Research On The Lubrication Performance Of Static And Dynamic Thrust Bearing With Different Cavities Under Eccentric Load

As one of the core components of modern heavy CNC machining equipment,the lubrication performance of static and dynamic thrust bearing will affect the working stability and machining accuracy of CNC machining equipment.When the bearing is in the ideal working state,the centroid of the workpiece to be machined is located at the rotation center of the static and dynamic thrust bearing.However,in the actual working process,due to the influence of factors such as different workpiece shapes or deviation in workpiece clamping,the centroid of the workpiece deviates from the center of the workbench in the vertical direction,so the workbench will appear eccentric loading.When the eccentric load of the worktable is light,the oil film thickness in the local clearance will become thinner and the maximum temperature will rise,excessive eccentric load will lead to dry friction of the bearing,reducing the service life of the bearing.In this thesis,the influence of various factors on the lubrication performance of the static and dynamic thrust bearing under the eccentric load condition will be explored from the factors such as the shape of the oil cavity,the offset distance,and the load.Firstly,the oil supply mode of the static and dynamic thrust bearing will be selected.According to the hydrodynamics and lubrication theory,the flow,bearing capacity,temperature rise,and the matching relationship between speed and load of the sector cavity,runway cavity,and double rectangular cavity under the eccentric load condition will be established.Secondly,fit the viscosity and temperature relationship equation of HL-46 lubricating oil,calculate the oil film thickness of each cavity under eccentric load condition,and use SOLIDWORKS software to establish the three-dimensional models of the oil film of the sector cavity,runway cavity and double rectangular cavity of the static and dynamic thrust bearing under the eccentric load condition,use the ANSYS CFD module to mesh the three-dimensional models of the oil film of different cavities,and merge the whole grid.Finally,CFX module will be used to set boundary conditions on the grid model and carry out simulation.Through post-processing analysis,the clearance oil film pressure field and temperature field of sector cavity,runway cavity and double rectangular cavity of static and dynamic thrust bearing under different offset distances,different loads and different speed conditions will be obtained.The influence of different factors changes on the pressure and temperature characteristics of static and dynamic thrust bearings will be analyzed,it will provide a theoretical basis for further research on static and dynamic thrust bearing under eccentric load.The static and dynamic compaction test bench will be used to verify the pressure field and temperature field of the static and dynamic thrust bearing under the eccentric load condition.The simulation data will be compared and analyzed with the experimental data to verify the correctness of the pressure field,temperature field and their distribution laws,and prove the rationality of the simulation method.