Optimization Of Logarithmic Convexity Profiles For Bearings Rollers In Trucks Wheel

With the rapid development of modern industry, the bearings are widely used in all kinds of mechanical equipment. The life of bearing plays an important role for machine. When a bearing roller is contacting with raceways, the stress concentration at the end of rollers inevitably occurs-"Edge Effect". In order to overcome the edge effect, the crown design method was employed. Due to the heavy load and bad working condition of the roller of bearing33022, the edge effect of bearing working surface becomes more obvious. By optimizing the crown of bearing, the edge effect is reduced and the life of bearing is improved.(1) The optimal convexity of symmetric convexity at the rated load is Studied. The crown design of the bearing include two components. Chosing of the crown type and designing the crown amount. A crown design method proposed by Hiroki Fujiwara and Tatsuya Kawase is used to investigate the crown of the roller of bearing33022in this paper. According to the size of bearing, a two-dimensional FEM model of the inner and out raceway being straight line and the roller being the logarithmic curve are established. The different contact stress of tapered roller bearing are calculated under different crown of the roller. At rated load300KN, the maximum contact pressure is minimum and the crown is optimal under the conditions of k1=1.2、 k2=0.5、Zm=0.007mm.(2) The optimal convexity of asymmetric convexity at the rated load is obtained. Due to the influence of installation angle of bearing and taper angle of roller, the bearing suffers "misaligned load effect". A method based on asymmetry design of roller crown is proposed in this paper, that is the heavy load end has a bigger crown and the light load end have a smaller crown. The contact stress is calculated by FGM according to the different crown of the roller. If k1=1.2、k2=0.5、Zm=0.009-0.006mm. the stress difference between the maximum contact stress and minimum stress is smaller. The results show that crown optimal has significant contribution in reducing the "edge effect" and "misaligned load effect"(3) The optimal convexity of asymmetric convexity at the different load is got. Considering bearing33022sustains different load under different working conditions, when Fr=0.15Cr, Fr=0.20Cr, Fr=0.25Cr, Fr=0.30Cr, Fr=0.35Cr, using asymmetry design of roller crown, the optimal designed crow is obtained under different load.