(1) Excitation due to changes in the number of loaded rolling elements:
When a radial load is applied to a certain bearing, the number of rolling elements that carry the load will change slightly during operation, which causes the load direction to shift. The resulting vibration is unavoidable, but can be mitigated by axial preload, and is applied to all rolling elements (not applicable to cylindrical roller bearings).
(2) Local damage:
Due to operation or installation errors, a small number of bearing raceways and rolling elements may be damaged. During operation, rolling through damaged bearing components generates specific vibration frequencies. Vibration frequency analysis can identify damaged bearing components. This principle has been applied to condition monitoring equipment to detect bearing damage. To calculate the bearing frequency, refer to the calculation procedure "Bearing Frequency".
(3) Accuracy of related parts:
In the case of a close fit between the bearing ring and the bearing housing or the transmission shaft, the bearing ring may be deformed in accordance with the shape of the adjacent component. If deformation occurs, vibration may occur during operation.