This specification covers steel castings, martensitic stainless steel and alloys steel castings for valves, flanges, fittings, and other pressure-containing parts intended primarily for high-temperature and corrosive service. The grades of steels covered here are: Grade WC1, Grade WC4, Grade WC5, Grade WC6, Grade WC9, Grade WC11, Grade C5, Grade C12, Grade C12A, and Grade CA15. Heat treatment shall consist of normalizing and tempering for Grade C12A and tempering for all other grades. Heat treatments shall be performed after castings have been allowed to cool. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, molybdenum, chromium, nickel, vanadium, manganese, phosphorus, sulfur, silicon, columbium, nitrogen, aluminum, copper, titanium, tungsten, and zirconium. The surface of the casting shall be examined visually and shall be free of adhering sand, scale, cracks and hot tears. Steels shall undergo tension test, and shall conform to the following mechanical requirements: tensile strength, yield strength, elongation, and reduction of area.