Polishing 316L SS - products and practices??

Previous company I worked for did a lot of stainless 316 L fabrication & machined assemblies for medical/dental end users, we often finished the assemblies with electro-polishing, in fact it was often specified by the customer, can get down to 4-6 micro inch finishes , make sure whoever is doing it, they know what their doing or they can give you a worse finish than you started with.

I am a design engineer for a company that exclusively uses 316L or 304L to make pharmaceutical process equipment. (you won't find any other steel in our products) If we have to have a polished finish on a surface, we always start with polished plate. It saves time and energy. As far as the polishing, this is almost an art. We have a "master polisher" who trains all polishing employees. He uses various buffing compounds and abrasives. This requires enough detail to fill a book.

I was a Plant Engineer in a pharmaceutical plant, and specified various pieces of equipment, all of which were stainless and with a "mirror" finish, a 2B mill finish would be fine for the outside, but not for product contact areas. Early in my career, I worked for a powder coating manufacturer, there I actually fabricated some containers from stainless. These containers were 2B mill finish, but the joints that I tig welded had to be polished to "mirror" or "cottonball" finish. I tried several methods to obtain the finish, and ended up using a good angle grinder such as a "Metabo", with a "tiger disc", basically a flap disc for a side grinder, which comes in several grits, and can be used progressively up to 400 grit, followed by a polishing disc. The polishing disc I used was a gray almost like a hard sponge, it had the polishing compound already in it, all of these can be obtained at a good welding supply store, if you need part numbers I can search for them for you. The finish is the most labor intensive part of manufacturing pharmaceutical equipment. Hope this helps, just post back to this message if you need part numbers.

Yes Shooter, it would be helpful as a starting point to take to our local suppliers and see what they can come up with.