Closed-circuit steam-cooled bucket with integrally cooled shroud for gas turbines and methods of steam-cooling the buckets and shrouds

摘要

The bucket 10 of a gas turbine includes first and second steam supply passageways 32 and 34 for directing cooling steam radially outwardly along the bucket. Steam return passageways 40, 42 and 44 lie adjacent the trailing edge for returning cooling steam to its source. A shroud is disposed at the bucket tip and has cross-over passages communicating the supply steam from the first and second passageways to the fifth, third and fourth passageways, respectively.