The ASTM A537 specification is the Standard Specification for Pressure Vessel Plates, Heat-Treated, Carbon-Manganese-Silicon Steel used in the applications of fusion welded pressure vessels and structures. Typical applications are pressure vessels designed for moderate and lower-temperature service requiring excellent notch toughness as well as API 650 and API 620 storage tanks. Class 1 material is available as Normalized and Class 2 is available as Quenched & Tempered plates.
ASTM A537 Class 1
ASTM A537 Class 2