Research on the effect of inner raceway defects on the stiffness characteristics of rolling bearings

Rolling bearings are widely used in mining motors and other large equipment. Under complex and changeable working conditions and harsh operating conditions, long-term and high load operation will lead to fatigue pitting corrosion of rolling bearings and defects on raceway surface, and the deterioration of defects will affect the normal operation of equipment. In this paper, for rolling bearings with defects in the inner raceway, the additional displacement caused by the defect is added to the elastic deformation of the bearing. According to the mechanical balance equation, the load distribution of each rolling element is analyzed, and the stiffness model of the rolling bearing with defects in the inner raceway is established. The influence of defect length and depth on rolling bearing stiffness characteristics is analyzed. The results show that when the defect is located in the non-loaded area, the average stiffness of the defective bearing is equal to the average stiffness of the non-defective bearing. When the defect moves from the loaded area to the non-loaded area with the rotation of the inner ring, the average stiffness of the bearing first decreases and then increase, and the average stiffness is negatively related to the length and depth of the defect.