Analysis Of Upper Interface Change And Machining Uniformity Of Abrasive In Spindle Barrel Finishing

With the progressive increase of high-tech requirements for the surface quality of precision parts,the barrel finishing technology for the purpose of improving the surface quality of the parts is gradually progressing towards informatization and digitization.Spindle barrel finishing has been widely used as a kind of barrel finishing technology.This technology is suitable for the finishing of large and medium-sized discs and shaft parts.In order to fill the research gap of the geometric shape change of abrasive interface in the spindle barrel finishing process and to solve the problem of non-uniform axial machining of the workpiece,based on the discrete element method,this paper mainly studies from the following four aspects:(1)Abrasive can be thrown out of the barrel at high speed in Spindle Barrel Finishing.To determine the maximum filling height of the barrel,simulation of Spindle Barrel Finishing by discrete element method,geometry characterization of abrasive upper interface using curve fitting,the orthogonal simulation analyzed main influence factors of the geometric shape.Single factor simulation explored the effects of barrel speed and the verification experiment was carried.The abrasive upper interface is paraboloid.Barrel speed and abrasive shape have a crucial effect on the paraboloidal geometry.Paraboloids approximately concurrent one circle at the filling height of abrasive in different barrel speed.The circle radius is 5/7 of the barrel radius.Maximum filling height of the barrel can be calculated under certain barrel speed.(2)In order to understand the influence of the contact force of the abrasive particles on the material removal rate of the stainless steel workpiece,the material removal rates on the axially short workpiece with different processing angles and the axially long workpiece at different positions were analyzed experimentally and the contact forces of the abrasive particles were analyzed numerically.The experimental results were compared with the simulation results.The results show,for 201 stainless steel workpiece,that the material removal rates of axially short workpieces with different machining angles are mainly affected by the contact tangential forces of abrasive particles.The larger the contact tangential force,the greater the material removal rate.The maximum contact tangential force at a processing angle of 45°.The material removal rates at different positions on the axially long workpiece are mainly affected by the contact normal forces of abrasive particles.The larger the contact normal force,the greater the material removal rate.The deeper the position in abrasive,the larger the contact normal force.(3)In view of the uneven machining of workpieces in the axial direction,in order to understand the distribution of the contact normal forces between abrasive particles and the workpiece,the contact normal forces at different positions of the stainless steel workpiece and the contact normal forces on the workpiece of different positions and the contact normal forces ideally were respectively simulated and analyzed.The removal of materials at different positions of the stainless steel workpiece and the material removals of workpieces at different positions were respectively verified experimentally.The results show that the contact normal forces at different positions of the vertical workpiece logarithmically decrease with the increase of the distance from the bottom of the barrel.Vertically,the contact normal forces on the workpiece of different positions decrease with the increase of the distance from the bottom of the barrel in the form of a quadratic function.Horizontally,the contact normal forces increase with the increase of the distance from the central axis of the barrel in the form of an upward quadratic function.(4)In order to solve the problem of non-uniform axial machining of workpieces,the feasibility of workpiece tilt processing was analyzed,and the processing uniformity of stainless steel workpiece tilt processing was analyzed and verified.The results show that when the workpiece is placed between the two places with the same contact normal force,the force is more even in the axial position of the workpiece.