城市小区低压燃气管网腐蚀泄漏事故频发,补加阴极保护是减缓腐蚀的重要措施,但小区地下金属结构物种类较多,低压燃气管道无法与建筑物接地、楼房钢筋等进行有效绝缘,电流开放分布的特征成为阴极保护有效实施的技术难题。通过现场馈电试验,分析了深井阳极地床、远阳极地床、近阳极地床等3种地床形式下电流的分布规律及保护效果,结果显示近阳极地床能够有效减少接地的干扰,是适用于低压燃气管网的阳极地床形式。同时,利用数值模拟计算,得到了浅埋分布式辅助阳极地床分布方案。

There are frequent leakage accidents caused by corrosion on the low-voltage gas pipeline network in urban communities, supplementary catodic protection is an important mesure to slow down corrosion. But there are many types of underground metal structures in the communities. Low-voltage gas pipelines cannot be effectively insulated from building grounding, building steel bars, etc. The characteristic of open current distribution becomes a difficult problem for effective implementation of cathodic protection technology. Through the field feeding test, the current distribution law and protection effect in three ground bed forms, including deep well anode ground bed, far anode ground bed and near anode ground bed, were analyzed. The results show that the near anode ground bed could effectively reduce grounding interference, it is a anode ground bed form suitable for low-voltage gas pipeline network. At the same time, using numerical simulation calculation, the distribution scheme shallow buried distributed auxiliary anode ground bed was obtained.