Abstract: The safety of angular contact ball bearing in CMG under random vibration is investigated. The axial stiffness and radial stiffness of the bearing under both axial force and radial force are derived firstly, then an equivalent linear spring model is established so that the axial force and radial force of the bearing under random vibration can be iteratively obtained using the spectrum analysis of ANSYS. The safety is valuated by comparing radial equivalent static load and axial load with radial base rated static load and limit axial load separately. An analysis of a type of angular contact ball bearing under given input power spectrum density is performed. The result demonstrate that the bearing is safe in any load direction.

Key words: random vibration, bearing, equivalent linear spring model