STAINLESS SEAMLESS PIPE

Hardness :

Stainless steel tubes are commonly used to measure the hardness of Brinell, Rockwell and Vickers. Brinell hardness Among the stainless steel pipe standards, Brinell hardness is the most widely used, and the hardness of the material is often expressed by the indentation diameter, which is both intuitive and convenient. However, it is not suitable for steel pipes of harder or thinner steel.

Rockwell hardness:

The stainless steel tube Rockwell hardness test is the same as the Brinell hardness test. The difference is that it measures the depth of the indentation. The Rockwell hardness test is a widely used method in which HRC is used second only to Brinell hardness HB in steel pipe standards. Rockwell hardness can be applied to the determination of metal materials from extremely soft to very hard. It compensates for the Brinell method. It is simpler than the Brinell method and can directly read the hardness value from the dial of the hardness machine. However, due to its small indentation, the hardness value is not as accurate as the Brinell method.

Vickers hardness

The stainless steel tube Vickers hardness test is also an indentation test method for measuring very thin metal materials and surface layer hardness. It has the main advantages of Brinell and Rockwell methods, and overcomes their basic shortcomings, but it is not as simple as the Rockwell method. The Vickers method is rarely used in steel pipe standards.

Hardness test

The stainless steel tube has an inner diameter of 6.0mm or more and an annealed stainless steel tube with a wall thickness of 13mm or less. It can be a W-B75 type Vickers hardness tester. It is very fast and simple to test and is suitable for rapid and non-destructive inspection of stainless steel pipes. Stainless steel tubes with an inner diameter of more than 30 mm and a wall thickness greater than 1.2 mm are tested with a 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. For stainless steel pipes with an inner diameter of less than 0 mm and greater than 4.8 mm, the hardness of HR15T is tested by a special Rockwell hardness tester for pipes. When the inner diameter of the stainless steel tube is larger than 26 mm, the hardness of the inner wall of the tube can also be tested by a Ro