1.1 本规范适用于桥梁和建筑物的焊接、铆接或螺栓连接结构，以及需要高强度和增强耐大气腐蚀性的一般结构用冷成型焊接和无缝高强度、低合金圆形、方形、矩形或特殊管状型材( 注1 ). 这种钢在大多数环境中的耐大气腐蚀性大大优于添加或不添加铜的碳钢( 注释2 ). 当适当暴露在大气中时，这种钢可以裸（未涂漆）用于许多应用。 当该钢材用于焊接结构时，焊接程序应适用于钢材和预期用途。 1.2 这种管子的焊接尺寸最大为88英寸。[2235毫米]，最大壁厚1英寸。[25.4 mm]，无缝，最大周长32英寸。[813 mm]，最大壁厚0.500 in。[12.7毫米]。可提供其他尺寸的管道，前提是此类管道符合本规范的所有其他要求。 注1: 按照本规范制造的产品可能不适用于低温缺口韧性性能可能很重要的应用，例如焊接结构中的动态加载元件，除非订购时进行韧性测试。 见补充要求。 注2: 有关估算低合金钢耐大气腐蚀性的方法，请参阅指南 G101 或实际数据。 1.3 以国际单位制或英寸-磅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可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并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 cold-formed welded and seamless high-strength, low-alloy round, square, rectangular, or special tubular shapes for welded, riveted, or bolted construction of bridges and buildings and for general structural purposes where high strength and enhanced atmospheric corrosion resistance are required ( Note 1 ). The atmospheric corrosion resistance of this steel in most environments is substantially better than carbon steel with or without copper addition ( Note 2 ). When properly exposed to the atmosphere, this steel can be used bare (unpainted) for many applications. When this steel is used in welded construction, the welding procedure shall be suitable for the steel and the intended service. 1.2 This tubing is produced in welded sizes with a maximum periphery of 88 in. [2235 mm] and a maximum wall of 1 in. [25.4 mm], and in seamless with a maximum periphery of 32 in. [813 mm] and a maximum wall of 0.500 in. [12.7 mm]. Tubing having other dimensions may be furnished provided such tubing complies with all other requirements of this specification. Note 1: Products manufactured to this specification may not be suitable for those applications where low temperature notch toughness properties may be important, such as dynamically loaded elements in welded structures, unless ordered with toughness tests. See the Supplementary Requirements. Note 2: For methods of estimating the atmospheric corrosion resistance of low alloy steels, see Guide G101 or actual data. 1.3 The values stated in either SI units or inch-pound 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.