Asymmetric Supply Type Hydrostatic Journal Gas Bearings to Support Large Load Rotors

Rotating machinerys have problems at bearings to support a rotor such as seismic ACROSS transmitters. The ACROSS ( Accurately Controlled Routinely Operated Signal System ) is a new technical method to detect subtle changes in the physical state of Earth's structure using precise and continuous signal transmitter-receiver systems. The signal is a type of sinusoidal elastic waves, which is generated by a large unbalanced rotor. The rotor is supported by rolling contact bearings. The bearings in the transmitters, large heat generation occur caused by the high frictional loss. In order to solve this problem, use of hydrostatic gas bearings was studied. Effectiveness of the gas bearings was clarified by the test for decrease of frictional loss. However, large gas flow rate was required to support large load. In this paper, asymmetric supply type hydrostatic journal gas bearing is developed to support large load with decreasing of gas flow rate. Numerical calculation of the bearing characteristics is conducted and the results are compared with previously studied and conventional bearing. The test bearing and a rig were made and the test was conducted. Availability of the bearing is verified by the test.