Supplemental seal for the chordal hinge seals in a gas turbine

摘要

In a gas turbine having a chordal hinge seal between an inner rail of each nozzle segment and an annular axially facing sealing surface of a nozzle support ring, a supplemental seal is disposed between the support ring and inner band of the nozzle segment on a high pressure side of the chordal hinge seal. The supplemental seal includes a pair of sheet metal shims overlaid by a woven metallic cloth supported by a bracket secured to the inner margin of the inner rail. The radially inner end of the cloth seal bears against the annular sealing surface of the nozzle support ring. The shims of the legs of the supplemental seal are slit along their distal margin and staggered circumferentially relative to one another to provide flexibility and effective sealing engagement with the nozzle support ring.