Acetylene Regulator Safety

R

Russ Koch

Member
Hi guys, I experienced a problem with a Hobart "medium duty" acetylene regulator that I think is VERY serious! After owning the set for a year one day in May I needed to use it and found it to be leaking from the vent hole below the adjusting screw!!!! Thank God it was a nice day and the garage door was open. I lost about 100-150 lbs in less than a 1/2 hour before I realized what was happening! Been talking with Hobart and at first were real concerned, but then I was the only one complaining AND the production manager(who I was communicated with)didn't have the tools to take one apart??? Nor did he have one to take apart! Because I found out(the packaging won't tell you) they are now made in China! The problem is the rivet/fastener in the center of the diaphragm is improperly peened/crimped and is done so off center allowing it to eventually leak. So I say to the rep."you outsourced to China and you have NO idea of quality, but your saving money" his answer:"oh no Russ, we had other reasons other than that.
I tried to work with them, for 5 months, but they like other corporations, it's only money. SAFETY? What is that???????
Hopefully you guys can spread the word. What happened to me,scared the hell out of me! If that door had been closed at the time?????
Another reason to buy American! And it's NOT Hobart!
 
I've used cylinder gasses since the late 60's and have had many regulator diaphragms pop, jamb, and leak, both on single and dual stage USA made regulators. Nothing is ever 100% despite the level of design engineering or manufacturing prudence. Just ask NASA. It all comes down to basics- rules of cylinder safety. A cylinder in any unventilated area is a bomb. I've seen untrained fooles open acetylene cylinder valves more than a 1/4 turn- all the way like a double seat oxygen valve, and then take the T wrench off the cylinder and loose it. Always be vigilant, good thing you were. Hopefully you weren't using that setup to chop, section, and channel an A.:eek:
 
What is really cool is a acet tank in a garage fire.

Guy working on late 60's conv in his garage.

Wrenches placed on top of battery, can of gas to pour down carb. Knocked over can of gas on battery and jumped to stop it. Garage fully involved when I drove up with ambulance, he was burned pretty bad.

The acet tank was venting with this 10 foot blow torch straight up in the air. It has really stuck in my mind since. In all this flame you could see the blow torch blowing hard straight up. All this in the few fleeting moments I looked at the fire as I grabbed this poor guy in major pain and worked on getting him on the stretcher. Funny the things that stick in your mind.

Garage is now a concrete pad.
Car is gone.
Guy spent some time in a burn unit after a helo flight and recovered.
 
If that room had filled with gas it would explode hitting a light switch. The house would have been gone and maybe the neighbour's house too. I kid you not.

I nearly got expelled from highschool after igniting an "acetylene bomb" in the metal shop at lunch hour.
It was a very small nacho chip bag which I filled through a hole in the side with gas for about 5 seconds only
(I just wanted to try a SMALL bang first) :rolleyes:
...baby what a big surprise!
When I passed the lit torch by the hole there was a 2 foot ball of flame and I swear the walls musta bulged outwards from the blast:eek:
Lucky for me it was on a lunch break. Every student on the grounds was talking about "the explosion" but there was only one substitute teacher on and we somehow managed to convince(beg) him to clam up :o:o
 
Craig Lewis said:
If that room had filled with gas it would explode hitting a light switch. The house would have been gone and maybe the neighbour's house too. I kid you not.

I nearly got expelled from highschool after igniting an "acetylene bomb" in the metal shop at lunch hour.
It was a very small nacho chip bag which I filled through a hole in the side with gas for about 5 seconds only
(I just wanted to try a SMALL bang first) :rolleyes:
...baby what a big surprise!
When I passed the lit torch by the hole there was a 2 foot ball of flame and I swear the walls musta bulged outwards from the blast:eek:
Lucky for me it was on a lunch break. Every student on the grounds was talking about "the explosion" but there was only one substitute teacher on and we somehow managed to convince(beg) him to clam up :o:o
Click to expand...

Ah, the good old days. I had to give a presentation in Spanish class (in Spanish) and at the end of my presentation I set off a smoke bomb (it fit with what I was talking about--don't ask). I got in trouble, but not suspended or expelled. These days you're asking for a trip to Guantanamo with a stunt like yours (or mine). :mad:

Back on topic: I've also noticed recently that a lot of disposable tanks (propane, MAP gas, etc) that I use for small jobs leak when you take the torch head off. I guess they don't make much of anything like they used to.
 
A leaky regulator is also a good way to destroy the unbreakable hi-lux 4WD. There was one in Australia where a tradey left his bottles on in the back of his tray with a canopy top. He thought it was good enough that the torch was off. It leaked over night filling the hi-lux with accetylene, in the morning when the door was opened, the interior light was enough to ignite the gas and up it went. He was very lucky not to be killed. This also emphasizes another safety tip, turn the bottles off when not in use, even if it's only for a short time.
The story is about half way down on this report;
www.ballarat.edu.au/vfed/manufacturing/ssc/docs/Newsletter28.pdf
 
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Anybody have a recommendation for a good book on gas welding?? It can be new or ancient...I am a librarian and a good bookhunter.
Most of the modern books I have found give a very inadequate space to acetylene and focus almost entirely on MIG and TIG.
 
An incident happened up here in the north, with a professional pressure welder and his welding truck that was well publized at the time. It was common pratice for the welders to store their hoses and torches in steel cabinets on the truck bed, usually locked. The welders helper forgot to shut off the bottle valve the day before when when done for the shift. Regulator adjustment was left on. Hoses were neatly coiled on the hanger in the cabinet and locked. Valve on torch vibrated open a small amount releasing acetylene into the cabinet. Oh!.....I forgot to mention, the weather at that particular time was a balmy -30 degrees below zero. The next morning after arriving at the job site, the welder was unable to open the lock on the cabinet, due to ice in the mechanism. He took out his butane lighter from his pocket to un-thaw the lock on the cabinet.......BOOM ! Further details not required. Very messy !
Check and re-check those tank valves and regulators.
 
Beware also of innocent looking little peopane torches. While using one in a small room with many flamables, there suddenly developed a fireball 3 feet in diameter! Luckily there was a large CO2 extinguisher very close by, which worked. (and it hadn't been inspected in years, negligent of me, a possible catastrophy waiting to happen, and a real boo-boo in and of itself). The valve on the torch had developed a sudden leak which ignited instantly. So, if anything about the operation of your torch seems a bit funny don't take chances, replace it.
 
Not from personal expierience, but...............I have heard that the small "Bic" lighters are bombs, if to close to welding or cutting torches and get hit.
 
In high school the hose behind the torch caught fire. No damage done. Thanks for the tip on not opening the gas valve all the way. I don't recall that I was ever told that. Now if I could get my co-worker to vent the hoses when he is done.
 
redmodelt said:
In high school the hose behind the torch caught fire. No damage done. Thanks for the tip on not opening the gas valve all the way. I don't recall that I was ever told that. Now if I could get my co-worker to vent the hoses when he is done.
Click to expand...

Just a quick note here-

High pressure Oxygen cylinder valves are of back-seat design and must be opened all the way to tighten to the second seat, preventing leakage along the valve stem. NEVER use an O2 cylinder with the valve partially open.

Acetylene valves are of standard stem pack design and should be opened only 1/4 turn, which is sufficient for even the largest cutting tips. If the cylinder has no valve bonnet (hand wheel) the stem wrench must be left in place and tethered to the cylinder for quick emergency access. NEVER open an acetylene valve farther than a single twist of the wrist!

Proper shut and bleed down: Firmly close both cylinder valves first, before turning down the regulator adjustments. Crack both torch valves to bleed down gas until both the high and low side gauges read zero. Now back off the regulator adjusters until loose. Close the torch valves and wait several minutes. If all four gauges remain at zero, all is OK. If a high side gauge creeps up, the cylinder valve is not closed tight or is defective.

Thank you Mr.Ted Gorny, my 1965 high school welding teacher.
 
If I have been using the torch I like to shut off the tanks 2 or 3 times. Just to be sure. I know we cannot all be safe but we can all be cheap. I am not interested in paying to refill a cylinder I do not have to.
 
The welding supply store in Watertown, S.D. has a picture of a mid 50's Chevy that the owner put an acetylene tank in the back seat to haul it home. He left it in the car overnight and the valve had a leak. Sometime during the night when the car's electric clock contacts made a spark during the rewinding of the clock spring it set off the explosion. There wan't much left of the car.

When I worked at the salvage yard about 12 years ago a couple guys out back filled a large black plastic garbage bag with acetyline and oxygen, then poured a gasoline trail from the bag to a spot about 30 feet away. When they lit it the entire neighborhood shook and within a minute about a half dozen fire trucks and cop cars were there to see what happened.
 
Tom,that was a lesson my welding teacher gave us in 1974.He filled a paper grain sack,(no plastic garbage bags then)with acetylene,then place it in the middle of the parking lot with an ignitor he had made for his lesson.He made a fireball like you see in the movies.He was big on real life examples that you would remember,not just tell you what could happen.He said this is what you will see if you leave a valve open and a part develops a leak.All my life when I walk by a set of bottles I reach out and make sure they are shut off.My old boss used to tell people,watch Keith when he gets near the torches.He will test the handles every time.While I was taught to do it,I never purge and drain the hoses and crank back the regulators.I may use the torches ten or a dozen times in a day,I open the valves,heat up a nut,shut them down,and may or may not do it again in ten more minutes.I also have 75 feet of hose and I am not draining that every time.I do have anti-flashback valves on my regulators.
 
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