Patent•
Ceramic matrix composite component for a gas turbine engine
09 Sep 2002-
TL;DR: In this article, the gap between the CMC member and the support member is kept purposefully small to limit the stress developed in the material when it is deflected against the support by the force of a rubbing blade tip.
Abstract: A ceramic matrix composite (CMC) component for a combustion turbine engine ( 10 ). A blade shroud assembly ( 30 ) may be formed to include a CMC member ( 32 ) supported from a metal support member ( 32 ). The CMC member includes arcuate portions ( 50, 52 ) shaped to surround extending portions ( 46, 48 ) of the support member to insulate the metal support member from hot combustion gas ( 16 ). The use of a low thermal conductivity CMC material allows the metal support member to be in direct contact with the CMC material. The gap ( 42 ) between the CMC member and the support member is kept purposefully small to limit the stress developed in the CMC member when it is deflected against the support member by the force of a rubbing blade tip ( 14 ). Changes in the gap dimension resulting from differential thermal growth may be regulated by selecting an angle (A) of a tapered slot ( 76 ) defined by the arcuate portion.
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28 Jun 2012TL;DR: In this paper, a gas turbine engine is equipped with a shroud segment comprising lowductility material and having a cross-sectional shape defined by opposed forward and aft walls, and opposed inner and outer walls, the walls extending between opposed first and second end faces.
Abstract: A shroud apparatus for a gas turbine engine includes: a shroud segment comprising low--ductility material and having a cross-sectional shape defined by opposed forward and aft walls, and opposed inner and outer walls, the walls extending between opposed first and second end faces, wherein the inner wall defines an arcuate inner flowpath surface, wherein the shroud segment includes: a radially-inward facing chordal forward mounting surface; and a radially-inward facing chordal aft mounting surface; and an annular case surrounding the shroud segment, the case including: a radially-outward facing chordal forward bearing surface which engages the forward mounting surfaces; and a radially-outward facing chordal aft bearing surface which engages the aft mounting surface of the shroud segment.
31 citations
Patent•
23 Jul 2004TL;DR: In this article, an aircraft engine with a shroudless rotor wheel arranged in a flow duct, the flow duct includes a shroud segment formed by a ceramic rubbing coating, which, while having good thermal conductivity, is highly-temperature resistant, attaches firmly to the metallic substrate and is abradable by the tips of the rotor wheel to form a sealing gap as narrow as possible.
Abstract: On an aircraft engine with a shroudless rotor wheel arranged in a flow duct, the flow duct includes a shroud segment ( 1 ) formed by a ceramic rubbing coating ( 3 ) which, while having good thermal conductivity, is highly-temperature resistant, attaches firmly to the metallic substrate ( 2 ) and is abradable by the tips of the rotor wheel to form a sealing gap as narrow as possible, this rubbing coating, owing to the lack of self-insulation, being coolable from a free side of the metallic substrate and, therefore, permitting for working gas temperatures occurring in high-pressure turbines and coating thicknesses sufficient for abrasion.
30 citations
Patent•
31 May 2006TL;DR: In this article, a method for the assembly of a turbine engine is described, which includes providing a shroud support block having a forward end and an aft end, coupling a forward-end of a shroud to the support block using a forward fastener, and coupling an aft-ended end of the shroud with an aft fastener.
Abstract: A method facilitates the assembly of a turbine engine. The method includes providing a shroud support block having a forward end and an aft end, coupling a forward end of a shroud to the shroud support block using a forward fastener, and coupling an aft end of the shroud to the shroud support block using an aft fastener. The method also includes installing a locking pin through the aft fastener to retain the aft fastener, and staking the locking pin in the shroud support block, such that the locking pin is securely coupled to the shroud support block.
28 citations
Patent•
02 Nov 2006TL;DR: In this article, a ring segment for a turbine engine that may be used as a replacement for one or more metal components is presented. But the technique is not suitable for turbine systems that are typically metal.
Abstract: A ceramic ring segment for a turbine engine that may be used as a replacement for one or more metal components. The ceramic ring segment may be formed from a plurality of ceramic plates, such as ceramic matrix composite plates, that are joined together using a strengthening mechanism to reinforce the ceramic plates while permitting the resulting ceramic article to be used as a replacement for components for turbine systems that are typically metal, thereby taking advantage of the properties provided by ceramic materials. The strengthening mechanism may include a ceramic matrix composite overwrap or plurality of overwraps designed to help prevent delamination of the ceramic plates when the ceramic article is in use by placing the plates in compression.
27 citations
Patent•
05 May 2006TL;DR: In this article, the authors proposed a multi-layer ring seal segment that can incorporate a plurality of material systems, including an inner layer, a central layer and an outer layer, which can take advantage of the benefits of the different materials so as to better withstand the operational loads of the turbine.
Abstract: Aspects of the invention are directed to a multi-layer ring seal segment that can incorporate a plurality of material systems. The ring seal segment can include an inner layer, a central layer and an outer layer. The inner layer can be attached to one side of the central layer, and the outer layer can be attached to an opposite side of the central layer. The inner and outer layers can be made of a ceramic matrix composite, such as a hybrid oxide ceramic matrix composite or an oxide-oxide ceramic matrix composite. The central layer can be made of a material that has high shear strength relative to the inner and outer layers. The ring seal segment according to aspects of the invention can take advantage of the benefits of the different materials so as to better withstand the operational loads of the turbine.
27 citations
References
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Patent•
11 Feb 1999TL;DR: In this article, a ceramic composition for insulating components, made of ceramic matrix composites, of gas turbines is provided, which comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the binder partially fills gaps between the spheres and the filler powders.
Abstract: A ceramic composition for insulating components, made of ceramic matrix composites, of gas turbines is provided. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere and the arrangement of spheres is such that the composition is dimensionally stable and chemically stable at a temperature of approximately 1600 °C. A stationary vane of a gas turbine comprising the composition of the present invention bonded to the outer surface of the vane is provided. A combustor comprising the composition bonded to the inner surface of the combustor is provided. A transition duct comprising the insulating coating bonded to the inner surface of the transition is provided. Because of abradable properties of the composition, a gas turbine blade tip seal comprising the composition also is provided. The composition is bonded to the inside surface of a shroud so that a blade tip carves grooves in the composition so as to create a customized seal for the turbine blade tip.
141 citations
Patent•
15 Nov 1985
TL;DR: A turbine ring has an annular metallic carrier which is mounted within the inside of the turbine casing and within the carrier there is provided a ceramic abradable ring as mentioned in this paper, and a cooling air circuit is provided to regulate the temperature of only the annular carrier such that the latter always exerts a centripetal compression force on the ring under all operational conditions of the gas turbine.
Abstract: A turbine ring has an annular metallic carrier which is mounted within the inside of the turbine casing and within the carrier there is provided a ceramic abradable ring. A cooling air circuit is provided to regulate the temperature of only the annular carrier such that the latter always exerts a centripetal compression force on the ring under all operational conditions of the gas turbine to clamp the abradable ring.
69 citations
Patent•
21 Apr 1987
TL;DR: In this paper, a turbine ring comprises an annular support in two parts and a ring of ceramic sectors for sealing purposes, which are interconnected by an axial groove and a sliding male part.
Abstract: A turbine ring comprises an annular support in two parts and a ring of ceramic sectors for sealing purposes. The two parts of the support are interconnected by an axial groove and a sliding male part. Each part comprises an axial annular groove in which is engaged a respective axial edge portion of each sector. The cooperating internal radial faces respectively of the edge portion and of the groove are circumferential, while the radially outer radial face of each sector comprises at least one flat zone. The corresponding face of each groove may be polygonal.
61 citations
Patent•
26 May 1983
TL;DR: In this article, the ceramic facing material of an outer air seal (30) at the leading edge region (36) is densified by a plasma gun to produce a glazed area (52) which is resistant to erosion.
Abstract: Outer air seal structures of particular suitability for use in gas turbine engines are disclosed. Techniques for improving resistance to erosion while maintaining good abradability are discussed. In one particular structure the ceramic facing material of an outer air seal (30) at the leading edge region (36) is densified by a plasma gun to produce a glazed area (52) which is resistant to erosion.
61 citations
Patent•
14 Jan 1991TL;DR: In this paper, a turbine blade shroud assembly for a gas turbine engine includes a metal substrate ring on the engine, a continous ceramic barrier ring inside the substrate ring and exposed to hot gas in a hot gas flow path of the engine and a wire mesh compliant ring between the barrier and substrate rings.
Abstract: A turbine blade shroud assembly for a gas turbine engine includes a metal substrate ring on the engine, a continous ceramic barrier ring inside the substrate ring and exposed to hot gas in a hot gas flow path of the engine, and a wire mesh compliant ring between the barrier and substrate rings. The temperature of the barrier ring increases faster than the temperature of the substrate ring as the temperature in the hot gas flow path increases. The coefficient of thermal expansion of the substrate ring is less than the coefficient of thermal expansion of the barrier ring so that the barrier ring expands relative to the substrate ring with increasing temperature in the hot gas flow path and development of tensile hoop stress in the ceramic barrier ring is minimized.
60 citations