ASTM A 540/A540M : 2026

1.1ÂThis specification covers regular and special-quality alloy steel bolting materials and bolting components that may be used for nuclear and other special applications. See Specification A962/A962M for the definition of bolting.

1.2ÂThe following referenced common requirements are indispensable for application of this specification: Specification A962/A962M.

1.3ÂSupplementary requirements of an optional nature are provided for use at the option of the purchaser. These supplementary requirements only apply when specified individually by the purchaser in the purchase order or contract.

1.4ÂThis specification is expressed in both inch-pound units and in SI units; however, unless the purchase order or contract specifies the applicable “M” specification designation (SI units), inch-pound units shall apply.

1.5ÂThe values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. 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 non-conformance with the standard.

1.6ÂThis 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.