Airsoft Canada - View Single Post - Gas Storage Devices? Are they safe? Explode?

MadMax · August 16th, 2006, 12:42

The fill valve on the GBT nade has the same thread as the WA magazine fill valve. You have to be careful though: there are no overflow features in the GBT nade so it's possible to overfill them. You have to leave a gas headspace (min 20% gas).

A container completely filled with liquid propane can be subjected to very high pressure if the temperature rises. If there is no gas headspace, the pressure is determined by the expansion coefficient of the liquid instead of the saturated pressure of propane (no gas-liquid equilibrium).

Not very hard to prevent though. I fill my GBT nade tilted on a 45deg angle so the liquid level rises to the valve before it can completely fill. I considered machining end caps with the necessary overflow features, but decided against it. It wouldn't be cheap for me (low volume) and all VFC has to do is fix their design and my product is obsoleted.

August 16th, 2006, 12:42	#12
MadMax Delierious Designer of Dastardly Detonations Trader rating Join Date: Dec 2001 Location: in the dark recesses of some metal chip filled machine shop	The fill valve on the GBT nade has the same thread as the WA magazine fill valve. You have to be careful though: there are no overflow features in the GBT nade so it's possible to overfill them. You have to leave a gas headspace (min 20% gas). A container completely filled with liquid propane can be subjected to very high pressure if the temperature rises. If there is no gas headspace, the pressure is determined by the expansion coefficient of the liquid instead of the saturated pressure of propane (no gas-liquid equilibrium). Not very hard to prevent though. I fill my GBT nade tilted on a 45deg angle so the liquid level rises to the valve before it can completely fill. I considered machining end caps with the necessary overflow features, but decided against it. It wouldn't be cheap for me (low volume) and all VFC has to do is fix their design and my product is obsoleted. __________________ Want nearly free GBB gas?