Blew up two regs today, WTF?

[Rbeckett]

Installed a fire power O2 reg on the tank, backed off the reg to lower the pressure and cracked the valve. It made sort of a clicking sound while the output gauge spun all the way around and blew off the hose at the torch end. OK, so it has been sitting a while, maybe it just went bad. Go out into the shop and grab another one which is brand new in the package still and swap it out. Click, click, boom same thing happened again. Took it off and installed the original on the tank and it works perfectly. Neither of the regs indicated anything on the tank pressure when I cracked the valve, but the outlet pressure guage went around and didnt go down or move once I got the O2 shut off again. I started both out with the outlet pressure backed all the way down, and cracked the cylinder valve slowly like I have done a million times before. So what is happening with these Firepower brand regs? Anybody know what went wrong and if they are worth getting rebuilt and replacing the gauge? It's definately a mystery to me, so any help or explanation would be great.
Bob

[farmall]

Mystery to me. I'd unscrew the cap on the old one and have a look inside. I'd contact Victor tech support on the new one.

[DSW]

What you describe sounds like a high pressure seat failure to me. It's odd to have two fail in a row, but I guess the odds say it could happen. When you say "new" do you mean new like in recently purchased, or "new" meaning never used before but it had been sitting for a while in the box? If the regs have sat unused for a while I could see the seats going bad just sitting on a shelf.

[Rbeckett]

I think you hit it dead on DSW. They have been in my shop sitting unused for three years and the new one in box had been sitting closer to 5. I guess it truly is a use it or lose it deal on regs. Either way it is good to know or have a good idea of what happened. Thanks guys!!!
Bob

[RodJ]

:eek: If you call Victor, I'd be interested in knowing what they say, mostly so if I ever replace or am asked for a recommendation to replace regulators, I don't have to repeat this story about the Firepowers. Glad no one was hurt.

I will now go home and stare intently at a pair of old 2 stge Airco regulators I bought NIB and put on the shelf. I mean, just STARE at them so they know I am on to their tricks and see if they flinch.

[farmall]

I've had OLD Firepowers sit and work fine, but who knows if the innards have been changed over the years?

When in doubt, get industrial gear, be it Victor, Smith, or ESAB/Purox/Oxweld. I've had old, beat up 450/460 regs which had sat for years (got 'em in an auction lot) work fine, but those have a different seat and a stainless steel diaphragm.

[lotechman]

You wouldn't be using the larger high pressure oxy cylinders???... they are over 3 K pressure when full.

[davo727]

I have blown 2 argon regulators in 5 minutes before. Then I had the local weld shop send them off and rebuild $45 each I think

[Oldiron2]

Isn't there usually a relief valve between the two stages which is supposed to let go before the low side's maximum pressure is exceeded? I haven't looked at any of mine in a while, but isn't that how most are plumbed? What kind of fittings were on the hoses where they came apart?

[farmall]

Oxygen regs have blowoff valves. I've not seen an acetylene reg with them as it would be quite dangerous.

If the first regulator poppet stuck it could overpressure the hose before the blowoff opened. Afterwards, it was "unstuck".

Firepower regulator with blowoff at the five o-clock position.