is released by venting, large quantities of
product are lost through vaporization creating potential fire hazard. Inspect the tank car for leaks through the
shell and bottom outlet. If the car shows evidence of leaking, schedule the car for immediate unloading.
Place containers in position to catch leaking product.
Sampling and Gaging Tank Car. Gage and sample the contents of the tank car, and examine the sample
for appearance and color. Take temperature of the product, correct the volume to 60 degrees Fahrenheit,
and record the data. Remove any water present in the tank by draining water slowly through the bottom
outlet. If water is removed, gage the contents again, correct volume to 60 degrees Fahrenheit, and record
data. Examine a sample of the product visually to make sure that the product is of proper grade. Fuel
having a cloudy or decidedly "off color" appearance should be suspected of having some contamination.
Any questionable product should be thoroughly tested to make sure that it meets specifications before it is
Tank Car Valve Inspection. If the car is to be unloaded through the bottom outlet; make sure that the outlet
chamber is in good condition and that the outlet valve is operating properly. The valve may become
inoperable in cold weather because water in the tank is likely to settle and freeze around the outlet valve. To
free frozen valves, apply steam jet, hot water, or hot cloths to the outlet chamber. When authorized a hot air
duct tent heater, or a slave kit may be used by trained personnel to thaw the outlet. If time permits, allow the
valve to thaw during the warm part of the day.
Unloading Tank Car.
To unload a tank car through the bottom outlet, locate the pump at least 50 feet from tank car and
ground the pump.
Make sure that the outlet valve is seated properly.
Place a suitable drainage tub under the bottom outlet.
The tub should remain under the outlet until the transfer operation is completed.
Loosen the bottom outlet cap one or two turns to permit product trapped in the outlet chamber to drain
out around the threads into the tub. (If flow from the outlet does not slow down after approximately 15
minutes, attempt to seat the valve properly.
If the valve cannot be seated, unload the tank car through the dome. Connect the pump suction line to
the tank car outlet.
Connect the pump discharge line to the inlet of the receiving container.
Dispose of drainage collected in the drainage tub and again place the tub in position to catch any further
Place the dome cover over the manhole in such a way that air can enter the tank as product is unloaded.
Place a block of wood under the edge of a hinged dome cover to ensure ample venting.
When all connections are secure, open the bottom outlet valve.
Open the necessary valves in the line to permit the free flow of product, and start the pump.
As product starts to flow through the line observe all connections to make sure that there are no leaks.
If leaks are apparent, stop the pump and make necessary repairs or adjustments to stop the leaks before
When all product has been unloaded from the tank, wait until the pump drains the suction line, and then
shut down the pump.
Close the inlet valve of the receiving container immediately after shutting down the pump so that product
will not drain back into the line.
Dome Unloading. To unload the tank car through the dome locate the pump at least 50 feet from the
tank car and ground the pump. Place a drainage tub under the bottom outlet to catch any drainage. Insert