Thanks all for the info regarding acetylene and the 15 psi "danger zone"! I never know this, and I guess have just been fortunate to never have set the pressure above a few pounds. I never have had any training using the torch, just watched a guy use one for a few minutes, made some mental notes, and bought my own. The H.A.M.B. never ceases to impress me with the breadth and depth of info that is posted here!
5lbs acetylene 35lbs oxygen is best combination I've found. If your are cutting less than 1/2" use a 00 tip. The tip is not seated or the mixing barrel may not be tight or flame not adjusted right causing the backfire. Adjust the acetylene to where the flame just starts to jump off the tip. Add oxygen till the flame cones come together sharp. When you hit the air trigger and it sounds like paper tearing about a foot from the tip it's ready. Acetylene becomes unstable above 15lbs., it may spontaneous combust. The acetylene bottle has acetone in it to stabilize it. Never use an acetylene bottle on it's side, it will lose the acetone. Only open acetylene tank valve 1/8 turn. Open oxygen tank valve all the way. Oxygen tank valve has a seat in the fully open position to keep the packing from leaking. Be safe, Harley
I guess this is a good thread to ask this question. I've been told the flame arrestors are only good for one backfire. They are made of a material that fuses together and won't function after that. Is this true?
Maybe just maybe they should put a big red danger symbol on the regulators so folks know not to go over 15 lbs. And a reminder for those that may have forgot. Seems they already have thought of that ...... http://www.atlweldingsupply.com/***ets/images/acetylene regulator.jpg To the op, Your pressure is too high for the small tip or your the mating surface of the tip to torch head is messedup.
If you have a backfire thru the torch body that is hot enough and big enough to melt those you'll be needing a new torch body, and You will probably be headed to the ER too. Not likely to happen under normal cir***stances following long established safety procedures and properly functioning equipment. A fire inside the torch creates a high pitched whistle with a flame out at the tip. Those stop the fire from traveling up the hose back to the bottle. Under all but the most freakish of cir***stances you'll have plenty of time to shut it down before the fire reaches them.
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