Research on Stray Current Commutation and Anti-Corrosion Layer Breakdown Protection Nearby Oil and Gas Pipelines

Due to the shortage of industrial land in China, the phenomenon of parallel erection of power lines and oil and gas pipelines is common. Lightning strikes may cause overvoltage problems in oil and gas pipelines. In this paper, a breakdown protection strategy for the anticorrosive coating of oil and gas pipelines based on the external application of the tower foundation is proposed. The COMSOL Multiphysics simulation software is used to model and calculate the ' cage ' external grounding device of single pile and four-pile concrete foundation respectively. The influence of soil resistivity and external application area on pipeline overvoltage under the condition of single pile concrete foundation is analyzed. The advantages and disadvantages of external application and laying artificial grounding electrode under the condition of four-pile concrete foundation in pipeline protection are compared, and then the optimization strategy of ' cage ' external application of concrete foundation with flexible graphite composite grounding material is proposed. The simulation results show that the increase of soil resistivity will increase the peak value of pipeline overvoltage. The increase of the external application area can reduce the overvoltage of the pipeline ; the ' cage ' type external application of concrete foundation is better than the traditional concrete foundation with artificial grounding electrode to reduce the overvoltage of pipeline. The relevant research and conclusions of this paper can provide reference for the design and construction of oil and gas pipeline protection.