A Parameter Optimization Simulation Method for Crank Torque of Double Horse Head Pumping Unit Dynamics Model with Cable

摘要

Background: Patents revealed that Double Horse Head (DHH) pumping unit is one of theimproved models developed from the conventional units, and some unbalanced crank torque may causehigh cycle alternating stress which can lead to cracking failure in some key components. This makes theresearch on simulation of crank torque in beam pumping units a more interesting topic in its maintenanceoperation.Objective: This paper aims to improve the accuracy of crank torque simulation model for the DHHpumping unit by a parameter optimization method for cable joints.Methods: By using a series of cylinders to model the steel cable, a pumping unit multibody dynamicsmodel was constructed to simulate the crank torque. Then the stiffness and damping coefficient in bushingjoint and contact force of cable were treated as the key factors, and a Genetic Algorithms based themethod was proposed to optimize them for improving the simulation accuracy of the model.Results: This method was applied to simulate the crank torque of a DHH pumping unit, and the experimentaltorque was also tested from real unit. Results show that the crank torque simulated from improvedmodel is much closer to the experimental tested torque compared with the original model.Conclusion: The parameter optimization method proposed in this paper greatly improved the accuracyof simulated crank torque in DHH pumping unit multibody dynamics model.