1.1 本规范 2. 涵盖主要用于制造焊接压力容器的铬钼钒合金钢板。 1.2 根据本规范提供的板材需要正火和回火。规格 A542/A542M 包括淬火和回火条件下材料的覆盖范围。 1.3 根据本规范提供的板材的最大厚度仅受满足规定性能要求的成分能力的限制。 1.4 该材料适用于熔焊。焊接技术至关重要，前提是焊接程序将符合批准的方法。 1.5 本规范以英寸-磅单位和国际单位制表示。但是，除非订单规定了适用的“M”规格名称（国际单位制），否则材料应以英寸-磅为单位提供。 1.6 以英寸-磅单位或国际单位表示的数值应单独视为标准值。在文本中，国际单位显示在括号中。每个系统中规定的值必须独立于其他系统使用。合并两个系统的值可能会导致不符合规范。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。

1.1 This specification 2 covers chromium-molybdenum-vanadium alloy steel plates intended primarily for the fabrication of welded pressure vessels. 1.2 The plates furnished under this specification are required to be normalized-and-tempered. Specification A542/A542M includes coverage of the material in the quenched-and-tempered condition. 1.3 The maximum thickness of plates furnished to this specification is limited only by the capacity of the composition to meet the specified property requirements. 1.4 The material is intended to be suitable for fusion welding. Welding technique is of fundamental importance and it is presupposed that welding procedures will be in accordance with approved methods. 1.5 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units. 1.6 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 must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification. 1.7 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.