西南山区管道埋设地质条件复杂，运行难度系数大，土壤性质变化多样且腐蚀性普遍较强。由于山区管道路由的限制性，原油管道、天然气管道、成品油管道在同一管道廊带并行敷设，最小间距不到1.5 m，并行方式存在同沟敷设、同路由敷设2种情况，每条管线均采用独立的阴极保护系统。针对该情况，检测了西南山区并行管道沿线共5座站场及14座阀室，结果发现：站场区域阴极保护对并行管线阴极保护系统干扰影响较大；油气合建的站场和阀室的线路阴极保护系统之间引起的干扰更普遍；并行管道相互干扰的范围有限，通常距离阴极保护系统约3 km左右其干扰引起的通电电位变化已经小于50 mV。
The geological conditions of buried pipelines in southwest mountainous areas are complicated, the operation difficulty coefficient is large, the soil properties vary, and the corrosion is generally serious.Due to the restrictive routing of pipelines in mountain, the crude oil pipelines, gas pipelines and product oil pipelines are laid in parallel in the same pipeline corridor.The minimum separation distance is less than 1.5 meters.The parallel mode is laying in the same trench and laying in the same route.The independent cathodic protection system is used for each pipeline.In response to this situation, 5 stations and 14 valve rooms along the parallel pipelines in the southwest mountainous area were detected.It was found that cathodic protection in the station area had great impact on the parallel pipeline cathodic protection systems, interference between the oil and gas combined station and the valve cathodic protection system of the valve room is common.However, the range of mutual interference of parallel pipelines was limited, usually about 3 km away from the cathodic protection systems the change of the on-potential caused by the interference was less than 50 mV.
