A Bearing Endurance Life Prediction Method Considering the Bearing Dynamic Characteristics 2015-01-0494

A rotating bearing must have an excellent durability life. Various studies have been conducted for a long time to predict the bearing durability life. However, the bearing durability life has been predicted by an analytic formula in terms of the raceway and ball. A finite element structural analysis has been carried out for a flange, commonly with an assumption of a static load. So it is difficult to consider the dynamic effects (Centrifugal force, Gyroscope effect) of the bearing, which is very important due to its high speed operation.

In order to predict the accurate bearing durability life, the dynamic effects must be considered. This paper proposes a method for bearing durability life prediction, considering dynamic effects. Contact between the raceway and ball is one of the important factors to take into account for the dynamic effects of the bearing. General surface to surface contact method is not appropriate for the bearing analysis because it produces a noisy and spiky contact force. This research develops a specialized contact algorithm for a bearing analysis to efficiently obtain the dynamic load which is a key factor to predict the accurate bearing durability life. The contact forces obtained from the algorithm is used to predict the bearing durability life.

The bearing durability life obtained from the proposed research is compared with this obtained from the analytic formula and static load by using DAFUL (a commercial structural dynamics software). Also several case studies have been carried by setting up scenarios to predict the bearing durability life.