多频管中电流法在管道外防腐层检测评价中的应用研究

Study on the application of PCM method in anti-corrosion layer testing parameters rating.

输油管道外腐蚀是引发管道失效的最主要因素之一。PCM通过计算管道防腐层绝缘电阻来判断管道外防腐层的状态,近年来在管道检测中得到较为广泛的应用。但实际使用后发现,对于丘陵山地的埋地输油气管道,其软件评价结果与实际外腐蚀情况有一定差距。通过理论研究发现,造成防腐层的评价结果与实际状态不符的主要原因是:管道分布电容、管道分布电感,尤其是管道分布电感是影响防腐层绝缘电阻评价的关键参数。该研究修正了多频管中电流法评价软件给出的管道分布电感推荐值,并采用现场开挖的方式进行验证,使PCM检测的评价结果更符合山地实际。

Buried steel pipeline corrosion is one of the most important factors in the failure of the pipeline. Through the pipeline coating calculation to determine pipe insulation resistance, PCM has been widely used in recent years in the pipeline inspection. However, to the buried gas pipelines under hills and mountains, there is difference between the evaluation results and the actual state. Study finds that the coating of the evaluation results and the actual status is not the main reason. Distribution channels and capacitors, inductors in the distribution pipeline GDWFF processing software in the preservation influence the results greatly, in particular the distribution channel, which is the key parameters to influence Coating insulation resistance evaluation. This article modifies the recommended pipeline distribution inductance L value suggested by PCM software evaluation. The value is verified by field excavation, so the PCM test results are more practical in the mountain areas.