A test rig to study the performance of water-lubricated high-speed hybrid bearings

A new high-speed and high-precision spindle system test rig has been developed for evaluating the performance of water-lubricated high-speed hybrid bearings. The hybrid bearing is consisted of four stepped recesses and two symmetric circumferential grooves. The orifice compensated hybrid bearings have been successfully used in a high-speed spindle system. The rotating speeds of the spindle system test rig range from 6,000 rpm to 30,000 rpm, which makes it possible to simulate many actual machining processes. Initial experiment has been presented to study the mechanical and thermal behaviours of the rotor-bearing system. The obtained results indicate that the temperature rise at a maximum speed up to 30,000 rpm is less than 15°C at 2.5 Mpa supply pressure, and the racial run-out tolerance is about 1μm. The test rig can be used to investigate the performance characteristics in static and dynamic conditions, especially for high rotating speeds.