Dynamic Modeling And Analysis Of Rolling Bearings With Point Corrosion Defects

As an indispensable part of rotary machine,the running state of the bearing directly affects the running state of the machine.The mechanism of fault are the basis of mechanical fault diagnosis,and the research of fault mechanism can provide theoretical guidance for fault diagnosis.The establishment of dynamic model of defect bearing has important theoretical value and engineering significance for fault diagnosis of rolling bearing.In view of the above problems,the relative sliding between the ball and the ring is considered,and the dynamic model of the inner,outer ring and rolling elemnt with point corrosion defects bearing is established.Firstly,the lubrication traction model between the ball and the ring is established because the relative sliding between the ball and the ring is seldom considered in the present dynamic model of bearing,and the interaction force between the ball and the ring in the bearing is determined through the establishment of the bearing coordinate system.The dynamic response of the normal rolling bearing is analyzed by establishing and solving the dynamic equation of the bearing.Then,based on the normal rolling ball bearing dynamics model,considering the process of pitting corrosion defect deformation gradient,according to the size of the ball through the ring injury situation is classified and discussed respectively when establishing the outer ring,inner ring and ball bearing damage dynamics model.In this paper,the vibration response characteristics of bearings with different damage locations are studied,and the spectrum distribution of bearing is given and compared with the pure rolling theory,and the effect of relative sliding on vibration response of fault bearing is expounded.The dynamic model of the bearing with different damage is established,and the influence of the damage size is analyzed.On this basis,the vibration test experiments of the fault bearing are designed and carried out.The vibration response characteristics of the outer ring deect bearing and the inner ring deect bearing are measured respectively under different rotation frequencies,and the results are compared with the simulation results.The accuracy and reliability of the simulation model are proved and the relative slippage between the ball and the ring in the bearing is verified.Therefore,the dynamic model established in this paper will provide a more accurate diagnostic basis for rotating machinery bearing fault diagnosis.