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Stainless steel finishes for chemical reactors (emulsion polimerization reactors)

Hi all,

I am a PhD student and I would like to know which finishes are used in Stainless steel chemical reactors (specifically in polymer emulsion reactors), I mean, if is possible for a company to have a reactor electropolished, or if always is 2B finish or what is, cause really I am not able to find it.

I am chemist, not engineer, so if someone could tell me which standards I could read (cause I see in internet some webs that talk about ASTM etc....). I know is not a trivial question and there is not a unique answer, but maybe we could say that typically for example 2B is chosen, or which is the criterion for the election of the finish.

Thanks in advance and have a nice day!

Jone

Jone Fernandez
pHD student - Spain
March 1, 2011

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Dear Jone,
In these polymer emulsion reactors and heat exchangers, you want to avoid polymerisation and build up of the product.
Therefore you need a smooth and "micro-deburred" surface.
The Stainless Steel used for construction is mostly 2B or mechanically polished to a roughness Ra below 0.6 ëÊm. Then you have to electropolish your reactor to realise the smooth, easy to clean, non-stick surface. The final roughness Ra after electropolishing will be below 0.4 ëÊm. But it is not the roughness that counts, it is the smooth, micro-deburred surface that gives the non-stick properties. In this application, it is better to have an electropolish surface with a Ra 0.8 ëÊm than a non-electropolished surface with a Ra 0.4 ëÊm.
Kind regards. Marc.

Marc Quaghebeur
- Diksmuide Belgium Europe
March 3, 2011