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Ian B
07-15-2006, 06:11 AM
I'm switching over to oxy propane (from oxy acetylene). It's common practise with acetylene to install flashback arrestors on the torch end and/or bottle ends of the hose; should I do the same when using propane?

Do acetylene flashback arrestors work equally well with propane, or are special ones made for the purpose?

Thanks,

Ian

torker
07-15-2006, 08:41 AM
Ian, that was an interesting question so I did a Google search. The first hit...
http://ch3ch2ch3.tribe.net/thread/4f019e8a-1222-402d-a834-26c657fc9fc7

Tin Falcon
07-15-2006, 12:10 PM
Ian:
Quote from Victor Thermadine Oyy-Fuel Welding cutting and heating guide. " Flashback arresters can be used with oxy-fuel gas welding,heating,cutting and allied processes."
It is my understanding they work for all fuels but more important for Acetelene because it can be unstable. The above mentioned guide is available free from victor. either as a PDF download or in print form from the local weling supply house.
Web link is http://www.thermadyne.com/victor/literature/pdfs/70_2510.pd
Regards
Tin

BillB
07-17-2006, 01:27 AM
Those arrestors are check valves, so they shouldn't care what you're running through them.

FWIW, you might want to leak-check regularly when using propane. That stuff is heavier than air (unlike the other common fuel gasses) and pools when leaking, instead of immediately dissipating. I've found that small, unsmellable leaks of propane or acet. induce a teeth-gnashing bad mood in me, an effect not mentioned in any of the MSDS's I've read.

BillB

Ian B
07-17-2006, 01:49 AM
Thanks guys, i'll fit them to the torch.

Bill, how do you separate out the effects of breathing propane from all the other things that cause a bad mood in the workshop (taking one cut too many, a workholding setup not being *quite* secure enough, etc etc...)

Ian

Evan
07-17-2006, 01:55 AM
I've found that small, unsmellable leaks of propane or acet. induce a teeth-gnashing bad mood in me, an effect not mentioned in any of the MSDS's I've read.

Acetylene is a mild anesthetic and can make you buzzed if you breath much of it. It can leave you with a serious headache.

BillB
07-17-2006, 03:06 PM
Ian,

That's what I thought at first, but then I had a couple of experiences where I recognized the symptoms and went on a "search-and-destroy" mission, leak-testing every rig in the shop until I found & fixed the leak.

Initially learned the reaction was possible, at least for me, because that shop was next door to, and just downhill from, the local bottled gas supplier. The bozos there would sometimes vent propane cylinders outside (near our fence) before refilling them. The stuff would roll into our shop and stay there, in easily recognized (but evidently non-explosive) concentrations. We tried a number of responses, including a full turn out by the Fire Dept, but they were never able to catch the jerks in the act.

The most effective deterrant turned out to be standing at the fence screaming and throwing stuff. This also felt quite satisfying, what with the teeth-gnashing and all.

;)

BillB

BillB
07-17-2006, 03:14 PM
Acetylene is a mild anesthetic and can make you buzzed if you breath much of it.

Yeah, most solvents/hydrocarbons/etc. can do that sort of thing. I once had an employee whose intoxicant of choice was carburator cleaner. There's no accounting for taste.... 8)

BillB

Millman
07-17-2006, 03:16 PM
[[standing at the fence screaming and throwing stuff. This also felt quite satisfying,]] Yes, Very satisfying indeed! Almost equivelant to {Blowing your own Horn}

Wareagle
07-17-2006, 05:11 PM
The most effective deterrant turned out to be standing at the fence screaming and throwing stuff.

The perfect thing to throw at them would be a lit flare! :D

But then again, you'd burnt your place down, too. Would have served 'em right, though!

Evan
07-17-2006, 05:35 PM
Nah, just walk up to the fence when they are venting and flick an old cigarette butt onto their property as close as you can to the propane. Make like you are going to light another.

Tin Falcon
07-17-2006, 05:49 PM
Ian:
yes do be carefull. There was a professional blacksmith a few years agothatwas using an oxy-propane rig in a bucket lift. There was aparnently a leak. A piece of hot slag ignited the fuel. He was badly burnt from the waste down ouch!!!
Regards
Tin