Do quick connects serve as a flashback arrestor?

[Glassroots]

Just wondering if I need to add flashback arrestors to my quick connects? I have been told by welders that they essentially do the same thing but wanted to see what you all had experience with. After reading that recent post about that guys explosive reg I wanted to get some but don't know if I need them. Thanks, J

[Mike_Aurelius]

There are some QD's which have a FBA built into them, but most do not.

Broadly speaking, unless you are using a pre-mix torch, you really don't need an FBA. FBA's can cause problems in low-pressure systems, usually they require a minimum pressure of about 5 PSI.

[Glassroots]

thanks, my red maxes are premix minor. my herbie is a a premix centerfire too, the herbie might have issue with the arrestors.... do you think?

[Mike_Aurelius]

Anything that is pre-mix needs to have a flashback arrestor installed.

[somberbear]

most have check valves which help but no flash back.... very few have those... plumb em in shouldnt have a problem before your step down regulator....

[Mike_Aurelius]

Flashback arrestors are best installed right next to the torch.

[jiminyrootkit]

i could be wrong, but it was my recollection that two types are made. one kind is made to be mounted immediately after the regulator, and the other directly before the torch (sometimes actually attached to it, if i recall).
it may be as simple as what fittings are on which side of the fba, as they are designed to flow one way.
oh, and i would assume that the torch MOUNTED ones are pretty much for welding.
$.02
-f
ps. mine are right under the torch, no reason to burn up a good set of hoses on the way back to the fba if it should ever happen to flashback.

[nafglass]

ps. mine are right under the torch, no reason to burn up a good set of hoses on the way back to the fba if it should ever happen to flashback.

True but I also think it's good to have them at the regs in case a piece of hot glass ever melts a hole in the hose then you're still safe. Your hose shouldn't be in a place that this can happen but you never know.... my 2 cents

[somberbear]

there are 2 jimmy.... problem being is at the regulator you just set you lines on fire....

only reason i say to plumb the propane one in before the step down is cause its a herbie and it would cause flow problems between the step down and the torch that and its not really a common size hose so you would have to order the flash backs and nipples for it...

peace
rob

[Mike_Aurelius]

Typically speaking, a burn through on a hose will not flash backwards up the hose. Because of the positive pressure, it is far more likely to flash outwards instead of backwards.

Installing two doubles the risk of line pressure problems. My suggestion would be for one set at the torch end of the line.

[byron3]

Just wondering if I need to add flashback arrestors to my quick connects?

Yes, but you can buy QC with FBA's as an integral unit.
Here is a primer, hope it answers most / all of your questions :
http://www.applied-inc.com/oxyfuelsafety/Supercat9.pdf

Byron