ASTM A844/A844M–93 (1999) pdf free.Standard Specification for Steel Plates, 9 % Nickel Alloy, for Pressure Vessels, Produced by the Direct-Quenching Process.
This specification covers 9% nickel-alloy steel plates produced by the direct-quenching process. The plates are intended primarily for use in welded pressure vessels.
3. General Requirements and Ordering Information
3.1 Material supplied to this material specification shall conform to Specification A 20/A 20M. These requirements outline the testing and retesting methods and procedures. permissible variations in dimensions, quality and repair of defects, marking. loading. etc.
3.2 Specification A 20/A 20M also establishes the rules for ordering infonnation that should be complied with when purchasing material to this specification.
3.3 Tn addition to the basic requirements of this specification. certain supplementary requirements are available when additional control. testing. or examination is required to meet end use requirements. These include:
3.3.1 Vacuum treatment.
3.3.2 Additional or special tension testing.
3.3.3 Additional or special impact testing. and
3.3.4 Nondestnictive examination.
3.4 The purchaser is referred to the listed supplementary requirements in this specification and to the detailed requirements in Specification A 20/A 20M.
3.5 If the requirements of this specification are in conflict with the requirements of Specification A 20/A 20M. the requirements of this specification shall prevail.
5. Chemical Composition
5. 1 The steel shall confonn to the chemical requirements shown in Table 1 unless otherwise modified in accordance with Supplementary Requirement S 17. Vacuum C arbon-Deoxidized Steel, in Specification A 20/A 20M.
6. Finish
6.1 The plates shall be descaled by the producer prior to shipment.
8. Marking
8.1 lii addition to the marking required in Specification A 20/A20M. each plate shall be legibly stamped or stenciled,depending upon the ordered thickness,9with the letters DQT except as otherwise specified in 8.1.1.
8. 1 . 1 When the optional heat treatment permitted in 4.2.2 is performed. the plates shall be marked with the letters DQTT instead of DQT.