Simulation, Experiment, and Optimization Method for Thermal Characteristics of Machine Tool

The thermal characteristic of a spindle system is simulated by the finite element method. Temperature field and thermal deformation of the spindle system were simulated considering the establishment method of an entity model as well as boundary conditions of a finite element model, such as heat source, heat transfer coefficient, and thermal contact resistance between joints. Effects of the spindle system on thermal characteristics of the whole machine were discussed. Accuracy of the simulation was verified and compared with test results. The study shows that the key areas of temperature rise are located at the spindle bearing and spindle motor; thermal deformations of Y and Z directions are large; thermal characteristics of the spindle system have little influence on other parts. Thermal characteristics of the spindle system were optimized by changing the structures and sizes of the cooling passage located at the spindle box, and effectiveness of the optimization was verified by finite element simulation. The research results provide guidance for thermal characteristic simulation and optimization of machining centers.