管道保护电位测试及腐蚀点检测  

Pipeline protection potential test and corrosion point detection

作　　者：郑晓伟 ZHENG Xiao-wei(Sinopec Jiangsu Oil Construction Engineering Co.,Ltd.North China Regional Project Department,Hanjiang 225100,China)

机构地区：[1]中石化江苏油建工程有限公司华北区域项目部,江苏邗江225100

出　　处：《全面腐蚀控制》2024年第11期204-207,共4页Total Corrosion Control

摘　　要：管道外涂覆层腐蚀是管道运行维护中常见的问题,尤其是沿海水网地带普遍为盐性土且地下水矿化度高;当防腐层搭接面渗水、点面锈蚀及管壁减薄等缺陷形式破坏后,易导致腐蚀点处保护电位不达标,继而加快管道腐蚀,造成钢管厚度变薄,锈蚀爆裂等,发生泄漏事故造成较大损失。因此检测管道的外涂层质量评估风险,找出并修复漏点,保障管道的安全运行工作变得尤为重要。缺陷查找一般采用(PCM)多频管中电流衰减法的原理检测,利用英国雷迪公司的PCM-TX设备查找外壁上的漏点缺陷;目前埋地管道防腐蚀措施主要为3PE防腐层及强制电流阴极保护,测量管道保护电位、电流衰减率等能对防腐层质量评估检测。Pipeline coating corrosion is a common problem in pipeline operation and maintenance,especially in coastal water network areas where saline soil and high groundwater mineralization are common.When the anti-corrosion layer is damaged by defects such as water seepage on the overlap surface,spot corrosion,and thinning of the pipe wall,it is easy to cause the protection potential at the corrosion point to fail to meet the standard,which in turn accelerates pipeline corrosion,causing the steel pipe thickness to become thinner,rust and crack,etc.,and leakage accidents cause great losses.Therefore,it is particularly important to detect the quality of the pipelines outer coating,assess the risk,find and repair leaks,and ensure the safe operation of the pipeline.Defect detection generally adopts the principle of(PCM)multi-frequency tube current decay method,and uses the PCM-TX equipment of British Radiodetection Company to find the leakage point defects on the outer wall;At present,the main anti-corrosion measures for buried pipelines are 3PE anti-corrosion layer and forced current cathodic protection.Measuring pipeline protection potential,current attenuation rate,etc.can evaluate and detect the quality of the anti-corrosion layer.

关 键 词：电位测试 ACVG A字架 干扰源 

分 类 号：TE832[石油与天然气工程—油气储运工程]