Summary for e coating application Discussion
E coating application on a carbon steel refrigeration receiver tank was questioned for marine service, including whether the coating is compatible with the steel and how many salt spray hours it might withstand. Mohamed Ali asked if E-coat could be used on the tank and whether it would provide enough corrosion resistance. Khozem Vahaanwala Saify replied that it does not sound like a good application, explaining that electrocoating is still only a very thin paint layer. He said it is certainly compatible with steel and can work well as a primer because it gives 100% coverage, but he cautioned that a thin paint film is unlikely to protect carbon steel adequately in a marine environment. The practical takeaway is that E-coat alone may not be sufficient for this service, and a more robust corrosion protection system would likely be needed.
Q. Hi
1. Can we use E-coat on Carbon steel Refrigeration Receiver tank for marine applications?
2. How about the E-coat compatibility with carbon steel tank?
3. Corrosion resistance in terms of salt spray test hours?
Mohamed Ali
– Bangalore, India
September 24, 2012
A. Hi Mohamed. This doesn’t sound like a good application to me.
Electrocoating is after all only paint, and a very thin layer of paint at that. It’s certainly compatible with steel, and can be a good primer because of its 100% coverage, but I think you’ll need more than a thin layer of paint to keep carbon steel from corroding in a marine application.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
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September 24, 2012
A. Important thing about arresting corrosion is base metal degreasing — perfectly free from oil film & rust (ferric oxide). Second thing is perfect pickling using inhibitors to avoid hydrogen embrittlement and rinse thrice after every operation. Third thing is a manganese phosphating which has the best bonding to any paint/powder coating/CED coating. Hence don’t worry about high carbon/low carbon steel. Concentrate and adopt good pretreatment process is ideal. Follow the technical service data sheet but apply your chemistry knowledge everywhere.
All the BEST,
C PRAKASHAM
consultant – Chennai, Tamilnadu, South India
December 3, 2012
A. Dear Mr Ali,
E-coat is used on Compressors that go into refrigeration and also on the heat exchanger coils since years together.
It can definitely be used on the receiving trays without any issue and will last on this application for about 2 to 3 years. If you want it to go to 10 years then a Top Coat of Powder Coating over the E coat would be an added protection that would work.
Khozem Vahaanwala
Saify Ind
Bengaluru, Karnataka, India
December 28, 2012