交流干扰——埋地管道完整性的新威胁及其危险性的分类标准

AC Interference - New Threat on Integrity of Buried Pipeline and Classification of Its Dangerous Nature

对埋地钢质管道由于与高压交流输电线路、高压交流电力机车等的平行、交叉和靠近铺设，所带来的交流腐蚀的分析，说明对在建或运行中的埋地管道，必须重视来自高压交流输电线路的交流干扰以及来自高压交流电气化轨道的干扰的检测、排查、与评估。本文介绍了国际上对交流干扰危险性新的分类标准，以及在交流干扰存在下通过接地排流、或隔直流排流等手段来减缓交流干扰的电压后，又如何通过基于直流电流密度与交流电流密度指标来评价管道的阴极保护的有效性，这也是近年来国外研究与探讨的主要课题。通过本文介绍，希望加强国内关于交流干扰的检测与研究的重视，并进一步制定与国际同步的标准规范，以指导行业内的设计、检测行为，保证埋地油气管道的安全运行。通过本文介绍，希望促进国内关于交流干扰的检测与研究的重视，并进一步制定与国际同步的标准规范，以指导行业内的设计、检测行为，保证埋地油气管道的安全运行。

AC - induced corrosion will be occurred if the buried steel pipelines are laid near by or parallel to or crossing the high vohage AC transmission line and/or high voltage AC electric locomotive. For the buried pipelines being operated or constructed, it must lay stress on the detection, survey and as- sessment of AC interference from the high voltage AC transmission line and/or high voltage AC electric locomotive. This paper introduces the updated classification of AC interference dangerous nature. It also introduces the hot topics how to mitigate AC interference by earthing drainage or isolating DC drainage under AC interference and how to evaluate the cathodic protection effectiveness by DC current density and AC current density. The author hopes the study on the AC interference will be strengthened at home and a national standard will be prepared to keep in line with the international standard and it could become the guide in design and detection to ensure a safety operation of the buried oil and gas pipelines.