青岛地铁13号线对某管道直流干扰及治理研究

Research on interference to a pipeline in Qingdao caused by stray direct currentfrom metro line 13 and the corresponding mitigation measures

针对青岛地铁13号线对某管道的直流杂散电流干扰影响,为明确地铁直流干扰的影响范围、程度以及腐蚀特征,同时验证相关缓解治理措施的有效性,在评估管道阴保系统运行有效性的基础上,开展直流杂散电流干扰影响的现场检测评价、现场腐蚀试片、临时馈电试验以及牺牲阳极等监测治理措施的研究。通过研究,明确了青岛地铁13号线对该管道的直流杂散电流干扰影响范围、影响程度,掌握了管道电位偏移分段、周期性变化以及试片腐蚀速率及特征等基本规律,同时现场验证调整阴保系统输出、增设临时牺牲阳极等缓解治理措施的有效性,制定相应的阴保系统改造、排流缓解治理和腐蚀监测的方案,研究结果可为类似工程提供借鉴。

To address the stray direct current interference on a natural gas pipeline due to Qingdao Metro Line 13,this paper aims to clarify the influence range,degree of impact and corrosion characteristics of metro DC interference,and verify the effectiveness of relevant mitigation measures.To clarify the scope and extent of interference of Qingdao Metro Line 13 DC stray current on the pipeline,and building on the evaluation of the effectiveness of the pipeline s cathodic protection system,site investigations were carried out on mitigation measures on the stray current interference,including field corrosion coupon,temporary power feeding test and sacrificial anode etc.From the study,the following basic rules on the influence became clear,namely the affected area,the extent of the impact,pipeline electrical potential offset segmentation and its periodic changes and fluctuation;and the corrosion rate and characteristics of the corrosion coupon.Meanwhile,the effectiveness of mitigation measures such as adjusting the current output of the cathodic protection system and installing additional temporary sacrificial anodes was verified on site.A corresponding programme of cathodic protection system modification,mitigation by draining stray current and corrosion monitoring was then developed.The result of this research could provide a reference for future projects of the same nature.