Gas cylinder welding fire - GIF

[Frank S]

The son of the Blacksmith at the shop where I worked as a kid got called to hot tap a high pressure nat gas line while under pressure. He and I went out I ground the pipe clean then he welded the nipple in place then the gas company screwed the ball valve on then they screwed in a piercing tool into the valve. I much larger version of the freon puncture device you would use to add freon to your car's AC they screwed it in then backed it out closed the valve and removed the tool not a bit of Nat gas was lost from the 3000 PSI line.
I've repaired a lot of cracks in fuel tanks on equipment. Not the easiest thing to do diesel is oily and makes it hard tro weld but if you burn hot enough and keep the fuel level above the weld it works OK but not for the faint at heart or inexperienced you can get yourself and others killed.
When it comes to cutting open a used propane tank filling with water is not good enough as the propane permeates into the metal. Even if the valve has been removed and the tank has been open to air for a number of years filling it with water then cutting into it with a torch it will still huff always cut from bottom up and keep water filling it until you have it nearly cut all the way open and even then it could explode. I've seen guys steam clean the 250 and 500 gallon propane tanks for several hours getting the tank hot to the touch then filling them with a solution of baking soda and water and letting them set for a few days before cutting them open while forcing CO2 in them. Personally I stay away from cutting them with a torch or grinder all together. I have filled them with water then drilled a hole nad used a saber saw by cutting from the top. Not TOO much danger in that since there is little to now air space
As far as Making BBQ grills out of things like this especially Propane tanks a huge hot fire needs to be built in them many times and kept hot for hours and hours to ever get the smell out.
I made a BBQ grill for an oilfield company a long time ago out of a 1000 gallon pressurized fuel tank. the steel was about half an inch thick We must have burned a cord of wood in it with forced air to get it hot enough to burn the fuel out of the steel. It was fine after that
But in capping by far the best way to make BBQ grils out of drums is like previously posted use a new of whats is known as a virgin drum

[JoeVanGeaux]

Not sure what we have here. I wonder if this is a fuel theft gone wrong.

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To clarify (and someone please correct me if I've got this wrong) - to cut open a vessel that may have once held fuel, you first fill it with water. Then you can grind or saw away as much as you want, correct?

That depends on whether you are trying to remove a section of your barrel or a section of your legs.

[toma]

The knowledge is limited, but stupidity is endless..

[greenie]

An Aussie perfected cutting the top out of used 44 gal petrol drums with a gas axe way back in the late 1940's.
All you have to do is change the air fuel mixture, you do this by inserting a compressed air hose into one of the open holes at the top of the drum, turn on the air pressure and all the harmfull exploding vapours are blown out of the other open hole.

Into it with a gas axe/angle grinder/whatever and do what you want to the drum now.

Don't believe me, then you better do a google for a fella by the name of Kurt Johansson from Alice Springs.
After the 2nd WW the yanks left hundreds of thousands of old petrol drums behind just laying around the countryside, so Kurt went out and retrieved them, did what he had to do and on-sold them making a lot of money out of it.
He even invented the self tracking trailer, so a Road Train virtually follows in the path of the first trailer.