Stainless steel threaded fittings are generally used to measure the hardness of Brinell, Rockwell and Vickers hardness indicators.

Vickers hardness

Stainless steel threaded fittings Vickers hardness test is also an indentation test method, which can be used to determine the hardness of very thin metal materials and surface layers. It has the main advantages of Brinell, Rockwell method, while overcoming their basic shortcomings, but not as easy as Rockwell method, Vickers method is rarely used in the steel pipe standards.

Rockwell hardness

Stainless steel threaded fittings Rockwell hardness test is the same as Brinell hardness test, are indentation test method. The difference is that it is measuring the depth of the indentation. Rockwell hardness test is currently a very widely used method, in which HRC is used in the steel pipe standard second only to Brinell hardness HB.

Brinell hardness

In stainless steel threaded pipe fittings standards, Brinell hardness is widely used, often with the indentation diameter to indicate the hardness of the material, which is both intuitive and convenient. However, it is not applicable for steel pipes of harder or thinner steel.

Hardness testing

Stainless steel threaded pipe fittings with an inner diameter of 6.0mm or more, wall thickness of 13mm or less annealed stainless steel threaded pipe fittings can be used W-B75 type Wechsler hardness tester, it is very fast and easy to test, suitable for stainless steel threaded pipe fittings to do a quick non-destructive qualified inspection. Stainless steel threaded pipe inner diameter greater than 30mm, wall thickness greater than 1.2mm stainless steel threaded pipe, the use of Rockwell hardness tester, test HRB, HRC hardness. Stainless steel threaded fittings with an inside diameter greater than 30mm and a wall thickness of less than 1.2mm, use a surface Rockwell hardness tester to test the HRT or HRN hardness. Stainless steel threaded fittings with an inside diameter of less than 0mm and more than 4.8mm, use a special Rockwell hardness tester for pipes to test HR15T hardness. When the inner diameter of stainless steel threaded pipe fittings is greater than 26mm, you can also use Rockwell or surface Rockwell hardness tester to test the hardness of the inner wall of the pipe.