Thermo-mechanical modeling of high speed spindles

Prediction of the thermo-mechanical behavior of machine-tool spindles is essential in thereliable operation of high speed machine tools. in particular, the performance of these high speedspindles is dependent on their thermal behavior. the main source of heat generation in the spindle is thefriction torque in angular contact ball bearings. this paper presents an effort to develop a comprehensivemodel of high speed spindles that includes viable models for the mechanical and thermal behaviorof its major components, i.e., bearings, shaft and housing. spindle housing and shaft are treated assix-degree-of-freedom timoshenko beam elements. bearings are modeled as two-node elements with fivedisplacements and a thermal load component at each node. mutual interaction between the thermal andstructural behavior of both spindle shaft/housing and bearings is characterized through thermal expansionand the rate of heat generation/transfer. components are combined to form a finite element model for thethermo-mechanical analysis of spindle-bearing systems.the results of simulation for a typical spindle system are presented.