Abstract
This specification covers a group of common requirements that are mandatory for steel castings produced by the investment casting process for pressure-containing parts. Master heats shall be made by the electric furnace process with or without separate refining such as argon-oxygen-decarburization (AOD), vacuum-oxygen degassing (VOD), vacuum-induction-melting (VIM). Ferritic and martensitic steel shall be cooled after pouring to provide complete transformation of austenite prior to heat treatment to enhance mechanical properties. Chemical, heat, and product analyses shall be performed and the chemical composition thus determined shall conform to the prescribed values in carbon, manganese, silicon, phosphorus, sulfur, nickel, chromium, molybdenum, vanadium, tungsten, copper, and aluminum. Tensile testing shall be done on the castings and shall meet the required yield and tensile strength, elongation, and reduction of area. Each casting shall also be tested after machining to hydrostatic shell pressure test and shall not show any leaks.
Scope
1.1 This specification covers a group of common requirements, that are mandatory for steel castings produced by the investment casting process for pressure-containing parts under each of the following ASTM Specifications:
| Title of Specification | ASTM Designation | |
| Steel Castings, Carbon, Suitable for Fusion Welding | A 216/A 216M | |
| for High-Temperature Service | ||
| Steel Castings, Martensitic Stainless and Alloy, for | A 217/A 217M | |
| Pressure-Containing Parts Suitable for High- | ||
| Temperature Service | ||
| Castings, Austenitic, Austenitic-Ferritic (Duplex), | A 351/A 351M | |
| for Pressure-Containing Parts | ||
| Steel Castings, Ferritic and Martensitic, for Pressure- | A 352/A 352M | |
| Containing Parts Suitable for Low-Temperature | ||
| Service | ||
| Steel Castings, Alloy, Specially Heat-Treated, for | A 389/A 389M | |
| Pressure-Containing Parts, Suitable for High- | ||
| Temperature Service | ||
| Steel Castings Suitable for Pressure Service | A 487/A 487M |
1.2 This specification also covers a group of supplementary requirements, which may be applied to the above specifications as indicated therein. These requirements are provided for use when additional testing or inspection is desired and apply only when specified individually by the purchaser in the order.
1.3 When investment casting is ordered, the requirements of this specification shall take precedence over the individual material specification requirements.
1.4 The values stated in either inch-pound or SI units are to be regarded separately as the standard. Within the text, the SI units are shown in brackets. The values in each system are not exact equivalent; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with this specification. Inch-pound units are applicable for material ordered to Specification A 985 and SI units for material ordered to Specification A 985M.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
