意义及用途
5.1 方法A — Method A describes a rapid and safe method for determining whether there are pinholes, 空隙, or metal particles protruding from the coating. 然而, this method does not detect any thin spots in the coating. This method will determine if there are any serious defects in the film pipe coating.

5.2 方法B — Method B describes a method for determining whether there are pinholes, 空隙, or metal particles protruding from the coating and thin spots in the pipe coating. The method can be used to verify minimum coating thickness as well as voids in quality control applications.

ASTM G62-2022 管道涂层泄漏点检测的标准测试方法

范围
1.1 These test methods cover equipment and procedures for detecting leaks in pipe-type coatings.

1.2 Method A is designed to detect defects such as holes and voids in thin film coatings of a thickness of 0.025 到 0.254 毫米 (1 到 10 米尔) using ordinary tap water and an applied voltage of less than 100 V DC. If the wetting agent is used with water, it is effective against films up to 0.508 毫米 (20 米尔) thick. 然而, it should be noted that this method does not detect thin spots in the coating. Due to the relatively low voltage, this can be considered non-destructive testing.

1.3 Method B is used to detect defects such as pinholes and voids in pipeline coatings; But because of the higher voltage applied, it can also be used to detect thin spots in coatings. The method can be used for pipe coatings of any thickness and uses 900 到 20 000 V DC voltage. 2 This method is considered destructive because the high pressure involved usually destroys the coating at thin points.

1.4 The value of the International System of Units with three significant decimals shall prevail. 括号内的数值仅供参考.

1.5 本标准并非旨在解决所有问题, 如果有的话, 与其使用相关的安全问题. 本标准的使用者有责任建立适当的安全机制, 健康和环境实践，并在使用前确定监管限制的适用性.

1.6 本国际标准基于《国际标准决定》中确立的国际公认的标准化原则, Guidelines and Recommended Principles issued by the WTO Committee on Technical Barriers to Trade (技术性贸易壁垒).