Patents by Inventor David B. Allen

David B. Allen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7836591
    Abstract: A method of forming an interstage seal including removing a diaphragm seal box (14) from a gas turbine compressor assembly (10) and removing a labyrinth sealing member (12) from the diaphragm seal box (14). An abradable material layer (34) may be deposited on the diaphragm seal box (14). A spray gun may be mounted in relation to an engine disk (16) of the gas turbine compressor assembly (10) for cold-spraying a quantity of particles toward the engine disk (16). The particles may be sprayed at a velocity sufficiently high to cause at least a portion of the quantity of particles to adhere to the engine disk (16). The spray gun may be controlled to deposit a quantity of particles on the compressor disk (16) to form a geometry (32) that will abrade the abradable material layer (34) during operation of the gas turbine compressor assembly (10). The geometry (32) abrading the abradable material layer (34) forms an interstage seal.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: November 23, 2010
    Assignee: Siemens Energy, Inc.
    Inventors: David B. Allen, Ramesh Subramanian
  • Patent number: 7784264
    Abstract: One embodiment of a transition-to-turbine seal (300) comprises a first, flattened section (302) adapted to be received in a peripheral axial slot (320) of a transition (325), and a second, generally C-shaped section (301). The generally C-shaped section (301) comprises a flattened portion (305) near the first, flattened section (302), and a curved portion (306) extending to a free edge (307). A fiber metal strip component (309) may be attached to the flattened portion (305) to define a first engagement surface adapted to engage an upstream side (336) of an outer vane seal rail (337), and a second engagement surface 308, adjacent the free edge (307), provides an opposed wear surface adapted to engage a downstream side (338) of the outer vane seal rail (337). System embodiments also are described, in which such transition-to-turbine seal (300) is isolated from a hot gas path (350) by provision of a plurality of cooling apertures (327) in the transition (325).
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: August 31, 2010
    Assignee: Siemens Energy, Inc.
    Inventors: Adam J. Weaver, Raymond S. Nordlund, David B. Allen, Daniel O. Davies
  • Patent number: 7686570
    Abstract: This invention relates to an abradable coating system for use in axial turbine engines. When coated onto a turbine ring seal segment the coating system may allow formation of an individualized seal between turbine blade disks and the surrounding ring seal without causing excessive wear to the blade tips. The abradable coating system includes columns of an abradable material. Thus, interference between the blades and the abradable coating system causes the individual columns to break off at the base. This abrasion mechanism may reduce blade wear and spalling of the coating system when compared to conventional coatings.
    Type: Grant
    Filed: August 1, 2006
    Date of Patent: March 30, 2010
    Assignee: Siemens Energy, Inc.
    Inventor: David B. Allen
  • Publication number: 20100050649
    Abstract: A combustor device and transition duct assembly is provided for use in a gas turbine engine. The combustor device comprises combustor structure having an exit portion; spring clips mounted to the exit portion of the combustor structure; and a burner assembly. The transition duct comprises a conduit having inlet and outlet sections and an abradable material layer provided along a circumferential portion of the inlet section of the transition duct conduit. The transition duct conduit inlet section may be coupled to the combustor structure exit portion such that the spring clips engage the abradable material layer.
    Type: Application
    Filed: September 4, 2008
    Publication date: March 4, 2010
    Inventor: David B. Allen
  • Publication number: 20100015350
    Abstract: A process (20) of producing an abradable thermal barrier coating (38) with a uniformly distributed solid lubricant (46) such as for gas turbine shroud ring segments. A mixture of a ceramic precursor powder (23) and a solid lubricant precursor powder in a liquid (22) is injected (28) into a thermal jet (32), such as one generated by a plasma gun (30). The precursor powders (23, 24) are dissolved or suspended in the liquid, forming a uniform spray mix (34) that is atomized in the thermal jet (32). The resulting spray mix (34) is directed toward a substrate (36), producing layers (39a-39c) of overlapping adherent ceramic splats (42) surrounded generally uniformly by an amount of solid lubricant (46) sufficient to increase abradability of the layers to a given degree, and thus protect turbine blade tips from damage during adjacent rotation with zero clearance.
    Type: Application
    Filed: July 16, 2008
    Publication date: January 21, 2010
    Applicant: SIEMENS POWER GENERATION, INC.
    Inventor: David B. Allen
  • Patent number: 7604455
    Abstract: Aspects of the invention are directed to a system for improving engine performance by reducing vane tip clearances in the compressor section of a turbine engine. According to aspects of the invention, an abrasive material can be attached to a rotor disc. Thus, if a vane tip contacts the rotor disc during engine operation, the vane tip is worn away by the abrasive material. The system can reduce the risk of substantial component damage resulting from a vane tip rubbing event. The abrasive material can be provided in the form of an insert that can be removably attached to the rotor disc. Thus, the insert can be readily removed and replaced when necessary.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: October 20, 2009
    Assignee: Siemens Energy, Inc.
    Inventors: Hubertus E. Paprotna, David B. Allen, Oran L. Bertsch
  • Publication number: 20090258247
    Abstract: A layered abradable thermal barrier coating (TBC) 20 that is stable, abradabie, and sinter resistant up to about 1400° C. A tungsten bronze structured ceramic of the form Ba6?3xRE8+2xTi18O54, where 0<x<1.5, and RE represents a rare earth lanthanide cation, is applied as a topcoat over a yttria stabilized zirconia (YSZ) undercoat (18) on a bond-coated (17) superalloy metal structure (16). The tungsten bronze structure provides abradability and thermal conductivity. The YSZ layer is a proven concept for thermal barrier coatings, and has demonstrated better adhesion than newer chemistries This combination of layers has synergy that takes advantage of both materials to provide an abradable coating with an extended lifespan on a superalloy substrate compared to prior coatings. The topcoat may be applied with fugitive inclusions that produce porosity to increase abradabilty for improved blade tip clearance control in the turbine section of gas turbines.
    Type: Application
    Filed: April 11, 2008
    Publication date: October 15, 2009
    Applicant: SIEMENS POWER GENERATION, INC.
    Inventors: Anand A. Kulkarni, David B. Allen
  • Publication number: 20090148278
    Abstract: This invention relates to an abradable coating system for use in axial turbine engines. When coated onto a turbine ring seal segment the coating system may allow formation of an individualized seal between turbine blade disks and the surrounding ring seal without causing excessive wear to the blade tips. The abradable coating system includes columns of an abradable material. Thus, interference between the blades and the abradable coating system causes the individual columns to break off at the base. This abrasion mechanism may reduce blade wear and spalling of the coating system when compared to conventional coatings.
    Type: Application
    Filed: August 1, 2006
    Publication date: June 11, 2009
    Inventor: David B. Allen
  • Publication number: 20090123722
    Abstract: The invention relates to a coating system (2) for a component (1) which comprises a porous layer (3) and an abradable layer (4) on the porous layer (3). Further the invention relates to an assembly of two components (1) which are relatively movable to each other and form a gap in between. One component (1) is provided with a coating system (2) and the other component (1) is in sliding contact with the coating system (2).
    Type: Application
    Filed: November 8, 2007
    Publication date: May 14, 2009
    Inventors: David B. Allen, Eckart Schumann, Ramesh Subramanian
  • Patent number: 7527472
    Abstract: A conformal seal (20) for sealing air flow between a cooling airflow path and a hot gas flow path within a combustion turbine engine. The conformal seal (20) may be fitted within cooperating side slots of adjacent vane segments (10) within the combustion turbine engine. The conformal seal (20) may include an elongated metallic substrate (22, 40) forming an upper surface and a lower surface. A conformal coating (26, 44) may be deposited over one or both surfaces of the substrate (22, 40). The conformal coating (26, 44) may be deposited to a depth so that a point contact between the conformal coating (26, 44) and respective interior walls of the side slots wears the conformal coating (26, 44) to establish surface area contact there between. The surface area contact improves a sealing function between the conformal coating (26, 44) and the respective interior walls during operation of the combustion turbine engine.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: May 5, 2009
    Assignee: Siemens Energy, Inc.
    Inventor: David B. Allen
  • Publication number: 20090110954
    Abstract: A bimetallic bond layer (26, 28) for a thermal barrier coating or TBC (30) on a superalloy substrate (22) for a high temperature environment. An interlayer (26) is applied on the substrate. A bond coat (28) comprising a CoNiCrAlY or NiCoCrAlY alloy is applied on the interlayer. A ceramic TBC (30) such as 8YSZ is applied on the bond coat. The interlayer (26) is an alloy that is compatible with the substrate and the bond coat, and that blocks or delays diffusion of aluminum from the bond coat into the substrate at high operating temperatures. This preserves aluminum in the bond coat that maintains a beneficial alumina scale (29) between the bond coat and the TBC. This delays spalling of the TBC, and lengthens the coating and component life.
    Type: Application
    Filed: September 3, 2008
    Publication date: April 30, 2009
    Applicant: SIEMENS POWER GENERATION, INC.
    Inventors: David B. Allen, Andrew J. Burns, Ramesh Subramanian
  • Publication number: 20080166585
    Abstract: A method for welding to a superalloy material without causing cracking of the material. The method includes the steps of depositing a weld strip (18) of a weldable material onto a superalloy substrate material (12) using a spray deposition process (20) and then forming a weldment (26) to the weld strip. None or a controlled amount of the substrate material (12) is melted during the weld in order to maintain the concentration of strengthening elements in the local melt within a zone of weldability. The spray deposition process may be a thermal process such as HVOF or a cold spray process. A groove (16) may be formed in a surface (10) of the superalloy substrate material to receive the weld strip. A diffusion heat treatment step may be used to improve adhesion between the weld strip and the superalloy material.
    Type: Application
    Filed: January 4, 2007
    Publication date: July 10, 2008
    Inventors: David B. Allen, Allister W. James, David W. Hunt
  • Publication number: 20080053107
    Abstract: One embodiment of a transition-to-turbine seal (300) comprises a first, flattened section (302) adapted to be received in a peripheral axial slot (320) of a transition (325), and a second, generally C-shaped section (301). The generally C-shaped section (301) comprises a flattened portion (305) near the first, flattened section (302), and a curved portion (306) extending to a free edge (307). A fiber metal strip component (309) may be attached to the flattened portion (305) to define a first engagement surface adapted to engage an upstream side (336) of an outer vane seal rail (337), and a second engagement surface 308, adjacent the free edge (307), provides an opposed wear surface adapted to engage a downstream side (338) of the outer vane seal rail (337). System embodiments also are described, in which such transition-to-turbine seal (300) is isolated from a hot gas path (350) by provision of a plurality of cooling apertures (327) in the transition (325).
    Type: Application
    Filed: August 3, 2006
    Publication date: March 6, 2008
    Inventors: Adam J. Weaver, Raymond S. Nordlund, David B. Allen, Daniel O. Davies
  • Publication number: 20080050236
    Abstract: A conformal seal (20) for sealing air flow between a cooling airflow path and a hot gas flow path within a combustion turbine engine. The conformal seal (20) may be fitted within cooperating side slots of adjacent vane segments (10) within the combustion turbine engine. The conformal seal (20) may include an elongated metallic substrate (22, 40) forming an upper surface and a lower surface. A conformal coating (26, 44) may be deposited over one or both surfaces of the substrate (22, 40). The conformal coating (26, 44) may be deposited to a depth so that a point contact between the conformal coating (26, 44) and respective interior walls of the side slots wears the conformal coating (26, 44) to establish surface area contact there between. The surface area contact improves a sealing function between the conformal coating (26, 44) and the respective interior walls during operation of the combustion turbine engine.
    Type: Application
    Filed: August 24, 2006
    Publication date: February 28, 2008
    Inventor: David B. Allen
  • Publication number: 20080044278
    Abstract: Aspects of the invention are directed to a system for improving engine performance by reducing vane tip clearances in the compressor section of a turbine engine. According to aspects of the invention, an abrasive material can be attached to a rotor disc. Thus, if a vane tip contacts the rotor disc during engine operation, the vane tip is worn away by the abrasive material. The system can reduce the risk of substantial component damage resulting from a vane tip rubbing event. The abrasive material can be provided in the form of an insert that can be removably attached to the rotor disc. Thus, the insert can be readily removed and replaced when necessary.
    Type: Application
    Filed: August 15, 2006
    Publication date: February 21, 2008
    Inventors: Hubertus E. Paprotna, David B. Allen, Oran L. Bertsch
  • Patent number: 6946208
    Abstract: An abradable thermal barrier coating material (10) formed of a highly defective fluorite ceramic matrix (16) having a desired degree of porosity (18) created in part by the addition of a fugitive material (19). The ceramic material has a concentration of a stabilizer sufficiently high that the oxygen vacancies created by the stabilizer interact within the matrix to form multi-vacancies, thereby improving the sintering resistance of the material. Such a concentration of stabilizer results in a material that is softer than prior art materials having lower concentrations of stabilizer, and that will be more resistive to sintering than prior art materials. Embodiments include a fluorite matrix of zirconia stabilized by at least 30 wt. % yttria, or stabilized by at least 30 wt. % ytterbia, and with porosity of 10-40%. In one embodiment, a metallic gas turbine seal ring segment is coated with a bond coat layer, then with a layer of porous 8 wt. % YSZ material, and finally with a layer of 33 mole % YbSZ (61.3 wt.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: September 20, 2005
    Assignee: Siemens Westinghouse Power Corporation
    Inventors: Ramesh Subramanian, David B. Allen
  • Patent number: 6835465
    Abstract: A device operable in a temperature environment in excess of about 1000° C. is provided. The device comprises a substrate and a ceramic thermal barrier layer deposited on at least a portion of the substrate. The layer is formed with a ternary or pseudoternary oxide having a pyrochlore or perovskite structure and a fugative material and having pores or other voluminous defects. The thermal barrier layer advantageously is abradable.
    Type: Grant
    Filed: May 13, 2002
    Date of Patent: December 28, 2004
    Assignee: Siemens Westinghouse Power Corporation
    Inventors: David B. Allen, Ramesh Subramanian, Wolfram Beele
  • Patent number: 6696176
    Abstract: A fusion weldable superalloy containing 0.005-0.5 wt. % scandium. In one embodiment, the superalloy may have a composition similar to IN-939 alloy, but having added scandium and having only 0.005-0.040 wt. % zirconium. A gas turbine component may be formed by an investment casting of such a scandium-containing superalloy, and may include a fusion weld repaired area. A scandium-containing nickel-based superalloy coated with an MCrAlY bond coat will have improved cyclic oxidation resistance due to the sulfur-gettering effect of the scandium.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: February 24, 2004
    Assignee: Siemens Westinghouse Power Corporation
    Inventors: David B. Allen, Gregg P. Wagner, Brij B. Seth
  • Publication number: 20030211354
    Abstract: An abradable thermal barrier coating material (10) formed of a highly defective fluorite ceramic matrix (16) having a desired degree of porosity (18) created in part by the addition of a fugitive material (19). The ceramic material has a concentration of a stabilizer sufficiently high that the oxygen vacancies created by the stabilizer interact within the matrix to form multi-vacancies, thereby improving the sintering resistance of the material. Such a concentration of stabilizer results in a material that is softer than prior art materials having lower concentrations of stabilizer, and that will be more resistive to sintering than prior art materials. Embodiments include a fluorite matrix of zirconia stabilized by at least 30 wt. % yttria, or stabilized by at least 30 wt. % ytterbia, and with porosity of 10-40%. In one embodiment, a metallic gas turbine seal ring segment is coated with a bond coat layer, then with a layer of porous 8 wt. % YSZ material, and finally with a layer of 33 mole % YbSZ (61.3 wt.
    Type: Application
    Filed: June 4, 2003
    Publication date: November 13, 2003
    Applicant: Siemens Westinghouse Power Corporation
    Inventors: Ramesh Subramanian, David B. Allen
  • Publication number: 20030170489
    Abstract: A fusion weldable superalloy containing 0.005-0.5 wt. % scandium. In one embodiment, the superalloy may have a composition similar to IN-939 alloy, but having added scandium and having only 0.005-0.040 wt. % zirconium. A gas turbine component may be formed by an investment casting of such a scandium-containing superalloy, and may include a fusion weld repaired area. A scandium-containing nickel-based superalloy coated with an MCrAlY bond coat will have improved cyclic oxidation resistance due to the sulfur-gettering effect of the scandium.
    Type: Application
    Filed: March 6, 2002
    Publication date: September 11, 2003
    Applicant: Siemens Westinghouse Power Corporation
    Inventors: David B. Allen, Gregg P. Wagner, Brij B. Seth