Design and Optimization of the Seal Ring of the Retrievable Bridge Plug Based on Improved Genetic Algorithm

According to the demand of exploitating the poor-thin oil layer in Daqing oilfield, retrievable bridge plug is designed. The seal capacity and the clamping function which are respectively accomplished through the seal ring and the slip are the key techniques of bridge plug. For the aim of designing the seals better to generate an effective sealing effect against the well wall, firstly, the sealing structure of retrievable bridge plug is introduced. Then the sealing condition of seals is modeled with ABAQUS software in this paper, including the sensitivity analysis and calculation about the relationships among contact surface and contact pressure and the influence of the structure of seals on them. The elitist non -dominated sorting genetic algorithm NSGA-II has been adopted to do the optimization. Optimum structural parameter is obtained and the performance of withstanding pressure difference is improved. The sealing performance of the retrievable fracture bridge plug in deep well is guaranteed.