1.1 本规范 2. 涵盖压力容器用高强度调质低合金钢锻件。本规范下锻件的最大厚度应为1 1. / 2. A级为38毫米，E和F级为100毫米。 注1: 这些等级与规范中的相应等级相似 517/517m . 1.2 虽然本标准中没有规定补充要求，但规范中的补充要求 A788/A788M 买方可以考虑。 1.3 焊接技术至关重要，前提是焊接程序将符合所用材料类别的批准方法。 1.4 以国际单位制或英寸表示的值- 磅单位应单独视为标准单位。每个系统中所述的值不一定是完全等效的；因此，为确保符合标准，每个系统应独立使用，两个系统的值不得组合。 1.5 除非订单规定了适用的“M”规格名称，否则材料应按英寸-磅单位提供。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。

1.1 This specification 2 covers high-strength quenched and tempered low-alloy steel forged parts for pressure vessels. The maximum thickness of forgings under this specification shall be 1 1 / 2 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 A517/A517M . 1.2 Although no provision is made for supplementary requirements in this standard, the supplementary requirements in Specification A788/A788M 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 are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. 1.5 Unless the order specifies the applicable “M” specification designation, the material shall be furnished to the inch-pound units. 1.6 This 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.