1. Scope
1.1 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.
1.2 STM A216 Steel 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 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 must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.
STM A216/A216M (WCA, WCB, WCC) (A105 is the forged version of this steel) – Typically referred to as a cast regular temp or reg temp steel. For each grade WC – stands for “wrought carbon” with the third letter indicating grade – the higher the grade the higher the tensile/yield strength.
This specification covers carbon steel castings for valves, fittings, flanges and other pressure-containing parts for high temperature service and the quality required for assembly with other castings or wrought steel parts by fusion welding. These grades are all “cast” grades meaning they are made through “casting” which is a manufacturing process where a liquid material is poured into a mold and allowed to harden.
Cast valves are typically less expensive than their forged counterparts for larger bore valves – though as a result of the casting process there is the potential for a porous cast (bad casting) which is why most high pressure valves are made with forged steel. NACE MR-0175 requires the use of double heat-treated cast steel castings.