Welding On 100 lb Propane Tank Questions

[KennethBrown]

Ahh, pull the bung, fill it with water and build a fire under it. When the water boils drain the sucker and start work!

Now thats a response that makes sense!

 

[gordon21]

Your solution is so simple you don't even see it. Your buddy has plenty of empty tanks. Take him a couple cases of beer and ask when your tank will be ready. Let HIM do it.

 

[Tim Stuart]

Why not get a cardboard Sona tube from the big box store and put a PVC piece of pipe through the center of it and fill it full of concrete. That way you live to use it.

 

[excelagator]

I do appreciate the replies and the kind words of caution. Believe me I like my body parts here and not a little there and a little over there. I have seen the 500 gallon roller from Freaky acres. I have seen people cut up 500 gallon tanks into fire rings for good $$$. The best is a artist with a plasma making fire "dishes" out of them for $500.

I am not sold it is truly that dangerous or all that safe! Just somewhere there is a safe way to do it.

I would build it from concrete, but I do want to weld 1/8" fins on it for aerating at the same time I roll it. Plus a hot water tank is not going to last long with my hidden boulders.

Dan

 

[Rara Avis]

I do appreciate the replies and the kind words of caution. Believe me I like my body parts here and not a little there and a little over there. I have seen the 500 gallon roller from Freaky acres. I have seen people cut up 500 gallon tanks into fire rings for good $$$. The best is a artist with a plasma making fire "dishes" out of them for $500.

I am not sold it is truly that dangerous or all that safe! Just somewhere there is a safe way to do it.

I would build it from concrete, but I do want to weld 1/8" fins on it for aerating at the same time I roll it. Plus a hot water tank is not going to last long with my hidden boulders.

Dan

You could jamb your aerating fins or plugs into the concrete as it is setting up...Just remember it takes 28 days for it to be fully cured...

 

[AlanB]

I am not sold it is truly that dangerous or all that safe! Just somewhere there is a safe way to do it.

Plus a hot water tank is not going to last long with my hidden boulders.

Dan

It is truly dangerous if not done correctly. Do you have the equipment to monitor the gas levels in the tanks while you are cutting?

A hot water tank is normally a heavier gauge tank, not to mention usually glass lined, then a propane tank, so, I guess I do not follow your last comment. The only thing that comes to mind is that you are thinking of what you see when looking at the outside of a tank, not the actual tank itself.

I made several with old water tanks ($5 each from the local scrap guy) and they worked well.

I used masonary cut nails as my spikes, made a quick, durable easy spike at a good price.

Made flip over frames with wheels sticking up on one side as the tow points.

Hope it works for you.

 

[SPYDERLK]

I do appreciate the replies and the kind words of caution. Believe me I like my body parts here and not a little there and a little over there.

I am not sold it is truly that dangerous or all that safe! Just somewhere there is a safe way to do it.
Dan

The key is that you must continually flush the tank to prevent inflammable vapor buildup while welding. This will prevent at least a vast proportion of the volume from getting to an ignitable concentration. That way, even if it ignites in a stagnant region that might, via Murphy, be proximal to the weld, you just get a puff rather an explosion. The absolute best thing of course would be to use a gas that does not support combustion, but even so, plain air is an effective flush. Just be prudent and dont stand in front of the hole.
larry

 

[bx24]

Ironically, I think the tank is probably safer to weld / cut if the inside is still pure propane. I would not have said this a couple of years ago, until I talked to a guy who was welding on a natural gas pipeline. I asked him how the purged all of the gas when they cut in a new "T" and he said they didn't. They simply lowered the pressure but that the gas was blowing out while they were welding! He said because there was no oxygen in the pipe, the gas would not ignite ... basically it was running too rich. He also said we would be safer (I work for a telephone utility) to hit a high pressure main for this reason than a low pressure pipe (at least from a fire perspective).

If you still want to do it, pressurize the cylinder with your compressor and crack the valve and try to light the escaping gas. If that won't light, neither with the heat / flame from the welder.

 

[SPYDERLK]

Ironically, I think the tank is probably safer to weld / cut if the inside is still pure propane. I would not have said this a couple of years ago, until I talked to a guy who was welding on a natural gas pipeline. I asked him how the purged all of the gas when they cut in a new "T" and he said they didn't. They simply lowered the pressure but that the gas was blowing out while they were welding! He said because there was no oxygen in the pipe, the gas would not ignite ... basically it was running too rich. He also said we would be safer (I work for a telephone utility) to hit a high pressure main for this reason than a low pressure pipe (at least from a fire perspective).

If you still want to do it, pressurize the cylinder with your compressor and crack the valve and try to light the escaping gas. If that won't light, neither with the heat / flame from the welder.

The 1st part is good. The 2nd is a possible gotcha in 2 ways; 1) if it does light it can follow the inflammable mixture back into the tank, further pressurize and explode, or 2) welding heat can free otherwise trapped combustible gas pockets stored in the metal in a liquid or a molecularly combined form, thereby enriching the too lean unheated unpressurized, but homogeneous, tank mixture to a level that would ignite pressurize and turn into a missile or explode. A continuous flush gets around these with a high margin of safety.
larry

 

[Egon]

[COLOR=red]Ironically, I think the tank is probably safer to weld / cut if the inside is still pure propane.

[/COLOR]

Let me know when this fellow is working near me cause I would surely like to leave.

Seems he hasn't heard of vapour clouds or such finding combustible conditions away from the immediate work site.

If you wish to use an old propane tank pull the bung [bungs] fill it with water and build a fire under it and steam it out. Easier if you have steam available and just put a steam hose into the tank and position the tank so it can constantly drain out.