Research On The Influence Of Point Supported Tilting Pad Thrust Bearing Structure On The Lubrication Performance

The thrust bearing can bear the axial load on rotating machinery,and plays an important role in many mechanical equipment.With the progress of science and technology,the development of mechanical equipment towards to large-scale and heavy duty,and the requirements of bearing performance become more strictly.Therefore,improving the bearing performance and working life are particularly important.Among of many different structural bearings,the point supported thrust bearing is widely used.For improving the performance of the point supported thrust bearing,this paper studies the effect of some parameters on the lubrication performance of bearing,like the point supported position of the thrust tile,the deformation of thrust tile and so on,and the effect of single pallet on the deformation of the thrust tile is also studied.In this paper,based on the theory of lubrication,the mathematical model of fluid lubrication of the point supported tilting pad thrust bearing is established,and obtaining the boundary condition of the basic equation.Firstly,the mathematical model of bearing fluid is solved by finite element method.Based on the calculation program of bearing lubrication compiled by FORTRAN language,the influence of the fulcrum position,the deformation of thrust tile and the temperature of oil groove on the bearing lubrication performance is calculated under various working conditions.The optimum fulcrum position is determined by the minimum oil film thickness parameter,and its distribution is analyzed.Secondly,the effect of the size and position of the pallet on the deformation of the thrust pad is analyzed by the ANSYS Workbench software.The results show that: The reasonable supporting point position can improve the lubrication characteristics of thrust bearing obviously.The optimum supporting point position is close to the outside of bearing pad in radial direction,and its radial eccentricity decreases with the increasing of specific pressure,rotating speed and aspect ratio,increasing with the bearing pad deformation increasing;The optimum supporting point position is close to the oil outlet side in circumferential direction,and its circumferential eccentricity increases with the increasing of rotating speed and aspect ratio,decreasing with the increasing of bearing pad deformation and specific pressure,and the lubrication performance of the bearing is optimal when the bearing deformation degree is about 1.With the increase of pallet size,the thrust tile is changed from convex deformation to dish shape,then from the wavy shape to the whole concave deformation for the point support thrust pad with single pallet;The thickness of the tile has a great effect on the adjustment of deformation of the thrust pad,the reasonable match between the thickness parameters of the thrust tile and the size of the pallet should be paid attention to the design.Finally,the correctness of the calculated results is verified by experiments.