某输气管道受地铁杂散电流干扰影响,阴极保护电位波动大,且长时间正于-850 mV(相对于CSE),阴极保护系统受干扰严重,管道受阴极保护效果未知。为了解管道真实阴极保护状况,对沿线管道土壤电阻率进行测试,对管道通断电电位进行了24 h监测,确定了管道最小阴极保护电位,并评估了管道阴极保护状况。基于管道干扰风险分析结果,调整了阴极保护站输出参数,并开展了现场馈电试验。通过连续的馈电测试,获得了较优的干扰防护措施。

A gas transmission pipeline was affected by the subway interference. The pipeline cathodic protection potential fluctuated greatly and was positive than -850 mV(compared to CSE) for a long time. As a result, the cathodic protection system was seriously interfered, and the effect of cathodic protection on the pipeline was unknown. In order to know the real cathodic protection status of the pipeline, the soil resistivity was tested, and the pipeline potential were monitored for 24 hours, so as to determine the minimum cathodic protection potential value and evaluate the cathodic protection status of the pipeline. Based on the corrosion risk analysis results, the cathodic protection station running parameters were adjusted and continuous feeding tests were carried out. Through continuous field test, an optimized interference protection method was obtained.