For example: 120HBS10 / 1000130: 10mm diameter steel balls expressed in 1000Kgf (9.807KN) test force, maintain 30s (seconds) measured Brinell hardness value 120N / mm2 (MPa) B, Rockwell hardness (HK. ) with Rockwell hardness test Brinell hardness test, are indentation test method is different, it is the measure of the depth of the indentation. That is, in the early Yong test force (Fo) and total test force (F), has the role of stainless steel pipe, the pressure head (gold steel cone or ball) onto the surface of the sample, the delineation of keeping time, removing the main test force, calculated by measuring the residual indentation depth increment (e) hardness value. The value is an anonymous number to sign HR said that, the use of the scale there are A, B, C 316l stainless steel tube, D, E, F, G thin-walled stainless steel tube, H, K and other nine rulers which used to 316L hardness test scale stainless steel pipe generally A, B, C, i.e. HRA, HRB, HRC hardness value calculated using the following equation: When using the A and C scale test, HR = 100-e when the B scale test at 304 pipe, HR = 130-e where e-- residual indentation depth increment, which even the Department to designate units of 0.002mm show that when an axial displacement of the indenter unit (0.002mm), that is equivalent to Rockwell hardness change a number. Jinding stainless steel pipe factory of stainless steel pipe heat exchanger Why? Stainless steel tube heat exchanger is the most widely used austenitic stainless steel, the alloy grades for OCr18Ni9 (304) and 00Crl8Ni10 (304L) are two, accounting for more than 80% of austenitic steel output. Because of the heat exchanger with stainless steel tube is not long history of large-scale use, private, family, normative standards are not perfect, therefore, currently on the market for stainless steel pipe used in the power industry, according to the majority of foreign brands and the technical requirements of production. Stainless steel pipe shall be flattening test. During the test, the weld should be at the position perpendicular to the direction of the force, the non-annealed stainless steel tube to the outer diameter of 2/3 of the pressure, the pressure after the heat treatment to the outer diameter of the stainless steel tube 1/3. After flattening the outside of the bend shall not crack or split. Inner and outer surfaces of the stainless steel tube should be smooth, without cracks, cracks, folding, prevent the use of heavy leather and other defects. Wrong side, undercut, bumps and other defects shall not exceed the thickness tolerances. Weld defects may be repaired, but after heat treatment delivery should be re-heat-treated steel patches. Shandong Jinding Stainless Steel Pipe Co., Ltd. specializes in the production of stainless steel heat exchanger tube, is a professional production of stainless steel pipe manufacturers, quality assurance, delivery, can be customized according to customer requirements. Sanitary stainless steel pipe _ Jinding Industry (certified) _ stainless steel tubes supplied by Shandong Jinding Stainless Steel Pipe Co., Ltd. Shandong Jinding Stainless Steel Pipe Co., Ltd. (www.jdbxg.cn) is Dezhou, steel leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Jinding tube industry leader in the staff warmly welcome all inquiries negotiations to create Jinding Pipe a better future.