On Wed, 26 Nov 2003 08:53:21 -0600, Serial # 19781010
wrote:

Snip

I closed the valves, and used a propane torch to heat the bung until
it was too hot to touch.

Snip

Now, before I get flamed for applying heat to the tanks, let me
explain some logic here.

First, although the tanks were full of LP vapor, there was no liquid,
and there was no pressure in the tanks.

Second, the valves were closed, so no gas was escaping and available
to ignite.

Third, the inside of the tank contained 100% LP vapor. This is not
explosive. The explosive limits for LP gas is between 1% and 10% in
air. Had a fracture occurred, the flame would not have burned into
the tank. The flame would have only occurred where the escaping gas
was mixing with air.

I got advice from people saying to pressurize the tank with air, and
bleed it off a couple of times. This could have easily left me with
an explosive mixture inside the tank. Leaving it full of 100% LP
vapor was MUCH safer.

Fourth, this was a 100 pound LP tank. Heating the bung is not going
to heat the gas inside to any significant amount, and certainly not
enough to risk a pressure explosion. In fact, when the valve was
removed, there was barely any hiss of gas escaping.

Dave

When I worked for the gas company, we had a foreman who would fix gas
leaks in the pipeline by arc-welding them while the gas was escaping.

I don't know if OSHA would allow such a thing, any more.

Orrin