100lb propane to air?

[Craig Clayton]

I did another quick goggle, the following is a copy and paste.
Propane tanks are equipped with pressure relief valves that vent excess pressure. If the tank gets too hot, the tank will fart instead of explode.

Normal propane cylinders, such as those used with portable grills have pressure relief valves set to 375 PSI. PRV settings for ASME (American Society of Mechanical Engineers) tanks are 250 PSI. DOT engine fuel cylinders use PRV settings of 312.5 PSI.

During manufacture of propane cylinders for engine fuel storage, each propane cylinder must be exposed to two times its service pressure, and one out of every 500 cylinders is exposed to four times its pressure, or about 960 PSI.

It would seem that propane tanks are built to withstand at least 250 PSI. I think it logical to assume that any propane cylinder you are likely to encounter can withstand at least 200 PSI virtually indefinitely.

So, what kind of load will we be putting on them? Regulations for home and shop air compressors limit them to 125 PSI.

I think propane tanks can safely handle the pressure that a home compressor can dish out.

Converting A Propane Tank For Compressed Air
I would like say in closing let your conscience be your guide.
I did not mean that I Put 250 PSIG in a forklift tank.
Craig Clayton

 

[George2615]

I think you could make an air tank out of this. You will probably need to mount it on a cart to roll it around. Probably too heavy to lift.
I made a portable air tank from 2 used 30 lb. R-22 tanks connected together. It has worked well for over 15 years with no leaks.

 

[SandburRanch]

And then for the simple solution one could always fill the tank, leave it by the trailer and gas the tires up. Real common on the farm in the 1950s and 60s.

 

[cotter]

The 100# cylinder will work just fine, I have used one for a while now. As stated the propane tanks are designed for over 300 psi so our ~125psi for air is no problem. ~24 gallons to the 100# cylinder. The tare weight will be stamped on the ring around the valve, ~65# empty weight. Most of these can be had out of hydrostat test date free, rental yards find it cheaper to buy new tanks instead of testing their old ones and the fact that it is a pressure vessels makes it hard to dispose of (scrap yards won't take them). You will get the mercaptain smell out of it for a LONG time, but the tires don't seem to care.

Supplies needed:
POL to 1/4" NPT adapter, can be had at TSC etc.
1/4" Female QC
I use a double male fitting to full the tank. Close the valve and connect double male to the tank. Connect your source air and open the valve to fill the tank. Shut valve and disconnect air source, then double male from the tank.

I suppose I should paint on the outside of the tank that it is air, not propane but nobody but me uses it. These tanks are very tough, I have plenty of them and make a regular habit out of putting holes in them with high speed lead. Most pistol bullets will bounce off of them and many rilfe bullets will not go thru both sides (then the scrap yard will take them :thumbsup: ). I would have no issues with putting 250psi worth of air in one of these tanks in good condition, though I would want a regulator on the output side. One of these days I am going to get smart and use the 30# aluminum tank that I have for my air tank.

Chad

PS long time lurker, first time poster. Hi guys.

 

[David Devuono]

The 100# cylinder will work just fine, I have used one for a while now.

Chad


Chad like you, I believe it would make a great air tank. Just don't think spending 117$ will get you a great portable air tank. For stationary use, it would be more then up to the job. For my 117$ I would buy a good 12V air compressor or longer hoses.

 

[handirifle]

Or you could do what I did a long time ago. http://handirifle.com/articles/Onboardair/onboardair.htm No need to keep worrying about hauling a tank around, or not having it when you need it. I kept (no longer own the Jeep, but will put one on my truck soon) a 20' coil of air hose and fittings in a small bag. Worked like a charm.

 

[Ductape]

I've also got an older (no valve guard) 100 pounder you can have if you want it.

 

[chad22]

I've used a small propane tank before as an air tank.

Chad

PS long time lurker, first time poster. Hi guys.

By the way. Hi Chad. From another Chad welcome to the TBN Forums.

Chad. lol

Great to have another Chad on the forums. :laughing:

 

[cotter]

David Yes sir, a bit expensive to go buy. I picked mine up from a rental yard for free. It is out of hydrostat date but only putting 125 psi in it I am not concearned in the least. I have all of $0 in mine, the POL adapter was on one of the tanks I picked up and I had the female QC in the tool box. I have considered putting one next to my compressor to increase the tank size so the compressor would run less often.

I have thought about the truck mount compressor but I can not always get a truck where I need air. The 100# cylinder fits right nice in the loader bucket, easy to throw in the bed of the truck and I suppose you could strap it to a bigger quad or Gator type vehicle.

The ONLY answer, nah but a good cheap (if you can find it right) alternative.

Aren't us Chad's great? Pregnant or hanging?

Chad