Patent ID: 9133711
Filing Date: 2015-09-15
Classification: F01D,F02C,F05D

Abstract:
1. A steam turbine, comprising: an outer casing; an inner casing provided inside the outer casing; a nozzle box having a circular ring-shaped steam passage into which steam is led from a steam inlet pipe and having, on a downstream portion of the steam passage, a plurality of first-stage nozzles in a circumferential direction, the steam passage being provided inside the inner casing, the first-stage nozzles being welded directly to the downstream portion of the steam passage; a second-stage nozzle side structure in a cylindrical shape being separable from and combined with the nozzle box and having a plurality of second-stage nozzles in a circumferential direction, the second-stage nozzle side structure having a fitting portion on an outer surface thereof fitted to the inner casing; at least a pair of abutment surfaces abutting each other and configured to seal, the surfaces being respectively provided in the nozzle box and the second-stage nozzle side structure, without being parallel to a turbine rotor axis; and a seal member provided in a part of a gap between the nozzle box and the second-stage nozzle side structure, the gap being formed by combining the nozzle box and the second-stage nozzle side structure.