1.1 本规范涵盖厚度为6英寸的结构质量淬火和回火合金钢板。[150 mm]及以下，主要用于焊接结构和其他非焊接结构。 注1: 并非所有等级的最大厚度都为6英寸。[150毫米]。看见 表1 适用于每个等级的厚度。 1.2 如果要焊接钢材，则应采用适合钢材等级和预期用途或服务的焊接工艺。见规范附录X3 A6/A6M系列 有关焊接性的信息。 1.3 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，SI单位显示在括号中。每个系统中规定的值可能不完全相等；因此，每个系统应独立于其他系统使用。结合两个系统的值可能会导致不符合标准。 1.4 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 covers quenched and tempered alloy steel plates of structural quality in thicknesses of 6 in. [150 mm] and under intended primarily for use in welded structures and other non-welded structures. Note 1: All grades are not available in a maximum thickness of 6 in. [150 mm]. See Table 1 for thicknesses available in each grade. 1.2 If the steel is to be welded, it is presupposed that a welding procedure suitable for the grade of steel and intended use or service will be utilized. See Appendix X3 of Specification A6/A6M for information on weldability. 1.3 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 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. 1.4 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.