A turbine shroud is formed by a ring of butted shroud segments. Each turbine shroud segment has a radially inwardly projecting annular flange which is seated on a radially outwardly facing surface of an annular tip of the outer shroud of the downstream nozzle stage. This flange is free to slide axially relative to the annular tip during thermal expansion of the nozzle outer shroud in the axial direction. Each turbine shroud segment has a spring seated thereon which urges the radially inwardly projecting flange toward the annular tip of the nozzle outer shroud. Honeycomb material attached to the turbine shroud segment discourages the flow of hot gases through the gap betwen the flange and annular tip of the outer shroud of the downstream nozzle stage attributable to seam chording, thereby reducing the leakage of hot gas into the spaces between the shrouds and the outer casing.

Low-pressure turbine shroud

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 includes a plurality of inner shell sections mounting first and second stage nozzle and shroud portions. The inner shell sections are pinned to an outer containment shell formed of sections to preclude circumferential movement of the inner shell relative to the outer shell and enable thermal expansion and contraction of the inner shell relative to the outer shell. Positive bucket tip clearance control is afforded by passing a thermal medium about the inner shell in heat transfer relation with the shrouds about the first and second stage bucket tips, the thermal medium being provided from a source of heating/cooling fluid independent of the turbine. Access is provided to the rotor and turbine buckets by removing the outer and inner shell sections.

Removable inner turbine shell with bucket tip clearance control

A shroud assembly for a turbine portion of a gas turbine engine, the shroud assembly comprising an annular ceramic shroud ring, a plurality of arcuate shroud support segments, and a plurality of inwardly biased resilient members The annular ceramic shroud ring is circumferentially disposed about radially extending blades of a turbine rotor and partially defines an annular hot gas passage of the turbine portion The plurality of arcuate shroud support segments are radially disposed outwardly of the ceramic shroud ring and are contiguous therewith The plurality of inwardly biased resilient members are each engaged between one of the shroud support segments and an outer annular turbine support case composed of a material having a different thermal expansion coefficient than the ceramic shroud ring The resilient members maintain contact between the shroud support segments and the ceramic shroud ring The shroud supporting segments and the resilient members are adapted to deflect to compensate for relative thermal growth differences between the ceramic shroud ring and the turbine support case

Attachment of a ceramic shroud in a metal housing

An electrical assembly for use in various operating environments such as a casing of a combustion turbine 10 is provided. The assembly may include an electrical energy-harvesting device 51 disposed in a component within the casing of the turbine to convert a form of energy present within the casing to electrical energy. The harvesting device is configured to generate sufficient electrical power for powering one or more electrical devices therein without assistance from an external power source. One example of electrical devices wholly powered by the energy harvesting device may be a sensor 50 connected for sensing a condition of the component within the casing during operation of the combustion turbine. Another example of electrical devices wholly powered by the energy harvesting device may be a transmitter in communication with the sensor for wirelessly transmitting the data signal outside the casing.

Electrical assembly for monitoring conditions in a combustion turbine operating environment

A high temperature turbine shroud assembly for an aircraft gas turbine engine comprising a plurality of arcuate ceramic blocks arranged in a ring. The blocks are supported by a pair of annular support members which retain the blocks in the assembly. Spring-like fingers associated with the support members apply a preloaded force against a pair of slanted dovetail surfaces on the blocks to force the blocks against rigid stops formed upon the annular support members, thereby establishing their proper radial position within the assembly. The preload applied by the fingers accommodates the thermal expansion differences between the ceramic blocks and the metallic support members. In an alternative embodiment, the blocks are retained between cooperating rigid legs extending from the annular support members and wedged radially inwardly into position by a preloaded spring contacting the back side of the blocks. Heat transfer between the blocks and metallic support members is minimized by providing point or line contact between components, thus reducing the contact area available for heat conduction.

Ceramic turbine shroud assembly

A clearance control apparatus has a positioning mechanism for controlling clearance between rotor blade tips and a shroud segment of a gas turbine engine casing, and a rotatable lever for actuating the mechanism. The positioning mechanism is supported by a casing boss, coupled to the shroud segment, and actuatable for moving the shroud segment toward and away from the rotor blade tips to reach a position at which a desired clearance is established. The mechanism includes a shaft and a pair of cam elements. The shaft is mounted by the boss for radial movement toward and away from the rotor axis and coupled at its inner end to the shroud segment. An outer cam element is attached to the outer end of the shaft and spaced outwardly from the boss. An inner cam element is attached to an end of the lever mounted to the boss for rotational movement about a longitudinal axis of the shaft. The inner cam element is located between an outer end of the boss and the outer cam element and engaged with the outer cam element such that rotation of the inner cam element with rotation of the lever produces radial movement of the outer cam element and of the shaft and shroud segment therewith toward and away from the rotor blade tips.

Blade tip clearance control apparatus using cam-actuated shroud segment positioning mechanism

Structure de virole comportant une virole en ceramique. Elle comprend des blocs en ceramique 40 disposes en anneau qui ont, vus en plan, une forme rectangulaire, ont une surface interieure arquee 42 qui delimite une partie du passage 38 d'ecoulement des gaz chauds et sont munis sur leurs cotes amont et aval de surfaces en queue d'aronde 44, 46 obliques par rapport a la face 42, les blocs etant maintenus en position par des organes de support annulaires 54, 56 qui appliquent aux blocs une composante de force radiale en les repoussant contre des butees fixes. L'invention est applicable, notamment, aux moteurs a turbine a gaz d'avions.

Structure de virole de turbine a gaz

Laufschaufelspitzenspaltbreitensteuer- vorrichtung mit nockenbetaetigter mantelringsegmentpositioniervorrichtung

Le dispositif de commande de jeu (72) comporte un mecanisme de positionnement (84) pour commander le jeu qui existe entre des extremites (76A) d'aubes de rotor et un segment d'enveloppe (80) d'un châssis (94) d'un moteur a turbine a gaz ainsi qu'un levier (86) d'actionnement du mecanisme Le mecanisme (84) peut etre actionne pour deplacer radialement le segment d'enveloppe (80) auquel il est fixe afin d'atteindre une position a laquelle un jeu souhaite est etabli Un element formant came externe (94) est fixe a l'extremite externe (90B) d'un arbre (90) Un element formant came interne (96) est fixe a une extremite (86B) du levier (86) Une rotation de l'element formant came interne (96) jointe a une rotation du levier (86) produit un mouvement radial de l'element formant came externe (94) ainsi que de l'arbre (90), ce qui produit un mouvement radial du segment d'enveloppe (80) par rapport aux extremites (76A) des aubes de rotor

Corsmeier Robert James

Papers

Ceramic turbine shroud assembly

Blade tip clearance control apparatus using cam-actuated shroud segment positioning mechanism

Structure de virole de turbine a gaz

Laufschaufelspitzenspaltbreitensteuer- vorrichtung mit nockenbetaetigter mantelringsegmentpositioniervorrichtung

Dispositif de commande du jeu de l'extremite d'une aube utilisant un mecanisme de positionnement d'un segment d'enveloppe commande par came.