The influence of design parameters on the static performance of a newly designed self-compensating hydrostatic rotary bearing was investigated. The bearing was designed by incorporating the main attributes of angled-surface self-compensating bearing and opposed-pad self-compensating bearing. A governing model based on flow conservation was built to theoretically study the static performance, and the methodology was validated by experiments. It is pointed out that the influence factors on the bearing static performance are the designed resistance ratio of the restricting land to the bearing land, the inner resistance ratio of the land between pockets to that between the pocket and the drain groove, the initial clearance ratio of the restricting gap to the bearing gap, and the semiconical angle. Their effects on the load carrying capacity and stiffness were investigated by simulation. Results show that the optimum designed resistance ratio is 1; the initial clearance ratio should be small, and the inner resistance ratio should be large. 1. Introduction Hydrostatic bearings are widely used in high precision mechanisms and machines for the advantage of low friction, high stiffness, high accuracy, and long life. The pressure in the hydrostatic bearings is generated by external pumps, and compensation devices are necessary to regulate flow into the pockets. Garg et al. [1] presented a review on the design and development of hybrid/hydrostatic bearings, in which researches on the compensation devices are reviewed. Martin [2] summarized the operational principle of constant-flow and constant pressure restrictors. Malanoski and Loeb [3] theoretically investigated the compensation effects of capillary, orifice, and constant-flow restrictor on the static stiffness of hydrostatic thrust bearing. Sharma et al. [4] studied the slot-entry hydrostatic/hybrid journal bearing using finite element method and revealed that asymmetric slot-entry journal bearings provide an improved stability threshold speed margin compared with asymmetric hole-entry journal bearings compensated by capillary, orifice, and constant-flow valve restrictors. Singh et al. [5] studied the performance of membrane compensated multirecess hydrostatic/hybrid journal bearing and found that selection of recess shape along with a suitable compensation device is needed to get an improved performance of the bearing. Kumar et al. [6] investigated the restrictor design parameter of capillary compensated journal bearings. Gao et al. [7, 8] analyzed the static and dynamic characteristics of hydrostatic guides
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