This specification covers steel castings for valves, flanges, fittings, and other pressure-containing parts intended primarily for low-temperature service. Several grades of ferritic steels and one grade of martensitic steel are covered. All castings shall receive a heat treatment proper to their design and chemical composition. It should be recognized that liquid quenching of the ferritic grades is normally required to meet the mechanical properties of heavier sections. The steel shall conform to the requirements as to chemical composition specified. Tensile test and impact test shall be made to conform to the requirements specified.