On 2009-11-23, Roger Shoaf wrote:

"Ignoramus25468" wrote in message
...
I would like to convert a 5 gallon steel jerry can into a fuel tank to
hold diesel fuel. To that end, I will need to add three fittings to it
(fuel intake with tube almost to the bottom, fuel return, and breather
fitting).

Presently this jerry can contains diesel fuel.

The way I want it done is to drill holes in the top of the can for the
three aforementioned fittings, and TIG weld them on.

To avoid explosion, my plan is to drain all diesel fuel from the jerry
can, and fill it with water almost to the top, so that ony very little
space is left between water and where I will drill and weld.

Would that be a basically safe thing to do. thanks


i

I think I would avoid finding out. Three things come to mind.

First, you could weld the fittings to the cap. (Run the pick up line
diagonally)

Next, you could use gasketed fittings rather than welding them.

Or, buy a new can for the project.

To answer your question I do not think a water purge is a good idea. I
think the way to weld a fuel tank is to purge with an inert gas, and keep
the tank under a positive pressure with the purge gas while welding. Chunks
of dry ice might be viable.

As a matter of first impression, a new can would be cheap enough not to risk
a failure of the purge and the resultant explosion.


It is not a purge, the jerry can will have water filling it almost to
the level of where I will do welding.

i