Research On Contact Analysis And Structural Parameter Optimization Of Single Progressing Cavity Pump In Oil Production

Progressive cavity pump mining technology is an important technical means in oil production industry in our country.There are many types of PCP,and the single PCP with the equal wall thickness is one of them.It plays an important role in the submersible progressive cavity pump oil production system and is the key component of the oil production system.This paper takes the single screw pump with constant wall thickness as the research object,studies the influence law of structural parameters on its contact sealing performance,and find the optimal structural parameters,which provides a certain theoretical reference for the optimization design and performance improvement of the single screw pump with equal wall thickness.The main research contents of this paper are as follows:Three-dimensional modeling software is used to simulate the motion of the single screw pump with equal wall thickness,and the influence of structural parameters on the stator and rotor performance of the screw pump is explored.The finite element analysis software was used to explore the contact sealing performance change law of the single screw pump with equal wall thickness under three structural parameters(interference,eccentricity,stator thickness)and four working conditions(pressure difference,uniform pressure,friction,temperature).The order of the impact evaluation index of the screw pump contact sealing performance was obtained through the research results.Multi-objective optimization design of single screw pump with constant wall thickness is carried out based on response surface and NSGA-Ⅱ algorithm.The response surface regression model was established,and the NSGA-Ⅱ algorithm was used to optimize the structural parameters of the single screw pump with the same wall thickness by multi-objective optimization with the minimum total stator deformation,the minimum equivalent stress and the maximum contact pressure as the objective,and the interference,eccentricity and stator thickness as the design variables.The actual working conditions were considered and the constraints were constructed to solve the optimal structural parameters.Verify the optimization results.The results show that the contact sealing performance of the screw pump is improved after optimization.The working characteristics of the single screw pump with equal wall thickness before and after optimization are analyzed by fluid simulation software.The results show that the pressure difference in the cavity of the optimized single screw pump with the same wall thickness is improved,the flow velocity is reduced,and the working performance of the pump is improved.