Research On Impact Of Reinforcing Plate On Thermal Deformation Of Worktable Of Hydrostatic Bearing

Heavy hydrostatic bearing is one of key equipments in national equipmentmanufacturing industry. Because of heavy load, high rigidity and high stability, it hasbeen widely used in machinery manufacturing industry. Besides, its precisiondirectly reflects manufacturing level of whole manufacturing industry. Worktable asone of all parts of hydrostatic bearing directly contacts with workpieces, so itsperformance will directly affect machining accuracy and machining efficiency.Worktable is, as an important component in machining, if it produces deformation, itwill have an enormous impact on machining accuracy. The deformation due tothermal load accouts for a quite big proportion in all deformations, and is even mainfactor. If thermal deformation is large enough, machining process will fail. Soresearch on thermal deformation field has great practical significance for productmanufacturing.Used object in this paper is worktable of heavy vertical lathe DVT1000×50/150Q-NC. This machine is used to manufacture large-scale parts with greatweight, a large amount of friction heat and revolution surface. In working process,the heat which comes from friction of worktable. with oil film as well as process ofsystem operation will transfer to worktable through contact surface betweenworktable and oil film. The heat will lead to large thermal deformation of worktableand then affect machining accuracy. So this paper makes simulation analysis oftemperature filed and thermal deformation field. Firstly, three-dimensional model ofworktable will be established by modeling software UG and reasonablesimplification will be made basing on actual operating conditions. Then, uniquenessconditions including convective heat transfer coefficient and initial boundaryconditions will be determined according to heat transfer theory as well as actualworking conditions. Finally, mesh generation and simulation analysis will be carriedon by Ansys Workbench software when uniqueness condition is applied to worktablele. After analyzing simulation results, trend of temperature distribution andthermal deformation field will be obtained at different rotating speed. Meanwhile, themethod increasing circumferential reinforcing plates is proposed to reduce thermaldeformation, and thermal deformation of the improved model will be analyzed toverify feasibility of this method.By the simulation analysis about physical field of hydrostatic bearing worktable.the distribution law of temperature and thermal deformation can be revealed andprovide theoretical basis for structural design of worktable. By analyzing theinfluence of reinforcing plate on thermal deformation field, the method increasingcircumferential reinforcing plate is proposed to reduce thermal deformation, whichalso improves machining precision and efficiency.