Abstract: A heat treatment method for desensitizing a nickel-based alloy with respect to environmentally-assisted cracking, the alloy having the following composition in percentages by weight: C?0.10%; Mn?0.5%; Si?0.5%; P?0.015%; S?0.015%; Ni?40%; Cr=12%-40%; Co?10%; Al?5%; Mo=0.1%-15%; Ti?5%; B?0.01%; Cu?5%; W=0.1%-15%; Nb=0-10%; Ta?10%; the balance being Fe, and inevitable impurities that result from processing, characterized in that the alloy is held at 950° C.-1160° C. in an atmosphere of pure hydrogen or containing at least 100 ppm of hydrogen mixed with an inert gas. A part made of a nickel-based alloy having the composition and that has been subjected to the heat treatment.

Abstract: A device of repairing a damaged area in an underwater wall region of a container or tank, in particular in the wall region of a tank of a nuclear reactor installation. The device has a guide system that can be mounted along a side wall, at a distance therefrom, and can be secured thereto. At least one first carriage is fitted onto the track of the guide system and movable in a longitudinal direction of the guide system. On the carriage there is displaceably mounted a receptacle for a repair overlay, which can be applied with an adhesive surface to the wall region containing the damaged area. At least one suction mount that is connected to a suction line is disposed on the first carriage and can be suctioned to the side wall.

Abstract: A computer implemented method for modelizing a nuclear reactor core, includes the steps of: partitioning the core in cubes to constitute nodes of a grid for computer implemented calculation, calculating neutron flux by using an iterative solving procedure of at least one eigensystem, the components of an iterant of the eigensystem corresponding either to a neutron flux, to a neutron outcurrent or to a neutron incurrent, for a respective cube to be calculated. The eigensystem iterative solving procedure includes a substep of conditioning the eigensystem into a spare eigensystem wherein the components of an iterant of the spare eigensystem correspond only either to neutron incurrents coming into the cubes or to neutron outcurrents coming from the cubes.

Abstract: A protective vehicle body of non-metallic material comprises an integrally molded base (1) providing a floor and a lower body wall (5), the lower body wall having a lip (6) extending outwardly therefrom; and an upper part (2) providing a roof and an upper body wall, a lower edge of the upper body wall fitting within the lip (6) and being demountably attached to the base (1). The body forms part of a vehicle additionally having a front portion (8) including a front axle and a rear portion (9) including a rear axle, the front and rear portions (8, 9) being attached to the vehicle body by attachment means that are severable from the vehicle body by a blast wave.

Abstract: The present invention provides a method and an apparatus for calibrating a first self-powered neutron detector for long term use in a nuclear reactor core with a second self-powered neutron detector, where the emitter material of the second self-powered neutron detector has a neutron absorption cross-section that is greater than the neutron absorption cross-section of the first emitter material for the first self-powered neutron detector.

Abstract: A shut-off device for a nuclear reactor component duct is provided that includes a plurality of elastic sealing rings, each radially expandable with respect to a common longitudinal axis between a retracted position at a distance from a wall of the duct and an expanded position for leaktight contact with the wall of the duct; a device provided for selectively moving the sealing rings between their retracted positions and their expanded positions; at least one member for locking in position the shut-off device in the duct to be shut off, distinct from the sealing rings, radially expandable with respect to the central axis between a retracted position in which the locking member is moved away from the wall of the duct and a locking position in which the locking member bears against the wall of the duct; a device provided for selectively moving the locking member between its retracted position and its locking position.

Abstract: The invention relates to a method of displaying and monitoring the profile of a weld bead (4), in which, placed inside the groove, there is an assembly (10) comprising, facing one another, an image acquisition means (11), a light source (12), the beam of which is directed towards said image acquisition means, and, between the image acquisition means and the light source, a mask (13); the optical axis of the image acquisition means (11) is oriented so as to be approximately parallel to the sidewalls (5, 6) of the groove (3); a light beam produced by the light source (12) is directed towards the mask (13) and the image acquisition means (11); a central shadow zone and a peripheral halo are formed by means of the light beam and the mask (13), said halo illuminating, approximately perpendicularly, the weld bead (4) and the sidewalls (5, 6); the profile of the weld bead (4) and the sidewalls (5, 6) are displayed on a display/monitoring means; and said assembly (10) is moved inside the groove (3) longitudinally and

Abstract: A securing device for a control rod in a nuclear facility contains a control rod drive and a drive housing enclosing the control rod drive and configured to pass through a reactor pressure wall. The securing device further has a reactor pressure wall connection piece arranged inwardly of the reactor pressure wall and connected to the reactor pressure wall. A device of this type is to be producible as cost-effectively as possible, is to perform its intended tasks reliably and is to be maintenance-free during operation. Accordingly, a number of connection elements are provided for this purpose between the reactor pressure wall connection piece and the drive housing. A respective connection element forms a form-locking connection to the drive housing and a form-locking connection to the reactor pressure wall connection piece.

Abstract: The nuclear fuel assembly means a group of nuclear fuel rods disposed in a substantially regular array together with a support skeleton (5), the assembly having: two nozzles; guide tubes interconnecting the nozzles; and spacer grids secured to the guide tubes for holding the rods. The assembly includes at least one support skeleton reinforcing device disposed between two successive spacer grids and secured to guide tubes. The reinforcing device is disposed inside the group of rods and presents a transverse extent that is smaller than the transverse extent of the array of nuclear fuel rods.

Abstract: A computer implemented method for modelizing a nuclear reactor core, including the steps of: partitioning the core in cubes to constitute nodes of a grid for computer implemented calculation, calculating neutron flux by using an iterative solving procedure of at least one eigensystem, the components of an iterant of the eigensystem corresponding either to a neutron flux, to a neutron outcurrent or to a neutron incurrent, for a respective cube to be calculated. The neutrons are sorted in a plurality of neutron energy groups, and the eigensystem iterative solving procedure includes a substep of conditioning the eigensystem into a restricted eigensystem corresponding to the eigensystem for a selection of some neutron energy groups.

Abstract: A turbine includes a plurality of stacked disks, each disk comprising an opening in the center of the disk, which forms a central flow chamber. The turbine further includes a first disk that is coupled to a bottom of the plurality of stacked disks. The first disk does not have an opening in the center like the stacked disks. There is a plurality of disk spacers positioned between one or more of the plurality of stacked disks, thereby creating flow channels between the disks. The flow channels extend from an outside perimeter of the stacked disks to the central flow chamber. A tapered armature is coupled to the first disk and positioned within the central flow chamber, and a fluid collection unit is in communication with the outside perimeter of the stacked disks.

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 device is provided for repairing a damaged location in an underwater region of a wall of a vessel or pool, in particular in the region of a wall of a pool of a nuclear reactor plant. The device includes a guiding system, which can be attached along a side wall at a distance therefrom and can be fixed thereto, for guiding a carriage which can be made to move in a longitudinal direction of the guiding system. Arranged on the carriage is a displaceably mounted holder for a repair support, which can be placed with an adhesive surface against the wall region containing the damaged location. With such a device, wall regions that are at a great depth and can only be accessed through narrow gaps can be repaired quickly and reliably.

Abstract: An isolating plant for isolating objects, in particular nuclear fuel pellets, fed in stacks, includes a feeding conveyor belt and an output conveyor belt, permitting a particularly reliable and interruption-free isolation of the fed objects simultaneously with a high processing speed. A delivery area, situated between the feeding conveyor belt and the output conveyor belt, includes a separating device driven by a pressure gas, in which the fed objects are separated from each other during operation of the plant by purposeful pressure-gas pulses in order to be delivered one by one to the output conveyor belt. A method for isolating nuclear fuel pellets is also provided.

Abstract: A process is provided for chemically decontaminating the surface of a metallic component. In a first treatment step, an oxide layer formed on the component by corrosion of the material of the component is detached from the surface of the component with a first aqueous treatment solution containing an organic decontamination acid. In a subsequent second treatment step, the surface which is at least partially freed of the oxide layer is treated with an aqueous solution containing an active component for removing particles which adhere to the surface. The active component is formed of at least one anionic surfactant from the group including sulphonic acids, phosphonic acids, carboxylic acids and salts of those acids.

Abstract: A filter is provided for cooling water conducting primary circuit of a nuclear power station. The power station contains a reactor container with a discharge opening for the cooling water that opens into the interior of the reactor container and being accessed when the power station is brought to a stop for an inspection shutdown. The filter contains a base carrier with an entrance, at least one filter cartridge held on the base carrier and is fluidically coupled to the entrance, and a fixing device that can be fixed to the discharge end such that the entrance couples fluidically to the discharge opening. In a method for filtering cooling water during the inspection shutdown a filter is fixed, by its fixing device, with its entrance in fluid connection with the discharge opening, the cooling water is circulated through the discharge opening, and the filter is removed from the discharge opening.

Abstract: A fuel assembly for a pressurized water nuclear reactor contains a multiplicity of fuel rods which are guided in a plurality of axially spaced spacers which in each case form a square grid, composed of grid webs, with a multiplicity of cells arranged in rows and columns. In each case one control rod guide tube is guided through a number of these cells. At least one spacer is configured to be mechanically stronger in a first partial region than in a second partial region. In this second partial region, the spacer is provided with at least one resisting element which protrudes into a flow sub-channel formed between the fuel rods and increases the flow resistance. The resisting element counteracts a reduction associated with the mechanically weaker configuration, in the flow resistance in the second partial region and in this manner effects a homogenization of the hydraulic behavior of a spacer which is mechanically inhomogeneous on account of the varying mechanical configuration.

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 method produces a welded connection between first and second components each having inner and outer sides interconnected by an end face. The first component has a ferritic basic body carrying a plating at the inside and having an end face with a buffer layer of Ni-based alloy. The second component is of austenitic material. The end faces of the components enclose a weld groove. An austenitic root, connecting the plating to the end face of the second component, is welded in the weld groove. An intermediate layer of a nickel alloy having at least 90% nickel is welded onto the root. The intermediate layer is connected to the end faces of the plating and the second component. A weld seam is then produced in the remaining weld groove using a nickel-based welding additive. A method for repairing a welded connection between first and second components is also provided.

Abstract: A dry conversion reactor for converting uranium hexafluoride to uranium dioxide, the dry conversion reactor including a gas-phase reaction segment and a fluidized bed segment, wherein at least one of the gas-phase reaction segment and the fluidized bed segment is a replaceable segment. A method for operating a dry conversion reactor utilizing a uranium hexafluoride to uranium dioxide conversion process, the method including replacing at least one conversion reactor segment.