Tilting-pad journal bearings are widely used in industry to support rotating shafts due to their high dynamic performance. The operating limits of these bearings are mainly represented by the maximum permissible temperature of the lined materials of the pads and by the minimum thickness of the oil-film under which mixed lubrication can occur. The current trend in bearing development sees the adoption of innovative materials in the production of the pads, that provide higher load capacity, higher temperature capability and greater fatigue resistance. In this paper, the static characteristics of bearings lined with different materials, will be investigated. The temperature distribution in the bearing will be evaluated by means of a full 3D thermal model whereas the deformation of the pads will be evaluated by means of a finite element model. At the end, the permissible operating range in terms of load and speed will be defined for each material by considering the limits on the maximum temperature, permissible mechanical stress and minimum oil-film thickness.
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