API Trim 7

[reverman]

For the first Time I have a customer insisting they need a valve with API trim 7.

My question is what grade and how do you Heat treat a 13%Cr material to get it to a 750Hb hardness?

I have some procedures to get 420 in the 500 Hb range but nothing close to 750Hb

 

[bj45]

Hope your customer accepts 750 HB for seating surfaces only, not for the stem.
You mean 420-SS? If yes, check 430-SS.