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 bands of the nozzle segments on a lower pressure side of the chordal hinge seals. To minimize or prevent leakage flow across the chordal hinge seals, a generally U-shaped supplemental seal having reversely folded U-shaped marginal portions is received in a cavity formed in the axially extending sealing surface of the inner rail of the nozzle segment. At operating conditions, the marginal portions seal against the base of the cavity and the annular sealing surface of the nozzle support ring to prevent leakage flow past the chordal hinge seal from entering the hot gas path. To install the supplemental seal, the seal is first compressed and maintained in a compressed state by applying one or more wraps about the supplemental seal or an epoxy to secure the seal when compressed in the cavity. At operating temperatures, the retention means releases the seal to engage marginal portions against opposite sealing surfaces of the nozzle segment and support ring.

Supplemental seal for the chordal hinge seals in a gas turbine

A turbine shroud apparatus is provided for a gas turbine engine having a central axis. The apparatus includes: (a) an annular support member (14); (b) a turbine shroud (12) disposed in the support member (14), the shroud (12) being a continuous ring comprising a low-ductility material and having opposed flowpath and back surfaces, and opposed forward and aft ends; and (c) a spring (32) mounted between the support member (14) and the shroud (12) and arranged to resiliently urge the shroud (12) to a concentric position within the support member (14).

Mounting apparatus for low-ductility turbine shroud

A turbine ring assembly includes a ring support structure and a plurality of ring sectors, each including a single piece of ceramic matrix composite material. Each ring sector includes a first portion forming an annular base with an inside face defining an inside face of the turbine ring and an outside face from which there extends two tab-forming portions including ends that are engaged in housings in the ring support structure. The ring sectors present a section that is substantially π-shaped and the ends of the tabs are held without radial clearance by the ring support structure. The tabs can have a free length in meridian section that is not less than three times their mean width.

Turbine ring assembly

A seal housing is provided to substantially cover at least one duct wall of vane array duct of a gas turbine engine, and one example arrangement is employed in a mid-turbine frame. The arrangement provides improved sealing of the vane array duct through the provision of a plurality of cavities extending along the duct wall. The arrangement may also include insulation tubes to assist in sealing around load transfer spokes passing through the vane array.

Sealing for vane segments

A turbine inner shroud and a turbine assembly. The turbine assembly includes a turbine stator having a longitudinal axis and having an outer shroud block with opposing and longitudinally outward facing first and second sides having open slots. A ceramic inner shroud has longitudinally inward facing hook portions which can longitudinally and radially surround a portion of the sides of the outer shroud block. In one attachment, the hook portions are engageable with, and are positioned within, the open slots.

Turbine inner shroud and turbine assembly containing such inner shroud

A seal assembly for a turbine blade tip shroud including a one-piece bent metallic sheet inter-segment seal having an axial component and a vertical component adapted to fit in a groove formed in the end walls of each shroud segment, wherein the shroud segment has a plateform and radially extending ribs, and the seal fits tightly in the groove providing an axial an a radial component to the seal. A ring seal is also provided for sealing a joint between the shroud and a mounting structure where an annular gap is formed having an "L" shaped cross section, the ring seal having a "C" shaped configuration and one of the legs of the "C" extending within an axial component of the "L" shaped gap. The leg has a wave pattern with the peaks of the wave in contact with opposite radial walls of the axial component of the gap for creating a gas seal at the joint.

James Christopher Crone

Papers

Gas turbine engine shroud seals