Moisture removal grooves on steam turbine buckets and covers and methods of manufacture

摘要

Covers on bucket tips are provided with an access slot along a circumferentially facing edge of the cover at a location where moisture removal grooves of the bucket will intersect with the cover. Machine tooling is then applied to form the grooves along the suction side and adjacent the leading of the bucket. The machining runs out through the access slot forming grooves along the side edge of the bucket cover within the slot. The axial extent of the covers overlying leading and trailing edges of the buckets is maintained while enabling moisture removal by centrifugal action.