Effect of the raceway defects on the nonlinear dynamic behavior of rolling bearing

The defects on raceways would aggravate the vibration of bearing and greatly influence the bearing performance, in order to monitor the running state of the bearing and detect the early defect, the characteristics induced by the defect must be explored. This paper establishes a bearing dynamic model to explore the effect of raceway defects on the nonlinear dynamic behavior of rolling element bearing. The interaction between ball and races is modeled based on Hertz theory, while the presence of defects changes the ball-race interaction. The effects of defect size, position and number on bearing dynamic behaviors are investigated with the aid of phase trajectories, shaft center orbits, FFT spectra, etc. The results indicate that the defects can make the motion of the system more complicated and induce vibration at some characteristic frequencies, which can be used to recognize the bearing failure at early stage. The proposed research provides useful information for the design and status monitoring of mechanical systems.