1.1 本试验方法描述了用于涂层管道接头、联轴器、不规则配件和修补区域的材料的比较防腐特性的测定。该试验方法适用于主要功能是在管道表面和周围土壤环境之间起屏障作用的材料。 1.2 所述测试方法使用泄漏电流、电容和损耗因子的测量来指示接头和修补材料的绝缘有效性的变化。 1.3 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.4 以国际单位制表示的三位有效小数的数值将被视为标准。括号中给出的值仅供参考。 1.5 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。 1.6 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。 ====意义和用途====== 4.1 如果允许与土壤环境接触，则其他涂层管道中接头、配件和受损区域的外露金属表面将受到腐蚀。设计用作保护层的接头和修补材料的性能将取决于以下因素，如材料与管道涂层和外露金属表面结合的能力、搭接接头处防潮密封的完整性以及接头材料的吸水特性。 4.2 通过涂层接头、补片或配件的大量泄漏电流的存在是该材料作为保护屏障的性能显著下降的可靠证据。以类似的方式，测量的接头电容和损耗因子的变化是有用的，因为它们与接头材料的吸水率有关。水渗透绝缘屏障会增加其电容，其过程可以通过使用合适的阻抗电桥来测量。

1.1 This test method describes determination of the comparative corrosion preventative characteristics of materials used for applications to joints, couplings, irregular fittings, and patched areas in coated pipelines. The test method is applicable to materials whose principal function is to act as barriers between the pipe surface and surrounding soil environment. 1.2 The test method described employs measurements of leakage current, capacitance, and dissipation factor to indicate changes in the insulating effectiveness of joint and patching materials. 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.4 The values stated in SI units to three significant decimals are to be regarded as the standard. The values given in parentheses are for information only. 1.5 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. 1.6 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. ====== Significance And Use ====== 4.1 The exposed metal surfaces at joints, fittings, and damaged areas in an otherwise coated pipeline will be subjected to corrosion if allowed to come in contact with the soil environment. The performance of joint and patching materials designed to function as protective coverings will depend upon such factors as the ability of the material to bond to both the pipe coating and exposed metal surfaces, the integrity of the moisture seal at lapped joints, and the water absorption characteristics of the joint material. 4.2 The existence of substantial leakage current through the coating joint, patch, or fitting is reliable evidence that the material has suffered a significant decrease in its performance as a protective barrier. In a similar manner, measured changes in joint capacitance and dissipation factor are useful because they are related to the water absorption rate of the joint material. Water permeating an insulating barrier increases its capacitance and its progress can be measured through the use of a suitable impedance bridge.