城镇燃气管道动态直流杂散电流检测与防护措施研究

Research on Detection and Protection Measures of Dynamic DC Stray Current in Urban Gas Pipelines

为解决动态直流杂散电流引起的城镇燃气管道腐蚀问题,对直流杂散电流的腐蚀机理进行了分析,介绍了土壤表面电位梯度测量、管地电位正向偏移量测试等杂散电流检测方法。总结归纳出防止动态杂散电流腐蚀的措施有增加回路电阻、引入排流措施、加强阴极保护管理等。通过检验现场实际应用并跟踪监测,结果表明:引入牺牲阳极接地极并串接极性排流器的排流方法收到了良好效果,可以为同类管道的杂散电流防腐工程提供参考。

In order to solve the corrosion problem of urban gas metal pipeline caused by dynamic DC stray current,the corrosion mechanism of DC stray current was analyzed,and stray current detection methods such as soil surface potential gradient measurement and pipe-to-ground potential forward offset test were introduced.It is concluded that the measures to prevent dynamic stray current corrosion include increasing loop resistance,introducing drainage measures,and strengthening cathodic protection management.Through the field application and follow-up monitoring,the results show that the introduction of sacrificial anode grounding electrode and series connection of polar drain drainage method has achieved good results,which can provide a reference for stray current anti-corrosion projects of similar pipelines.