The objective of this study was to investigate the dynamic behaviour of healthy and defective cylindrical roller bearings to understand the response of these bearings to various operating conditions as a non-destructive diagnostic tool that is the modal analysis. The frequency and phase responses have been measured using a Coco-80 FFT analyser and repeated tests have shown that the values are reliable. The experimental and Finite Element (FE) simulated responses were compared and good agreement was obtained overall with some differences in natural frequencies. The differences were explained due to modelling and measurement procedures, non-linearity and small geometric differences between the measured and modelled bearings. Defective bearings showed less amplitude of acceleration in natural frequencies and harmonics and phase angle deviations at certain frequencies. These changes are associated with defects like cracks, voids, notches and/or material impurities which interfere with the continuous propagation of vibration energy. The results validate the effectiveness of using frequency response analysis, along with validated Finite Element (FE) simulations, for early fault detection and predictive maintenance of rotating machinery. This paper presents the results of the modal analysis carried out on a cylindrical roller bearing using the Frequency Response Function (FRF) for early fault detection and predictive maintenance.
Themba Mashiyane (Wed,) studied this question.