Oxy/Acy-Use flashback arrestors AND check valves?

[sixdogs]

My Purox Acy/Oxy torch does not get a lot of use and after a few year absence I need to dismantle a big piece of tillage equipment. The torch is in good shape and I bought it new maybe 13 years ago and only use it to cut and heat.
I have flashback arrestors on the tank side of the hoses and that's the only way I have used it. In looking for a tip I found I also have a new pair of Lincoln check valves S24041-15R. For some reason I never put them on and must have had a good reason but cannot recall.
Should I use both flashback arrestors AND check valves or am I good with just flash arrestors? Thanks in advance.

 

[monckywrench]

MSHA encourages protection on both ends, and the arrestors won't protect anything sitting on the shelf. They are "paid for" so I'd hook 'em up.

I run checks at the torch and arrestors at the regulators.

BTW sitting doesn't seem to bother Purox torches. I have some from the 1930s and even the seals are still supple and pass leak checks.

MSHA - Safety Hazard Information - Special Hazards of Acetylene

 

[yomax4]

Flash arrestors for sure. Check valves just stop a reverse gas flow. If 1 tank runs out, The other can easily bleed into the empty one. ( dangerous) If you have no worry of that. It's up to you.

 

[sixdogs]

Well, I do worry so my plan will be to keep my flash arrestors on the tank end and add the check valves on the torch end. I think I understand better now. Any further commentary appreciated.

 

[monckywrench]

The MSHA folks have the greatest incentive to be safe, since explosions underground with no immediate rescue are a Bad Thing. No place to run and all that...

American Welding Society overview:

www.aws.org/technical/facts/FACT-28.pdf

 

[rcowan]

Both.
That was one of the high points of my O/A instructor. I don't know if he had personal knowledge but he sure made a point of repeating his point.

Rc

My Purox Acy/Oxy torch does not get a lot of use and after a few year absence I need to dismantle a big piece of tillage equipment. The torch is in good shape and I bought it new maybe 13 years ago and only use it to cut and heat.
I have flashback arrestors on the tank side of the hoses and that's the only way I have used it. In looking for a tip I found I also have a new pair of Lincoln check valves S24041-15R. For some reason I never put them on and must have had a good reason but cannot recall.
Should I use both flashback arrestors AND check valves or am I good with just flash arrestors? Thanks in advance.

 

[monckywrench]

Protection at both ends can save burning up the hose all the way to the regulator.....

 

[sixdogs]

Thanks, guys. I did go with both check-valves as well as flashback arrestors.
Screwing up acy-oxy doesn't really give a "do-over" opportunity so I took the high road and spent the extra couple dollars .