Finite Element Analysis Of Rolling Bearing With Various Defects Aimed At Stress And Strain

In the process of bearing design and analysis, the load carrying capacity, lifeexpectancy, fatigue damage, stiffness, vibration and noise, etc. problems are closelyrelated to bearing stress distribution and deformation condition. Therefore, through thecontact analysis, a good grasp of the bearing contact surfaces’ stress distribution anddeformation characteristics provides the effective theoretical basis for improvingdesign and processing techniques, the load carrying capacity and reliability of bearingsystem.Based on the main working platform of the universal finite element softwareANSYS, this paper studies the nonlinear statics characteristics of the ball bearing withpoint defects, elliptic defects，and the nonlinear dynamic characteristics of ballbearing with defects. Firstly, this paper establishes the statics finite element model ofthe maximum load-bearing steel ball and makes a comparison with the results of hertztheory, which shows that the analysis results of finite element method meet practicalengineering needs. Then, this paper establishes the finite element models of ballbearings with point defects in outer ring and elliptic defects of raceways, aiming tomake a comparison with the stress and strain of ideal bearing. Last, this paperestablishes the finite element models of ball bearings with point defects with differentdiameters in outer rings to research which influences the change of point diametershave on stress, strain and vibration characteristics.Through the research, this paper gets the following conclusions that the peak ofvon mises stress appears in a point under the contact surface, which provides atheoretical support for the fatigue spalling of rolling bearings. Peach shape racewaymakes single elliptical contact into double contacts, which changes the distribution ofcontact stress of inner ring and reduces the deformation. Inverse elliptic defect will getthe the maximum stress of outer ring increase. The shape of the raceways hasimportant influence on the stress and deformation. Through analysis of point defects with different diameters, we can get the following conclusions that with the increase ofdefects diameter, the maximum stress at defects point will reduce. The bigger thedefects diameter is, the stronger the vibration of the inner ring and ball is. Thevibration of ball is stronger than that of the inner ring. In the rolling process of bearing,the probability density function is constantly changing, which shows that the vibrationcharacteristics of bearing is uncertain and nonlinear.In this paper, the simulation based on the finite element analysis visually revealsthe causes of the fatigue spalling and the original failure feature, the impact of pointdefects on stress, strain and vibration. Research shows that the mises stress at the pointof point defects is huge when point defect diameter is relatively small, that pointdefects diameter will expand after the effect of alternating load, and that the vibrationand impact of bearing will be stronger with the increase of defects diameter, resultingin more point defects and then bearing failure.