基于DM的长输管道外防腐层检测技术

Research on the Detection Technology of External Corrosion Protection Coating Based on DM

通过比较当前长输管道外防腐层检测各种技术,得出DM(多频管中电流法)的优越性,同时介绍了DM检测技术原理,详细分析了DM在长输管道外防腐层检测中破损点严重程度评定和定位技术,及在管道整体外防腐层等级综合评价中的应用,在实际检验中得出破损点性质判定规律及如何根据信号图来判断缺陷方法,该文得出一些规律有利于提高DM在长输管道外防腐层检测中的缺陷检测率和准确率。

By comparing the various detection technologies of the external corrosion protection coating of the long distance pipeline, the superiority of DM（multi frequency tube current method） is obtained. At the same time, the principle of DM is introduced, the severity assessment and location technology of damage point of DM in the detection of the long distance pipeline coating are analyzed in detail, and application of the comprehensive evaluation of the whole outer coating of the pipeline.In the actual test, the characteristics of the damage point and how to judge the defect method according to the signal map are obtained. This paper draws some rules to improve the detection rate and accuracy of DM in the detection of the long pipeline coating.