Freaky faulty oxygen tank

Hi all,

I was doing a little soldering Sunday night and noticed the oxyen
pressure had gone from about 5 psi to around 20-30. I closed the
oxygen tank value, bled the line, and then noticed that even with the
tank valve shut as tight as it would go, the pressure was still
rising slowly.

My torch is a Meco Midget which developed problems almost
immediately with its Uniweld propane regulator, which had to be
replaced. So at first I thought it was the oxygen regulator’s turn
to go. But with the tank firmly turned off, there should have been
no more problem, unless the tank itself was leaking.

The oxygen tank was recently filled (i.e., swapped out) and
originally read around 2000. Within an hour, it had gone to zero. I
kept bleeding the line because I didn’t want there to be a problem on
the hose end.

I’ve never run into this before, so do you agree that it was a
faulty tank? Or could it possibly be the fault of the regulator? I
can’t see how, as nothing should have been happening when the tank
was shut down.

Mona

Mona,

I only have experience with single-stage regulators, so I’m not
entirely sure about your situation if you have dual- or
triple-stage. Mine are from Smith, and both Oxy/Propane regulators
behave basically as you describe. Once I close the tank valve on
either gas and bleed the line, the pressure increases slowly until
just before the line bleeds completely, where they then drop off
immediately.

Safety first: If you just aren’t sure, or your regulators are
definitely behaving differently from how you remember, take them
immediately to a welding supply that can test them. If your local
supply can’t test them or you don’t have a welding supply store
nearby, return them to the manufacturer immediately. Your body may
be glad you did.

James in SoFl

I've never run into this before, so do you agree that it was a
faulty tank? Or could it possibly be the fault of the regulator?  I
can't see how, as nothing should have been happening when the tank
was shut down.

Yup. I just had a similar one with a tank swap. It leaked around
the valve packing. It only leaked when the valve was open, so I had
to remember to close the tank when I wasn’t actively using the
torch, the following Monday, I took it back to the supply house.
They checked it with leak bubbles, and handed me another tank.
They do wear out, eventually.

Ron Charlotte – Gainesville, FL
@Ron_Charlotte1 OR afn03234@afn.org

hello Mona, Don’t fool around with this. Immediately bleed the
pressure off the hose by opening the valve on you torch and
disconnect the regulator from the tank. After that, come back and
finish this note. Several things could be wrong but if you turn off
the valve at the tank and the pressure keeps going up, then there
must be a faulty valve on the tank. If it goes to 20 lbs, then it
could go to a thousand. Just call the oxygen company and let them
deal with it. good luck.

Tom Arnold

Mona, this sounds to me like a leaky and faulty valve on the tank. I
would most definitely take it back to the dealer for a refund and/or
replacement. Leaky O2 can be dangerous in areas where flame may be
present. Back in the 60’s an American spacecraft was destroyed and
the astronauts in it died because they were in a predominantly O2
atmosphere and there was a short in the wiring. (Apollo 8 I think?)
The oxygen greatly accelerates burning and can be a real bear if
something does catch a spark. Be safe and take it back.

Mike