输油管道外防腐层破损缺陷识别及开挖验证

Defect Identification and Excavation Verification for External Anticorrosive Coating of Oil Pipeline

埋地钢质管道在石油化工、天然气等行业中发挥着重要的作用,由于埋地管道施工及运行环境复杂,外防腐层破损时有发生,会导致管道的腐蚀。采用电位梯度法对原油输送管道上360m长的管段外防腐层进行了检测,应用ESTEC分析软件计算出防腐层电阻率,分析识别破损缺陷并按相关标准评价防腐层等级。最后利用开挖后直接检查的方法验证了外防腐层检测技术,结果表明,直接检查出的缺陷与防腐层检测的缺陷发现一致。

Buried steel pipeline plays a significant role in petrochemical,natural gas and other industries.Due to complicated environment of construction and operation,damage on external anticorrosion coating happens from time to time,thus accelerates corrosion.Electric potential gradient was adopted to detect 360 m pipeline coating.ESTEC software was applied to calculate insulation resistivity of the coating.Defects were identified and anticorrosion grade was evaluated according to relevant standards.Finally,detection technology on external anticorrosive coating was verified by excavation verification.It is proved that the detection signal of defect is consistent with that of anticorrosion coating.