Drilling and brazing a fuel tank

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Yes, they were all about tanks full of gasoline when they exploded.
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No, but like I said, they probably did not observe the precautions.
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I will do just that and will video tape it too
i

wrote:
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If he's pointed the right direction you might not even need to have it delivered!!!
Anyone who cuts or welds on a container that has EVER contained gosoline or other flamables without taking adequate precautions is a fool and an idiot. And "adequate" does not mean "barely adequate", or "should be good enough".

Ignoramus15459 wrote:
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Like I said, blow yourself up. I had a 30 gallon tank from a '73 Chevy Step Van blow up on me. It had been empty for over two years. It was full of water, but it jumped five feet in the air and sprayed hot water all over me and a neighbor. It peeled most of the crimped seam apart, and destroyed the tank

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Then, Michael, it wasn't gasoline fumes, it was welding gasses -- or....
if it was "full of water", how, exactly, did you get a volume of gas in there to explode? Could it have been steam pressure, which you inadvertently caused by trying to cut or weld on a part immersed in water?
LLoyd

"Lloyd E. Sponenburgh" wrote:
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It was on the neck. Just a few inches of metal that wasn't under water. It turned out the inside of the tank was quite rusty, which wasn't visible before it blew. I talked to a couple people who repaired tanks before I tried to repair it, and was assured that nothing could go wrong. They just stood there and scratched their heads after they saw the results. This was in a steel town, where professional welders and machine shops were thick as thieves.

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Well... "sitting on empty" and "empty, and open to the air" for two years are two different things.
I assume (unless welding gasses were the culprit) that there had not been adequate ventilation of the tank.
I've modified numerous "pulled from service" gasoline and propane tanks (of course, emptied, dried, purged, and filled with inert stuff before work), and not had any even _minor_ malfunctions. And usually, all that folderol takes longer than the modifications do.
I deal with a surprisingly high-tech welding/cutting shop in our little town of 2000 that welds repairs on RV gas tanks as a regular part of their business, and they don't have those problems, either.
If it's gasses that are your problem, a _slightly_ oxidizing flame is your friend -- no free fuel, either in the form of gas or air-suspended particulate carbon, gets into the tank by accident.
As part of my practice on propane tanks, I also wash out the mercaptan, which _can_ form an explosive mixture. (household lye converts it to other stuff which can be washed out with water)
LLoyd

"Lloyd E. Sponenburgh" wrote:
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Empty, with no gas cap for over two years. also, there was a seven inch long stress crack in the bottom that would leak, until there was less than a gallon in the tank over a weekend. That was why the truck sat unused for over four years, and a little over two with no gas cap. I took the locking cap for another truck I owned.
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The only thing available to work with was a cheap SolidOx torch, with a small bottle of propane.
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On 2011-07-12, Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:
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Exactly.
The tank may have had little usable fuel, but was closed and trapped the remainder and the fumes.
In my case, the tank is dry, the inlet is open, and I turned the tank over so that it sits outside, under the sun, with the open inlet pointing down.
i

On Tue, 12 Jul 2011 21:37:57 -0500, Ignoramus15459
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Trust me Iggy - it is STILL a potential bomb. What does a CO2 fire extinguisher refil cost????? Fill the tank with a shot of CO2 untill you see it flowing out the top (as a fog). Let it sit, filler up, for a moment, then add a bit more. Weld with filler up, and new fitting snugly in the hole, and plugged so the CO2 does not all flow out through the fitting as you weld/braze/solder.. If the job takes very long - give it another shot part way through - and you can GUARANTEE you will be here, and in one piece, the next day.. REmember, CO2 is almost twice as dense as air - but not NEARLY as dense as you if you weld that tank without taking "proper" precautions.

snipped-for-privacy@snyder.on.ca fired this volley in
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Ibid, my last.
LLoyd

On Jul 15, 11:04 pm, snipped-for-privacy@snyder.on.ca wrote:
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A lot more than some dry ice that someone mentioned.
Dan

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And a lot more than filing the tank with water from a garden hose.
i

On Sun, 17 Jul 2011 07:33:21 -0500, Ignoramus26063
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Whicm may, or may not, be as safe.

On Sun, 17 Jul 2011 05:04:48 -0700 (PDT), " snipped-for-privacy@krl.org"
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Depends where you are. Getting dry ice in some areas is not nearly as SIMPLE... But yes, if available it will definitely work - and well.

On Tue, 12 Jul 2011 16:22:09 -0500, "Lloyd E. Sponenburgh"
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Nope - it was gasoline vapour. Had it happen to a friend on his 50's ford tank. He'd flushed it with water, let it sit in the sun, and filled it with water again - stood it against the shop wall and started to braze it. It heaved and buckled and knocked him on his ass on the other side of the driveway. They figured out there was gasoline "locked in" to the rust where he was doing the repair - perhaps 1/10 of a teaspoonfull at the very most - and when he heated it, the rust was reduced to iron and oxygen - which mixed with the gasoline with extremely un-expected and violent results.
DON'T DO IT.
If the tank had been full of CO2, Nitrogen, or Argon (I prefer CO2), the oxygen and gasoline vapours would have dissipated into the CO2, instead of being trapped and concentrated - and combustion would have been IMPOSSIBLE.

snipped-for-privacy@snyder.on.ca fired this volley in
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I believe that is pure BS. Sorry... I'm not impuning YOU, but the "solution" you describe was obviously mis-stated to you. It's garbage. If you cannot _smell_ gasoline fumes, they cannot form an explosive mixture.
I'm pretty clear on that matter, being involved in the "flammable chemicals" industry.
LLoyd

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We covered such in firefighting class when I worked on a pipeline. You use a different tactic on BLEVE's:
a) Recognize BLEVE b) $^%&%$& RUN ....
We welded tanks/pipelines all the time.
1) Jethero shoots a hole in same.
2) Pound in rubber plug.
3) Let dry
4) Ensure either good line rate, or sufficent tank fill above weld. [~2 ft comes to mind; less if Diesel than gas.]
5) Lay patch atop plug {can't recall size but say 8" dia.]
6) Weld in place.
Of course, these were slightly larger than the average car's tank; say 60' diameter and 40' tall. And there was NO problem welding to a wall of say 0.375" thick.

On Mon, 11 Jul 2011 21:43:27 -0500, Ignoramus24437
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You're probably right. But, I'd use the suspenders and belt approach. No fuel plus no O2 = double safe.
A garden hose from your car exhaust to the tank only take a couple minutes.
Karl
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On Tue, 12 Jul 2011 06:05:48 -0500, Karl Townsend
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A garden hose from the exhaust is NOT going to do the job.
For cripes sake - BORROW a CO2 extinguisher if you are too cheap to buy one, and get it refilled when you are finished. Your ass is worth more than 10 bucks!!!!
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Maybe more mis-information than BS.
Gasoline tanks are repaired or modified commercially every day, with complete safety.
Empty, wash, dry, bake out, and purge with an inert substance.
If you can't smell the gasoline, there's not enough present to form an explosive mixture.
LLoyd