Sealing device for the cool steam eadership in a gas turbine

摘要

PROBLEM TO BE SOLVED: To solve a problem, in a sealing structure for a stream passage between a stationary blade and a blade ring of a gas turbine capable of preventing leakage of cooling stream in the stationary blade and the blade ring, that a conventional structure has not absorbed deformation caused by the heating of the stationary blade and the blade ring, so that occurrence of a micro gap occurs has caused a trouble due to cooling steam leakage.;SOLUTION: This sealing structure for stream passage between the stationary blade and the blade ring is formed with a steam passage in the blade ring, a stepped part at a steam shielding-connecting part communicating the steam passage chamber with cooling steam feeding piping on the stationary blade side, and a stepped part at a the cooling steam feeding pipe of the stationary blade opposing the steam shielding-connecting part, respectively. Hollow and cylindrically-shaped seal piping inserted into the steam shielding-connecting part joints it to the cooling steam feeding pipe of the stationary blade and respective stepped parts are held and fixed by a seal-press guiding apparatus. As a result, even if the stationary blade and the blade ring are thermally deformed, the cooling steam feeding pipe or the like expands and contracts axially, so that thermal deformation can be absorbed, steam leakage attributed to occurrence of a micro gap can be prevented, and a drop in combustion gas temperature can be prevented which is caused by enhanced driving force of a steam turbine attributed to recovered steam and an inflow of leaked steam into combustion gas. It is thus possible to improve driving force, thereby enhancing thermal efficiency in a power generating plant or the like.;COPYRIGHT: (C)2002,JPO