This study presents the experimental results of the effect of pump pressures and loads on the stiffness of the spindle integrated a new designed and fabricated hydrostatic bearing. The experiment results show that, with a known oil viscosity of PaS, a pump pressure of 5 MPa and a load in a range 500 – 1000 N are the most feasible working condition of the medium – sized external circular grinding machine 3K12 |