Simulation And Optimization Of Pumping Unit With Double Crank Type 2K-H Gear Train Reversing Device

In order to meet the current high-efficiency production of oilfields in my country,the oil field has put forward the requirement of long stroke and high efficiency for the pumping unit.Among the many forms of long-stroke pumping units,the drum pumping unit is ideal in application,but the main reason that troubles the development of this model is the poor reliability of the reversing mechanism.In this paper,the scheme design and optimization simulation are carried out for the drum pumping unit system.Based on an antiparallel-crank mechanism and a 2K-H planetary gear train with parallel input of gears,a single-degree-of-freedom mechanical transmission rotation reversing device is designed.Based on the new rotary reversing device and the suspended weight balance scheme,a tower pumping unit is designed.The new pumping unit has the advantages of reliable mechanical commutation,large output swing angle,and easy realization of long stroke.The analysis model of the kinematics of the new pumping unit reversing device and the motion law of the suspension point is established;according to the kinematics model,a coupled simulation model of the single-degree-of-freedom rigid component system dynamics of the pumping unit ground drive and the longitudinal vibration of the sucker rod string is established.On the basis of the system kinematics and dynamics simulation model,the torque calculation model of the reversing device is established,and the motion and dynamic characteristics of the system are analyzed.Based on the finite element method and the lumped parameter method,considering the nonlinear factors such as gear meshing stiffness,gear meshing error,system transmission damping coefficient,etc.,a double crank-gear train coupling torsion nonlinear dynamic model is established.Based on this model,the natural frequency and system dynamic response of the parallel system of double crank and gear train are simulated and analyzed.It is found that the system has jumping and chaotic phenomena,and the important influence of the double-crank mechanism on the vibration response of the system is determined.Based on mechanical optimization design theory,according to rigid dynamics and torsional dynamics models,taking the minimum weighted average value of root mean square driving torque and structural parameters as the optimization objective function,the mechanism parameter optimization and structural parameter optimization models of the pumping unit are established.The optimization results show that,compared with the beam pumping unit,the new pumping unit has energy-saving effect.