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Galvanised or coated iron metal gets rusty in the coastal area, like Mumbai

As I have seen many times galvanised or coated iron metal get rusty earlier than our expectation. Is there any other solution to keep away from rusty metal like water lines and different structures.

Arun Janardan Ghorpade
consumer - Navi Mumbai, Maharashtra, India
2007

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First of two simultaneous responses --

Galvanized (zinc plated by immersion in molten zinc) object must be conversion coated (chromated or phosphated or treated with some modified silane based product) and then painted. Paint only finished objects must be phosphated,or chromated,or treated with rust converter [on eBay or Amazon] and then painted (primer +topcoat). Good luck!

Goran Budija
- Cerovski vrh Croatia
2007

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Second of two simultaneous responses --

You can try Dacromet 320 coating in place of Galvanizing.

Sanjay Chitlangia
- Gurgaon, India
2007

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October 2013

Hi Arun. The zinc-rich dip-spin coatings Sanjay suggested (there are many brands) might be one alternative, and there are dozens of other alternatives -- including phosphatizing and painting as suggested by Goran. Still, each technology including galvanizing has thousands of shops successfully practicing it ... and the answer to corrosion problems is usually to figure out what may be wrong rather than bounce around from one to the other, especially when galvanizing has more proven longevity in the general case than any alternative. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey