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Finish standards for stainless steel

 

We are a small fabricator of item made from stainless steel sheet. The grades of the "brush" finish are a problem. Supplier A's #3 finish is not close to the #3 finish from supplier B. Same with #4. The materials are type 304, type 304L, and type 316L.

Many modifications or additions to equipment would be improved if I knew more about this subject.

Who sets the standard and where are they?

Mike Butler
restaurant equipment - Lake Worth, Florida

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Hello Mike!

The finish designations are standardized by the American Iron and Steel Institute, an industry consortium, and are spelled out in several publications. Surf on over to the Nickel Development Institute, click on the Technical Literature pointer, and use the search option to find publication number 9012, "Finishes for Stainless Steels". They will send it to you for free because they are nice folks and because they want to spread the word about their favorite element. While you are there, make sure you order #9014 "Design Guidelines for Selection and Use of Stainless Steel", and #9006 "Wear and Galling Characteristics of Stainless Steels". Also free. Gotta love that price.

Another good reference for your library is the AISI Steel Products Manual [affil link on Amazon], now published by the Iron and Steel Society, it is worth it if you are dealing with stainless steel.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York
 

Please note that ASTM A480 also lists stainless steel sheet finishes. Paragraph 11 lists the type of finishes and note 4 is an explanation of sheet finishes. I was the chairman of a Task Group that revised these finishes a couple years ago. I agree that different producers and/or suppliers have somewhat different looking finishes. That is a difficult characteristic to make exactly the same using different equipment.

James L. Klich
- North Canton, Ohio