Abstract: Protection device for a stator of a turbine comprising a series of annular sectors (12) which can be coupled by connection means, each sector (12) comprising a first side surface (13) which has at least one cavity (14) equipped with a bottom (15), each bottom (15) of the at least one cavity (14) is convex and each sector (12) comprises at least one stiffening rib (16) positioned inside the at least one cavity (14) and having a variable section in a longitudinal direction to modulate the rigidity of each sector (12).

Abstract: On a two or multi-stage turbine, expansion rings are provided in all stages at the sides of the rotors for passive, continuous running gap control whose thermal expansion and contraction behavior corresponds to that of the rotors and which are connected to radially moveable upstream and downstream stator vanes (5, 7). The downstream stator vanes are assembled to the upstream stator vanes via a bridge (16; 17, 18) which is axially and circumferentially fixed and located flexibly in the radial direction on the outer casing (10) of the turbine. The stator vanes (6) arranged between the rotor disks are integrally connected to the bridge or, as separate components, held axially and circumferentially on the bridge to take up rolling and tilting moments.

Abstract: A system for attaching a ring seal to a vane carrier in a turbine engine can allow the ring seal to radially expand and contract at least partially independently of the vane carrier. The system can also be configured to substantially restrict axial and/or circumferential movement of the ring seal. In one embodiment, the ring seal can include a plurality of radial slots circumferentially spaced about the ring seal. A pin can extend substantially through each of the slots and into operative engagement with isolation rings, which are connected to the vane carrier. In another embodiment, the ring seal and the isolation rings can include a series of axially-extending protrusions extending substantially circumferentially about each component. The protrusions on the ring seal can substantially matingly engage the protrusions on the isolation rings. The protrusions can be configured as a Hirth coupling.

Abstract: A method for assembling a gas turbine engine includes coupling an axisymmetric structure within the gas turbine engine, wherein the axisymmetric structure includes at least one mounting bushing extending from a radially outer surface of the axisymmetric structure, and inserting a pin having a crowned surface at least partially into the mounting bushing such that the pin provides both axial and tangential support to the axisymmetric structure, and securing the pin to the gas turbine engine utilizing a retaining assembly.

Abstract: Aspects of the invention relate to a modular turbine vane assembly. The vane assembly includes an airfoil portion, an outer shroud and an inner shroud. The airfoil portion can be made of at least two segments. Preferably, the components are connected together so as to permit assembly and disassembly of the vane. Thus, in the event of damage to the vane, repair involves the replacement of only the damaged subcomponents as opposed to the entire vane. The modular design facilitates the use of various materials in the vane, including materials that are dissimilar. Thus, suitable materials can be selected to optimize component life, cooling air usage, aerodynamic performance, and cost. Because the vane is an assemblage of smaller sub-components as opposed to one unitary structure, the individual components of the vane can be more easily manufactured and more intricate features can be included.

Abstract: A seal arrangement 32 between a turbine shroud seal segments 38,40 in a gas turbine engine. The arrangement 32 comprises facing slots 34, 36 provided respectively in the segments 38,40 with offset spaces 42, 44 provided between the segments 38,40. A strip 46 is cemented into the slot 36 such that the flow path 50 passes through the space 42, around the free end of the strip 46, and out through the offset space 44, thereby providing a longer flow path.

Abstract: The present invention is a shroud tip clearance control ring for use in a gas turbine engine in which a rotary blade and a shroud ring form a gap that forms a blade outer air seal, and where the shroud ring is formed of two shroud segment halves, each shroud segment including a pin located near an end of the segment, the pins being slidably within slots formed on the casing, and a drive member moves along a direction in which the pins are moved along the slots to change a radius of the shroud ring in a way such that the radius remains substantially the same along a 360 degree angle of the shroud ring. The drive member includes two positions, one that places the shroud ring in a radially inward position, and another position that places the shroud ring in a radially outward position.

Abstract: A spacer arrangement 1, 40 is provided in which wedges 5, 6; 45, 46 are arranged to have an interface 7, 47 between them such that a thermally variable member 8, 48 can cause relative motion between the wedges 5, 6; 45, 46 to adjust an arrangement lateral dimension dependent upon temperature. In such circumstances with the arrangement 1, 40 positioned within a gap 3 between a casing 14 and unison ring 13, retention of position of that unison ring 13 can be maintained. The unison ring is arranged to adjust position of variable vanes.

Abstract: A turbine section of an engine that includes a shaft, a plurality of blades extending radially relative to the shaft, a bearing assembly, a flowpath housing, and a shroud is provided. The bearing assembly is mounted to the shaft adjacent to the plurality of blades. The flowpath housing is coupled to the bearing assembly and includes an inner cylinder, an outer cylinder, and a strut. The inner and outer cylinders each include a strut attachment point between which the strut is coupled, and the outer cylinder includes an outer surface. The shroud is disposed concentric to the outer cylinder and has an inner surface including a groove formed therein that is substantially aligned with the outer cylinder strut attachment point. The groove has a depth that provides and maintains a gap between the outer cylinder outer surface and the shroud inner surface when the flowpath housing is exposed to heat and the strut radially expands.

Abstract: A device for tuning clearance at rotor blade tips in a gas turbine rotor, the device comprising at least one annular air flow duct that is mounted around the circumference of an annular casing of a stator of the turbine, the annular air flow duct being designed to discharge air onto the casing in order to modify the temperature thereof. A tubular air manifold is disposed around the air flow duct(s). There are also disposed an air feed tube to supply the tubular air manifold with air and an air pipe opening in the tubular air manifold and opening out into the air flow duct(s). The air pipe is provided with a balancing diaphragm for balancing the air flowing through the pipe.

Abstract: A device for fastening a turbocharger to a base, with a fastening foot (12) which is integrally formed in one piece on a gas outlet casing (10) of the turbocharger and which has long holes (16) spaced from one another and preferably arranged in a star-shaped manner in relation to one another. In order to fasten the turbocharger, sliding shoes (26) are capable of being inserted into the long holes (16) and have continuous orifices, through which can be led fastening elements (30, 30?) capable of being fixed in the base.

Abstract: The clearance between the tips of the rotor blades and the segmented shroud of a gas turbine engine is controlled by a passive clearance control that includes a support ring made from a low thermal expansion material supporting a retainer for the blade outer air seal that is slidable relative thereto so that the segments expand circumferentially and move radially to match the rate of change slope of the rotor during expansion and contraction for all engine operations. A leaf spring between the support ring and outer air seal biases the outer air seal in the radial direction and maintains the desired radial position during steady state operation of the gas turbine engine.

Abstract: A turbine shroud segment attachment with a casing (1) and several shroud segments (2) arranged in the casing (1), wherein the individual shroud segments (2) are located in the casing (1) with a circumferential clearance (3) between the individual shroud segments (2), in that the clearance (3) is reduced to zero at a given temperature difference between the casing (1) and the shroud segments (2), and in that the shroud segments (2) are retained on the casing (1) by way of an elastically deformable locating arrangement.

Abstract: A drum-type rotor carries an annular row of moving blades having root portions held within a slot in the periphery of the rotor. A turbine casing surrounds the rotor and carries a static blade assembly with an annular row of static blades which, together with the annular row of moving blades, constitutes an impulse turbine stage. The static blade assembly has a radially inner static ring confronting a periphery of the rotor with a seal acting therebetween. The static blade assembly has an outer static ring which has a substantially greater thermal inertia and stiffness then the inner static ring and is capable of sufficient radial sliding relative to the casing so as to accommodate relative thermal expansion and contraction of the outer static ring and the turbine casing.

Abstract: A cooling arrangement (17) for supplying a first cavity (9) with a cooling gas, in particular in a gas turbine of a power plant, includes a cooling-gas passage (19) which is formed in a first component (6) and connects the first cavity (9) to a second cavity (10 ). A second component (16 ) bears against a bearing side (15) remote from the second cavity (10 ) and separates the first cavity (9) from a third cavity (12). The second component (16 ) is displaceable within a range of displacement. To improve the cooling effect, an orifice region (20) of the cooling-gas passage (19) is dimensioned and/or positioned in such a way that its orifice cross section (21) projects from the range of displacement to such an extent that it is open at least with a predetermined minimum cross section in any position of the second component (16 ).

Abstract: The exhaust-gas turbine comprises a turbine wheel arranged on a shaft, a bearing casing for the bearing arrangement of the rotatable shaft, a gas-inlet casing supported on the bearing casing and concentrically surrounding the bearing casing in the supporting region, and a centering ring for centering the gas-inlet casing relative to the shaft mounted in the bearing casing. The centering ring and either the bearing casing or the gas-inlet casing comprise grooves and either radially or axially unidirectional centering lugs for engaging in the grooves. Due to the radially or axially unidirectional centering lugs with corresponding grooves, at least one of the connections between the bearing casing and the centering ring and the centering ring and the gas-inlet casing is not positive-locking, as a result of which any desired positioning of the gas-inlet casing relative to the bearing casing is made possible.

Abstract: A drop-in nozzle block (40) formed in two 180° segments (52) that can be simply lowered into position within the nozzle chamber casing of a steam turbine (42). An entire 180° segment can be lowered into position because an inner arcuate portion (58) of the nozzle block fits over and captures mating portions of the casing rather than having the casing capture the nozzle block as in the prior art. Elimination of a hook portion of the casing eliminates the necessity for the prior art procedure of rotating 90° segments into position through an arcuate-shaped slot. The drop-in installation allows closer tolerances to be maintained between the nozzle block and the casing, thereby eliminating the need for the expansion pins used in the prior art. The use of two 180° segments rather than the prior art 90° segments also eliminates the need for a dogleg joint between segments for turbines having eight steam inlet segments.

Abstract: The invention concerns a casing aggregate for the turbine of an exhaust turbocharger. The invention is identified by the following characteristics: a spiral casing adapted for surround the running wheel of the turbine; a tongue-like wall part (tongue) in the inside of the spiral casing; an inlet connection; an outlet connection; a flange to connect to a bearing casing; wherein the casing aggregate is manufactured of thin-walled precision casting; wherein the casing aggregate is made of at least two parts, so that at least one separation joint is present; and the separation joint is arranged as follows: it runs in an axially perpendicular level; it runs along the apex line of the spiral casing; it extends over an arc of a circle of approximately 270 degrees; it lies outside of the area of the tongue.

Abstract: A bypass duct sealing grommet, for sealing between an opening in a gas turbine engine bypass duct wall and the external surface of a projection extending through the opening, where the grommet has an annular body with a central aperture having an interior periphery adapted to sealingly engage the external surface of the projection. A first flange and second flanges define an external slot about an exterior periphery of the body adapted to receive and seal the bypass duct wall between the flanges.

Abstract: A structure for attaching together or sealing a space between a first component and a second component that have different rates or amounts of dimensional change upon being exposed to temperatures other than ambient temperature. The structure comprises a first attachment structure associated with the first component that slidably engages a second attachment structure associated with the second component, thereby allowing for an independent floating movement of the second component relative to the first component. The structure can comprise split rings, laminar rings, or multiple split rings.

Abstract: A turbine includes, in an exemplary embodiment, an outer housing, a turbine shaft rotatably supported in the outer housing, and a plurality of turbine stages located along the turbine shaft. Each turbine stage includes a diaphragm attached to the casing, a rotor having a plurality of buckets and a bucket cover fixedly attached to the turbine shaft, and a packing ring mounted in a first circumferentially extending groove in said diaphragm. The packing ring includes a seal shroud and a sealing means and is positioned adjacent the turbine shaft. The seal shroud is fabricated from a first material having a first coefficient of expansion, and the is diaphragm fabricated from a second material having a second coefficient of expansion. The first and second materials are selected so that at a first temperature a gap between the turbine shaft and the diaphragm is larger than at a second higher temperature.

Abstract: An easy-fit heat screening device (110) for connecting a cooling pipe (112) and a through-hole (114) formed in a nozzle support ring (116) of a gas turbine, of the type comprising a tubular structure (118) which has an external diameter smaller than a diameter of the through-hole (114) and into which the cooling pipe (112) extends; this tubular structure (118) has at the top a shaped annular end (126) which is inserted inside a groove (130) formed in the through-hole (114).

Abstract: The clearance between the tips of the rotor blades and the segmented shroud of a gas turbine engine is controlled by a passive clearance control that includes a support ring made from a low thermal expansion material supporting a retainer for the blade outer air seal that is slidable relative thereto so that the segments expand circumferentially and move radially to match the rate of change slope of the rotor during expansion and contraction for all engine operations. A leaf spring between the support ring and outer air seal biases the outer air seal in the radial direction and maintains the desired radial position during steady state operation of the gas turbine engine.

Abstract: A gap seal in a gas turbine for sealing off a cooling space, formed between a heat shield and a heat shield carrier, from a hot gas space of the gas turbine. A sealing body is retained in a movable manner on the heat shield, on the one hand, and on a blade carrier, on the other hand, adjacent to the heat shield carrier.

Abstract: A suspension of an annular secondary structure on a primary structure, in the form of a spoke-type centering device, has at least three sliding guides distributed uniformly over the structure circumference. Each sliding guide allows at least a linear relative movement of the structures transversely to their axial direction. The linear direction of movement of each sliding guide runs, in relation to the structure-related radial direction at the location of the sliding guide, at an angle having radial and tangential direction components.

Abstract: 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.

Abstract: A plurality of arcuate circumferentially spaced supply and return manifold segments are arranged on the rim of a rotor for respectively receiving and distributing cooling steam through exit ports for distribution to first and second-stage buckets and receiving spent cooling steam from the first and second-stage buckets through inlet ports for transmission to axially extending return passages. Each of the supply and return manifold segments has a retention system for precluding substantial axial, radial and circumferential displacement relative to the rotor. The segments also include guide vanes for minimizing pressure losses in the supply and return of the cooling steam. The segments lie substantially equal distances from the centerline of the rotor and crossover tubes extend through each of the segments for communicating steam between the axially adjacent buckets of the first and second stages, respectively.

Abstract: A tubular connector adapted to extend between two tubular components comprising a tubular body having an internal diameter, a first free end including an annular radial flange having a tapered surface adapted to engage a complementary seating surface on a first of the two tubular components, the internal diameter remaining constant through the first free end; and a second free end having an annular bulbous shape adapted to seat within a cylindrical end of a second of the two tubular components.

Abstract: At least one airfoil shaped vane made of a low ductility material, for example a ceramic base material such as a ceramic matrix composite or an intermetallic material such as NiAl material, is releasably carried in a turbine vane assembly including inner and outer vane supports by at least one high temperature resistant compliant seal. The seal isolates the vane from at least one of the vane supports and allows independent thermal expansion and contraction of the vane in respect to the support.

Abstract: A method of operating a gas turbine having inner and outer shells, with the inner shell being radially movable relative to rotor bucket tip passage in the inner shell for flowing a thermal medium. A pair of passage portions are formed in each of the aft and forward inner shell sections with axially communicating passageways between the passage portions. A thermal medium, preferably from an off-turbine site, is provided for flow through the second-stage aft inner shell section, along axial passageways along the mid-line of the inner shell to a first passage portion of the forward inner shell section. Cross-over paths flow the thermal medium from the first passage portions to second circumferentially extending passage portions of the forward inner shell section, in turn, in communication with axial passageways extending from the forward section to the aft section. A second pair of passage portions flow the thermal medium to an outlet in the aft section.

Abstract: A device for positioning of nozzles of a stator stage and for cooling of rotor discs in gas turbines, of the type including nozzle segments consisting of several airfoils. Each nozzle segment is connected at its top to an outer ring to define a chamber containing cooling air and is positioned at its base on an inner ring. The nozzle segments form a circumferential array about the axis of the gas turbine. In each airfoil of the nozzle segment, there is provided at least one tube, which is inserted in a corresponding duct inside the airfoil for delivering cooling air to the first and second stage discs.

Abstract: A nozzle vane or airfoil structure is provided in which the nozzle ribs are connected to the side walls of the vane or airfoil in such a way that the ribs provide the requisite mechanical support between the concave side and convex side of the airfoil but are not locked in the radial direction of the assembly, longitudinally of the airfoil. The ribs may be bi-cast onto a preformed airfoil side wall structure or fastened to the airfoil by an interlocking slide connection and/or welding. By attaching the nozzle ribs to the nozzle airfoil metal in such a way that allows play longitudinally of the airfoil, the temperature difference induced radial thermal stresses at the nozzle airfoil/rib joint area are reduced while maintaining proper mechanical support of the nozzle side walls.

Abstract: A casing for the fan section of an aircraft gas turbine engine of the turbofan type. The casing includes an inner filler material and is defined by an outer shell and an inner liner that is spaced radially inwardly from the outer shell. The inner liner is held in position relative to the outer shell by a plurality of radially-inwardly-extending support pins. The pins are carried by the outer shell and are slidably received in and extend at least partially into the inner liner. The support pins retain the inner liner against axial and rotational movement relative to the outer shell, while allowing relative radial movement therebetween in response to thermal expansion and contraction, as well as in response to aircraft maneuver loads imposed on the engine.

Abstract: A nozzle vane or airfoil structure is provided in which the nozzle ribs are connected to the side walls of the vane or airfoil in such a way that the ribs provide the requisite mechanical support between the concave side and convex side of the airfoil but are not locked in the radial direction of the assembly, longitudinally of the airfoil. The ribs may be bi-cast onto a preformed airfoil side wall structure or fastened to the airfoil by an interlocking slide connection and/or welding. By attaching the nozzle ribs to the nozzle airfoil metal in such a way that allows play longitudinally of the airfoil, the temperature difference induced radial thermal stresses at the nozzle airfoil/rib joint area are reduced while maintaining proper mechanical support of the nozzle side walls.

Abstract: 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.

Abstract: A sealing device for a gas turbine stator blade, in which an outer shroud (32) is mounted by heat insulating rings (32a,32b) on a blade ring (50). The blade ring (50) has a first air hole (1), which communicates with a space (53), and a second air hole (51), which communicates with a seal tube (2). The seal tube (2) is inserted into the second 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 removably secure the seal tube (2). Cooling air (54) flows through the first air hole (1) to cool the shrouds and the inside of a stator blade (31) until it is released from the trailing edge of the blade. The cooling air also flows into a cavity (36) so that a high pressure can be maintained without a pressure loss because the tube (2) is independent of the space (53) in the blade ring.

Abstract: Today, the trend is to increase the temperature of operation of gas turbine engines. To cool the components with compressor discharge air, robs air which could otherwise be used for combustion and creates a less efficient gas turbine engine. The present low thermal expansion sealing ring support system reduces the quantity of cooling air required while maintaining life and longevity of the components. Additionally, the low thermal expansion sealing ring reduces the clearance "C","C'" demanded between the interface between the sealing surface and the tip of the plurality of turbine blades. The sealing ring is supported by a plurality of support members in a manner in which the sealing ring and the plurality of support members independently expand and contract relative to each other and to other gas turbine engine components.

Abstract: A turbine assembly having a turbine stator, a ceramic inner shroud, and a first spring. The stator has a longitudinal axis and an outer shroud block with opposing and longitudinally outward facing first and second sides. The first side has a longitudinally outward projecting first ledge and has a first side portion located radially outward of the first ledge. The ceramic inner shroud has a first hook portion longitudinally and radially surrounding the first ledge. The first spring is attached to one of the first side portion and the first hook portion and unattachedly and resiliently contacts the other of the first side portion and the first hook portion.

Abstract: A bearing gallery thermal movement isolation device permits the inner bearing support ring of the bearing gallery to float freely relative to the outer bearing gallery housing under thermal expansion and contraction during engine operation without transmitting thermally induced movement or forces to the oil supply and scavenge lines, or to the cooling air supply line. An oil transfer tube isolation connector is disposed on an inward end of the transfer tube and on the bearing gallery. The connector includes a radially extending sleeve on the inner bearing support ring; and a sliding O-ring engaging the sleeve and transfer tube. An oil scavenge canal is defined between the O-ring and a threaded connection between the transfer tube and the oil supply boss of the bearing gallery.

Abstract: The high pressure inlet bleed heat system includes a plurality of tubes which receive heated compressed air from the compressor extraction discharge manifold. The tubes extend into the inlet duct of the compressor, are uniformly spaced one from the other and have a uniform distribution of laterally opening apertures along their lengths in registration with the apertures of next laterally adjacent tubes. The tubes are located downstream of the silencer baffles. By providing choked flow through the apertures and lateral registration of the apertures of adjacent tubes, complete mixing of the heated air with the inlet air vortices behind the silencer baffles is achieved, affording a uniform temperature distribution across the inlet duct with minimum pressure loss. The tubes are constructed to accommodate thermal expansion of the manifold receiving compressor discharge air, the manifold also being supported to accommodate thermal expansion and contraction.

Abstract: A cooling medium path structure for cooling a gas turbine blade. The structure includes a disk-side cooling medium path, a blade-side cooling medium path formed at the root portion of the blade and a delivery block disposed between the two cooling medium paths so as to establish communication therebetween. The delivery block is provided with an elastic engaging section which comes into elastic and line-contact with the disk-side cooling medium path and the blade-side cooling medium path. Thus, the sealing property of the contact portions of the structure is secured so as to allow a cooling medium to be supplied without leaking from the cooling medium paths. The heat of the cooling medium, generated as a result of cooling the high-temperature portion of the gas turbine, can be recovered so as to make the best use of the heated medium.

Abstract: A sealing element seals a gap which may be formed between two components that are movable thermally relative to one another. Each component has a component groove located one opposite the other. The sealing element is directed along a center line, in a cross-section essentially perpendicular to a main line, and has a first end, a second end located opposite the first end and a toothed middle region located between the ends. The sealing element is suitable in particular for sealing off a gap between guide blades at high temperatures in a gas turbine plant for the purpose of preventing a gas flow out of a cooling-gas region into a hot-gas region. A gas turbine plant is provided with the sealing element for sealing the gap.

Abstract: A baffle plate (12A) is constructed such that two belt-like elements, bent in a warped arc, are joined by spot welding (13) or brazing (14) at a central portion thereof along a central circumferential portion. Thus, even if there is a difference in a radial directional deflection of grooves (11) between adjacent discs (9), the baffle plate (12A) will maintain close contact with the inner surfaces of the grooves (11) due to a spring effect and gas leakage is thereby prevented.

Abstract: In order to create an adjusting ring for the synchronous alteration of the angle of pitch of guide vanes of a compressor having several bearing points for mounting on a compressor housing of the compressor, which can be manufactured at least partially from materials with a low coefficient of thermal expansion and is, nevertheless, compatible with a metallic compressor housing with respect to temperature, it is suggested that the adjusting ring comprise curved ring segments each arranged between two adjacent bearing points, the curvature of the ring segments decreasing during an increase in the temperature of the ring segments so that the bearing points between the ring segments are displaced outwards in a radial direction.

Abstract: An improved heat insulation assembly for a thermal turbo-engine having hollow spaces, is provided with the assembly including a heat-insulating material enclosed within a heat-resistant cover that is formed such that it permits an increase in the inner volume, and the heat-insulating material being a heat-insulating material which increases its volume upon heating to such an extent that the cover is expandable until contact with the inner side of a corresponding hollow space.

Abstract: In a turbine inclusive of:a turbine shaft having a longitudinal axis, a steam pipe, a shell circumadjacent the pipe, the pipe and shell being shiftable in vertical and transverse and axial directions relative to the longitudinal axis of the shaft, and a seal assembly disposed between the pipe and shell and comprising a stack of interdigitated relatively large and small piston rings, the improvement comprising: placement of the stack of large and small rings into a circular container which is inserted into the shell with adequate clearance to permit thermal expansion, the container being provided with a flexible seal to the shell and having thermal inertia similar to that of the rings and the pipe.

Abstract: A gas turbine engine's nozzle structure includes a nozzle support ring, a plurality of shroud segments, and a plurality of airfoil vanes. The plurality of shroud segments are distributed around the nozzle support ring. Each airfoil vane is connected to a corresponding shroud segment so that the airfoil vanes are also distributed around the nozzle support ring. Each shroud segment has a hook engaging the nozzle support ring so that the shroud segments and corresponding airfoil vanes are supported by the nozzle support ring. The nozzle support ring, the shroud segments, and the airfoil vanes may be ceramic.

Abstract: An improved bell seal arrangement for steam turbines wherein the bell seal is modified by the addition of a special, replaceable, cylindrical extension seal for sealing the leakage gap between the bell seal and the turbine inner shell, the extension seal being threadably attached and secured to the modified bell seal to insure against vibration, and when wear or damage occurs to the extension seal surface, being replaceable without requiring complete removal or replacement of the modified, existing bell seal.

Abstract: An improved bell seal arrangement for steam turbines is provided that allows the bell to expand thermally without damage to the opposing seal surface of the inner shell by the addition of components that allow yielding of the seal surface without causing permanent distortion or surface damage.

Abstract: In a turbine inclusive of: a turbine shaft having a longitudinal axis, a steam pipe, a casing circumadjacent the pipe, the pipe and casing being shiftable in vertical and transverse and axial directions relative to the longitudinal axis of the shaft, and a seal assembly disposed between the pipe and casing and comprising a stack of interdigitated relatively large and small piston rings, each large ring loosely fitting inside the shell during nonoperative conditions and having teeth firmly and sealingly engaging the casing during operative conditions; and having a coefficient of thermal expansion greater than that of the casing for expanding at a rate faster than the expansion rate of the casing under a condition of increased temperature, each small ring loosely fitting around the pipe during nonoperative conditions and having teeth firmly and sealingly engaging the pipe during operative conditions; and having a coefficient of thermal expansion less than that of the pipe for expanding at a rate slower than the