1.1 本规范涵盖热锻和冷加工淬火和回火合金钢棒。 1.2 热锻棒材有BB、BC和BD三种强度等级，冷精加工棒材有BB和BC两种强度等级。这些条在中指定的条件下可用 5.4 受所示尺寸限制。 1.3 以SI单位或英寸-磅单位表示的值应单独视为标准值。每个系统中陈述的值不一定完全等同；因此，为确保符合标准，每个系统应独立使用，两个系统的数值不得合并使用。 1.4 本国际标准是根据世界贸易组织技术壁垒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贸易委员会。

1.1 This specification covers hot-wrought and cold-finished quenched and tempered alloy steel bars. 1.2 Hot-wrought bars are available in three strength level classes designated BB, BC, and BD, and cold-finished bars in two strength level classes designated BB and BC. The bars are available in the conditions specified in 5.4 subject to the size limitations shown. 1.3 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. 1.4 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.