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Purple staining on 316 S/S in high temperature pure steam autoclave

The autoclave uses softened water steam followed by RODI steam. We are getting purple iridescent staining which takes vigorous cleaning with abrasive materials to remove. Client is concerned that surgical instruments may become contaminated.

TONY O'ROURKE
water purification - IRELAND
May 25, 2011

Dear Tony,

This sounds like rouging.
Easy to remove and (partially) avoid with electropolishing.
Kind regards,
Marc.

Marc Quaghebeur
- Diksmuide, Belgium, Europe
May 30, 2011

May 31, 2011

Mr.TONY O'ROURKE,

The purple colouration on stainless steel may by due to inference colouring due the variation in the thickness of the oxide layer on stainless steel.

Your concern is the difficulty in removing the purple colouration.

Many of the metal finisher's concern is to get a uniform col0uration on stainless steel which is highly abrasion resistant.

Please check - your problem may be somebody's opportunity.

Sankara Narayanan.

T.S.N. Sankara Narayanan
- Chennai, Tamilnadu, India
(ed.note Nov. 2017: The good doctor has a fascinating blog at https://advancementinscience.wordpress.com)

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