5% nickel SA645 GrA alloy steel plate for pressure vessel

Introduction to SA645 GrA alloy steel plate:
SA645 GrA steel plate is an alloy steel plate for ultra-low temperature pressure vessels, belonging to 5% nickel alloy steel plate with special heat treatment for pressure vessels. SA645 GrA steel plate has high strength, high toughness and excellent welding performance, and is often used to manufacture ultra-low temperature pressure vessels, pressure shells, heat resistant shells and other equipment.

Heat treatment process of SA645 GrA alloy steel plate:
1. Quenching hardening - steel plate shall be heated to 855-915℃ and kept at this temperature for at least 1h/in (2.4min/mm) wall thickness, but not less than 15min, and then water quenched to below 150℃.

2. Toughening treatment - reheat the steel plate to 690-760℃ and keep it at this temperature for at least 1h/in (2.4min/mm) wall thickness, but not less than 15min, and then water quenched to below 150℃.

3. Reverse annealing - reheat the above steel plates to 620-665℃ and keep them at this temperature for at least 1h/in (2.4min/mm) wall thickness, but not less than 15min, and then water quenched to below 150℃.

Impact temperature and executive standard of SA645 GrA steel plate:
Impact temperature: the impact temperature of SA645 GrA steel plate is - 140℃.

Executive standard: SA645 GrA steel plate is the American standard steel plate for vessels, and the ASME SA645/SA645M standard is implemented.