In cryogenic environments, it is not possible to apply oil or grease to ball bearings, owing to
the extreme temperature conditions. Thus, polytetrafluoroethylene (PTFE) cages are used as
solid lubricants in such environments, because PTFE has a low coefficient of friction. PTFE
cages increase the rotational stability of the ball bearings by reducing the frictional force of
the rolling elements. In addition, design parameters such as the cage guidance and ball-
pocket clearances significantly affect the stability of the ball bearings. In this study, the …

We studied the dynamic behavior of a ball bearing cage submersed in a cryogenic fluid and
rotating at high speed as a function of the mass imbalance of the cage under various
rotational speeds and light load conditions. The results include the whirling motions and
distribution of whirling frequencies of the cage, the ball bearing torque, and the wear loss of
the ball bearing elements for varying rotational speeds and mass imbalance conditions. The
whirling motion of the cage tended to increase with the increase of the mass imbalance, and …