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- how much liquid can one put in a propane tank without the tank exploding?

The Propane industry mandates that a tank not be filled more than 80%. The question I have is this: how do I calculate the limit of liquid propane in a standard 3800 liter tank given a 30 degree rise in temperature (from 273 K to 303 K) such that it will not rupture the tank? For example, can I exceed the "80% fill rule" and put in 95% without fear of compromising the tank?

The tank is rated at 250 psi with a 4:1 safety factor. The pressure relief valve is assumed stuck shut. From what I've found on the web, the thermal expansion of liquid propane is 0.003 per degree K. Thus, if I understand correctly, 30 degrees should result in a 9% increase. If the tank was initially filled to 92%, then the liquid should expand to fill the tank, and, presumably, the expanding liquid will subsequently exceed the 1000 psi mark and burst the tank. Or, will the combination of vapor pressure and liquid compromise the tank before this point? Or am I missing something altogether? Does expanding liquid propane have the ability to exceed 1000 psi once it fills its container?

Thanks.

The tank is rated at 250 psi with a 4:1 safety factor. The pressure relief valve is assumed stuck shut. From what I've found on the web, the thermal expansion of liquid propane is 0.003 per degree K. Thus, if I understand correctly, 30 degrees should result in a 9% increase. If the tank was initially filled to 92%, then the liquid should expand to fill the tank, and, presumably, the expanding liquid will subsequently exceed the 1000 psi mark and burst the tank. Or, will the combination of vapor pressure and liquid compromise the tank before this point? Or am I missing something altogether? Does expanding liquid propane have the ability to exceed 1000 psi once it fills its container?

Thanks.