Effect Of Lubrication State On Wear And Vibration Characteristics Of Spline Coupling

The spline coupling used in mechanical transmission system is an important basic component,which mainly plays the role of torque transmission during rotation,and is usually a common part of the equipment failure,which also directly affects the operation status and reliability of the transmission system and even the whole machine.Spline coupling in the start and brake process as well as the fluctuation happened in the speed and torque will produce wear and vibration and other problems,and has a direct relationship with the state of lubrication.The main research results include the following four parts.1.This thesis classifies the lubrication state of the spline coupling under oil lubrication,and determines three typical lubrication states: elastomeric lubrication,mixed lubrication and no lubrication state;and analyzes and summarizes the typical wear forms,failure characteristics and wear causes of the spline,and qualitatively clarifies the physical mechanism and change law of the lubrication state affecting the wear;and based on this thesis proposes a method to consider the comprehensive meshing stiffness and comprehensive meshing damping of the spline under lubrication state,establishes a spline coupling dynamics model,and conducts theoretical analysis of the vibration characteristics of the spline coupling under different lubrication states.2.In addition,this thesis investigates the finite element simulation method of spline engagement stiffness and oil film contact stiffness considering different lubrication states in the simulation,and compares the simulation results with the theoretical calculation values to verify the accuracy of the comprehensive spline engagement stiffness calculation.Based on the stiffness results obtained from the simulation,the vibration response of different lubrication states is simulated and analyzed using the established spline coupling dynamics model.3.On the test stand of the mill with spline coupling drive,the vibration test of the mill structure under no load and different rolling conditions was carried out to obtain the acceleration response signal of the roll bearing seat under different lubrication conditions.The spline coupling was disassembled and inspected before and after the experiment,and the contact tooth surfaces were photographed by ultra-deep field 3D electron microscope to analyze the wear morphology of the spline coupling under different lubrication conditions.The correlation between the wear and vibration characteristics of spline in different lubrication states was established based on the actual measurement results.4.Based on the experimental data,the time domain and frequency domain characteristics of the acceleration response signals of the spline coupling in the roll bearing seat under different lubrication states were compared and analyzed,in which the EEMD decomposition of the measured acceleration signals and the clustering characteristics of the cliffness and rms of their reconstructed signals had significant differences.The simulation results are compared with the experimental results and are in agreement.The thesis focuses on the influence law of three typical lubrication states,spring flow lubrication,mixed lubrication and no lubrication,on the wear and vibration characteristics of the spline coupling through theoretical analysis,simulation and experimental test comparison,which provides an important basis for the design,use and maintenance of the spline coupling.