If you guys weld after cleaning part with brake kleen? please read this!

[Ednj]

http://www.brewracingframes.com/id75.htm



http://www.brewracingframes.com/id75.htm

[Nick Badame Refrig/ACC]

hi Ed,

So that's what's wrong with me!   Man, everytime I replace a compressor, freon gas migrates in the refrigeration oil and when

I silver solder the lines back together, The freon boils and fumes burn in my torch creating Phosgene gas. It sometimes chokes

the heck out of me.... I think there is a difference here though.. That guy directly burned the liquid hydrocholoride and in my

case I burn the fumes. Maybe not as harmful in my case?? but, I have done this so many times that nobody could possibly count!!

Eye Tink Eyem stll noormal
Nick-

[Sojourner]

That a good one Ed. I too had 2 or 3 very close call of toxic vapor getting into my lung.

Tetrachloroethylene

Tetrachloroethene exposure can be evaluated by a breath test, analogous to breath-alcohol measurements. Because it is stored in the body's fat and slowly released into the bloodstream, tetrachloroethene can be detected in the breath for weeks following a heavy exposure. Tetrachloroethylene and trichloroacetic acid (TCA), a breakdown product of tetrachloroethene, can be detected in the blood.

Thank you for awaken us about this product being use in the wrong condition.

Sojourn for Christ, Gerald

[rv_safetyman]

OK guys, I would like to learn from this. 

We need to clean weld areas when we MIG or TIG, as oil (any petroleum product) on the surface will provide carbon to harden the weld.  Using a wire brush will generally not get the job done, since it was probably used to clean something oily.  I have heard of folks using a stainless steel wire bush, but I don't think that will get rid of the oil.

So, what should we do?  I use acetone or lacquer thinner.  Had not thought of carb cleaner.  Would not have thought about the issue with brake cleaner. 

I guess that lacquer thinner/acetone is the best answer.  HOWEVER, be careful.  We lost a young man when he used lacquer thinner and left the container open and too close to the welding area.   He spent several days in the burn center and lost the battle.

Jim

[kyle4501]

If you use a carbon steel brush on stainless, the brush will leave trace amounts of carbon steel behind & can contaminate the alloy in the weld puddle.

Stainless brushes used on carbon steel & then used on stainless can do the same.

If you're welding both, keep the brushes segregated.


The brake cleaner was news to me. But, I don't usually use solvents - I use a grinder to clean the weld area. . . . (my metal is usually from the scrap pile & more rusty than oily.  )
Gives me something to think about the next time I think about just burning the paint off with the arc.

[Zeroclearance]

I turn a wrench for a living and have seen the formulations for brake wash change over the years.   I only use Ethanol or Isopropyl alcohol based cleaners.   You can get them in 55 gallon drum from companies like Zep.   Very safe until you strike a torch..

I have found out that the cheaper parts store spray cans aren't worth the effort.   

[Jerry Liebler]

Nick,
  I doubt that you have generated any phosgene because of several differences between your situation and that described with the brake cleaner.  1. The freons you deal with are much more volatile and therefore long gone before significant heat hits them.  2.  The temperature of the torch is very much lower in your case, the lower temperature is much less likely to cause the chemical changes.  
None the less you probably should do a nitrogen purge/flush before any soldering/brazing/welding.