Theoretical Analysis And Numerical Simulation Of Cutting Heat In The High Speed Precision Milling Process Of Scroll Plate

Scroll compressor is one of the rapid and efficient volumetric fluid machines,its characteristic of scroll plate of core components have been studied more and more deeply.In the process of high speed cutting machining,the generation of the thermal deformation is the main reason the affects the precision and quality of the scroll plate,and it is unfavorable factor of the decrease of tool hardness,the shortening the life of tool and increasing the machining costs.This paper mainly focuses on the cutting heat problem during the high speed precise milling process of the combined scroll plate.This main work is as follows:1.NC milling machine of scroll plate of combined profile.Scroll plate is machined by the method of numerical approximation,the rough machining strategy is adopted first,and based on the rough machining,by the way of precision milling,we can obtain the geometric size,shape precision and surface quality to meet the requirements of workpiece.2.Analysis of temperature changes at any time and position.By the method of a single variable,the y value is certain,x=z=20mm,the variation of temperature caused by different heat with time is simulated,increased firstly and then decreased,the temperature reaches tha maximum value at 20 s,at this time,the temperature difference is 208?,it gradually decreases to zero with time;the temperature changes with time are analyzed at 20 s under different z value,basically temperature tends to room temperature at the x=0.06 m position.3.The theoretical analysis and numerical calculation of three deformation areas.The cutting heat between tool and scroll plate mainly comes from the shear area and tool-workpiece friction area.The effect of heat generated by two deformation is studied.The heat ratio distribution coefficient R1 in the shear area and the heat transfer coefficient R3 of the friction area increase with the increase of the spindle speed.Therefore,the higher the spindle speed,the less heat is transferred to the workpiece.4.The change law of shear temperature and strain-stress and the change of temperature with time in the actual milling process.With the increase of cutting speed v,shear strain rate increases by 213/s,the shear stress increase approximately20 MPa,temperature has been an upward trend when the speed reaches 7000r/min,at this time,the temperature of scroll plate rises slowly,cutting temperature keeps atabout 754?.In the actual milling machine,the temperature remain a stable value of103? at low speed,but the initial temperature has reached 570? at high speed,the temperature value tends to be about 750?.Through the process of high speed precision milling of scroll plate,the study of cutting heat problem of high speed precision milling is compared with actual milling machine with good consistency,which can reduce the scroll plate temperature rise,reducing the heat deformation,has a guiding significance to improve the machining quality and precision,and provides a reference value for the further research of cutting problem of variable section scroll profiles in the process of high speed precision milling.