This specification covers standard requirements for high-strength quenched and tempered alloy steel plates intended for use in fusion welded boilers and other pressure vessels. The steel shall be killed and shall conform to the fine austenitic grain size requirement. Heat and product analyses shall be conducted wherein the material shall conform to the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, boron, vanadium, titanium, zirconium, copper, and columbium. Tensile properties of the steel plate shall meet the specified values for tensile strength, yield strength, and elongation. The material shall undergo mechanical tests such as tension test and transverse Charpy V-notch impact test.

1.1 This specification covers high-strength quenched and tempered alloy steel plates intended for use in fusion welded boilers and other pressure vessels.

1.2 This specification includes a number of grades as manufactured by different producers, but all having the same mechanical properties and general characteristics.

1.3 The maximum thickness of plates furnished under this specification shall be as follows:

1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system is to be used independently of the other without combining values in any way.