Dynamic Simulation Of Reduction Gearbox Transmission System In Beam-Pumping Unit

The beam pumping system is the most commonly used rod pumping system. Reduction gearbox is one of the pivotal parts in the beam pumping system. The large transfer torque on the crank shaft of gearbox in pumping unit has high fluctuation and negative which lead to the energy loss and the transmission efficiency reducing. In this case, study the simulation models of dynamics and transmission efficiency of reducer casing transmission system in pumping unit has significant academic value for depth investigating dynamic simulation of the beam pumping system and improvement accuracy of system efficiency.This paper focuses on the following tasks:This paper has completed entity modeling of gearbox in beam pumping unit at 53 kN.m by applicating Pro/E software. It laies the foundation for the mathematical modeling of concentrated masses, stiffnesses and any other parameters. These parameters are included in the mechanical transmission system dynamic simulation model.Mechanical and mathematical models are established of torsional vibration of reduction gearbox transmission system in beam pumping unit with considering the combined influence of the time-varying meshing stiffnesses, meshing damping, fluid damping and external loads etc. Meanwhile, gears are simplified as concentrated mass discs, and the gear axises are reduced to elastomers.Based on the established torsional vibration mechanical model of gearbox drive system, this paper creates the lateral-torsional coupling vibration mechanical and mathematical models of the gear reducer transmissionlystem in beam pumping unit with considering the influence of bending deflection of transmission shaft to the torsional vibration of the decelerator powertrain system.Based on the force parameters of the simulation results which are contained in the torsional vibration and lateral-torsional coupling vibration, this paper establishes transmission efficiency of gearbox drive system.Taking the software of matlab R2007 as simulation platform , this paper makes an analysis on the natural frequency by the subspace iteration method, modal response, stationary response and the transmission efficiency ,which are summed up in the torsional vibration and lateral-torsional coupling vibration.At the same time, analyse the influence of meshing stiffnesses, meshing damping, and external loads to them. At last,the simulation result of transmission efficiency of two models are compared,and demonstrate that the influence of bending deflection of transmission shaft to the torsional vibration is not neglected.