【国外标准】 Standard Specification for Steel Castings, Carbon, Suitable for Fusion Welding, for High-Temperature Service

This specification covers carbon steel castings for valves, flanges, fittings, or other pressure-containing parts for high-temperature service and of quality suitable for assembly with other castings or wrought-steel parts by fusion welding. Covered here are three grades of carbon steel (Grades WCA, WCB, and WCC), the selection of which shall depend on the design and service conditions, mechanical properties, and the high temperature characteristics. Castings shall be heat treated and furnished, as appropriate to their design and chemical composition, in the annealed, or normalized, or normalized and tempered conditions after they have been allowed to cool below the transformation range. Furnace temperatures for heat treating shall be effectively controlled by pyrometer. Steel castings shall adhere to chemical composition and tensile property requirements, which include tensile strength, yield strength, elongation, and reduction of area. The surface of castings shall be free of adhering elements such as sand, cracks, hot tears, and other discontinuities, and as such be repair welded when judged appropriate.1.1 This specification2 covers carbon steel castings for valves, flanges, fittings, or other pressure-containing parts for high-temperature service and of quality suitable for assembly with other castings or wrought steel parts by fusion welding.1.2 Three grades, WCA, WCB, and WCC, are covered in this specification. Selection will depend upon design and service conditions, mechanical properties, and the high-temperature characteristics.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.