Investigation of the dynamic local skidding behaviour of rollers in cylindrical roller bearings

Abstract

Skidding has a great influence on the reliability and the life of rolling element bearings. The previous research of bearing skidding mainly focussed on the gross skidding of bearings under severe conditions. However, the local skidding of rolling element also exists and cannot be ignored when bearing normally runs at steady state. In this paper, considering the discontinuous contact between the roller and the cage, the Hertz contact between the roller and races, lubrication, centrifugal effects and the cage pocket clearance, a nonlinear dynamic model is established to investigate the local skidding behaviour of a roller in cylindrical roller bearings. The equations of the dynamic model are solved by the fourth-order Runge–Kutta algorithm and verified by comparing simulation results with the published experimental data. The results show that the local skidding of the roller still noticeably exists in bearings even when the gross skidding can be ignored, especially on the inner raceway. The local skidding at the entry of the loaded zone may cause the smearing on the raceway surface. However, it can be found that the probability of the local skidding of the roller will be decreased by increasing radial load and reducing the bearing rotational speed. The cage pocket clearance would induce violent fluctuations on the roller rotational angular velocity as well as on the sliding velocity. Furthermore, it can generate extraordinary impact forces between the rollers and the cage. Thus, the cage pocket clearance should be carefully considered in the design of bearings.

Correction of Radial Load Distribution Integral for Radial Bearings

“…Moreover, as shown in Table 4 Under the situation of a small load zone caused by a light external load or a great radial clearance, the load distribution plays a significant role in the studies of skidding behaviour [26,28] and the fatigue life [14] of bearings. The sliding velocities of the rollers are considered to exist under light external loads and vary with the radial load distribution in the bearing by Tu et al [26] and Han et al [28]. Moreover, the skidding of the roller at the entry of the loaded zone is likely to cause wear on the raceway surface [26].…”

“…The sliding velocities of the rollers are considered to exist under light external loads and vary with the radial load distribution in the bearing by Tu et al [26] and Han et al [28]. Moreover, the skidding of the roller at the entry of the loaded zone is likely to cause wear on the raceway surface [26]. Thus, accurate calculation of the load distribution under light load condition can be used to ensure the skidding states of the rollers and the locations of the possible wear.…”

“…It indicates that the current integral method is not applicable for the small load zone situation caused by the light external load or great clearance [1]. The skidding of the rolling elements often occurs and results in smearing type of surface damage under light load situation [26], while the bearing tends to early failure operating with a great clearance [14].…”

Numerical simulation to research the collision and skidding of rolling elements for cageless bearings

“…Han and Chu (2015) presented a dynamic model to predict the skidding behaviour of ball bearings. Tu et al (2019) investigated skidding during the rolling element bearing acceleration considering the discontinuous…”

“…Han and Chu (2015) presented a dynamic model to predict the skidding behaviour of ball bearings. Tu et al (2019) investigated skidding during the rolling element bearing acceleration considering the discontinuous contact between the roller and the cage, Hertz contact between the roller and races, lubrication, centrifugal effects and cage pocket clearance. Fang et al (2018) proposed a comprehensive mathematical model to predict the skidding behaviour of ball bearings considering the effects of the interaction of the rolling element with the raceway, cage and lubricant and the interaction of the cage with the inner and outer raceways.…”