Research on Screw Pump Rotor Eccentricitys Influence on Sucker Rod Partial Abrasion through Contact Analysis

Abstract

Through the establishment of contact element simulated the contact between sucker rod and oil pipe. The deformation of sucker rods in oil pipe that caused by the screw pump rotor eccentricity has been researched by the application of transient dynamics analysis. Results show that screw pump rotor eccentricity is one of the reasons which cause rod and oil pipe contact resulting in partial abrasion. Deformation of the sucker rods caused by the rotor eccentricity is mainly concentrated on the bottom of rods, so in order to mitigate partial abrasion, rod centralizer arrangement at the bottom of rods should be strengthened, or change the connection mode between the sucker rod and screw pump rotor to eliminate the effect of the sucker rod deformation caused by rotor eccentric motion.