重庆某输气管道地铁杂散电流干扰检测评价与防护案例研究

重庆某输气管道沿线与多条地铁、轻轨交叉并行，管道阴极保护系统受干扰严重。为了认识管道沿线阴极保护水平和真实干扰情况，对其阴极保护参数进行了现场测试。根据测试结果，分析获得了管道沿线干扰大小的分布情况。基于分析结果，利用智能抗干扰恒电位仪开展现场馈电试验。结果表明，在合理分布辅助阳极地床的情况下，利用强制电流阴极保护和牺牲阳极相结合的方法可以将管道的干扰水平控制在可接受范围内。该研究成果可为油气管道动态直流干扰的分析和防护设计提供参考。

Case Study of DC Transit Stray Current Interference with Buried Metallic Pipeline: Field Test,Risk Evaluation and Mitigation

In this case, a gas pipeline was buried close to several metro or light rail transit systems in Chongqing, China. As a result, the cathodic protection system of the pipeline ran out of work. Cathodic protection parameters, as well as the corrosion potential of the stray current disturbed pipeline were measured in order to get the true evidence of stray current interference. Results showed that the present cathodic protection system was not satisfied to protect pipeline from DC transit stray current interference. Effect of DC transit stray current on corrosion potential along the stray current disturbed pipeline was analyzed. Based on the results, feeding trials test was conducted for a system under impressed current cathodic protection. It follows that the DC transit stray current interference could be controlled by the combined utilization of impressed current cathodic protection and sacrificial anode in the case that the auxiliary anode bed was designed and constructed reasonably.