What is the difference between A193 Grade B8 and A320 Grade B8?

The simple answer is none. The two specifications were written in tandem to be identical. The only difference between the two bolts is intended application. A193 bolts are intended for high temperature and high pressure applications, while A320 bolts are for cold temperature applications. Both bolt grades are made from type 304 stainless steel, have the same mechanical requirements, identical chemical requirements, and same head markings. If you were to hold one of each bolt in your hand, there would be no way to tell which is which, because they are the same.

This also applies to the common A193/A320 stainless grades including B8M, B8 Class 2, B8M Class 2 that we often provide, but also some of the less common grades such as B8P or B8A.

Grade Material Size Tensile, ksi, Min Yield, ksi, min Elong, %, min RA, %, min HBW HRC
A193 B8 304 Stainless All 75 30 30 50 223 max 35 max
A320 B8 304 Stainless All 75 30 30 50 223 max 35 max
A193 B8M 316 Stainless All 75 30 30 50 223 max 35 max
A320 B8M 316 Stainless All 75 30 30 50 223 max 35 max

If you have any questions about stainless steel bolts, please give one of our friendly team members a call, and we’ll be happy to help.

Written

Leave a Reply

Your email address will not be published. Required fields are marked *