Thermal Characteristics Analysis For Cylindrical Grinder Of Railway Bearing Ring

The cylindrical grinder of railway bearing ring is a precise grinding equipment for inner ring raceway and the major diameter,its thermal properties directly affect surface quality of railway bearing ring.Therefore,it is of great significance to conduct thermal characteristics analysis for cylindrical grinder of railway bearing ring.Thermal characteristics research and thermal design of the 3MK2125 cylindrical grinder of railway bearing ring was conducted.And contents completed in this paper are as follows:(1)The 3D digital model and thermal model of the 3MK2125 cylindrical grinder of railway bearing ring are established.The energy flow model of bearing-ring grinder is established to revel energy transfer paths and dissipating ways of grinder.(2)The formula of the friction power loss for the tilting pad bearing and thrust bearing has been derived based on Newton's law of viscosity;and the thermodynamic equilibrium equation for the spindle lubrication system has been established according to on energy conservation law.(3)Modeling methods for heat sources of grinding spindle system with tilting pad bearing and workpiece spindle system have been studied;thermal boundary conditions have been obtained by using the heat transfer theory;thermal model of the spindle systems have been built to calculate their temperature distribution and thermal displacement distribution by aid of the finite element method;the influence of related factors on the thermal characteristics of spindle systems have been discussed systematically.(4)The influence of main factors such as the grinding spindle system with tilting pad bearing,workpiece spindle system,the cutting fluid and the slide way oil on the thermal characteristics of grinder has been studied,and the grinding errors of the cylindrical grinder under single action of factors above are calculated;the thermal characteristics of the cylindrical grinder under actual operating conditions has been figured out.and the effect of thermal deformation of grinder on grinding errors is also calculated;experiments are finally conducted to verify the proposed thermal model for the grinding spindle system with the tilting pad bearing.(5)Effects of lubricant flow rate,temperature of cutting fluid and slid way oil,and support form of grinding spindle on thermodynamic performance of the cylindrical grinder have been discussed systematically,and thermal design of the grinder is completed.Research results are as follows:The thermal analysis method for the grinding spindle system with tilting pad bearing,using Newton's law of viscosity and the principle of thermal equilibrium,has been verified by the test study;the grinding spindle system and the cutting fluid are the main factors that affect the machining precision of 3MK2125 cylindrical grinder of railway bearing ring;when the lubricant flow rate and the temperature of cutting fluid are both increased,and the angular contact ball bearings adopt higher viscosity grease,the axial grinding error of the grinder is reduced to 80.79?m,a drop of 32.88%;the thermal error of grinding wheel dresser is reduced to 85.83?m,a drop of 29.86%.