Prediction model of the clearance oil film for static vertical rail considering the ram deformation

In order to improve the cutting rigidity of hydrostatic oil pad on large vertical lathes' vertical rail of hydrostatic ram, on the basis of a single-chamber oil pad, this paper proposed a new type of the double-chamber oil pad. Pressure field distribution law of the single-chamber and the double-chamber oil pad was obtained by the finite element volume method. Then, using the fluid-structure coupling method and Workbench software the deformation law of ram was obtained under different working conditions. Finally, oil film's prediction model of the single-chamber and the double-chamber oil pad was solved under different working conditions. Oil film's prediction model of the single-chamber oil pad and the double-chamber oil pad was obtained under various working conditions. The results show that the maximum deformation of the single-chamber of upper oil pad ranges from 0.079 to 0.92 mu m, while the double-chamber oil pad ranges from 0.07 to 0.68 mu m. The maximum deformation of the single chamber of lower oil pad ranges from 0.91 to 9.21 mu m, while the double-chamber oil pad ranges from 0.74 to 9.14 mu m, and the maximum deformation of the double-chamber oil pad is less than that of the single chamber, which shows that the rigidity of the double-chamber oil pad is better than that of the single chamber. The results are helpful to improve the bearing performance and service life of bearings.