1.1 本规范涵盖标称重量为60磅/码（29.8千克/米）及以上的用于铁路轨道的碳钢三通钢轨，包括出口和工业应用。 1.2 补充要求S1和S2仅适用于买方在订单中规定的情况。 1.3 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 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 carbon steel tee rails of nominal weights of 60 lb/yd (29.8 kg/m) and over for use in railway track, including export and industrial applications. 1.2 Supplementary requirements S1 and S2 shall apply only when specified by the purchaser in the order. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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.