Study on Prediction Methods and Optimization Measures of Sucker Rod–Tubing Wear in Screw Pump Wells

Abstract During oilfield development, the wear and failure of sucker rod occur frequently, posing a significant threat to the normal operation and economic returns of the oilfield. In light of this situation, this study addresses the wear problems of sucker rods and tubing in screw pump wells used for oil production. Through extensive research, a model was developed to calculate the axial force and torque of sucker rods. This model allows for a detailed analysis of the complex loads experienced by these components. Moreover, based on the borehole trajectory under three-dimensional working conditions, the force calculation method for sucker rod strings is further enhanced, furnishing precise force data to underpin wear analysis. Leveraging the principle of energy transfer and the most recent wear test data, a highly accurate wear prediction model for sucker rod strings and tubing is successfully devised. Experimental findings validate the model's reliability. Additionally, an investigation into the residual strength of worn sucker rod and tubing is carried out, and corresponding countermeasures for addressing sucker rod and tubing problems are put forward. These encompass optimizing rod structures, adjusting process parameters, and implementing lined tubing. Research outcomes indicate that these measures can notably mitigate sucker rod and tubing wear, prolong their service lives, and offer practical and effective technical solutions for managing rod and tube wear during oil production. Consequently, they hold substantial engineering application value and significance.