ASTM A592/A592M-04 covers the standard specification for high-strength quenched and tempered low-alloy steel forged fittings and parts used for pressure vessels. The steel shall be made by a melting process and shall be fully killed and fine grained. After forging and before reheating, the forgings shall be cooled to provide substantially complete transformation of austenite. Samples for mechanical test specimens shall be removed after the quenching and tempering heat treatment. The test specimens may be machined from a production forging or from special forged blocks suitably worked and heat treated with the production forgings. Such special blocks shall be obtained from an ingot, slab, or billet from the same heat as the forgings they represent and shall be reduced by forging in a manner similar to that for the products to be represented. The specimens shall undergo tension and Charpy V-notch impact tests.

1.1 This specification covers high-strength quenched and tempered low-alloy steel forged fittings and parts for pressure vessels. The maximum thickness of forgings under this specification shall be 1½ in. [38 mm] for Grade A, and 4 in. [100 mm] for Grades E and F.

Note 1—These grades are similar to corresponding grades in Specification A 517/A 517M.

1.2 Although no provision is made for supplementary requirements in this standard, the supplementary requirements in Specification A 788/A 788M may be considered by the purchaser.

1.3 Welding technique is of fundamental importance and it is presupposed that welding procedures will be in accordance with approved methods for the class of material used.

1.4 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 non-conformance with the standard.

1.5 Unless the order specifies the applicable “M” specification designation, the material shall be furnished to the inch-pound units.