1. ASTM A193/A193M-2019 "Alloy steel or stainless steel bolt materials for high temperature or high pressure and other special purpose equipment" series products. Common grades in this standard: Gr.B7, B7M, etc.

2. Applicable to: high and medium pressure valves; marine, shipbuilding, chemical, fluid engineering; pressure vessels; petrochemical equipment and other high temperature and high pressure equipment, hydrogen sulfide corrosion resistance equipment.

3. Product dimensions can be selected in accordance with: GB897, GB898, GB899, GB900, GB901, GB/T9125 (full thread), HG/T20634 (full thread), HG/T20613 (full thread), JB/T4707 (equal length double head), SH/T3404, NB/T47027 (A, B, C type), DIN938, DIN939, IFI136, ASME B18.31.1M (metric), ASME B18.31.2 (inch), non-standard double head according to the drawing, etc. There are A type, B type, full thread.

4. Surface treatment: Xylan coating (1052, 1070/1424, 1425), etc.