1.1 本试验方法涵盖了测定矩形和方形铜及铜合金管扭曲角度的要求。 1.2 以英寸-磅单位表示的值应被视为标准值。括号中给出的值是对国际单位制的数学转换，仅供参考，不被视为标准值。 1.3 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 4.1 本试验方法涵盖的矩形或方形铜合金管可用于扭转控制对最终组装中的正确装配很重要的应用，并最大限度地减少返工以使管符合要求。人们认识到，在测量过程中，扭曲量（单位为度/长度增量）可能会因产品的重量及其长度而变化。 4.2 本试验方法提供了一种测量方形和矩形铜及铜合金管扭曲度的程序，作为测量直线度偏差的方法。 4.3 该测试方法允许买方和供应商或制造商使用标准技术检查方形和矩形铜及铜合金管，该技术在交付的管中提供可接受的扭曲。

1.1 This test method covers the requirements for the determination of the angle of twist in rectangular and square copper and copper alloy tube. 1.2 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. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 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. ====== Significance And Use ====== 4.1 The rectangular or square copper alloy tube covered by this test method may be used in applications in which control of twist is important to proper fit in final assembly and to minimize rework to bring the tube into compliance. It is recognized that the amount of twist, in degrees per increment of length, can change as a result of the weight of the product and its length during measurement. 4.2 This test method provides a procedure for measuring the twist in square and rectangular copper and copper alloy tubes as a measure of the deviation from straightness. 4.3 This test method allows the purchaser and supplier or manufacturer to inspect square and rectangular copper and copper alloy tube with a standard technique that provides acceptable twist in delivered tubes.