1.1 本规程包括通过tup（落锤）测定热塑性塑料管道和配件在规定冲击条件下的抗冲击性。tup上使用了三个可互换的敲击头，在几何结构上有所不同。描述了两个样本夹持器。 注1: 附录X1 显示了确定冲击强度的程序。 1.2 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。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、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（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。 ====意义和用途====== 4.1 热塑性塑料管道和配件的抗冲击性与服务的适用性和加工质量有关。抗冲击性还可以提供材料在搬运和安装过程中抗破坏性的相对测量值，对于非埋地应用，还可以提供在役抗破坏性的相对测量值。看见 附录X5 有关选择测试组合的指南。 4.2 通过使用本规程获得的结果可通过三种方式使用: 4.2.1 作为在产品标准中建立冲击试验要求的基础， 4.2.2 测量材料或加工变化的影响，以及 4.2.3 测量环境的影响。

1.1 This practice covers the determination of the impact resistance of thermoplastic pipe and fittings under specified conditions of impact by means of a tup (falling weight). Three interchangeable striking noses are used on the tup, differing in geometrical configuration. Two specimen holders are described. Note 1: Appendix X1 shows the procedure to determine impact strength. 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 impact resistance of thermoplastic pipe and fittings relates to suitability for service and to quality of processing. Impact resistance may also provide a relative measure of a material's resistance to breakage during handling and installation and, for non-buried applications, to in-service breakage. See Appendix X5 for guidelines for selecting testing combinations. 4.2 Results obtained by use of this practice can be used in three ways: 4.2.1 As the basis for establishing impact test requirements in product standards, 4.2.2 To measure the effect of changes in materials or processing, and 4.2.3 To measure the effect of the environment.