1. ASTM A320/A320M-2018 "Standard Specification for Alloy Steel and Stainless Steel Bolting Materials for Low Temperature" series of external threaded fastener products: Common grades in this standard: Gr.L7, L7M, L43, etc.

2. Applicable to: industrial high and medium pressure valves; marine, shipbuilding, chemical, fluid engineering; pressure vessels, pressure pipelines; petrochemical equipment; new energy, environmental protection equipment and other low temperature and high pressure environments.

3. The stud dimensions can be selected in accordance with: GB/T897, GB/T898, GB/T899, GB/T900, GB/T901, 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: natural color, phosphating, blackening, galvanized (Zn), Dacrotized, Xylan coating.