Trans-Scale Modeling And Non-Hertzian Contact Analysis For Deep Groove Ball Bearing

Deep groove ball bearing is the most commonly used load-bearing component in automotive transmission.It is not only a moving connector,but also a load support when it works.Its motion and stress state are very complex.The main failure modes of deep groove ball bearings,such as contact fatigue,friction and wear,pitting,peeling and gluing,are closely related to the contact state between ball and raceway.Therefore,it is important to study the true contact state between the ball and the raceway of the deep groove ball bearing.By writing MATLAB program and combining the characteristics of finite element before and after processor,this paper realizes a finite element simulation method which can improve the solution precision and save the computer solution time.It is called trans-scale finite element modeling method.It is used to solve the problem that the calculation accuracy and efficiency of the bearing ball raceway contact can't be achieved by using the finite element method.Taking the three-dimensional Hertz point contact problem of two elastic hemispheres as an example,it is proved that the accuracy of solving the three-dimensional contact problem using the trans-scale finite element method can meet the actual engineering requirements.The research in this paper is closely combined with the engineering practice.Taking the premature failure of a deep groove ball bearing inside a three-axis transmission as the research background,the support bearings of the transmission under the maximum torque limit conditions such as first gear and reverse gear are calculated.The external load confirmed that the most heavily loaded deep groove ball bearing was the bearing that failed prematurely in the transmission bench test.Subsequently,the finite element model of the most heavily loaded deep groove ball bearing was established.Considering the effects of radial and axial loads,clearance,cage alignment,elastic and gravity of the bearing components,using the true plastic material constitutive,the bearing load distribution under quasi-static conditions was simulated.Then,the ball and raceway with the largest load are taken as the analysis object,and the high-precision contact simulation under static conditions is carried out by using the trans-scale finite element modeling method.The true contact state of the ball race is obtained.The influence of material constitutive model,load size and direction on the true contact state of the bearing ball raceway is further studied.Finally,the finite element method is used to simulate the ball load distribution under transient conditions for the most dangerous bearing under extreme conditions.The bearing size and its variation law of each ball under transient conditions are obtained.Furthermore,the variation law of bearing ball and raceway equivalent stress is analyzed,which provides a basis for the analysis of bearing failure causes.Subsequently,the trans-scale finite element method is used to simulate the contact between the ball and the outer race under transient conditions,and the exact value of the equivalent stress is obtained.The equivalent stress of the ball and raceway is corrected based on this.Finally,the failure reason of the bearing is analyzed by combining the variation rule of the equivalent stress of the bearing and the simulation results of the trans-scale contact model under transient conditions.