SpudFiles

http://www.spudfiles.com/combustion-can ... 25541.html

do you happen to know what pressures does that gas tank hangs on ? i used one of this as an air chamber for an airgun, and i am not so sure it is as good as i was thinking.

I wouldn't generally consider LPG (or similar) tanks particularly great pressure vessels. An LPG tank isn't designed to withstand particularly high pressures, and the disposable ones are supposed to be cheap, not durable.

In light of the link Jack posted regarding the Bernzomatic tanks being prone to fracture at the neck, I'd say there's good reason for being very wary when using the tanks (at least of that design) as pressure vessels.
A deeper reading of that site shows that this is not inherent to every cylinder (only some have the poor weld at the neck) and only affects those containing MAPP (which seems to be more corrosive than Propane). So a lot of cylinders may well be relatively safe.

Still, relatively safe isn't something I'm a big fan of - and even if a failure is likely going to be considerably less hazardous than several hundred grammes of flammable gas being released in the vicinity of an open flame, there's still potential for harm.

My recommendation would be to not use it - but this is not necessarily the same thing as saying it's dangerous.

The typical working pressure is about 8 bar. In the event that the tank gets hot it could reach 20 bar (50*C) so I presume they are rated to 20 bar.

A friend who works with butane aerosol cans says they are rated to 15 bar in the UK so the logic follows.

Biopyro wrote:A friend who works with butane aerosol cans says they are rated to 15 bar in the UK so the logic follows.

Rated to, or is that their fail pressure?

Rated to 15, apparently burst around 18.