Fuel Assembly Supports Patents (Class 376/362)
  • Patent number: 10699819
    Abstract: The invention relates to UF6 transport and process containers to store UF6 enriched up to 20 percent by weight 235U in amounts up to 1,500 kg U. The containers include a shell, which has an integral heat exchanger positioned between the exterior and interior surfaces/substrates of the shell. The integral heat exchanger is composed of metal passage voids to pass heat transport fluid. The shell forms an inner chamber, and a partition configuration is positioned within the inner chamber, extending longitudinally along the length of the container, to form a plurality of individual compartments within the inner chamber to store the UF6. The containers may be produced by additive manufacturing methods.
    Type: Grant
    Filed: May 6, 2019
    Date of Patent: June 30, 2020
    Assignee: Westinghouse Electric Company LLC
    Inventor: David L. Stucker
  • Patent number: 9053831
    Abstract: A fuel assembly 20 is constituted by combining a plurality of fuel rods 21, holding the fuel rods 21 by a plurality of support grids 22, and arranging a lower nozzle 24 and an upper nozzle 23 at opposite ends of the fuel rods 21. A shock-absorbing device 10 for a fuel assembly is fitted to the lower nozzle 24 and the upper nozzle 23. The shock-absorbing device 10 for a fuel assembly is constituted a nozzle support 12 fitted to a depression 24U of the lower nozzle 24 and a depression 23U of the upper nozzle 23, and a buffer 11 combined with the nozzle support 12, with stiffness thereof in a longitudinal direction of the fuel rods 21 being equal to or lower than that of the nozzle support 12.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: June 9, 2015
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Yoshiyuki Saito, Takeshi Yokoyama, Junichi Kishimoto
  • Patent number: 8483348
    Abstract: A hold-down spring unit for a top nozzle of a nuclear fuel assembly. The hold-down spring unit is coupled to the upper end of the top nozzle of the nuclear fuel assembly. The hold-down spring unit includes a first spring which provides a hold-down force upon the nuclear fuel assembly under start-up conditions or hot full power conditions of a nuclear reactor, and a second spring which provides an additional hold-down force upon the nuclear fuel assembly under start-up conditions of the nuclear reactor. The hold-down margin under start-up conditions or hot full power conditions is reduced, thus enhancing the mechanical and structural stability of the nuclear fuel assembly.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: July 9, 2013
    Assignee: Korea Nuclear Fuel Co., Ltd.
    Inventors: Joon Kyoo Park, Jin Seok Lee, Kyeong Lak Jeon, Jung Min Suh, Gi-Jun Gwon, Nam Gyu Park, Kyong Bo Eom, Jin Sun Kim, Dong Geun Ha, Kyoung Joo Kim
  • Publication number: 20130051509
    Abstract: In an initial core of a nuclear reactor, a plurality of water regions having a square cross section for occupying a cross sectional area capable of disposing four fuel assemblies are formed. No fuel assemblies are loaded in these water regions. In the initial core, each fuel assembly is supported by fuel supports. A pressure loss of a first orifice installed in a cooling water supply passage formed in first fuel supports disposed in a central portion of the initial core is larger than that of a second orifice installed in a cooling water supply passage formed in second fuel supports disposed in a peripheral portion surrounding the central portion. Each water region is formed right above a part of the first fuel supports disposed in the central portion. The control rod operation in the nuclear reactor can be simplified by action of cooling water in the water regions.
    Type: Application
    Filed: August 24, 2012
    Publication date: February 28, 2013
    Applicant: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Takeshi Mitsuyasu, Motoo Aoyama, Naoyuki Nakadozono, Kazuya Ishii
  • Patent number: 8355481
    Abstract: Provided is a sliding support and a system using the sliding support unit. The sliding support unit may include a fulcrum capture configured to attach to a support flange, a fulcrum support configured to attach to the fulcrum capture, and a baseplate block configured to support the fulcrum support. The system using the sliding support unit may include a pressure vessel, a pedestal bracket, and a plurality of sliding support units.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: January 15, 2013
    Assignee: GE-Hitachi Nuclear Energy Americas LLC
    Inventors: Michael R. Breach, David J. Keck, Gerald A. Deaver
  • Patent number: 8229055
    Abstract: The present invention relates to a top nozzle for a nuclear fuel assembly that has a two-stage elastic section such that a pushing force against the axial movement of the nuclear fuel assembly under normal conditions is optimized and at the same time a suppressing force against a drastic uplifting force of the nuclear fuel assembly under transient conditions is strengthened, and that lowers the elastic coefficients of the springs operating under normal conditions more than those of existing coil springs, thereby providing an optimal pushing force against the nuclear fuel assembly.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: July 24, 2012
    Assignee: Korea Nuclear Fuel Co., Ltd.
    Inventors: Joon-kyoo Park, Joon-hyung Choi, Kyu-Tae Kim, Jung-min Suh, Shin-ho Lee, Nam-gyu Park, Kyong-bo Eom, Jin-sun Kim, Jin-seok Lee, Seong-ki Lee
  • Patent number: 8208597
    Abstract: A nuclear reactor fuel bundle confinement system including: a fuel bundle with an upper tie plate; a channel enclosing the fuel bundle; a handle for the fuel bundle extending above the fuel bundle; an upper fuel particle barrier positioned over the upper tie plate and above the fuel rods, wherein the fuel particle barrier has a permeable panel at least co-extensive with an open area of the upper tie plate; a slot in the permeable panel through which passes the handle, and a closure device on the fuel particle barrier having a closed position which covers the slot and an open position that leaves the slot open; a lower fuel particle barrier positioned over the lower tie plate and below the fuel rods, wherein the lower portion of the fuel bundle assembly is grasped by the lower fuel particle barrier.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: June 26, 2012
    Assignee: Global Nuclear Fuel - Americas, LLC
    Inventors: Paul Everett Cantonwine, Andrew K. Langston, Charles B. Patterson, Jr., Johnny R. Skipper, Alexander Michael Hay, Carlton Wayne Clark, David Grey Smith
  • Publication number: 20110311015
    Abstract: An annulus spacer for a fuel channel assembly of a nuclear reactor. The fuel channel assembly includes a calandria tube and a pressure tube positioned at least partially within the calandria tube. The annulus spacer includes a garter spring configured to surround a portion of the pressure tube to maintain a gap between the calandria tube and the pressure tube. The garter spring includes a first end and a second end. The annulus spacer also includes a connector coupled to the first end and the second end of the garter spring. The connector allows movement of the annulus spacer when the pressure tube moves relative to the calandria tube during thermal cycles of the fuel channel assembly. The annulus spacer further includes a girdle wire positioned substantially within the garter spring and configured to form a loop around the pressure tube.
    Type: Application
    Filed: March 11, 2011
    Publication date: December 22, 2011
    Inventors: Reza Ziaei, Jan Frantisek Slavik, Gordon Rife, Marcia Helen Sanderson, Jean-Claude Stranart, Andre Roger Gagnon, Donald Ray Metzger
  • Patent number: 8027424
    Abstract: A fuel assembly for a boiling-water reactor has a water channel and a fuel assembly base, made from a sieve plate and a frame section enclosing the same. The water channel supports a plug with a bore running therethrough, at the lower end thereof, to which the fuel assembly base is fixed. The fuel assembly further comprises an opening through the sieve plate, a skirt, formed on the underside of the plug, surrounding the bore, extending into the opening in the sieve plate, a bush, provided with a first and a second longitudinal section, whereby the first longitudinal section extends from the underside of the sieve plate into the opening in a rotationally-fixed manner and a radial shoulder is provided between the two sections which contacts the underside of the sieve plate. A threaded section of a screw extends through the bush which engages in a thread in the bore in the plug.
    Type: Grant
    Filed: March 3, 2005
    Date of Patent: September 27, 2011
    Assignee: Areva NP GmbH
    Inventors: Michael Liebler-Ranzus, Erhard Friedrich
  • Patent number: 7822165
    Abstract: A debris filter bottom nozzle for a nuclear fuel assembly having a support skirt and a top plate. The top nozzle plate has defined therethrough a plurality of flow holes. The axial bore through each flow hole is contoured as a venture. Preferably, the venturi is formed with a double chamfered inlet.
    Type: Grant
    Filed: January 5, 2004
    Date of Patent: October 26, 2010
    Assignee: Westinghouse Electric Co LLC
    Inventors: Kirkland D. Broach, Carter E. Lunde, Phillip L. Hazlett
  • Publication number: 20100128833
    Abstract: A reactor core, comprising: an outermost region; a core region surrounded by said outermost region; a plurality of fuel support members, each of which is disposed at a lower end portion of said outermost region and said core region; and a plurality of fuel assemblies loaded in said outermost region and said core region and supported by said fuel support members, wherein a plurality of fuel assemblies disposed in said core region include a plurality of first fuel assemblies, each of which is inserted into a first coolant passage which is formed in said fuel support member and has a first resistor having an opening, and a plurality of second fuel assemblies, each of which is individually inserted into each of second coolant passage which is formed in said fuel support member and has a second resistor having an opening and a larger pressure loss than that of said first resistor; and, four fuel assemblies, each of which is adjacent to each of four lateral sides of each of a plurality of first fuel assemblies,
    Type: Application
    Filed: November 24, 2009
    Publication date: May 27, 2010
    Inventors: Takeshi Mitsuyasu, Motoo Aoyama, Kazuya Ishii, Masao Chaki
  • Patent number: 7672418
    Abstract: Control rod guide tubes for a nuclear reactor having a body with an axial length that defines a lower end portion and an upper end portion and a cavity within a substantial length of the body. Orifices are included at the upper and lower end portions of the body. A control rod chamber is located within the cavity and is configured for receiving a control rod. A plurality of ports is coupled to the cavity and is positioned at a substantial length from the upper end portion of the body. Also included are at least two flow channels within the cavity that extend a substantial portion of the axial length of the body. Each flow channel is fluidly coupled to one or more of the ports for receiving fluid flow from outside the body and an outlet proximate to the upper end portion of the body for providing the received fluid flow.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: March 2, 2010
    Assignee: Global Nuclear Fuel-Americas, LLC
    Inventors: Birol Aktas, Carlton W. Clark, William Earl Russell, II
  • Publication number: 20090296875
    Abstract: A fuel support for a nuclear reactor may include: a plurality of fuel support apertures, each fuel support aperture dimensioned for receiving a lower tie plate of a fuel assembly; and a plurality of lumens, each lumen being coupled to a different fuel support aperture. At least one lumen may be configured for attenuating a fluid flow differently than the fluid flow in at least one other of the lumen.
    Type: Application
    Filed: August 17, 2009
    Publication date: December 3, 2009
    Inventors: Birol AKTAS, Robert JAMES, Carlton W. CLARK, William Earl RUSSELL, II
  • Patent number: 7505547
    Abstract: Assemblies and methods for mounting a fuel assembly in a nuclear reactor include a fuel assembly includes fuel rods within the fuel assembly and a lower tie plate with a fuel assembly mating fixture. A fuel support includes a fuel support mating fixture that is constructed to selectively engage the fuel assembly mating fixture during installation of the fuel assembly onto the fuel support. The fuel support mating fixture and the fuel assembly mating fixture provides for a predefined orientation of the fuel assembly to the fuel support upon mating.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: March 17, 2009
    Assignee: Global Nuclear Fuel-Americas, LLC
    Inventors: William Earl Russell, II, Robert James, Carlton W. Clark
  • Publication number: 20090041174
    Abstract: A reactor core, comprising: an outermost region; a core region surrounded by said outermost region; a plurality of fuel support members, each of which is disposed at a lower end portion of said outermost region and said core region; and a plurality of fuel assemblies loaded in said outermost region and said core region and supported by said fuel support members, wherein a plurality of fuel assemblies disposed in said core region include a plurality of first fuel assemblies, each of which is inserted into a first coolant passage which is formed in said fuel support member and has a first resistor having an opening, and a plurality of second fuel assemblies, each of which is individually inserted into each of second coolant passage which is formed in said fuel support member and has a second resistor having an opening and a larger pressure loss than that of said first resistor; and, four fuel assemblies, each of which is adjacent to each of four lateral sides of each of a plurality of first fuel assemblies, inc
    Type: Application
    Filed: August 6, 2008
    Publication date: February 12, 2009
    Inventors: Takeshi MITSUYASU, Motoo AOYAMA, Kazuya ISHII, Masao CHAKI
  • Publication number: 20080152069
    Abstract: Fuel supports for a nuclear reactor and methods of modifying fluid flow in a reactor using a fuel support. The fuel supports include a plurality of lumens and a plurality of fuel support apertures with each fuel support aperture being dimensioned for receiving a lower tie plate of a fuel assembly. Each lumen is fluidly coupled to a different fuel support aperture. At least one lumen is configured for attenuating a fluid flow differently than the fluid flow in at least one other of the lumen.
    Type: Application
    Filed: December 22, 2006
    Publication date: June 26, 2008
    Inventors: Birol Aktas, Robert James, Carlton W. Clark, William Earl Russell
  • Publication number: 20080152068
    Abstract: Control rod guide tubes for a nuclear reactor having a body with an axial length that defines a lower end portion and an upper end portion and a cavity within a substantial length of the body. Orifices are included at the upper and lower end portions of the body. A control rod chamber is located within the cavity and is configured for receiving a control rod. A plurality of ports is coupled to the cavity and is positioned at a substantial length from the upper end portion of the body. Also included are at least two flow channels within the cavity that extend a substantial portion of the axial length of the body. Each flow channel is fluidly coupled to one or more of the ports for receiving fluid flow from outside the body and an outlet proximate to the upper end portion of the body for providing the received fluid flow.
    Type: Application
    Filed: December 22, 2006
    Publication date: June 26, 2008
    Inventors: Birol Aktas, Carlton W. Clark, William Earl Russell
  • Patent number: 7346141
    Abstract: A device and technique for placing and moving a ferromagnetic element in an annulus between coaxially arranged cylindrical tubes. The device includes an electromagnetic ram moved along the interior of a cylindrical tube. The movable ferromagnetic element is magnetically coupled to the electromagnetic ram and moved by magnetic force to a location in the annulus defined by the tubes and magnetically coupled to the electromagnetic ram for movement in and removal from the annulus.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: March 18, 2008
    Assignee: Areva NP Inc.
    Inventors: Ron Payne, Christopher Plucker
  • Patent number: 6934350
    Abstract: In an embodiment of the present invention, the core of a nuclear reactor includes a plurality of fuel cells and a plurality of large control rods. Each large control rod is about two times the width of a conventional control rod and includes four control rod blades extending radially from a central portion and arranged at right angles to each other. The blades define four fuel bundle receiving channels. The core is configured so that the control rods are-arranged in a plurality of staggered rows with four fuel bundles in each receiving channel.
    Type: Grant
    Filed: June 20, 2000
    Date of Patent: August 23, 2005
    Assignee: General Electric Company
    Inventors: Roy C. Challberg, Larry E. Fennern, Russell M. Fawcett
  • Patent number: 6888912
    Abstract: The apparatus for positioning a fuel assembly (10) comprises, on a respective side of the core support plate (19) and the upper core plate (9) directed towards an endpiece (15, 14) of the fuel assembly (10) at least two projecting positioning pins (16, 22) adapted to engage in openings in the lower endpiece (15) or upper endpiece (14). Each of the positioning pins (16, 22) is fixed in a blind opening (24) comprising a threaded bore and a support surface perpendicular to the axis of the blind opening (24) and comprises a flange adapted to come into contact with the support surface when the positioning pin (16, 22) is screwed into the threaded bore. A gudgeon enables the positioning pin to be locked to secure it against unscrewing. The invention also relates to a process and apparatus for replacing damaged positioning pins on the core support plate (19) or on the upper core plate (9).
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: May 3, 2005
    Assignee: Framatome ANP
    Inventors: Gilles Morel, Daniel Grypczynski, S├ębastien Joly
  • Patent number: 6813327
    Abstract: A core plate assembly for a nuclear reactor includes a plurality of support beams, a flat plate positioned on top of the support beams, a plurality of control rod guide tube openings arranged in staggered rows, and a plurality of fuel supports extending through the flat plate. Each guide tube opening has a cruciform shape defines four fuel bundle receiving areas. Each fuel support includes a coolant flow inlet, and a coolant flow outlet sized to receive a lower tie plate of a fuel bundle. The coolant flow inlet is offset from coolant flow outlet so that a centerline of the coolant flow inlet is parallel to a centerline of the coolant flow outlet. The coolant flow inlets are positioned adjacent a support beam, and the coolant flow outlets are positioned in a fuel bundle receiving area.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: November 2, 2004
    Assignee: General Electric Company
    Inventor: Roy C. Challberg
  • Publication number: 20040114704
    Abstract: The apparatus for positioning a fuel assembly (10) comprises, on a respective side of the core support plate (19) and the upper core plate (9) directed towards an endpiece (15, 14) of the fuel assembly (10) at least two projecting positioning pins (16, 22) adapted to engage in openings in the lower endpiece (15) or upper endpiece (14). Each of the positioning pins (16, 22) is fixed in a blind opening (24) comprising a threaded bore and a support surface perpendicular to the axis of the blind opening (24) and comprises a flange adapted to come into contact with the support surface when the positioning pin (16, 22) is screwed into the threaded bore. A gudgeon enables the positioning pin to be locked to secure it against unscrewing. The invention also relates to a process and apparatus for replacing damaged positioning pins on the core support plate (19) or on the upper core plate (9).
    Type: Application
    Filed: June 11, 2003
    Publication date: June 17, 2004
    Inventors: Gilles Morel, Daniel Grypczynski, Sebastien Joly
  • Patent number: 6351511
    Abstract: An apparatus for reinforcing weakened portions of the top guide assembly in a boiling water reactor. The repair apparatus includes a cruciform lattice segment which reinforces the damaged or weakened region of the top guide beam lattice. This cruciform lattice segment is held in place atop the existing top guide with specially designed straps. The cruciform lattice segment and associated straps are arranged so that a beam segment of the cruciform lattice segment bridges the weakened region in the cracked top guide. Thus, the bridging beam segment transmits loads across the weakened region of the top guide. The straps are designed to avoid interference with removal and installation of the fuel assemblies and the control rod blade which is inserted between the fuel assemblies.
    Type: Grant
    Filed: April 12, 1996
    Date of Patent: February 26, 2002
    Assignee: General Electric Company
    Inventors: Gerald Alan Deaver, James Walton Pyron, Anh Ngoc Nguyen
  • Patent number: 6097779
    Abstract: Fuel bundle and control rod assemblies for a nuclear reactor are described. In one embodiment of the apparatus, the nuclear reactor includes several conventional size fuel bundles and at least one large control rod. The large control rod includes four fuel bundle receiving channels, and each such channel is sized to receive four conventional size fuel bundles.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: August 1, 2000
    Assignee: General Electric Company
    Inventors: Roy C. Challberg, Larry E. Fennern, Russell M. Fawcett
  • Patent number: 5920603
    Abstract: A forged core plate fabricated from a single piece stainless steel forging is described. The plate has a substantially circular shape and penetrations are provided in the core plate to allow passage of control rod blades into the core and direct recirculation flow past the fuel assemblies. The penetrations are formed from machining "5 holes" per penetration. Particularly, each penetration includes a center through hole to allow passage of the control rod blade and control rod blade guide tube. The through hole has a smaller diameter at the plate top surface to provide a tighter fit to the outside diameter of the guide tube to maintain alignment and minimize flow leakage. The through hole is enlarged at the core plate bottom surface to allow clearance in order to improve the installation and removal of the guide tube. Each penetration also include four peripheral blind holes to direct the recirculation flow into the flow holes located on the sides of the guide tube.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: July 6, 1999
    Assignee: General Electric Company
    Inventors: Jack T. Matsumoto, Alex B. Fife
  • Patent number: 5892806
    Abstract: A spacer for maintaining a pressure tube in spaced relation with a caland tube of a nuclear reactor. The spacer comprising a split ring adapted to be disposed about the outer surface of said pressure tube. The ring has a central annular body portion with a raised bearing surface thereon adapted to contact the inner surface of said calandria tube and prevent contact between said outer surface and said inner surface. An annular land projecting from each side of said central body portion is adapted to receive a collar thereon effective create an interference fit between said ring and said pressure tube and thereby constrain axial movement of said spacer on said pressure tube. The spacer of the present invention maintains its location on the pressure tube and does not suffer the axial movement which characterizes some conventional spacers. The bearing surface can have a coating to reduce wear and heat transfer.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: April 6, 1999
    Assignee: Atomic Energy of Canada Limited/Energie Atomique du Canada Limitee
    Inventor: David A. Scott
  • Patent number: 5574760
    Abstract: In order to eliminate the need to weld, drill or otherwise machine a shroud structure which is used to surround a plurality of fuel assemblies in a nuclear reactor, a plurality of upper hanger rods interconnect a structure above the shroud to a support ring which is clamped about the upper periphery of the shroud. Lower hanger rods interconnect a lower edge or shoulder portion of the shroud with the support ring. Thus, through the upper and lower hanger rods and the support ring, the shroud can be supported within the RPV. The upper support ring is arranged to clamp the lower ends of the upper hanger rods against the upper outer peripheral portion of the shroud while the lower ends of the lower hanger rods are clamped against the lower peripheral wall portion of the shroud by a lower support ring.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: November 12, 1996
    Assignee: Combustion Engineering, Inc.
    Inventor: Bengt I. Baversten
  • Patent number: 5436946
    Abstract: Leaf-type springs are inserted into slots in an upper tie plate of a nuclear fuel assembly and bear against interior surfaces of the fuel channel to center the upper tie plate within the fuel channel. More robust similarly configured leaf springs are secured in slots in the upper tie plate and are cantilevered for bearing engagement through slots in the fuel assembly channel against the reactor top guide to bias the fuel assemblies toward the control rod. To mount each spring to the upper tie plate, the base of each leaf spring includes a central beam and a pair of outermost beams spaced from the central beam, all beams lying in a common plane. Laterally outwardly directed tabs are provided on the lower ends of the outer beams. Stops are provided intermediate the ends of the outer beams. By inserting the unstressed, unloaded base of the springs into the slots, the outer beams are displaced inwardly into a stressed condition.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: July 25, 1995
    Assignee: General Electric Company
    Inventors: Michael V. Curulla, Eric B. Johansson, Carl R. Mefford, Jerry T. Spell, Robert B. Elkins, Jaime A. Zuloaga, Jr.
  • Patent number: 5416811
    Abstract: An upper end fitting for a nuclear fuel assembly that eliminates the problem of free standing fuel assemblies leaning out of range of the lead in provided when installing the reactor upper internals structure. The outer dimensions of each upper end fitting in the fuel assembly are larger than their respective spacer grids and lower end fittings such that the nominal gap between upper end fittings is approximately 0.025 inch.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: May 16, 1995
    Assignee: B&W Fuel Company
    Inventors: Douglas J. Attix, Samuel V. Pickerel, Jr.
  • Patent number: 5347560
    Abstract: In a fuel assembly, lower end pieces of fuel rods, guide tubes and coolant pipes, etc., are inserted and/or screwed into a base plate and secured against lifting by a bolt. In the case of fuel rods, in particular fuel rods which do not extend over the entire length of normal rods, the bolt is screwed onto connecting parts in such a way that a releasable bayonet closure is produced. In the case of coolant pipes of boiling water reactors, there is provided in particular a screw connection which is irreleasably secured against torsion by the bolt.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: September 13, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hans-Joachim Lippert, Werner Meier
  • Patent number: 5241570
    Abstract: In a boiling-water nuclear reactor, a core-control assembly comprises a control rod, a fuel support, a control-rod guide tube, a control-rod drive, and a control-rod-drive housing. The fuel support is welded to the control-rod guide tube. To remove the control-rod drive, the reactor vessel can be opened and the adjacent fuel bundles removed from the fuel support. Then the control-rod can be rotated after clearing the fuel support. The control rod is then rotated to decouple its bayonet connection to the control-rod drive. The control rod can then be lifted out of the reactor. This arrangement allows a control rod to be replaced without handling of the fuel support. In addition, the fuel support can be more securely installed since it does not need to be removed.
    Type: Grant
    Filed: June 8, 1992
    Date of Patent: August 31, 1993
    Assignee: General Electric Company
    Inventor: Roy C. Challberg
  • Patent number: 5141701
    Abstract: Bottom end fuel assembly reconstitution is permitted by elimination of weld of Inconel lower grid perimeter strip to stainless steel lower end fitting. Slots in 2 or 3 sides of L.E. Fitting capture ribbed sections of grid perimeter strip, locking screws hold L.E. Fitting in position on guide thimbles. Grids lip on perimeter strip is interlocked by sliding in L.E. Fitting groove.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: August 25, 1992
    Assignee: Combustion Engineering, Inc.
    Inventor: William J. Bryan
  • Patent number: 5132078
    Abstract: A diagrid for a nuclear reactor core, of the type with two disc-like plates, for a series of parallel chandelles, and a cylindrical shell fitted with heat-exchanging fluid input and output ducts. A forced fit between the edges of said plates (10,11) and said shell (12) consists of a thick welded joint. The upper ends of each of the chandelles (30) protrudes above the upper surface of the upper plate. The two ends of each of the chandelles are welded to the plates.
    Type: Grant
    Filed: July 18, 1989
    Date of Patent: July 21, 1992
    Assignee: Ansaldo S.p.A.
    Inventor: Giulio Cai
  • Patent number: 5047225
    Abstract: A carbonized composite foam having a density less than about 50 mg/cm.sup.3 and individual cell sizes no greater than about 1 .mu.m in diameter is described, and the process of making it.
    Type: Grant
    Filed: March 14, 1990
    Date of Patent: September 10, 1991
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Fung-Ming Kong
  • Patent number: 5024809
    Abstract: A nuclear fuel element for use in the core of a nuclear reactor is disclosed having an improved corrosion resistant cladding. The cladding is comprised of zirconium alloys containing in weight percent 0.5 to 2.0 percent tin, or 0.5 to 2.5 percent bismuth, or 0.5 to 2.5 percent bismuth and tin, and about 0.5 to 1.0 percent of a solute composed of a member selected from the group consisting of molybdenum, niobium, tellurium and mixtures thereof, and the balance zirconium. Composite claddings are disclosed having a surface layer of one of the corrosion resistant zirconium alloys metallurgically bonded to a Zircaloy alloy tube. Claddings may contain an inner barrier layer of a moderate purity zirconium metallurgically bonded on the inside surface of the cladding to provide protection from fission products and gaseous impurities generated by the enclosed nuclear fuel.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: June 18, 1991
    Assignee: General Electric Company
    Inventor: Dale F. Taylor
  • Patent number: 4904443
    Abstract: The control rod drive is removed from the top of the reactor. The control rod drive is attached at its upper end to the bottom end of the control rod drive guide tube. The control rod guide tube in turn couples at a rotationally locked bayonet fitting to the top of the control rod drive housing. Locking of the bayonet fitting occurs thru the orificed fuel support casting. The orificed fuel support casting, is locked from rotation at a pin located on the reactor core plate. The control rod guide tube in turn locks rotationally to the orificed fuel support casting. During refueling, the fuel bundles and the orificed fuel support casting are removed, freeing the control rod guide tube and its depending drive for rotation. Thereafter, a fitting captures the control rod guide tubes at coolant inflow apertures and rotates the guide tubes and the depending drives.
    Type: Grant
    Filed: June 2, 1988
    Date of Patent: February 27, 1990
    Assignee: General Electric Company
    Inventor: John C. Carruth
  • Patent number: 4876061
    Abstract: A pressurized water reactor of an advanced design comprises, in vertically spaced relationship, a lower barrel assembly having lower and upper core plates, an inner barrel assembly and an axially removable calandria assembly having a lower calandria plate. A plurality of rod guides are cantilever-mounted in parallel axial relationship within the inner barrel assembly and, specifically, are rigidly mounted at the lower ends thereof to the upper core plate. Axially extending sleeves are affixed to the upper ends of the rod guides and telescopingly receive therein generally cylindrical supports which are affixed to and depend downwardly from the lower calandria plate and define alignment axes for the respectively associated rod guides.
    Type: Grant
    Filed: August 24, 1988
    Date of Patent: October 24, 1989
    Assignee: Westinghouse Electric Corp.
    Inventors: Douglas E. Ekeroth, Luciano Veronesi
  • Patent number: 4859400
    Abstract: A nuclear reactor fuel core assembly comprises an array of sub-assemblies comprising a central zone of fuel/breeder sub-assemblies (20F) surrounded by an annular zone of shielding sub-assemblies (20S). The fuel/breeder sub-assemblies (20F) are flexibly mounted from the reactor diagrid top plate 26 while the shielding sub-assemblies (20S) are mounted as stiff cantilevers so as to provide resilient restraint against bow of the central sub-assemblies (20S) during reactor operation, the restraint being exerted via abutment pads (40) at the level of the tops of the sub-assemblies (20S, 20F). The central core sub-assemblies (20F) also have abutment pads (34) at a lower level to form a lower restraint plane at this level controlling sub-assembly bowing in the central core zone.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: August 22, 1989
    Assignee: National Nuclear Corporation Ltd.
    Inventor: Andrew F. Curzon
  • Patent number: 4756877
    Abstract: A core support system for a core barrel of a nuclear reactor, which core barrel has a bottom core support plate wherein the core support plate has apertures therethrough about the periphery thereof which communicate with recesses in engagement means for the core support plate, and keys inserted into the core support plate apertures and secured thereto with the lower section of the key extending into the recess of the engagement means. The method of installation enables alignment and securement of the core barrel in the pressure vessel without need for an assembler to enter the area between the core barrel support plate and the bottom of the vessel.
    Type: Grant
    Filed: November 6, 1985
    Date of Patent: July 12, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Luciano Veronesi, Stephen N. Tower
  • Patent number: 4755351
    Abstract: The leaf springs mounted in the upper nozzle of a prior art fuel assembly, which are compressed by the upper core plate to restrain the upward movement of the fuel assembly under the pressure of upwardly-flowing coolant, as dispensed with. Instead the fuel assembly is permitted to rise in a controlled manner into engagement with the upper core-support plate. The lower nozzle is provided with snubbers which engage, and exert low pressure, as required by the specifications governing a reactor, on the lower core plates when the fuel assembly is raised into engagement with the upper core plate by the force of the flowing coolant. In addition springs are provided between the pins extending from the upper and lower core plates and the walls of the holes in the upper and lower nozzles to suppress vibration under the transverse forces impressed by the flowing coolant.
    Type: Grant
    Filed: June 4, 1986
    Date of Patent: July 5, 1988
    Assignee: Westinghouse Electric Corp.
    Inventors: Frank J. Baloh, James A. Sparrow
  • Patent number: 4678631
    Abstract: A BWR fuel assembly having an array of spaced fuel rods, an outer tubular flow channel surrounding the fuel rods so as to direct flow of coolant/moderator fluid along the fuel rods, and a hollow central water cross extending through the outer flow channel and composed of respective pairs of spaced apart sheet members interconnected together at their outer and inner ends so as to define an open inner cruciform flow channel for subcooled moderator fluid flow through the fuel assembly and to the outer channel so as to divide the array of fuel rods into a plurality of fuel rod subassemblies, includes features which improve structural and hydraulic characteristics as well as CHF characteristics. The features which improve structural and hydraulic characteristics relates to closures in the form of perforated plates connected across the bottom and top ends of the sheet members of the water cross.
    Type: Grant
    Filed: May 2, 1985
    Date of Patent: July 7, 1987
    Assignee: Westinghouse Electric Corp.
    Inventor: Rusi P. Taleyarkhan
  • Patent number: 4673548
    Abstract: A thermal barrier/core support for the fuel core of a nuclear reactor having a metallic cylinder secured to the reactor vessel liner and surrounded by fibrous insulation material. A top cap is secured to the upper end of the metallic cylinder that locates and orients a cover block and post seat. Under normal operating conditions, the metallic cylinder supports the entire load exerted by its associated fuel core post. Disposed within the metallic cylinder is a column of ceramic material, the height of which is less than that of the metallic cylinder, and thus is not normally load bearing. In the event of a temperature excursion beyond the design limits of the metallic cylinder and resulting in deformation of the cylinder, the ceramic column will abut the top cap to support the fuel core post.
    Type: Grant
    Filed: August 31, 1984
    Date of Patent: June 16, 1987
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: William S. Betts, Jr., J. Larry Pickering, William E. Black
  • Patent number: 4615862
    Abstract: A nuclear reactor in which the bottom nozzle of each fuel assembly is a casting having leg-like pins which are cast as part of the bottom nozzle. The pins extend from the corners of the bottom nozzle of each fuel assembly. The transverse cross section of each pin has the shape of a circular sector whose arc depends on the number of apeces of the bottom nozzle, typically 90.degree. for a square nozzle and 120.degree. for a hexagonal nozzle. The fuel assemblies are mutually nested side-by-side so that a group of contiguous pins extends from each region where corners of fuel elements converge. The sides of the pins of each group are in engagement so that the pins of the group form a continuous circularly cylindrical surface. The core support plate has a plurality of holes. The boundaries of the holes are circular cylinders. Each group of pins extend into a hole in the core support plate.
    Type: Grant
    Filed: December 21, 1983
    Date of Patent: October 7, 1986
    Assignee: Westinghouse Electric Corp.
    Inventor: Edgar A. Huckestein
  • Patent number: 4567015
    Abstract: The frame consists of a base and a plurality of square tubes which are secured to the base in upstanding manner. The base consists of rows of intersecting, inter-fitted and inter-welded metal strips which are disposed in mutually perpendicular groups. The tubes are arranged on the strips in a checkerboard fashion with two walls of each tube substantially flush with two parallel strips. In addition, the rows of tubes are offset to one group of metal strips so that the strips are disposed in planes coincident with the longitudinal axes of the tubes in order to support nuclear fuel elements thereon.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: January 28, 1986
    Assignee: Sulzer Brothers Limited
    Inventor: Ernst Bosshard
  • Patent number: 4563328
    Abstract: A nuclear reactor fuel assembly with two support plates and a holding rod connecting the two support plates rigidly with mutual spacing, the holding rod having a longitudinal axis passing through both support plates, and being held at one end in a lead-through in one of the two support plates, includes, in the lead-through, an elongated holding body for the holding rod rotatable about the longitudinal axis thereof, and displaceable in direction of the longitudinal axis thereof coaxially with the lead-through; the holding body being rigidly connectible by a rotation relative to the holding rod about the longitudinal axis thereof to an end of the holding rod and tightenable against a holding shoulder in the one support plate and detachable from the holding rod; and a spring element braced against the support plate and pressing the holding body elastically against the holding shoulder.
    Type: Grant
    Filed: October 25, 1983
    Date of Patent: January 7, 1986
    Assignee: Kraftwerk Union Aktiengesellschaft
    Inventor: Alexander Steinke
  • Patent number: 4534933
    Abstract: A nuclear reactor fuel assembly having an improved top nozzle subassembly with a hold-down device incorporated therewithin to prevent the force of the upward coolant flow from lifting the fuel assembly into damaging contact with the upper core support plate, while allowing for changes in fuel assembly length due to core-induced thermal expansion. The construction of the fuel assembly is such that its top surface can be placed in direct contact with the upper core plate. Thermal expansion of the components of the fuel assembly in the upward direction are accommodated within the top nozzle subassembly.
    Type: Grant
    Filed: October 17, 1983
    Date of Patent: August 13, 1985
    Assignee: Westinghouse Electric Corp.
    Inventors: Robert K. Gjertsen, Luciano Veronesi
  • Patent number: 4514358
    Abstract: A boiling water reactor fuel assembly is provided with an elongated, vertical stiffening device having four stiffening wings (4) which are each attached to a wall of the fuel box. Each stiffening wing has at least one vertically directed passageway for water. The stiffening device has a cruciform cross-section and is composed of four elongated members (6, 6', 6", 6'") of L-shaped cross-sections.
    Type: Grant
    Filed: March 23, 1984
    Date of Patent: April 30, 1985
    Assignee: AB ASEA-ATOM
    Inventors: Bo Borrman, Erik Hellman, Bengt Ode, Aart van Santen
  • Patent number: 4474398
    Abstract: The fuel assembly locking apparatus comprises a rotatable plate capable of simultaneously and positively engaging all four legs of the bottom nozzle of a fuel assembly for uniformly holding the fuel assembly while the spent fuel rods are pulled from the fuel assembly. The rotatable plate has four notched corners arranged to be rotated over a ledge on each leg of the bottom nozzle of the fuel assembly thereby preventing movement of the fuel assembly. The rotatable plate is also capable of being rotated 45.degree. so that the four corners of the plate are rotated clear of the legs of the bottom nozzle of the fuel assembly thereby allowing the fuel assembly to be placed on or removed from the locking apparatus. The locking apparatus is also provided with a torque actuator for remotely rotating the plate.
    Type: Grant
    Filed: June 26, 1981
    Date of Patent: October 2, 1984
    Assignee: Westinghouse Electric Corp.
    Inventors: Ralph W. Tolino, Charles E. Toler, Sr.
  • Patent number: 4457890
    Abstract: A liquid metal cooled nuclear reactor of the kind wherein a fuel assembly is supported on a diagrid and submerged in a pool of coolant. The diagrid comprises a plenum supported on a load bearing undershell and has an array of resilient spikes upstanding from the upper face of the plenum each for locating a fuel sub-assembly. The load of the fuel assembly is distributed over the upper face plate of the plenum and transmitted to the undershell by an array of strut members.
    Type: Grant
    Filed: February 6, 1981
    Date of Patent: July 3, 1984
    Assignee: National Nuclear Corporation
    Inventor: Donald Scott
  • Patent number: H177
    Abstract: A pool type nuclear fission reactor has a core, with a plurality of core elements and a redan which confines coolant as a hot pool at a first end of the core separated from a cold pool at a second end of the core by the redan. A fuel handling system for use with such reactors comprises a core element storage basket located outside of the redan in the cold pool. An access passage is formed in the redan with a gate for opening and closing the passage to maintain the temperature differential between the hot pool and the cold pool. A mechanism is provided for opening and closing the gate. A lifting arm is also provided for manipulating the fuel core elements through the access passage between the storage basket and the core when the redan gate is open.
    Type: Grant
    Filed: November 6, 1985
    Date of Patent: December 2, 1986
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: James G. Saiveau, William J. Kann, James P. Burelbach