SEALING DEVICE FOR GAS TURBINE STATOR BLADES

摘要

A sealing device for a gas turbine stator blade, in which a sealing pressure of an inner shroud is raised to enhance a sealing effect. An outer shroud 32 is mounted through heat insulating rings 32a and 32b on a blade ring 50, and this blade ring 50 has air holes 1 and 51, of which the air hole 1 communicates with a space 53 whereas the air hole 51 communicates with a seal tube 2. This seal tube 2 is inserted at its leading end portion 3 into the air hole 51, and a spring 6 is arranged between a projection 4 of the tube 2 and a retaining portion 5 of the air hole 51 to fix the seal tube 2 removably. Cooling air 54 flows on one side from the air hole 1 into the space 53 to cool the shrouds and the inside of a stator blade 31 until it is released from the trailing edge, and on the other hand into a cavity 36 so that the inside of the cavity 36 is kept at a high pressure without receiving a pressure loss because the tube 2 is independent of the space 53. The high pressure air from the cavity 36 flows out from seal portions 40a and 40b, as indicated by arrows S1 and S2, to prevent the inflow of the hot gas from a combustion gas passage.