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The Hydrostatic Bearing System (HBS) is one of the core assemblies of the Giant Magellan Telescope mount. It supports the high dead loads of the moving parts of the entire telescope while providing a stick slip free rotation in the main axes. It is capable of compensating for structural deformations while maintaining a thin oil film layer between the moving parts. Hydraulic groups have been designed to provide the kinematic compliance required to keep the bearing loads almost constant, even under geometrical deviations. The complete development of the bearing was supported by Finite Element Analysis (FEA) for various aspects. FEA was used to predict the deformation of the bearings and tracks under hydraulic loading down to the micrometer level in order to verify one of the major contributors to the oil film budget. On the other hand, FEA was taken to perform quasi static deformation analyses of the entire telescope for gravity load cases and verify alignment of optical elements and provide the basis for the levelling and tilting feature sizing of the HBS. Furthermore, a comprehensive seismic analysis was performed with various loads. The results were a driver for the hydraulic schematic. In addition to the FEA, a dynamic simulation was carried out to analyze the dynamic effects of wind loads and the effects of load variations when bearing pads pass geometrical deviations of the tracks. In the end, a good balance was found between stiffness and limited disturbances. Careful leakage analyses were performes and taken into account in the design optimization to minimize the risk of oil contamination. This was achieved by a combination of oil suction, active scrapers, seals and by guiding measures to lead back the remaining oil to the main oil return system.
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