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Ted Mooney, P.E. RET
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Corrosion protection of soft aluminum tube in 44% salt water concentration??
I need to protect soft aluminum tubing that sees minimal pressure (less than 100 PSI) but sees saltwater concentrations of 40 to 44%. This exposure is half atmospheric air/ half salt water. The tubes are heated with steam to a maximum temperature of 249 F. Can any version of anodize provide 1,000+ hours of protection for these tubes?
refrigeration designer - La Crosse, Wisconsin, USA
November 29, 2011
No way. You need a thin hex chromate conversion and powder coat.
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Robert H Probert
Robert H Probert Technical Services
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Garner, North Carolina
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November 30, 2011
It might prove a little difficult to Powdercoat the internal tube surface?
William DohertyTrainer - Salamander Bay, Australia
December 3, 2011
Hi, William.
I assumed that the steam was inside the tubes, and the outside was exposed to a mix of air and salt water, but Indeed it isn't clear whether the inside or the outside of the tubes is exposed to the air and saltwater.
Regards,
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
December 5, 2011
December 7, 2011
Well, I guess my initial response was a little tongue in cheek.
Obviously the internal tube surfaces could be coated if they were straight initially and formed post coating.
A difficult, but not impossible, process though it may be.
If this was the answer, then the next question would be what Powder?
I would think a Fusion Bond Epoxy over the Chromate?
Regards,
Bill
Trainer - Salamander Bay, Australia
December 16, 2011
I have a similar application where I need to resolve corrosion also.
I am using tooling of SS316, which is dipped in a saline solution to 500° C.
Our intention is a titanium plating to extend the productive life of my toolings is that possible or do you have a better option?
- Guaymas, Sonora, Mexico
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