Analysis Of Contact Characteristics Of High-Speed Angular Contact Ball Bearings

Angular contact ball bearings are widely used in rotating machinery because of their high speed,high precision and can bear combined load.In the actual operation of bearing,it is impossible to keep the healthy state when it leaves the factory.Some researches have found that fatigue is the main problem of bearing.Therefore,it is necessary to simulate the contact behavior of the bearing when the surface of the inner and outer rings is cracked early in the bearing design and use.In this paper,the contact characteristics of angular contact ball bearings at high speed are analyzed from three aspects.Firstly,the quasi-static model of angular contact ball bearing under normal condition is established by Hertz’s contact theory,and a new idea is proposed to solve the model.Based on the quasi-static model,the effects of the inner ring speed,axial load and radial load on the contact angle,contact load,contact stress and stiffness of the bearing are studied,the relationship between bearing stiffness and component life under variable operating conditions is described qualitatively.Then,the quasi-static model of angular contact ball bearing with single-point early crack in inner ring and outer ring is established.The effects of different working conditions on the contact characteristics of angular contact ball bearings under different damage locations,damage sizes and radial force directions are studied.It is found that:(1)adjusting the outer ring damage to the position of 90°will help to restrain the influence of crack damage,and the radial stiffness of the bearing is slightly strengthened.(2)increasing the rotational speed can reduce the speed of damage propagation at the expense of bearing stiffness.Finally,by comparing the contact characteristics of the inner and outer ring under the same condition,found that the damage of the outer ring has greater influence on the bearing than that of the inner ring,however,the damage of inner ring has a greater influence on the non-damaged position of bearing area than that of outer ring.Therefore,the outer ring should be more resistant to stress fatigue materials in order to ensure the effective use of bearings.