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Oxy/Acet torch Pop

ColMckee

Aluminum
Joined
Apr 8, 2006
Location
Mo
Why does my torch POP and sometimes extinguish itself when I'm using it? Usually this happens when I get the tip too close to what I'm heating, but not always. Wrong pressure, maybe? Been doing this for 30 some years and never bothered to ask because the job always got done and then I'd forget until next time. Thanks...
 
yup, usually its the pressure not set right, your LWS should have a cards that have the different pressures for different size tips, usually these sell for as much as zero dollars and you could probably find them listed on the web.
 
Used to work with a guy who was an engineer with Linde/Union Carbide. He finally explained OA welding in a way I could understand. If your torch is popping and going out, you need to go down one tip size.

Popping is generally caused by trying to weld thinner material with a large tip. This means you have the flows cut way back to keep the heat down. The flow of gasses out of the tip keeps the flame pushed out of the mixing chamber. If the flow through the tip is too slow, the flame backs up into the mixing chamber and you get the pop. Going down a tip size means the flow has to be cranked up to get the same amount of heat, thus the speed through the tip is increased and the torch does not pop.
 
If it happens when cutting, some people will blame the torch itself, too. I had a Craftsman deluxe 2-stage outfit from back when they still sold good stuff, which behaved very well. I can't remember who made it, but I loved that torch. It was stolen, and I replaced it with a Smith's set, and the cutting torch has always popped and blown out. I was helping someone cut up a piece of old equipment, popping and cussing and relighting, and he didn't even have to look at the rig to tell me I must be using a Smith's torch. For cutting torches it's really important to have the tip seals seated properly, and for Smith's torches, which have a graphite gasket, that seems to mean a new tip more often than you think you need it.:mad:
 
I have been in the welding and torch welding and "cutting" business since the late '50's. Over the years I have had several different cutting torches. Currently I have a medium duty "torch" that I bought from Northern tools. I have been using it for almost a year with some serious cutting time, with no problems. All of a sudden I'm having a serious popping and flame out, first with a number 1 tip, and now with a number 2 tip. NEVER before have I had this problem with this severity. I've adjusted oxy and acet up and down. Acet pressure never over 9 lbs. and oxy from 40 lbs to 50 lbs. and lastly down to 30 lbs. I have cleaned, not lapped the the tip connection. I noticed that where the torch body screws onto the base that the area of the connection is wet. I have never seen that before. I am past frustration .... any ideas?
 
Used to work with a guy who was an engineer with Linde/Union Carbide. He finally explained OA welding in a way I could understand. If your torch is popping and going out, you need to go down one tip size.

Popping is generally caused by trying to weld thinner material with a large tip. This means you have the flows cut way back to keep the heat down. The flow of gasses out of the tip keeps the flame pushed out of the mixing chamber. If the flow through the tip is too slow, the flame backs up into the mixing chamber and you get the pop. Going down a tip size means the flow has to be cranked up to get the same amount of heat, thus the speed through the tip is increased and the torch does not pop.

Kind of like college students lighting farts. If the gas velocity is less than the flame propagation velocity somebody gets burned.
 
It doesn't sound like this is your problem, but another cause of a "rhythmic" popping, meaning continuous, occasional popping like every second or two, can be caused by a leak somewhere. Either in the torch itself (tip not seating tight, valve loose, etc.) hose connection or tank connection, etc.. Atmospheric air getting into the system can cause continuous popping. I was told this by the guy who used to fix all the torches at a place I worked. You would think that the gas and oxygen pressure would just blow out and not let air in, but sure enough, after tightening things up the popping always went away. Go figure...

Ted
 
It doesn't sound like this is your problem, but another cause of a "rhythmic" popping, meaning continuous, occasional popping like every second or two, can be caused by a leak somewhere. Either in the torch itself (tip not seating tight, valve loose, etc.) hose connection or tank connection, etc.. Atmospheric air getting into the system can cause continuous popping. I was told this by the guy who used to fix all the torches at a place I worked. You would think that the gas and oxygen pressure would just blow out and not let air in, but sure enough, after tightening things up the popping always went away. Go figure...

Ted

Eons ago I used a Craftsman combination torch that always went pop pop pop. There was a small leak either between the tip and the head of the torch or between the handle and the cutting attachment. An old Prestolite torch did the same thing when the cutting tip did not seat properly. A Marquette combination torch also did that when the o-rings between the handle and the cutting attachment needed replacement.
 
Eons ago I used a Craftsman combination torch that always went pop pop pop. There was a small leak either between the tip and the head of the torch or between the handle and the cutting attachment. An old Prestolite torch did the same thing when the cutting tip did not seat properly. A Marquette combination torch also did that when the o-rings between the handle and the cutting attachment needed replacement.

Interesting....My Airco cutting torches (with the morse taper looking tip seat)
They just have a little pilot light next to the tip nut when the seat is bad.
 








 
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