Patents Assigned to Alstom (Switzerland) Ltd.
  • Patent number: 6481966
    Abstract: In a gas-turbine guide element (30) around which a hot air flow (23) flows and which, at least in a trailing edge region (21), in which the air flow (23) separates from the guide element (30), comprises at least two walls (10, 11) arranged essentially in parallel and connected to one another by ribs (16, 17, 20) in such a way as to form internal cooling passages (18, 19, 25, 26, 27), and which is cooled on the inside with cooling medium (28, 29) flowing through the cooling passages (18, 19, 25, 26, 27), the cooling medium discharging from the guide element (30) at the trailing edge (21) essentially parallel to and between the walls (10, 11), and in a method of producing it, easier reworking and less susceptibility to foreign particles are achieved owing to the fact that at least some of the ribs are arranged as choke ribs (24) so as to terminate essentially flush with the trailing edge (21).
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: November 19, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventors: Alexander Beeck, Jörgen Ferber, Christoph Nagler, Lothar Schneider, Klaus Semmler
  • Patent number: 6478544
    Abstract: The present invention relates to a blade arrangement with damping elements and to a method of damping vibrations of a blade arrangement. The blade arrangement comprises a rotor and blades arranged on the circumference of the rotor. Damping elements (2, 3) are arranged between the blades and are in contact with the blades due to a centrifugal force, acting in the radial direction, during rotation of the rotor. In this case, at least two damping elements (2, 3) are arranged one behind the other in the circumferential direction of the rotor between adjacent blades, which damping elements (2, 3), during rotation of the rotor, come into contact with one another via a contact surface (6), and of which a first damping element (2) comes into contact with a first friction surface (4) of one of the blades and a second damping element (3) comes into contact with a second friction surface (5) of the other blade. A multiplicity of different vibration states can be effectively damped with the blade arrangement.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: November 12, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventors: Herbert Brandl, Rudolf Kellerer, Brammajyosula Ravindra
  • Patent number: 6471791
    Abstract: The invention relates to a coating which contains large volumetric fractions, preferably from 20 to 90% by volume, of NiAl-&bgr; phase in a &ggr; matrix. It contains the following microalloying elements which increase the ductility of the coating (data in % by weight): 0.1-8 Fe and/or 0.1-8 Mo and/or 0.1-8 Ga, where the total Fe, Mo and Ga content is at most 10%. In addition, small amounts of Zr, C and/or B may be added to the alloy, strengthening the &bgr;/&ggr; phase boundaries.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: October 29, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Mohamed Nazmy, Hans Joachim Schmutzler
  • Patent number: 6470568
    Abstract: In a soldering process for treating tears, recesses, or other material defects in the surface of thermally and mechanically highly stressed components of gas turbines, a nickel foam is applied together with the soldering powder, which can also be mixed with another filler. After this, a heat treatment of the soldering process is performed.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: October 29, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventors: Reinhard Fried, Andreas Bögli
  • Patent number: 6470688
    Abstract: The startup time or the output gradient of a gas turbine plant during startup are limited by the maximum permissible temperature gradient. The increase in the fuel mass flow supplied, if appropriate in combination with the combustion-air mass flow supplied, is consequently also limited. In order to accelerate the startup and to increase the output gradient during startup, then, an additional working medium, for example water or steam, increasing the mass flow flowing through the turbine is supplied at the same time as the fuel mass flow and/or combustion-air mass flow. The output gradient is therefore increased with the maximum permissible temperature gradient remaining the same, so that a required output is reached more rapidly.
    Type: Grant
    Filed: October 29, 2001
    Date of Patent: October 29, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Richard Blatter, Erhard Liebig
  • Patent number: 6471790
    Abstract: The invention relates to a process for the forming of precipitates of carbides and borides along the grain boundaries of an component made from an Ni based superalloy while in solid state. This follows from the finding that the carbides formed by carburization offer similar grain boundary strengthening properties as those cast into the article using the current art without the detrimental effects of adding more carbon to the alloy prior to casting. With advantage the process will be carried out in a way to form secondary caribides in the form Cr23C6, Cr7C, Cr6C and HfC and may take place before, during or after the normal solution and/or precipitation hardening heat treatments of the component.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: October 29, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventor: John Fernihough
  • Patent number: 6463741
    Abstract: A gas turbine set with sequential combustion is provided with a waste-heat boiler suitable for the generation of synthesis gas. The gas turbine set then operates with chemical recouperation of the exhaust-gas heat. By means of such a power plant, efficiencies can be achieved which come close to those of combined cycle plants. The highest efficiencies are achieved when, in a gas turbine set with sequential combustion, the reactor gas is fired, for as large a part as possible, in a combustion chamber of a highest pressure stage. In order to achieve a particular rate of conversion of hydrocarbon-containing crude fuel and superheated steam into synthesis gas, the reactor has to be brought to a minimum temperature which may be above the temperature of the expanded working medium of the gas turbine. This temperature increase can be ensured by means of additional firing. The additional firing may also be used for starting the production of synthesis gas when a starting-air device is present.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: October 15, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventor: Hans Ulrich Frutschi
  • Patent number: 6464460
    Abstract: In an air-cooled turbine blade (10) which has a shroud-band element (11) at the blade tip, the shroud-band element (11) extending transversely to the blade longitudinal axis, hollow spaces (16, 16′, 17, 17′) for cooling being provided in the interior of the shroud-band element (11), which hollow spaces (16, 16′, 17, 17′) are connected on the inlet side to at least one cooling-air passage (18) passing through the turbine blade (10) to the blade tip and open on the outlet side into the exterior space surrounding the turbine blade (10), the hollow spaces (16, 16′, 17, 17′) and the shroud-band element (11) are matched to one another in shape and dimensions in order to reduce the weight of the shroud-band element (11).
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: October 15, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Ibrahim El-Nashar, Beat Von Arx, Bernhard Weigand, Hartmut Haehnle, Rudolf Kellerer
  • Patent number: 6464804
    Abstract: The invention relates to a martensitic-hardenable heat-treated steel, having the following composition (data in % by weight): 9 to 13% Cr, 0.001 to 0.25% Mn, 2 to 7% Ni, 0.001 to 8% Co, at least one of W and Mo in total between 0.5 and 4%, 0.5 to 0.8% V, at least one of Nb, Ta, Zr and Hf in total between 0.001 and 0.1%, 0.001 to 0.05% Ti, 0.001 to 0.15% Si, 0.01 to 0.1% C, 0.12 to 0.18% N, at most 0.025% P, at most 0.015% S, at most 0.01% Al, at most 0.0012% Sb, at most 0.007% Sn, at most 0.012% As, remainder iron and customary impurities, and the proviso that the ratio by weight of vanadium to nitrogen V/N lies in the range between 3.5 and 4.2. After solution annealing at 1050 to 1250° C., cooling to a temperature below 300° C., tempering treatment, partial or complete reaustenitization at 600 to 900° C., cooling to a temperature below 300° C. and annealing at a temperature from 550 to 650° C., it has a high resistance to heat combined, at the same time, with a high ductility.
    Type: Grant
    Filed: May 4, 2001
    Date of Patent: October 15, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Alkan Goecmen, Peter Ernst
  • Patent number: 6461151
    Abstract: According to the invention, in burners having a swirl generator (100), a mixing tube (220) and a combustion chamber (30), the transition from the mixing tube (220) to the combustion chamber (30) is designed with a variable radius over the circumference of the mixing tube (220). As a result, it is possible to form the flame in various shapes—from a circle to an ellipse with a ratio of width to height of 3 at most. The number of burners in a gas turbine may thus be advantageously reduced. Burners of existing gas turbines may be converted in a simple manner.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: October 8, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Hans Peter Knoepfel, Thomas Ruck
  • Patent number: 6461144
    Abstract: In a method of suppressing or controlling thermoacoustic vibrations which develop in a combustion system having a burner working in a combustion chamber due to the formation of coherent or vortex structures and a periodic heat release associated therewith, in which method the vibrations are detected in a closed control loop and acoustic vibrations of a certain amplitude and phase are generated as a function of the detected vibrations and induced in the combustion system, improved suppression is achieved in that, within the control loop, the amplitude of the generated acoustic vibrations is selected to be proportional to the amplitude of the detected vibrations.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: October 8, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Ephraim Gutmark, Christian Oliver Paschereit, Wolfgang Weisenstein
  • Patent number: 6460325
    Abstract: A system (1) generating saturated steam is replaced by at least one gas turbine set (29, 30, 31, 36), at least one waste-heat boiler (32) and at least one back-pressure steam turbine (37). The back-pressure steam turbine (37) is coupled to the gas turbine set (29, 30, 31, 36), which back-pressure steam turbine is supplied by the steam generated in the waste-heat boiler (32). The exhaust steam of the back-pressure steam turbine (37) is supplied to the saturated-steam medium-pressure steam turbine (4).
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: October 8, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventors: Erhard Liebig, Henrik Nielsen
  • Patent number: 6455977
    Abstract: In a generator with an indirectly gas-cooled, in particular air-cooled, stator winding (21), the end regions of the stator bore (23) are to be designed in such a way that the conductor bars are shielded as effectively as possible by the laminated stator core (20) against magnetic fields inducing eddy currents, but, on the other hand, a specific radial dimension between the rotor retaining ring (12) and the laminated stator core (20) is ensured. According to the invention, for this purpose, the end region of the stator bore is designed with four axial zones having a different diameter profile. A first zone (I) is the interior of the stator with the constant nominal stator bore diameter (DI). Toward the end face of the stator is arranged a second zone (II) with a stator bore diameter (DII) widening toward the end face.
    Type: Grant
    Filed: March 15, 2001
    Date of Patent: September 24, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: René-Louis Leyvraz, Francesco Stallone
  • Patent number: 6450769
    Abstract: The present invention relates to a blade assembly with damping elements, which comprises a rotor (5) and blades (6) which are installed on the circumference of the rotor and have a blade platform (7), shank (14) and root (8). A damping element (9) is arranged between respectively adjacent blades (6), said damping element (9) being frictionally connected on rotation of the rotor (5), to at least a first region (1, 2) of a first of the respectively adjacent blades (6), and to a second region (3) of a second of the respectively adjacent blades (6). The blade assembly is characterized by the fact that the damping element (9) is configured and arranged between the first and second blades in such a way that the first region (1, 2) and the second region (3) are located at positions which are significantly spaced apart from one another in the radial direction. This blade assembly provides efficient oscillation damping even in the case of small relative movements between adjacent blades.
    Type: Grant
    Filed: March 8, 2001
    Date of Patent: September 17, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventor: Jaroslaw Szwedowicz
  • Patent number: 6449954
    Abstract: In a process for the recovery of water, which arises from the combustion of a fuel (19), particularly natural gas, in a combined cycle power station (101) including a gas turbine plant (11), a waste heat boiler (33), and a steam turbine (25) arranged in a water/steam circuit with the waste heat boiler (33), and/or which is added in the form of water or steam (36), the water is condensed out from the flue gas (42) arising from the combustion of the fuel (19) and containing water in the form of water vapor after flowing through the waste heat boiler (33), and is separated in liquid form, in particular by expansion in a utilization turbine (20).
    Type: Grant
    Filed: January 12, 2001
    Date of Patent: September 17, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventor: Rolf Bachmann
  • Patent number: 6450245
    Abstract: A heat transfer element assembly for a rotary regenerative air preheater for spacing the heat transfer plates to optimize performance and reduce costs. Rectangular or trapezoidal spacer tabs are punched and bend outwardly from the plates and arranged in parallel rows. The tabs have specific height and length ranges and ratios and the area of the tabs to the area of the remaining portion of the plate has a specific ratio range.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: September 17, 2002
    Assignee: ALSTOM (Switzerland) Ltd.
    Inventor: Jianrong Chen
  • Patent number: 6446710
    Abstract: An arrangement for cooling a flow-passage wall surrounding a flow passage is described, having at least one rib element which induces flow vortices in a flow medium passing through the flow passage, is attached to that side of the flow-passage wall which faces the flow passage, and the shape and size of which are selected in accordance with a certain heat transfer coefficient and a certain pressure loss caused in the flow medium due to the latter flowing over the rib element. The invention is characterized in that the rib element, while largely retaining its original shape and/or size, has contours enlarging its surface facing the flow passage.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: September 10, 2002
    Assignee: ALSTOM (Switzerland) Ltd
    Inventors: Alexander Beeck, Bernhard Bonhoff, Sacha Parneix, Bernhard Weigand
  • Patent number: 6440238
    Abstract: A process for treating the surface of a component prior to coating. The component is made from a Ni based superalloy designed for high temperature service. Both the component and the coating include the elements Al and/or Cr. The process includes depleting the outer surface of the component of any one or a combination of Al, Ti or Cr and thereafter applying the coating directly on the depleted surface. The process minimizes the formation of a brittle gamma prime phase within the interdiffusion zone during service of the component. The process can also be used to renew old damaged coatings.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: August 27, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: John Fernihough, Andreas Bogli, Christoph Tonnes
  • Patent number: 6439136
    Abstract: A (MRFC) solid fuel nozzle tip (12) that is particularly suited to being cooperatively associated with a pulverized solid fuel nozzle (34) of a firing system of the type employed in a pulverized solid fuel-fired furnace (10). The MRFC solid fuel nozzle tip (12) includes fuel air shroud means (46), primary air shroud means (48) located within the fuel air shroud means (46), fuel air shroud support means (50) operative for supporting the primary air shroud means (48) relative to the fuel air shroud means (46), and splitter plate means (52) mounted in supported relation within the primary air shroud means (48). The MRFC solid fuel nozzle tip (12) may be comprised of ceramics including silicon nitride, siliconized silicon carbide, mullite bonded silicon carbide alumina composite, and alumina zirconia composites.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: August 27, 2002
    Assignee: Alstom (Switzerland) Ltd
    Inventors: Jeffrey S. Mann, Ronald H. Nowak
  • Patent number: 6440199
    Abstract: The invention relates to an electric filter which includes emission and separation systems, which are intended for separating particles from a gaseous, particle-containing medium passing through the electric filter, and a filter chamber (1) which surrounds the emission and separation systems and their peripheral devices, the filter chamber (1) having a top surface (2), a base structure (3), and a wall structure (4) provided with thermal insulation and sheet metal cladding. The base structure (3) is made of concrete or the like and includes at least one trough or hopper bottomed tank (5) for the separated particales, wall structure (4) is made of steel and attached to the base structure (3) with a substantially rigid joint (5). The wall structure (4), except for the rigid joint (6), is provided to allow thermal expansion and contraction.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: August 27, 2002
    Assignee: Alstom (Switzerland) Ltd.
    Inventor: Juha Kristiad Tolvanen