Multi-objective optimization of the structural parameters of an allmetal progressive cavity pump based on Grey-Taguchi relational analysis

The all-metal progressive cavity pump (AMPCP) lifting technology can effectively address the challenge of efficiently lifting heavy-oil wells with steam throughput hot recovery. However, design issues have been found to reduce the volumetric efficiency and stability of AMPCP during the process of heavy-oil hot recovery. To enhance the volumetric efficiency and head of the AMPCP, as well as to minimize the impact of turbulent kinetic energy, the Taguchi method was employed to conduct a total of 25 orthogonal experiments involving four factors at five levels. The input parameters included the rotor radius, eccentricity distance, meshing clearance, and the helical pitch of the stator. The output parameters consisted of volumetric efficiency, head, and turbulent kinetic energy. The single-factor effects were analyzed using signal-to-noise ratio (SNR), range analysis (R/S), and variance analysis (ANOVA). Employing the Taguchi method combined with grey relational analysis, the three response objectives were combined into a gray relational grade (GRG). The structural parameter combination that conforms to 95% volumetric efficiency is as follows: rotor radius of 20.5mm, eccentricity distance of 5.1mm, meshing clearance of 0.35mm, and the helical pitch of the stator of 135mm. The simulation results indicate that utilizing Taguchi's method and gray relational analysis for the structural design of AMPCP can enhance its volumetric efficiency and stability.