Acetylene Blowout

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I had bought a new Acetylene cutting outfit since I left mine in Fl.  I was using it today, and I thought that it had a blowout resister built in.  Obviously not.  My Acetylene tank wound up blowing out of the side, what I think was kinda like a blowout valve.  Where it blew, its a small threaded hole around the base of the main valve.  It is actually in the cylinder.  Once that happend, my tank started spitting fire.. blah blah blah.. sucked.  I grabbed my fire extinguisher that was 2 feet away, and put it out.  Thank God, without any major incidents.  My question is, was that a blowout valve?  If so, any ideas where I can get a replacement?  Thanks!Kevin
Reply:What you describe sounds like what is typically called a "pop-off" valve, but good gawd man there shouldn't be any fire there unless you waved the torch to it while it's venting!!!!!!!! Could be you've got serious problems here, and could be talking big bucks.Without going into a two day rant here's the basics with tanks and devices:1) all pressure vessels have a pressure relief valve (pop-off). In the event the internal pressures rise to a point beyond the rated capacity or to a highly dangerous condition that valve pops, or releases some of the pressure till it reaches a safe point. Remember, releasing volitile gas is not desirable so this valve condition is a "last line of defense" mechanism.2) For cutting outfits there are also devices called "flash suppressors", or anti-burn back devices. These keep flame from running back up the hoses and into the low side of the regulators. They fit near the torch body. Get some. They are spendy.3) There are also check valves. These help prevent swapping gases in the regulators do to the differences in pressures between one hose and the other. They fit near the regulators. Get some. Pop off valves do and can fail but in the world of acetylene it is very rare. Could be there was an errant overfill, but again extremely rare. Could be you had a fire run back up the acetylene hose. Rare but not unheard of. That's what the adjunct devises are for. In this event there is generally serious damage to the regs, o-rings and other components. In any event get the torch head, hoses and regs into a shop for a complete checkout. Take the tank to the local gas distributor and have it checked.Good luck.Last edited by Sandy; 10-23-2005 at 01:52 PM.
Reply:i will definitely get some flash suppressors.  From what i saw, the flame did run up the line.  I was not anywhere around the tanks when it happened.  I saw a flare up by where the hose connects to the tank, than when the blowout happened, it lit where the pop-off came out.  The pressure in the tanks looked ok, and I was not doing any Intensive welding or cutting.  i actually had the flow from the tanks down low.  Thanks for the input!