Active Standard ASTM A181 / A181M | Developed by Subcommittee: A01.22
Book of Standards Volume: 01.01
Historical (view previous versions of standard)
This specification covers the carbon steel forgings used for general-purpose piping. Two classes of material are covered, Classes 60 and 70, and classified according to their mechanical properties. Except for flanges of all types, up to and including NPS 4 may be machined from hot-rolled or forged bar. Elbows, return bends, tees, and header tees shall not be machined directly from bar stock. Forgings shall be protected against sudden or too rapid cooling from the rolling or forging while passing through critical range. Heat treatment is neither required nor prohibited, but when applied, it shall consist of tempering, annealing, normalizing, or normalizing and tempering. Heat analysis shall be made to determine the percentage of the following elements: carbon, manganese, phosphorus, silicon, and sulfur. The mechanical properties of the material shall conform to the required tensile properties: tensile strength, yield strength, elongation, and reduction of area.
This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
1.1 This specification2 covers nonstandard as-forged fittings, valve components, and parts for general service. Forgings made to this specification are limited to a maximum weight of 10 000 lb [4540 kg]. Larger forgings may be ordered to Specification A266/A266M.
1.2 Two classes of material are covered, designated as Classes 60 and 70, respectively, and are classified in accordance with their mechanical properties as specified in 6.1.
1.3 This specification is expressed in both inch-pound units and SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units.
1.4 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.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
A266/A266M Specification for Carbon Steel Forgings for Pressure Vessel Components
A788/A788M Specification for Steel Forgings, General Requirements
A961/A961M Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications
ICS Number Code 77.140.85 (Iron and steel forgings)
UNSPSC Code 31132100(Steel forgings)