Alloy structural steel, alloy spring steel

These two types of steel are generally represented by two Arabic numerals at the beginning of the grade to indicate the average carbon content (in tens of thousands), and their average alloy element content (mass fraction) is less than 1.50%. Only the elements are indicated in the steel, and the content is generally not indicated. The average content (mass fraction) is 1.5%~2.49%, 2.50%~3.49%... 22.50%~23.49%, corresponding to 2, 3,... 23... etc. For example, a steel with an average carbon content (mass fraction) of 0.60%, an average Si content (mass fraction) of 2%, and an average Mn content (mass fraction) of 0.70% is represented by 60Si2Mn. For high-grade high-quality steel, the suffix "A" should be added, such as 60Si2MnA. To ensure hardenability, "H" and "vk 20CrMnTiH" should be added at the end of the grade.

Chengxin Pipe Industry is divided into two major sectors: first, leading the high-precision industry - cold drawn precision pipes, and second, adhering to the original industry - high-frequency straight seam welded pipes.