Analysis and experimental research of hydrostatic spindle oil film slip phenomenon

For the problem of dynamic characteristics of the hydrostatic spindle in the process of movement, the impact that oil film slip on bearing capacity, stiffness and dynamic stiffness is researched. Introducing the velocity slip boundary conditions, the hydrostatic spindle load-bearing characteristic equation combined with liquid flow equation form a coupling equation system. The bearing capacity, stiffness and dynamic stiffness of spindle system are numerically analyzed. The spindle static and dynamic properties and oil film dynamic stiffness characteristics are researched in the initial stage of oil film. It is concluded that the occurrence of oil film slip results in the increase of bearing capacity and stiffness from the simulation results, the corresponding oil film thickness with the maximum stiffness is reduced. The existence of slip phenomenon is obtained in the oil film flow process of spindle system. This study explores a new way for the analysis of hydrostatic spindle oil film static and dynamic performance and the research of dynamic stiffness.