Is such a flat washer a high-quality flat washer? -Hardware

What kind of flat washer is a better flat washer? According to the standard, flat washers of 100HV and 140HV grades can be made of low carbon steel. Most companies generally use Baosteel materials when selecting materials, which is convenient for cold stamping. A brief description of the standard is given below. Compared with the BZJ407-1999 standard, 'Tandem Cold Rolled Low Carbon Steel Plates and Strips' and corporate standards have major changes: (1) The grades have been modified and integrated, and the grades have been changed from 8 commonly used to 5 types. St12 changed to DC01; ST13 changed to DC03; St14, St15 changed to DC04; BSC2 changed to DC05; St16, St14-T, BSC3 changed to DC06. (2) The surface quality level has been modified from two to three: Higher-level finishing surface (FB), the surface is allowed to have a small amount of defects that do not affect the formability and the adhesion of coating and plating, such as slight scratches, indentations, Pockmarks, roller prints and oxidation colors, etc. The better one of the two sides of the high-grade finishing surface (FC) product has no obvious defects visible to the naked eye, and the other side must meet the requirements of FB at least. Ultra-high-grade finishing surface (FD) The better side of the two sides of the product must not have any defects, that is, it cannot affect the appearance quality after painting or the appearance quality after electroplating, and the other side must meet the requirements of FB at least. (3) The surface structure is modified from four to two, and the control value of surface roughness is increased. When the surface structure is pitted surface (D), the average roughness Ra is 0.6μm. (4) The regulations on Si and residual elements in the chemical composition of the five brands have been cancelled, and the content of elements such as C, S, and Alt has been modified. Dongguan Hardware Co., Ltd., a manufacturer with rich experience, will bring you a different and extraordinary manufacturer of flat gaskets. We look forward to your choice and win-win cooperation!