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The Advantage of Passivation, Why Do We Need to Passivate and How Is It Done?

I am working in petrochemical plant and some cooling water passivation work is now needed. I would like some information on why should we do it and the how is usually done

Thank you,

Tom Shareef
employed - Saudi
January 13, 2008

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January 21, 2008

Tom,

I would start with reviewing AMS2700 and/or SAE AMSQQP35 [canceled]. After reviewing these documents you may be able to come back with more specific questions relating to your particular situation.

Brian Terry
Aerospace - Yeovil, Somerset, UK

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February 11, 2008

I assume you mean passivation of stainless steel.

In a nutshell, it is removing the free iron from the surface to enable the remaining chromium to form a protective, passive, chrome oxide layer, thereby resisting corrosion. This is achieved with nitric acid or, increasingly, citric acid based formulations.

Ray Kremer
Stellar Solutions, Inc.

McHenry, Illinois