Study On Dynamic Modeling Of Cylindrical Roller Bearings With Real Waviness And Waviness Order Prediction Method

Rolling bearing is an important mechanical basic component,Their application in modern machines is very common.The running state of rolling bearings will directly affect the performance of mechanical equipment.Bearing vibration is an important standard for evaluating the performance of a bearing rotor system.It has a non-negligible impact on the accuracy and reliability of the drive system.Therefore,the demand for bearings in modern equipment is toward high precision,low vibration,and low noise.The waviness of the bearing,that is,the surface unevenness that randomly or periodically deviates from the ideal sphere,is caused by the vibration during the grinding process.Bearing waviness is the main factor causing bearing vibration and temperature rise.Studies have shown that in the geometric accuracy of bearing parts,waviness has the greatest impact on bearing vibration.However,at present,for the study of bearing waviness,the surface waviness of bearing parts is often expressed as a sine function to discuss the vibration characteristics of the bearing outer ring,But less research on the real waviness bearing vibration characteristics prediction;most researches are concentrate on bearing inner race and outer race waviness,but few study on the roller waviness excited vibration and bearing roller vibration caused by bearing components waviness.In order to improve the bearing waviness vibration theory,this paper proposes a bearing dynamic modeling method based on real waviness of the bearing,which can be applied to the prediction of the vibration characteristics caused by inner race waviness,outer race waviness and the rollers waviness.The influence of the real waviness of the outer race,the inner race and the rollers of the bearing on the vibration characteristics of the bearing is analyzed and studied,and a waviness orders prediction method based on bearing vibration signal is proposed.The main research contents of the paper are as follows:(1)The kinematics of bearings,Hertzian contact mechanics,and the basic theory of elastohydrodynamic lubrication are used,and the dynamic model of a cylindrical roller bearing is established based on the Lagrange equation.The interpolation re-sampling method was used to obtain the real waviness function of the parts of the bearing,the coupled cylindrical roller bearing dynamic model,and the outer race vibration equations and the rollers vibration equations of the real waviness bearing were derived.Lays the foundation of real waviness bearing dynamic analysis.(2)Using the dynamic model of the real waviness cylindrical roller bearing established in this paper and the dynamic equations,The simulation calculation of the vibration characteristics of the bearing roller and the outer ring were achieved respectively under the excitation of the the real waviness of the bearing rollers,the real waviness of the inner race,and the real waviness of the outer race at different shaft speeds and radial forces,comprehensive use of frequency spectrum analysis,envelope analysis and vibration energy analysis methods to study the amplitude-frequency characteristics of the vibration of the bearing caused by changes in stiffness,namely the variable flexural vibration,and the influence of bearing shaft speed and radial force on the amplitude-frequency characteristics of the variable flexural vibration of the bearing and the vibration caused by the real waviness.(3)Select bearings and complete the vibration test at different speeds to obtain the vibration signal of the real waviness bearing.The vibration characteristics and dynamics of the outer ring of the real waviness bearing are obtained by using Fourier transform and envelope analysis.The comparative analysis of the vibration characteristics obtained from the simulation and experiment has verified the correctness of the dynamic model of the real waviness cylindrical roller bearing established in this paper and the correctness of the conclusion obtained from the simulation analysis.(4)Select multiple sets of cylindrical roller bearings with different waviness orders.Using the dynamic model of the real waviness cylindrical roller bearings established in this paper,complete the simulation calculation of the vibration characteristics of the outer ring caused by rollers real waviness,the inner race real waviness and the outer race real waviness,analysis and obtained the relationship between the waviness orders of the inner race,outer race and rollers and the frequency domain characteristics of the bearing outer ring vibration,and then proposed a bearing waviness orders prediction method based on the vibration signal of cylindrical roller bearings.The dynamic model of the measured waviness cylindrical roller bearing proposed in this paper can be used to predict the vibration of the waviness bearing,and the calculation is fast and accurate.The bearing vibration characteristics of the bearing caused by the roller,the inner race and the outer race real waviness and influence of the shaft speed and radial forces were analyzed.provides a theoretical basis for the improvement of the design and manufacture of low noise bearing.The waviness orders prediction method of the bearing based on the vibration signal provides a more rapid,effective and accurate method to measure the waviness parameter of the bearing.Which has a certain academic significance and engineering value.