How to test the hardness of stainless steel seamless pipe?

At present, the hardness of stainless steel seamless pipe is generally measured by three hardness indexes of Brinell, Rockwell and Vickers. What is the specific situation?

1. Annealed stainless steel pipe with an inner diameter of 6.0mm or more and a wall thickness of 13mm or less can be tested by W-B75 Wechsler hardness tester. It is very fast and simple to test and is suitable for rapid and non-destructive inspection of stainless steel pipes.

2. Stainless steel pipe with inner diameter greater than 30mm and wall thickness greater than 1.2mm, using Rockwell hardness tester to test HRB and HRC hardness. Stainless steel tubes with an inner diameter of more than 30 mm and a wall thickness of less than 1.2 mm are tested with a surface Rockwell hardness tester to test HRT or HRN hardness.

3, stainless steel pipe with inner diameter less than 0mm and greater than 4.8mm, using the special Rockwell hardness tester for pipe, test HR15T hardness. When the inner diameter is greater than 26 mm, the hardness of the inner wall of the pipe can also be tested using a Rockwell or surface Rockwell hardness tester.