STEAM TRANSFER ARRANGEMENT FOR TURBINE BUCKET COOLING

摘要

STEAM TRANSFER ARRANGEMENT FOR TURBINE BUCKET COOLING The steam transfer arrangement includes dovetail connections between a turbine bucket 14 and a rotor wheel 12 wherein a steam supply passage 20 in the rotor wheel registers with a steam cooling passageway 28 in the bucket and a steam return passageway 30 in the bucket lies in registry with a steam return passage in the wheel. At the interface of the dovetail connection, each registering passage and passageway includes a sleeve 50, 52 disposed in an enlarged recess 54, 56, the sleeves having annular spherical sealing surfaces for engagement with annular spherical seats on the turbine bucket. The sleeves are compressible radially relative to the bucket to enable the bucket to be secured to the wheel and expand radially outwardly to ensure sealing fit between the sealing surfaces and seats.