Abstract: A bearing, a gas turbine unit having such a bearing, and a method for operating and for increasing the efficiency a gas turbine unit, wherein the bearing has an annular bearing body, on the axially opposing end faces of which are provided two thrust bearings, each having a plurality of bearing elements which are distributed over the circumference, project and are movable in the axial direction, and have a bearing surface. The bearing elements of each thrust bearing are hydraulically displaceable axially outwards in two stages by predetermined amounts of movement.

Abstract: A method for modifying an existing single shaft combined cycle power plant having a steam turbine part and a gas turbine part which are connected to each other rigidly by an intermediate shaft. The gas turbine part is supported by two pin-ended supports allowing a certain axial displacement of the casing by rotating about corresponding axes. The old gas turbine part is replaced by a new gas turbine part having a different structure, namely a rigid support and a flexible support. Relative thermal expansion or displacement of the intermediate shaft is compensated by a hydraulic unit comprising a double-acting piston for displacing the gas turbine rotor with respect to the gas turbine stator. The hydraulic unit is controlled based on a displacement measurement in the steam turbine.