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Corrosion protection without galvanizing
I understand that hot-dip galvanize is the best to reduce corrosion for crs but it is harmful for the environment and very little to nothing available in the Northern California.
How will iron-phosphate conversion and powder coating perform instead?
Or any other treatment of crs for outdoor use to keep corrosion to minimum.
Will greatly appreciate any suggestion
product designer - San Francisco, California, USA
January 27, 2008
I'm not exactly doubting you, Michael. California does seem to be wacko central, and it seems like I can hardly buy a package of anything that California hasn't determined to be carcinogenic :-)
Zinc is natural, common in the environment, and an essential mineral for life (although galvanized coatings can contain too much lead to be comfortable with). Much of the sheet metal on cars is galvanized (and then annealed). Powder coating is absolutely not a substitute for galvanizing because it offers no cathodic protection; but depending on the exposure situation it may be okay. If the powder coating is unikely to be scratched, or if a little rust isn't a big deal, and you don't need a lifetime of decades, powder coating may be an answer. Usually, however, for outdoor exposure you may need more than this, such as an e-coat primer between the phosphate and the powder coating.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
January 31, 2008
February 2, 2008
On what basis do you say that galvabizing is harmful to the environment?
Compared with what? Compared with letting steel rust?
* Some 50% of the worlds steel production is to replace rusted steel.
* Every 90 seconds a tonne of steel turns to rust.
Galvanizing is (in most countries) a process governed by strict environmental standards. It has fully recyclable by-products, produces little or no wastes that cannot be used for something, and protects steel from returning to oxide.
Without the protection galvanizing affords, the environment would be harmed much more than with it.
Whats your basis for claiming that its bad for the environment?
Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK
Good Day
if you need an excellent protection with low price you should make a perfect Zinc phosphating coat followed by PVC Coat or Polyester powder coating
Regards
Yasser Metwalli Osman
Senior Chemist
- U.A.E, Ajman
February 11, 2008
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