The Critical Speeds of a Machine Tool Spindle- Bearing System with the High Stiffness Hydrostatic Journal Bearings
نویسندگان
چکیده
INTRODUCTION The ordinary hydrodynamic bearings have been replaced by the hydrostatic bearings in the application of machine tools in recent years. For the hydrodynamic bearings, the journal and the bearing surface are separated by the sliding action with a wedge pressure-generating mechanism to develop a pressure within the bearing. It has advantages of simple structure and cheap cost. However, the fluid film lubrication may break down if the system is at the low rotating speed, or during the startup and shutdown processes.
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