Optimization of Cathodic Protection Layout of Oil and Gas Gathering Pipeline Network Based on Finite Element Method

Based on the finite element method to establish an impressed current cathodic protection model, Sobol sensitivity analysis was adopted to determine the key parameters that could significantly affect the cathodic protection effect of a oil and gas gathering pipeline network. The layout of the cathodic protection system was also optimized through the particle swarm optimization (PSO) algorithm. The results show that since the error between simulated potential of the cathodic protection model of impressed current and measured potential of the test pile was small, the model could better reflect the current situation of potential distribution of oil and gas gathering pipeline network. Changing the resistivity of the protective coating and other factors with a higher first-order sensitivity coefficient would have a greater impact on the cathodic protection effect, and there might be obvious interactions between the soil resistivity, the protective coating resistivity, the buried depth of the pipeline and other parameters. When the PSO algorithm was used to optimize the overall cathodic protection effect of the oil and gas gathering pipeline network, the model had an effective coverage rate of 99.14% after 47 700 particle evolution iterations. The optimization effect was remarkable.