Abstract: This fuel assembly for a pressurized water nuclear reactor comprises fuel rods which are arranged at the nodes of a substantially regular network which has a polygonal outer contour, the fuel rods containing uranium which is enriched in isotope 235 and not containing any plutonium before the assembly is used in a reactor. The rods are distributed in at least a first central group which is constituted by fuel rods which have a first level of nuclear reactivity, and an outer peripheral layer of fuel rods which have a level/levels of nuclear reactivity which is/are strictly less than the first level of reactivity.
Abstract: The invention relates to an orbital apparatus (20) for machining of a revolution metallic wall, of the type comprising a fixed annular plate (30) coaxially mounted on a universal support and having a peripheral annular electric collector (35) and an annular plate (50) rotationally mobile and coaxially mounted on the fixed annular plate (30). The mobile annular plate (50) carries a set of electrical contacts (55) cooperating with the electrical collector (35), means (60) for rotationally driving the plate (50), means (70) for machining the metallic wall and pneumatic feeder means (80) to apply and maintain the machining means (70) on the metallic wall.
Abstract: A safety system for a nuclear plant includes a plurality of catalytic recombiner elements each triggering a recombination reaction with oxygen when hydrogen is entrained in an onflowing gas flow, so that reliable elimination of the hydrogen from the gas mixture is ensured with an especially high degree of operational safety even based on comparatively extreme conditions or scenarios of the aforementioned type. The recombiner elements and/or the flow paths each connecting two recombiner elements on the gas side are configured in such a way that a pressure pulse triggered in the gas medium by an ignition during the recombination reaction in a first recombiner element triggers a gas displacement process having a flow rate of at least 5 m/s in the onflow region of a second, adjacent recombiner element. A nuclear plant with a safety system is also provided.
Abstract: A method is provided for conditioning a waste solution obtained during the wet-chemical cleaning of conventional or nuclear plants and containing organic substances and metals in ionic form. At least a portion of the organic substance is degraded by electrochemical treatment or UV radiation of the waste solution, at least one metal precipitates by the addition of phosphoric acid and a resultant phosphate precipitate is removed from the waste solution.
Type:
Application
Filed:
July 27, 2010
Publication date:
November 18, 2010
Applicant:
AREVA NP GMBH
Inventors:
CHRISTIAN TOPF, SILVIA SCHUSS, FRANZ AMMANN
Abstract: A system and method of controlling a TCSC disposed on a high voltage line of an electrical transmission network. The system comprises: (a) a voltage measuring module; (b) a current measuring module; (c) a regulator, working in accordance with a non-linear control law to receive on its input the output signals from the two modules for measuring voltage and current, and a reference voltage corresponding to the fundamental of the voltage which is to obtained across the TCSC; (d) a module for extracting the control angle in accordance with an extraction algorithm; and (e) a module for controlling the thyristors (T1, T2) of the TCSC, and for receiving a zero current reference delivered by a phase-locked loop which gives the position of the current.
Abstract: The invention relates to a high-performance dielectric oil comprising approximately 75 to 95% by volume of a naphthenic oil and approximately 5 to 25% by volume of an ester oil, in particular a synthetic ester oil and more preferably an oil of the family of polyolesters. The high-performance dielectric oil may be used in high-voltage electrical equipment such as power, measurement, distribution or traction transformers, tap changers, bushings, distributors, oil-immersed circuit breakers, power capacitors, cables, etc.
Abstract: A container for a non-irradiated nuclear fuel assembly including a single casing for receiving at least one nuclear fuel assembly, the casing being formed from an elongate tubular shell, the shell including a metallic internal layer delimiting at least one individual housing for receiving a nuclear fuel assembly, and a metallic external layer surrounding the internal layer, the shell being filled between its internal layer and its external layer, and from lids for closing the or each housing at the longitudinal ends of the shell.
Abstract: The current transformer comprises at least two partial circuits (CBn) each comprising a Rogowski type winding (Cn), each of said the partial circuits being made in the form of an angular portion of a complete circuit (CB) which surrounds at least one primary conductor (10, 10A, 10B, 10C) of the transformer over 360°. The winding (Cn) of each partial circuit (CBn) is constituted by a go winding (Cn0) and by a return winding (Cn1) which extend over the angular extent (?n) of the partial circuit (CBn). For each partial circuit (CBn), the go and return windings are electrically connected in series, both having turns wound in the same direction so as to form a single winding (Cn) which presents a pair of adjacent electrical terminations (T1n, T2n) connected to an acquisition system (7, 7?).
Type:
Grant
Filed:
May 6, 2005
Date of Patent:
November 2, 2010
Assignee:
Areva T&D SA
Inventors:
Jean-Pierre Dupraz, Lionel Lucot, Olivier Chuniaud, Bernard Regnier
Abstract: A method for surface processing at least a portion of a component of zirconium or hafnium alloy, including at least one operation of nanostructuring a surface layer of the alloy so as to confer on the alloy over a thickness of at least 5 ?m a grain size which is less than or equal to 100 nm, the nanostructuring being carried out at a temperature which is less than or equal to that of the last thermal processing operation to which the component was previously subjected during its production. Component of zirconium or hafnium alloy processed in this manner.
Abstract: A method for determining the inner surface and an outer surface of a sample flake through the use of digital image photography wherein digital images of a sample flake first surface and second surface are compared to a known inner surface and known outer surface of a reference flake.
Type:
Grant
Filed:
May 26, 2006
Date of Patent:
October 26, 2010
Assignee:
Areva NP Inc.
Inventors:
Mihai G. M. Pop, John Carroll Griffith, William Edward Allmon, Brian Glenn Lockamon
Abstract: A fuel assembly for a boiling water reactor contains a plurality of fuel rods maintained laterally by spacers and surrounded by a fuel assembly case. The outer walls of a spacer are provided with projecting elements that maintain a minimum space between the outer surface of the spacer and the fuel assembly case, the opening span of a spacer being smaller than the internal width of the fuel assembly case. The fuel assembly is characterized in that the spacer is maintained in an off-center position by a force acting laterally thereon such that an external space located between an outer surface of the spacer associated with the outer surface of a central cell and the fuel assembly case is narrower than an internal gap opposite the external space and oriented towards the center or towards a control element disposed at the center.
Type:
Grant
Filed:
April 1, 2005
Date of Patent:
October 26, 2010
Assignee:
Areva NP GmbH
Inventors:
Peter Bucheit, Hans-Peter Fuchs, Matthias Rudolf
Abstract: A technical installation, especially a nuclear power plant, has a number of system components that are respectively supported by a number of beams, and a number of pressurized conduits. The technical installation is designed in such a way that secondary damage occurring in the surroundings of pressurized conduits are kept particularly low even if the pressurized conduits rupture. This is achieved in that at least one of the beams is embodied in a segmented manner in an area that is expected to be affected if a pressurized conduit ruptures, adjacent segments preferably being connected to each other via screw connections.
Abstract: A device for detecting and locating at least one electric discharge in equipment insulated by fluid contained in an electrically-conductive housing. The equipment includes a plurality of grounding lines connected between the housing and ground. The device includes a plurality of Rogowski coil type current detectors and a mechanism synchronously comparing signals delivered by the current detectors. The coil of each detector is placed around a respective one of the lines. Each detector delivers a signal representative of current flowing in the line, with occurrence of an electric discharge giving rise to a sudden variation in the current, and with electric discharge being located within an inside zone of the housing situated in proximity of the line that is surrounded by the detector that was first to deliver the sudden variation of current.
Abstract: A method involving periodic implementation, during the same operating cycle of the reactor, the method including following steps of: a) calculating, from measurements provided by sensors present in the reactor, the three-dimensional distribution of the local power in the core, b) simulating at least one accidental transient occurrence of power applied to the calculated three-dimensional distribution of local power, c) identifying, using thermomechanical calculations, at least one rod which is the most likely to be subject to a fracture of the cladding thereof during the simulated transient occurrence of power, and d) determining, using thermomechanical calculations on the rod identified, the value of the parameter which is representative of the operability of the reactor.
Type:
Application
Filed:
November 21, 2008
Publication date:
October 14, 2010
Applicant:
Areva NP
Inventors:
Gilles Andre Poyaud, Bruno Julien, Jean-Lucien Mourlevat
Abstract: A table comprising a base and a plurality of support members supported by the base is used to shape a mirror. The height of the plurality of support members is adjusted to form a predetermined shape. A mirror is placed over the plurality of support members, such that the mirror assumes the predetermined shape. A frame is then attached to the mirror such that when the mirror and frame are lifted off the table, the mirror substantially retains the predetermined shape.
Type:
Grant
Filed:
June 3, 2008
Date of Patent:
October 12, 2010
Assignee:
Areva Solar, Inc.
Inventors:
Philipp Hans Josef Schramek, Anthony John Roddom
Abstract: A method to determine corrective actions of a nuclear steam generator, having the steps of modeling of steam generator tube and deposit heat transfer characteristics by analytically deriving specific deposit characteristics and descriptive model parameters, wherein the modeling uses historical thermodynamic data for an operating plant under evaluation, identifying a set of one of preventive and corrective maintenance alternatives to accomplish steam generator deposit objectives, determining through the modeling a power production impact of each of the set of one of preventative and corrective maintenance alternatives to determine an economic cost for each of the set of preventative and corrective maintenance alternatives, and initiating a maintenance alternative with a lowest economic cost as compared to the maintenance evaluation alternatives with higher economic costs.
Type:
Grant
Filed:
November 5, 2009
Date of Patent:
October 12, 2010
Assignee:
Areva NP Inc.
Inventors:
Mihai G. M. Pop, John Carroll Griffith, Kent Colgan
Abstract: A method for conditioning a contaminated ion exchange resin includes mixing the contaminated ion exchange resin with water and at least partly breaking up the contaminated ion exchange resin into water-soluble components or fragments through the use of an oxidizing agent added to the water. A resulting aqueous solution is consolidated with a binder, optionally after concentration by evaporation of water.
Abstract: A method for conditioning a cleaning solution resulting from the wet chemical cleaning of a nuclear steam generator, includes electrolytically treating the cleaning solution and depositing radioactive metal nuclides contained in the cleaning solution on a cathode.
Abstract: A leak detecting apparatus for detecting flaws in a surface submerged in liquid is provided that includes a vacuum head for contacting the surface and forming a vacuum chamber filled with liquid between the surface and the vacuum head, the vacuum head including a multi-surface elastomer seal for contacting the surface; and a vacuum generator for pulling gas through a flaw in the surface into the vacuum head and to the gas separation chamber so as to displace the liquid from the gas separation chamber. A method for detecting flaws in a surface submerged in liquid is also provided.
Type:
Application
Filed:
March 26, 2010
Publication date:
September 30, 2010
Applicant:
AREVA NP INC
Inventors:
Gregory Jacob Denne, James Edwin McCann
Abstract: A motor operated valve diagnostic data acquisition system including: a motor operated valve assembly; a transmitter, the transmitter being permanently connected in a housing of a motor operated valve assembly; a receiver, the transmitter transmitting signals to the receiver via motor operated valve cables, the cables being existing motor operated valve cables; and electronic circuitry connected to the receiver, the electronic circuitry processing the signals received by the receiver.