Abstract: The finite element analysis (FEA) model of a new type of heavy hybrid machine tool is built considering the stiffnesses of bearings and guideways. The deformation of the machine tool under the rated loads is computed. The static stiffnesses of the machine tool are derived and compared with the results of the static stiffness experiment. Due to the little difference between them, the simulation results are considered to be reliable. In order to improve the static stiffnesses of the ma-chine tool, the bearings with better stiffnesses are chosen and preloaded more than before. The simulation results indicate that the static stiffnesses of the machine tool become better after the optimization.

Key words: Bearing, Guideway, Hybrid machine tool, Static stiffness