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

3. Specifications: Metric M20-M160, Metric 1"-6"

4. 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.

5. Surface treatment: natural color, phosphating, blackening, zinc plating (Zn), Dacrotized, Xylan coating.