Research Information System
Journal of Vibration Engineering and Technologies, vol.13, no.6, 2025 (SCI-Expanded)
Rolling bearings are the most common type of bearing in rotating mechanical systems, from household appliances to aeronautical systems. Therefore, monitoring the vibrations of the system and investigating its condition is necessary for efficiency and predictive maintenance. In this study, the correlation between the speed variation of the shaft driven by an electrical motor and the condition of the ball bearing supporting the shaft is investigated. The condition of the ball bearing is determined by analyzing the measured vibration using the time and frequency domain techniques. A test rig was designed and manufactured to feature a pair of new ball bearings to support the shaft. The system is operated throughout its lifespan using a variable speed drive (VSC) set to constant parameters, and the loading condition is also not changed. Shaft speed data and vibration signals are acquired and recorded using a data acquisition system. Statistical and signal processing techniques are applied to test data based on spectral kurtosis and envelope spectrum analysis. The results show that there is a strong correlation between shaft speed fluctuation and the condition of the bearing. Therefore, the suggested method can be used to detect and identify faults, estimate the generated fault of a bearing from the vibration data in real-world industrial applications. Finally, this paper shows the importance of motor speed monitoring in predictive maintenance and reliability of the rotor and bearing.