Pickling & Passivation

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Here is "how to"

http://findarticles.com/p/articles/mi_m3101/is_5_76/ai_109028306/pg_6/

milo

Thanks Mr Milo

You're welcome.

I was trying to find a copy of the article my colleague wrote, but it seems to be hiding. This was relevant. Welcome to CR4!

milo

Pickling is a process by which a material is treated in a combination of chemicals, usually acid solutions, to remove oil, grease, dirt, muck, rust etc and is not necessarily specific to SS. However, the solution used would be something specific to SS e.g., a 10% soln of HCl + HF. Whereas passivation of SS means developing the corrosion resistant layer of Chromium Oxide (Cr2 O3) on the surface of an SS material by treating with Nitric Acid solution. The excess acid should be washed off.

So acid pickling removes oil and grease?

have a look at this doc, there is an introduction that explain the difference between descaling, pickling, passivation and cleaning:

http://www.euro-inox.org/pdf/map/Passivating_Pickling_EN.pdf

and also these other docs are useful

http://www.google.com/cse?cx=010231287511253103195%3aqmfpcvv02be&cof=FORID%3a1&q=pickling+passivation+stainless+steel

S

corrosion prevention & control