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Safety Question re Oxy-Propane Little Torch Set-up/Hose Dry Rot?
lssphx -
Monday, October 26, 2009 - 10:58pm
Jewelry safety Recently had very bad experience utilizing above set-up in that after firing up equipment after long hiatus to solder a silver bezel... Got it going the usual way, running through all usual steps... flame was running smoothly for about two minutes, just starting to heat up bezel in order to flow solder when the torch/hose erupted into a long 2 foot bushy flame at the hose connection to the torch itself as near as I could determine in my panic at the moment, and dropped it to the floor where it continued to flame. Luckily I had the time and presence of mind to quickly shut off the tank valves, after which the flame went out. I did receive a large 1st degree burn over my forearm, side of wrist and outer portion of thumb, with small blisters forming after two days, but very grateful as it could have been much, much worse! After looking at the torch afterward, it appears that the hose burned through close to where the torch ends connect to the hose. We eventually thought that it might have been caused by dry rot to the hose as the torch has been in an outside workshop with no air conditioning/cooling system and here in the Arizona desert, it probably reaches 120+ degrees in the summer time in that shop. My questions are, has anyone ever run into that with this type of hose? Is there anyway to check for dry rot safely? The hoses themselves were still very flexible in mobility, but are woven-fabric covered so that the inner hose cannot be visually inspected. Any thoughts to other possible causes? Looking for answers before I lose my nerve to ever use a torch again...  Thanks for your reply
lssphx -
Wednesday, October 28, 2009 - 4:15pm
Thanks for your reply Rich... I'll follow these suggestions, as well as storing the new hose inside if I'm not going to be doing any soldering for awhile, like every summer in Arizona. » reply  This surprises me, I didn't
Dick C -
Tuesday, October 27, 2009 - 10:59am
This surprises me, I didn't think the material would break down like that. I do know of someone who had a failed hose that ignited, but I believe that hose was cut or somehow physically damaged. I have seen Little Torch hoses without the outer sheath. The clear tubing had a green or red tint to it. This was quite a while ago though. I've bought hose since then that was the standard fabric sheathed variety. » reply Yikes !
visitor -
Monday, November 2, 2009 - 2:12pm
Very uncommon for that to occur with such a small diameter hose that really doesn't use any 'real pressure' ! I would think that you merely had a 'BAD' Hose and you were 'unlucky'. Also, I notice you didn't mention anything regarding 'Back Flash Arrestors'. If you don't use em' GET THEM'.... They would have saved any degree of 'burn-off' and you likely wouldn't have been burnt as the flame leapt through the hose. The arrestor would have sealed shut as soon as there was any degree of 'burn-back'. I think you'll be plenty safe, once that is taken care of.... Cheers, /Jman... » reply |
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ArtMetal
I would think you're correct
I would think you're correct in your assessment of the dry rot issue. Take the assembly to your local welding supply and have it all checked out to make sure the torch seals were not damaged by the flame and get a new hose assembly. Once the welding shop approves it, you should be good to go.
As far as checking for dry rot in the inner liner of the hose, about the only way is to give it a pressure test periodically using compressed air at about double the pressure you normally run the hose at. That way, if there's a weak area it will give way with a non-flammable gas (air) and no burns. The real test is a "leak-down" test, performed by pressurizing the hose with a gauge in the line and plugging it off. The pressure is checked after 24 hours to determine if any minute leakage occurs. That's probably not necessary 0 the hose is cheap enough to replace every year just to be on the safe side.
Rich