【国外标准】 Standard Test Method for Evaluating Pipeline Coating Patch Materials

3.1 Holidays in pipeline coatings may be repaired by circumferential wrapping with a suitable pipe wrap tape. However, this technique is not always practicable and patching may be required. The effectiveness of a patch material depends upon its adhesion to the original pipeline coating to effect sealing.3.2 The results of this accelerated test have been found to yield comparative data useful for the selection of patching materials. The user is cautioned against the use of this method for absolute material properties characterization.3.3 This procedure provides an accelerated method by exposing the patch to a severe radius of curvature on small-diameter pipe. The specimen is also exposed to a stress voltage in the presence of a highly conductive electrolyte.1.1 This test method provides an accelerated means of determining the relative sealing abilities of pipeline patching materials that are used to seal holidays in pipeline coatings on steel pipe. This test method is intended for utilization of specimens of pipeline coatings on small-diameter pipe, for representing coatings used for buried or submerged service, and where the purpose of the coating is to provide an electrical barrier between the steel pipe and its environment.1.2 This test method is not intended for evaluating patch materials that are overlapped upon themselves.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 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.1.5 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.