Everyones welding instructor has told them this, But ALWAYS face away from high pressure tanks on your torch or welder when opening them. Yesterday I opened the tank on my Tig (slowly,as always) and the regulator failed catastrophically.....Parts flew all over the shop. No injury...But it got my attention. Jerry
I've said it out loud, I've mumbled it under my breath, I've thought it without saying it -- but "Safety is Cheap!" Do it the safe way, the right way, no matter whether it takes a minute longer. It's worth doing it safely. Good story, Jerry. Glad you're not hurt.
Jerry,
You are the first person I have ever heard this actually happening to. I alway take this precaution but was not sure how much merit i should give to this act. I'm glad to know that I was not wasting my time all these years. Thank the Lord nobody was hurt.
Very old topic:
Throw away all brake cleaner more than a couple years old. The early version created nerve gas when welding. All the new stuff is safe. The old chemical could cause permanent brain damage with a single wiff.
I had an in line air filter on a sand blaster blow off a few years ago, just after I opened the valve.
I had just opened up the air valve to the sandblaster and heard a rapidly rising air leak from the area of the tank fittings and in line filter.
I turned away from the rig just as it blew the bottom of the inline filter off the air filter housing splattering bits of the filter housing all over the ground just a few inches from my feet.
I could have had a serious foot injury or if things had blown a different way, shrapnel injuries as things came apart.
Makes you respect even compressed air devices.
Larry
Trouble;
Yes, brake cleaner (among other things) exposed to fire will create dangerous gas products but all the brake cleaner I've ever used evaporated so quickly that it was extremely unlikely that it would be a problem.
NHRA banned use of Brake Clean, they have a new allowed one for the racers to use.
DON'T EVEN THINK THAT WAY Neil. I had a very close call several years ago where I sprayed a body seam on an E-Type Jag and went to weld it over an hour later. I thought my lungs were going to be torn out. Luckily for me there were no lasting effects because others who have had no larger dose have had life altering results.
Pete
Yes Neil, The residue will generate the dangerous gas when welding if using the wrong stuff. I've heard some real horror stories from this. We did find some stuff that will not cause this problem. We coat (arc process) parts cleaned with brake cleaner all the time now with no problem. Just got to be sure you have the right stuff. If any doubt, don't use it.
Thanks, Guys--
I guess I've never gotten hold of the bad stuff or I've waited long enough (usually a few days) for the stuff to evaporate fully. I'll certainly take your advice from now on.
I wonder how many times in the past that I've dodged a bullet by sheer luck?
If the label says chlorinated, it's the dangerous stuff. It makes phosgene (sp) gas when heated.
If it says non-chlorinated, it's the new stuff and safe.
Ron
Ron, I believe you're right but if you've ever gone through the experience you won't take any more chances. It's back to old fashioned solvents followed by pressure washing for me. I'm a guy who tends to get put off by a lot of these carcinogenic scare tactics and generally ignores them in favour of the "old fashioned", "dangerous" ways but my brush with brake cleaner has made me overly cautious with that one. I still use brake cleaner, but only for things I'm not welding on.
Pete
Victoria just got hit by a big wind storm, we were nailed a few days ago, and there seem to be problems all over. Be careful when you are cleaning up. One of our trees fell over the electrical line feeding the neighbor's house. I was out in the rain cutting it off of the line and working with a saw in one hand and using the other to grab limbs.
Not good. I was standing on a limb, slipped, and ran the saw close to my bird finger. It easily could have been a lot worse.
The important thing is to be calm and careful. This is hard to do in the rain and wind so it is a good idea to let the storm blow over before starting to work.
We wait till the hurricane passed so we can get more beer then fire up the saws. :wink: Glad it was a near miss.
Quote from: Peter Jack on September 03, 2012, 02:09:41 PM
DON'T EVEN THINK THAT WAY Neil. I had a very close call several years ago where I sprayed a body seam on an E-Type Jag and went to weld it over an hour later. I thought my lungs were going to be torn out. Luckily for me there were no lasting effects because others who have had no larger dose have had life altering results.
Pete
You guys are actually missing out the reaction actually works...
It's actually a cobination of heat, the UV of the arc, and C02 shield gas. First the heat breaks down the solvent into smaller chemicals. The UV allows part of those chemicals to pick up a freeradical which then causes it to combine with the CO2 gas to make Phosgene. It;'s a really interestingly complex chain of events that is needed.
FYI lots of things when heated can make phosgene, several thermoresin plastics, some rubbers, and even a few food grade materials under the right conditions. It's a very simple chemical, and was produced during the second world war with nothing more than chlorine gas and carbon monoxide with activated charcoal as a catalyst. It's one of the most stupid easy deadly compounds to make we've ever discovered.
Also I've seen it called nerve gas and nerve agent in this thread. It isn't. The affects on the nervous system are due to lack of oxygen, which can of course be permanent. It's more along the lines of being strangled to death. Nerve agents work in a wholy different and ugly manner.
Floydjer, regarding your original post that started this thread . . .
1. I'm glad you weren't seriously injured in the incident.
2. I'm a HUGE believer in eye protection in any kind of shop.
3. Having been a weldor (not a spelling error) for decades, one of
my habits, after closing the main valve of a high-pressure cylinder
(for example, when done welding for the day), is to bleed gas from
the hoses that feed the equipment (i.e., torch). Then to unscrew
the pressure adjustment knobs of the regulators, until the "output"
gages read zero pressure. This can help to ensure that no sudden
blast of gas gets too far when the main valve of the high-pressure
cylinder is opened (slowly is good) the next time. I think this
practice may also protect the regulators themselves, as well as
everything downstream (hoses, fittings, torch).
Quote from: tallguy on January 12, 2016, 11:41:13 PM
Floydjer, regarding your original post that started this thread . . .
3. Having been a weldor (not a spelling error) for decades, one of
my habits, after closing the main valve of a high-pressure cylinder
(for example, when done welding for the day), is to bleed gas from
the hoses that feed the equipment (i.e., torch). Then to unscrew
the pressure adjustment knobs of the regulators, until the "output"
gages read zero pressure. This can help to ensure that no sudden
blast of gas gets too far when the main valve of the high-pressure
cylinder is opened (slowly is good) the next time. I think this
practice may also protect the regulators themselves, as well as
everything downstream (hoses, fittings, torch).
Excellent practice Tallguy.
Incidentally, and to no surprise, that is precisely the procedure that they teach in college level welding classes . . . . .
And in welding certification classes . . . . .
And what welding regulator mfg's recommend . . . . . . .
The amount of gases "lost" is cheap insurance against a "disaster". I've witnessed a welding accident . . . . . don't want to see another.
:cheers:
Fordboy
This bit of advice may help very few people, due to the rarity of the circumstance(s), but I'm sharing it because it was a
close call for me, and except for the fact that I was wearing eyeglasses, I could have been quite seriously injured or even
blinded.
I was doing some electrical work on 208V single phase wiring for a shop, and wanted to test continuity of a circuit. But I
didn't have a voltmeter. I did have various wires, and a utility light (sometimes called a "drop light") that included a regular
"household" lightbulb. I knew that 208V would destroy the filament of the bulb, but seeing the flash as this happened would
confirm for me continuity. And a lightbulb like that isn't expensive. Well, as soon as I turned it on, the entire lightbulb
exploded violently, launching shards at me (including my face). Apparently this voltage not only melted the filament but
vaporized it to the extent of generating sufficient pressure to shatter the glass bulb. I suggest people never do anything
similar to this (i.e., using a 12V bulb to test continuity of 115V circuitry).
I used to work for a large vehicle manufacturing plant. One of the rules was that all employees had to wear steel-toed shoes
or boots. In the three years I worked there, I only failed to follow this rule on ONE particular day. And of course, that was
the day that I dropped a heavy steel pipe onto my toe, crushing it (and possibly crushing the bone also).
This is about electrical safety.
There's an old habit that people should get into when working with more than about 12 volts of electricity: Don't use both
hands at once when touching anything that can conduct electricity. Some people even keep one hand behind their back, or
in a pocket. Here's the reason, for those who don't yet know this. Electricity will follow the path of least resistance. And
guess what? Blood, being salty, is an excellent conductor of electricity! 115 volts is plenty enough to penetrate human skin
and send current from one of your hands through your blood and your heart, stopping it immediately. You may not know
this, but the heart is a muscle, and runs on electricity . . . just like the frogs' legs that Galvani experimented with. Exposing
only one hand at a time to anything electrical can greatly improve your chances for the electricity -- if you are shocked -- to
only pass through your hand, instead of your heart. Yes, I've been shocked several times in my life, only through the hand --
and even that is no fun. Please do be extra-careful.
Not long after Nancy and I got together I made sure she understood that electricity makes muscles contract, and therefore:
If I'm working on electricity and contact bare wires and I'm getting shocked - - PUSH me away, don't PULL me. Shove, bump, knock my legs out from under me so I fall - - - get me away from the wires without you getting caught if and when YOUR muscles contract.
" Don't use both hands at once when touching anything that can conduct electricity."
Amen to that. This was one of the first things we learned at Ft Monmouth in the radar school. The magnetron had 20,000 volts on it. You only needed one zap from that.