A Study of the Dynamics of the Rolling Element and its Effect on Outer Race Creep 2016-01-0011
Bearings are a major component in any rotating system. With continually increasing speeds, bearing failure modes take new unconventional forms that often are not understood. In high speed applications, rolling element forces and gyroscopic moments can be significantly high compared to the applied forces acting on a bearing. Such moments create a “driving” torque causing outer race to creep.
In this paper a mathematical model for the dynamics of a rolling element in a high speed bearing is derived. Preload values counterbalancing the torque driving the outer race to rotate can be predicted from this model. An attempt to experimentally measure this torque using a specially designed apparatus with integrated strain gauge torque sensor is also described. Both model and experimental measurements are aimed at understanding, and therefore preventing bearing failures due to outer race (creep) rotations.
Preliminary experiments showed that bearing outer race rotations are reproducible to some degree experimentally. Knowing what makes a bearing outer race moves in an experimental setup will shed a good light on the design parameters and finding ways to prevent it. Focus of the work will be on bearing outer race rotation of an angular contact ball bearing.