1.1 本规范描述了适用于地下排水和污水管道系统的柔性过渡接头（以下简称“接头”）的装置或组件的特性。 1.2 符合本标准要求的挠性过渡管接头适用于连接平端管或管件。待连接的管道应具有相似或不同的材料、尺寸或两者。 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 此处引用的ASTM标准应视为强制性标准。 1.5 对本标准具有管辖权的委员会不知道本标准所涵盖材料的另一个可比标准。 1.6 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 describes the properties of devices or assemblies suitable for use as flexible transition couplings, hereinafter referred to as “couplings,” for underground drainage and sewer piping systems. 1.2 Flexible transition couplings that conform to the requirements of this standard are suitable for joining plain-end pipe or fittings. The pipe to be joined shall be of similar or dissimilar materials, size, or both. 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 The ASTM standards referenced herein shall be considered mandatory. 1.5 The committee with jurisdiction over this standard is not aware of another comparable standard for materials covered in this standard. 1.6 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.