Based on the theory of thermal expansion deformation of metallic materials, extensional beam theory, non-uniform temperature distribution of the Euler-Bernoulli beam and Kirchhoff theory of plane-section assumption, a novel model was proposed to calculate the bending thermal deformation of lathe bed and upright column of double-column vertical NC gear hobbing machine.The research on the axial deformation and bending deformation of the upright column were also carried out by utilizing the deformation theory of the deformation element and equilibrium element Method. Compared the calculation results with the practical experimental values of the thermal deformation of the machine tool, it was shown that the relative error of the results was lower than 5%. The above analysis indicated the effectiveness and validity of the research method, which has great reference value and instructive significance for optimum structural design, cutting point position error prediction and compensation on double-column vertical NC gear hobbing machine.
