Application of deep-well drainage ground bed to the AC interference mitigation of pipelines

With the rapid construction of urban pipeline networks and public corridor facilities in China, the AC interference to buried pipelines from the nearby interference sources (e.g. electrified railway and high-voltage transmission line)is becoming more and more serious, especially the AC corrosion of pipelines. The AC interference of buried pipelines in China is mainly mitigated by means of drainage device + shallow drainage ground bed. As for the interfered pipeline sections in the areas where urban pipeline networks are geographically restricted and those with high soil resistivity (e.g. desert and mountain area), however, the field construction and drainage effect of this method are impacted seriously. The deep-well drainage ground bed is applied in Dalian-Shenyang gas pipeline for AC interference mitigation. It is revealed that if the position, depth and quantity of deep wells and the material of ground bed are selected appropriately, the AC drainage effect will be remarkable with small land area, convenient construction and high drainage efficiency and the damage risk of the third party's construction can be reduced effectively.