Abstract
Many studies reported that the membrane restrictor may have excellent performance when it was properly designed. However designs of membrane restrictors are much complicated than other frequently used restrictors i.e. capillary restrictor and orifice restrictor for hydrostatic bearings. General rules of membrane restrictor designs, which can be readily available for use by industry designers and engineers are needed. In this study, it is examined that a high static stiffness of the bearing is attainable as two design parameters of membrane-type restrictor are properly chosen. The first one is the dimensionless stiffness of the membrane (Kr*) and the other one is the design restriction ratio of the bearing system (λ). When the deformation-load relationship of the restrictor is compliance with the ideal trend, the stiffness of the bearing should theoretically approach infinite in most application range. It was derived that Kr* = 1.33 and λ = 0.25 is the solution for such condition. The film thickness for the bearing will be maintained at designed levels over a loading range. The optimum result is applicable not only for single-pad bearing but also for opposed-pad case. The recommended value for obtaining the great stiffness of an opposed-pad bearing is Kr* = 1.33 and λ = 0.13~0.24. In the case where the upper pad and lower pad are equally designed, the displacement of the bearing can be maintained less than 6 percent of a non-loading clearance if the recess pressure extending to 73 percent of the supply pressure.