General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
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Bmuxxx
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Hey guys, I have to weld a gas tank that has previously had gas in it. Just wondering how I should prep it so I can safely weld it. I remember from school I could clean it out and then Purge it with dry ice or argon. Just wondering if there's an easier or cheaper way? Thanks
cj737
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Detergent and water depending upon type of gas.
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This topic just beat to death in other posts with every voodoo trick and no,no explained.

Some work
Some explode
Safe = New Tank
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Poland308
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I purge propane and natural gas lines with nitrogen.
I have more questions than answers

Josh
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Pour a cup of vinegar & half a box of baking soda in the tank, in a minute it'll be full of co2, put cap on loosely & rotate tank so liquid is not where you wanna weld. Rinse out the tank when you're done, , , ,
 
 
 
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tweake
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cornmuse wrote:Pour a cup of vinegar & half a box of baking soda in the tank, in a minute it'll be full of co2, put cap on loosely & rotate tank so liquid is not where you wanna weld. Rinse out the tank when you're done, , , ,
i thought rick was kidding when he said "voodoo trick", apparently not !
its things like this that tend to cause problems. fine in theory but if there is fuel still in there and not enough co2, its boom time.
afaik the pro's fill the tanks with water. fuel is easy enough to wash out. filling it with water as much as possible will reduce air space and most important leave the cap off !
the pro's do this all the time so there must be a procedure around for it.
tweak it until it breaks
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Bets? I'll bet this goes to 3 pages!
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Turbo
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Bmuxxx wrote:I have to weld a gas tank that has previously had gas in it.
Umm... No you don't!

When all you have is a hammer everything looks like a nail right. You didn't say what kind of tank it is, so I'll assume It's a very rusty automotive tank.

Is J-B Weld resistant to water and/or gasoline?
When fully cured, J-B Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical. For wet-surface or submerged water or gasoline repairs, try our SteelStik or WaterWeld.
https://www.jbweld.com/pages/faqs
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tweake
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tungstendipper wrote:Bets? I'll bet this goes to 3 pages!
o yeah.
this is a reason why
http://www.nzherald.co.nz/nz/news/artic ... d=11938652
http://www.employmenow.co.nz/2017/11/27 ... od-enough/
tweak it until it breaks
sedanman
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A few users ago I modified a motorcycle fuel tank. I drained the tank and removed the fuel pump. I let it air dry then took my hand-held leaf blower and set the tank on my lawn with the output of the blower running through the tank. I burned a whole tank of fuel on the blower. When I was done there was not a trace of fuel odor in the tank. It worked. Your mileage may vary.
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