This paper describes the analysis, design, and testing of a low profile thrust bearing in a DR 990 industrial gas turbine. High unit loads and speeds, and the need to maintain low frictional power loss presented many challenges. The thrust pad design utilizes a flexure pivot, which allow near optimum performance for a wide range of speeds and loads in comparison to a fixed geometry taper land design. The use of high conductivity material for the thrust pads and directed lubrication allowed operation at lower temperatures. Finite element analysis was used to model the pad structure and pivot support. This analysis was confirmed by measuring the pad tilt using an eddy current probe. The test was conducted in a controlled thrust rig allowing accurate application and measurement of the thrust load. Precision manufacturing of the spherical seat and the application of a proprietary coating allowed better aligning capability under load. The bearing was tested in an engine at a range of speeds and loading conditions. The results are presented and compared with the existing fixed geometry bearing design. The bearing is currently running in an engine in the field and has accumulated 2,400 hours of operation with no forced outages.

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