1.1本规范涵盖碳钢梁轨道 根据类型或类型和重量，以及定义如下和表1中的化学成分，分为三类: 1.1.1除非买方另有规定，否则主梁护栏应为A级。 1.1.2重量低于135磅/码（67.1千克/米）的平梁和槽梁轨道应由买方指定为A级或B级。 1.1.3除非另有规定，否则重量为135磅/码及以上的平梁和槽梁轨道应为C级。 1.2数值以英寸为单位- 磅单位应视为标准。括号中给出的值仅供参考。

1.1 This specification covers carbon steel girder rails of three classes based on type or type and weight, and chemistry defined as follows and in Table 1: 1.1.1 Unless otherwise specified by the purchaser, girder-guard rails shall be Class A. 1.1.2 Plain and grooved-girder rails under 135 lb/yd (67.1 kg/m) in weight shall be specified by the purchaser as either Class A or Class B. 1.1.3 Plain and grooved-girder rails of 135 lb/yd in weight and heavier shall be Class C, unless otherwise specified. 1.2 The values states in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.