Stiffness Analysis And Hydrostatic Spindle Design Of Hard Turning Machine

Hard turning is a technique for turning high-hardness materials.Hard turning technology,as a new type of processing technology that can replace grinding processing by turning processing,has attracted more and more people's attention in current manufacturing.The previous turning machine tools could not directly cut high-hardness and high-strength materials.At the same time,the grinding process itself has the disadvantages of low processing efficiency and high manufacturing cost.Therefore,the hard turning technology relies on its high processing efficiency,low pollution,and processed workpieces.Many advantages such as high precision have good application prospects in the fields of automobile,aerospace,instrument,bearing manufacturing and so on.However,there is currently no widely used hard cutting machine tool in China,and there is a big gap between the research and development of hard turning machine tool characteristics and developed countries.At the same time,domestic research on the rigidity and load-bearing characteristics of hydrostatic bearings is also insufficient.This subject takes the overall stiffness of hard steel turning machine tools and the hydrostatic spindle as the main research objects,and the purpose is to provide experience and reference for the stiffness distribution of hard turning machine tools and the stiffness optimization design of hydrostatic bearings.This article first designs the structure of the hard turning machine tool from the perspective of high rigidity and high processing efficiency of the hard cutting machine tool,and analyzes the cutting force variation range during hard turning through the finite element simulation method.At the same time,it analyzes the hard turning machine based on the technical indicators of the hard turning machine tool.The stiffness of the machine tool is modeled on the stiffness of the machine tool,and the influence of the stiffness of its main components on the stiffness characteristics of the machine tool is analyzed,and the stiffness design and distribution of the main components of the machine tool are realized on this basis.The key part of the hard turning machine tool is the spindle.Compared with other bearing forms,the hydrostatic spindle's high rigidity,high shock resistance,and high precision make it possible to turn hard steel materials.Under the assigned stiffness parameters,this paper uses the classical numerical calculation method to design the structure of the hydrostatic spindle,and then uses the finite element analysis method to analyze the static and dynamic characteristics of the hydrostatic bearing of the machine tool.At the same time,it uses the fluid-solid coupling Methods The deformation of hydrostatic bearings under different hydraulic oil pressures was studied,and the structural parameters and hydraulic oil parameters of the hydrostatic bearings were optimized to meet the requirements of high rigidity hydrostatic bearings required by hard turning machine tools.Finally,through the method of hydrostatic bearing static characteristics experiment,the flow field,load bearing and stiffness of hydrostatic bearing are tested and analyzed,and the stiffness of the hydrostatic bearing used in the experiment is optimized,and the different structural parameters obtained by finite element simulation are verified at the same time.Under the changing law of load and stiffness of the hydrostatic bearing,the structural parameters of the optimized hydrostatic bearing are given.