SHAFT SEAL AND TURBINE USING THE SHAFT SEAL

摘要

A shaft seal excellent in wear resistance which reduces the amount of gas leakage from a high pressure side to a low pressure side, wherein flexible thin sheets (18) are laminated in ring-shape and disposed mainly around a rotating shaft (11) of a gas turbine, the turbine comprises a casing (12), a compressor, a rotating shaft (11), rotor vanes installed on the rotating shaft (11), and stator vanes installed in the casing (12) so that they are opposed to the rotor vanes, and the shaft seal is disposed between the plurality of stator vanes and the rotating shaft (11) so that each thin sheet (18) is brought into contact with the rotating shaft (11), whereby, during the rated operation, the tips of the thin sheets (18) are floated slightly from the surface of the rotating shaft (11) by a dynamic pressure caused by the rotation of the rotating shaft (11) and, when the operation is stopped, the tips of the thin sheets touch the rotating shaft (11) again by an elastic restoring force of the thin sheets (18).