On Sun, 30 Mar 2008 12:09:59 -0400, WaIIy wrote:

On Sun, 30 Mar 2008 17:07:28 +0700, Bruce in Bangkok
wrote:

On Sat, 29 Mar 2008 21:59:03 -0700 (PDT), RichH
wrote:

Bruce is somewhat correct ... the tank has to be padded with an inert
gas such as Nitrogen, etc. Welders on transmission lines 'hot-tap'
repairs all the time ... just need someone who KNOWS how to weld
such.


The point about making a hot tap is that you are welding on a closed
pipe that is filled completely with oil - no air. some what different
then an empty tank.

I have no idea why the A.F. procedure was to steam the tank. Certainly
we had all kinds of inert gas available but that was the procedure.
Maybe because it worked?

In high school shop class, I had a lawnmower gas tank I wanted to
solder.

I washed the tank with host soapy water and let water run through it for
about ten minutes. I then waited for it to dry.

As soon as I hit it with the torch, kaboom and there went part of my
left eyebrow.

Lets not get to telling "welding and it blew up" stories. I've got a
couple that will make you cringe.

Bruce-in-Bangkok
(correct email address for reply)