The dangers of puting chrome plated stuff in a forge

[monstermetal]

Interesting suggestion. I'll talk to my chrome guy next time I'm in there. Thanks!

[eggwelder]

got lead poisoning when i was about 13 or so. we (my cousin and I) were melting lead to cast cannons for a pirate ship model. hits hard and fast. put me down for 2 days.

the next week we finished making the cannons, up wind and arms length from the lead pot. then we took the pirate ship out to the lake and shot at it with .22s till it sank. we still chuckle at the memory. not the lead poisoning part. upwind and arms length still…..

[ptree]

Galvanized when heated in a forge causes the zinc to oxidize to the zinc oxide state and inhalation will give you the "Zinc Shakes", Zinc Flu etc. As far as I can find, unless you have a compromised health situation say CPD, then you feel like you have the flu, and then get better until you dose yourself again.

Hexavalent chrome is another matter, as it is a skin and lung irratant and can cause cancer.

Most Hex-chrome is found in plating solutions and anti-corrosion additives.

In an arc weld, the 5000F or so arc will cause plain chrome to change valance states and become Hex-chrome. Chrome in solution IE alloy steels are not a threat until you first charnge the state to Hex-valent and then also to somehow inhale and cause skin contact.

316 stainless which contains about 18% chrome is used in replacement joints and implanted things like screws used to repair broken bones.

I have not seen anything that says that forging temps release hex-chrome from stainless or from chrome plate. I believe you would have to melt, and then raise to very high temps to cause the valance change.

 

That said, NOTHING that is not normal atmosphere is good for the body. Wear a respirator or use proper local exhaust when welding, grinding etc.Any that goes for welding ANYTHING.

Ptree the industrial safety guy who has worked in automotive parts shops welding zinc coated steels for years and a shop that forged, welded and machined Hundreds of tons of stainless a year.

[IronAlchemy]

Good summary ptree and I concur with your cautions. The only thing that I would add is that the literature that I have read suggest that it is not just the elevated temperature of the arc in welding that causes formation of Cr(VI) but the oxidation of chromium by ozone (O3) which is produced by the electric discharge and UV radiation generated in the arc. The production of Cr(VI) varies significantly with the welding process used (TIG, MIG, stick) but also with the weld conditions including shield gas used.

 

Doug Wilson

Ironalchemy

[Steve Sells]

I've forged chrome alloys with no ill effects, though I rarely heat anything up above orange.

 

chrome alloys are not in the same worry category as chrome plating.

[Dodge]

I welded for many years and while they never really told us that it was bad (nearly all of our product was hot dipped in one of the largest zinc tanks in North America) we took every precaution to avoid breathing the stuff when we would have to re-weld some production error that was too expensive to acid strip and then re-dip. We usually shot blasted the area and set up localized exhaust fans to suck the smoke and gasses away. (We did that anyway when welding black steel) Still, I have tasted that sweet taste the late Mr. Sarver spoke jokingly of earlier. Got a headache once or twice too. I am not advocating making a practice of this but rather stressing that you gotta use some common sense. Don't do it in a close up shop (we worked in industrial sized buildings with 10s of thousands of square feet and ceilings 2 and 3 stories high. (heck, some had their own weather patterns LOL) Do it outside if you must and stay up wind. I'm not saying its absolutely safe then, but you reduce the hazards immensely. Common sense; albeit there does seem to be less of that being dispersed these days

[Stefflus]

I'm with ptree on this one, especially on the respirator subject. Even wood dust will kill you at some point.

 

I asked about this when I worked at the FeCr mill, and although I do not completely trust the answer (and neither should you), the jist of it was that it took electrical arc temperatures to make the hexavalent oxide, or other special circumstances for other compounds. Catalysts, acids, organic chemistry etc.

 

For the temperature range question, we were casting 100 tons of FeCr (70%) at 1600-1800C every 90 minutes with no active ventilation other than the one that took care of the tapping fumes. I wore a simple paper P3 mask, most others were smoking. This might be another matter with pure chrome, but I actually doubt it.

As others have said, plating is more of a sandwich. -Isn't nickel often involved, and isn't that rather unhealthy in fume form?

[arftist]

I'm with ptree on this one, especially on the respirator subject. Even wood dust will kill you at some point.

 

I asked about this when I worked at the FeCr mill, and although I do not completely trust the answer (and neither should you), the jist of it was that it took electrical arc temperatures to make the hexavalent oxide, or other special circumstances for other compounds. Catalysts, acids, organic chemistry etc.

 

For the temperature range question, we were casting 100 tons of FeCr (70%) at 1600-1800C every 90 minutes with no active ventilation other than the one that took care of the tapping fumes. I wore a simple paper P3 mask, most others were smoking. This might be another matter with pure chrome, but I actually doubt it.

As others have said, plating is more of a sandwich. -Isn't nickel often involved, and isn't that rather unhealthy in fume form?

Normal plating is copper then nickel then chrome. Not sure about "hard" chrome, that is an industrial process and could be different.