Simulation And Experimental Research Of Fixed-state Parts In Centrifugal Disk Finishin

With the development of the manufacturing industry,the quality requirements for various components are gradually improved.In particular,the development of high-end equipment has led to higher and higher surface quality requirements for components to meet the performance and service requirements.Mass finishing technology not only improves the surface quality of parts but also improves its mechanical properties,and received the attention by experts and scholars from domestic and foreign.Various of mass finishing processes are applied to the final processing of many kinds of parts,effectively improving the surface properties of parts,reducing roughness,removing the machining marks.The centrifugal disk mass finishing process has the advantages of high processing force,high efficiency,also is convenient to construct automatic production line and add in flexible manufacturing system.However,because of wear and tear between the fixed cylinder wall and the rotary disk during the machining process,and friction of the workpiece during the machining process,the application of the centrifugal disk mass finishing process is less.Based on DEM(Discrete Element Method),this paper simulates the media particle motion to supplement the vacancies in research.At the same time,it proposes to fix the workpiece during processing which proposal draws on the spindle barrel finishing process.Exploring and analyzing the processing effect under different fixed positions and angles through the simulation,force test and processing test.Details as follows:(1)Using EDEM to simulation of media movement with different rotational speed and different media loads in the centrifugal disk finishing process.The influence of the rotational speed and the loading amount on the velocity distribution,the creep height and the radial distribution width of the spiral vortex motion of the media is analyzed,the movement of the media in the barrel is mainly divided into three areas: 1.the vortex area;2.the rotary disk area;3.the fixed cylinder wall area.The average speed of the media in the rotary disk area is the largest,about twice in the vortex area,the fixed cylinder wall area media speed is the lowest.Among them,the number of media in the vortex area accounts 60.73,the fixed cylinder wall area is second,and the rotary disk area is the least.The average speed of the media increases with the increase of the rotational speed of the rotary chassis,but the increase of the average speed tends to be gentle.The creep height increases with the increase of the rotational speed of the rotary chassis,showing a certain linear law,and the radial distribution width decreases as the rotational speed increases.(2)Using EDEM to simulate the centrifugal disk finishing process of different state workpiece.The comparison about the speed of media and the media force on the workpiece shows that in the fixed state process has a higher energy utilization rate than in the free state.The highest efficiency is obtained when the fixed angle ?=0° and ?=0°.When ?>0°,with the increase of the ? angle,the media force first decreases and then increases,and the increase of the normal contact force is greater than that of the tangential contact force,at ?=0° the contact force is the largest.Also the media force increase with the depth increase in different region of the workpiece.As the angle of ? increases,the contact force increases first and then decreases,but the difference between them is very small.At different ? angles,there is a surge in contact force in the bottommost area of the workpiece.The most obvious increase of the contact force occurred at 30°.(3)Measuring the force of the workpiece from media at different positions in the platen by dynamic force sensor.It is analyzed that the force is affected by the immersion depth and radial distance at the same speed,the deeper depth and the greater radial distance,the force is greater.The force varies more with depth,about 5.2 times of the radial distance,and the change with depth is consistent with the simulation results.Everywhere,the greater rotational speed,the greater force.As the depth increases,the trend of force changes with the speed increase is slow down.The radial distance only changes the force does not change its law with the rotation speed.(4)The interactive orthogonal experiment is designed to analyze the effect of fixed angle and rotary chassis speed on machining effect at the same position.The results show that the angle ? has the greatest influence,followed by the speed n and finally the angle ?,the effects of the ? angle and the ? angle are the same as the simulation results,the ? angle has a large interaction with the rotation speed n.The interaction between the ? angle and the other two factors can be neglected.Also,good finishing efficiency and finishing effect when n=135 r/min,?=0°,?=0°,and it is known that it is most reasonable and efficient when finishing 30~40min.