Abstract: As a key mechanical component providing the stable support in a flywheel, the vibration properties of bearing assemblies have significant influence on the microvibration properties of flywheels. Based on the principle of axial preload on a bearing assembly, a precise rigid preload approach is employed to apply a set of positional preloads on the bearing assembly, and a vibration test system for bearing assemblies is established to capture the vibration properties of the bearing assembly with the preloads. The effects of preloads on the harmonic frequencies, the natural vibration and the ball passage vibration are analyzed. Based on the tests, the effects of the preloads on the vibration properties are analyzed and the optimized regime of the preloads is derived. The reseach suggests the existence of an optimized rigidpreload regime for the bearing assembly.

Key words: preload, bearing assembly, vibration, amplitudefrequency property