Study of the degradation of rolling element bearings with artificial dents

Contact fatigue in rolling element bearings (REBs) is a common surface degradation and failure mechanism. A better understanding of this process, especially the evolution of tribological features and resultant dynamic responses, is critical for developing effective tools to monitor degradation and predict remaining useful life. This paper investigates the relationship between the geometry of seeded faults – specifically their shape and size – and bearing performance under grease-lubricated conditions. Two bearings with different fault shapes and sizes were tested. To study the degradation process, moulds and images of the fault area were collected at different intervals to capture the gradual progression of wear. The acceleration root mean square (RMS) value of vibrations was used as a real-time indicator to detect significant changes in bearing dynamics throughout the degradation process. This study provides valuable experimental data and insights into the degradation processes of rolling element bearings when they are subjected to initial defects related to manufacturing or contamination, under grease-lubricated conditions. This knowledge is crucial for developing effective real-time techniques for monitoring the degradation process.