1.1 本规范 2. 涵盖NPS 2至NPS 30[DN 50至DN 750]中的两个等级的电阻焊接钢管，标称（平均）壁厚高达0.500英寸。[12.70 mm]，包括在内，标称尺寸NPS 3. / 4. 至NPS 5[DN 20至DN 125]，包括标称（平均）壁厚0.083英寸。[2.11毫米]至0.134英寸。[3.40 mm]，取决于尺寸。具有其他尺寸的管道( 注1 )可提供符合本规范所有其他要求的管道。管道用于输送气体、蒸汽、水或其他液体；仅A级适用于翻边和弯曲( 注释2 ). 管道的适用性在某种程度上取决于其尺寸、性能和使用条件，因此应在订单中说明管道的预期用途。根据制造商的选择，可提供非膨胀或冷膨胀管道。当管道冷膨胀时，膨胀量不得超过1.5 % 外径管道尺寸。 注1: ASME B36.10M中包含标准化管道尺寸的综合列表。 注2: 本规定并非旨在禁止B级管道的冷弯。 1.2 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。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。 1.3 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 2 covers two grades of electric-resistance-welded steel pipe in NPS 2 to NPS 30 [DN 50 to DN 750] inclusive, with nominal (average) wall thickness up to 0.500 in. [12.70 mm], inclusive, and in nominal sizes NPS 3 / 4 to NPS 5 [DN 20 to DN 125] inclusive with nominal (average) wall thickness 0.083 in. [2.11 mm] to 0.134 in. [3.40 mm], depending on size. Pipe having other dimensions ( Note 1 ) may be furnished provided such pipe complies with all other requirements of this specification. The pipe is intended for conveying gas, vapor, water or other liquid; only Grade A is adapted for flanging and bending ( Note 2 ). The suitability of pipe for various purposes is somewhat dependent upon its dimensions, properties, and conditions of service, so that the purpose for which the pipe is intended should be stated in the order. The pipe may be furnished either nonexpanded or cold expanded at the option of the manufacturer. When pipe is cold expanded, the amount of expansion shall not exceed 1.5 % of the outside diameter pipe size. Note 1: A comprehensive listing of standardized pipe dimensions is contained in ASME B36.10M. Note 2: This provision is not intended to prohibit the cold bending of Grade B pipe. 1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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. 1.3 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.