Abstract: A repair device for underwater repair of a hole in a nuclear reactor part includes a holder (32), a cutting tool (22) held by the holder (32) and having at least one cutting tooth (70) for remachining an inner surface of the hole. The cutting tool (22) has a suction channel (44) extending into the cutting tool (22) between at least one inlet opening (46) and at least one outlet opening (48), a drive shaft (34) for rotating the cutting tool (22), the drive shaft (34) being held by the holder (32), and a suction tube (36) connected to the holder (32) and fluidly connected to the outlet opening (48) of the suction channel (44).

Abstract: A distance sensor unit is also provided. The distance sensor unit includes an array of distance sensors configured to identify surface irregularities deviating from an expected nominal geometry of a surface as the distance sensor unit is moved along the surface and a handheld housing configured for being gripped by an operator. The array of distance sensors is connected to the handheld housing. The distance sensor unit also includes at least one surface irregularity indicator configured for providing an alert to the operator as the distance sensor unit moves over one of the surface irregularities deviating from the expected nominal geometry of the surface.

Abstract: A gripper a fuel element, comprises a housing, an inner part arranged inside the housing, the inner part and the housing being displaceable relative to one another in an axial direction, with the inner part movable between a first end position and a second end position, a catch member movable between a gripping position and a release position, a gripper spring between the housing inner part counteracting movement of the inner part from the second end position, or an intermediate position (Z) between the first and second end position, to the first end position, and a damping system comprising a first and second connecting member for connecting the damping system to the housing, inner part and/or the fuel element loading machine, and a spring member arranged on the first and/or the second connecting member counteracting movement of the inner part from an intermediate position (Z) to the second end position.

Abstract: A method for treating waste water from the decontamination of a metal surface in a primary coolant circuit of a nuclear reactor comprises discharging a predetermined amount of an oxidation solution from the primary coolant circuit into a reduction zone connected to the primary coolant circuit and reacting the oxidation solution with a reducing agent to form a reaction solution that is freed of oxidizing agent, and passing the reaction solution over an ion-exchange resin in order to form a desalinated solution, and returning the desalinated solution to the primary coolant and/or disposing of the desalinated solution. A waste water treatment apparatus for carrying out the method is also provided.

Abstract: An absorber cluster for a nuclear reactor includes at least a first absorber assembly and a second absorber assembly. Each absorber assembly respectively comprises neutron absorbing elements. Absorber elements of each of the first absorber assembly and the second absorber assembly are made from the same material or the same combination of materials selected from the group of neutron absorbing materials consisting of a first europium hafnate, a second europium hafnate, a first samarium hafnate, a second samarium hafnate, hafnium carbide, and samarium hexaboride. The first europium hafnate and the second europium hafnate have different compositions. The first samarium hafnate and the second samarium hafnate have different compositions. The absorber elements of the first absorber assembly have a cross-sectional structure different to that of the absorber elements of the second absorber assembly.

Abstract: A method for sealing an opening extending radially from an outer circumferential surface to an inner circumferential surface of a tubular object in a nuclear power plant includes inserting a stopper from outside of the outer circumferential surface through the opening into the tubular object; and actuating a fastener from the outside of the circumferential surface to force the stopper radially outward to seal the opening. A mechanical seal assembly for plugging an opening in a tubular object by contacting an inner circumferential surface of the tubular object includes a stopper configured for insertion into an interior of the tubular object for plugging the opening. The stopper includes a surface configured for matching the inner circumferential surface of the tubular object.

Abstract: A method of producing a nuclear fuel product includes the steps of providing a core comprising aluminium and low-enriched uranium; and sealing said core in a cladding. The low-enriched uranium has a proportion of U235 below 20 wt %. The step of providing the core including melting low-enriched uranium and aluminium in a furnace to form a melt of uranium-aluminium alloy, producing a powder from the melt of uranium-aluminium alloy, and cold-spraying the powder on a surface of the cladding.

Abstract: A dry FCVS for a nuclear reactor containment is provided. The dry FCVS includes a housing and a round and/or elongated aerosol filter inside the housing for removing contaminant aerosols from gas passing through the housing during venting of the containment. The housing includes at least one inlet portion configured for directing gas into the aerosol filter during the venting of the containment and an outlet portion for gas filtered by the aerosol filter during the venting of the containment. The dry filtered containment venting system is arranged and configured such that when a flow of gas through the outlet portion is closed off at least one of convective, radiant and conductive heat transfer removes decay heat of aerosols captured in the aerosol filter.

Abstract: The invention provides a sintered rare earth metal oxide target for producing a radioisotope in an instrumentation tube of a nuclear power reactor, wherein the sintered target has a density of at least 90 percent of the theoretical density, and wherein the sintered target contains chromium in an amount of from 500 to 2000 ?g/g, and Mg and/or Ca in an amount of from 1000 to 6000 ?g/g. The sintered target is prepared by providing a rare earth metal oxide powder, blending the rare earth metal oxide powder with chromium oxide, dry granulating and consolidating the powder in a mold to form a spheroidal green body, and sintering the green body in solid phase to form a spheroidal ytterbia target.

Abstract: A catalytic recombiner and filter apparatus is especially suited for placement in a containment of a nuclear reactor. The apparatus has a natural convection flow duct with a number of catalytic elements for recombining hydrogen and oxygen contained in a gas flow through the flow duct. The catalytic recombiner and filter apparatus provides for reliable hydrogen reduction and iodine filtering for a gas flow even for a comparatively long period of operation. The catalytic recombiner and filter apparatus includes a number of adsorber elements with iodine adsorbing surfaces and with macroscopic flow channels in between. The iodine adsorbing surfaces are flown over by the gas flow, and the adsorber elements are arranged, when in use, downstream of the catalytic elements in a direction of the gas flow.

Abstract: A method for inspecting a metal surface (12) includes providing a first laser source (14) that is arranged to generate a first laser beam having a first wavelength comprised between 1000 nm and 1100 nm and a power higher than 1 W; providing a second laser source (16) that is arranged to generate a second laser beam having a second wavelength comprised between 1500 nm and 1800 nm and a power higher than 1 W; activating one of the first and second laser sources and transmitting the first or second laser beam to the entrance (22) of an optic (18); scanning the metal surface (12) with the laser beam projected by the optic; and acquiring at least one image of the infrared radiation emitted by the metal surface (12).

Abstract: A nuclear facility includes a fuel element pool which is filled with a cooling liquid. A fuel element rack, which is disposed in the fuel element pool, includes compartments for receiving fuel elements. The fuel elements received in the compartments are in direct contact with the cooling liquid in the fuel element pool. At least one cooling element is disposed in one of the compartments instead of a fuel element. The cooling element acts as a heat exchanger through which a coolant can flow, the cooling element is connected into a cooling circuit and the cooling element is immersed in the cooling liquid.

Abstract: A method of producing radionuclides from irradiation targets in a nuclear reactor uses at least one instrumentation tube system of a commercial nuclear reactor. Irradiation targets and dummy targets are inserted into an instrumentation finger and the irradiation targets are activated by exposing them to neutron flux in the nuclear reactor core to form a radionuclide. The dummy targets hold the irradiation targets at a predetermined axial position in the reactor core corresponding to a pre-calculated neutron flux density sufficient for converting the irradiation targets to the radionuclide. Separating the dummy targets from the activated irradiation targets includes exposure to a magnetic field to retain either the dummy targets or the activated irradiation targets in the instrumentation tube system and release the other one of the activated irradiation target or the dummy target from the instrumentation tube system. An apparatus adapted to the above method is also provided.

Abstract: A method for inspecting a nuclear reactor part includes placing an optical sensor (38) in front of the part to be inspected using a carrier (40); acquiring at least a first image of at least a reference portion of the part using the optical sensor (38), the or each first image being taken with a first magnification; reconstituting a three-dimensional model of said reference portion of the part using the or each first acquired image; calculating the position of an area to be inspected relative to the optical sensor (38) using the three-dimensional model; acquiring at least a second image of the area to be inspected using the optical sensor (38), the or each second image of the area to be inspected being taken with a second magnification higher than the first magnification.

Abstract: The invention provides a method of preparing irradiation targets for radioisotope production in instrumentation tubes of a nuclear power reactor, the method comprising the steps of: providing a powder consisting of an oxide of a rare earth metal having a purity of greater than 99% and, optionally, an organic binder; pelletizing the powder and optionally the organic binder to form a substantially spherical green body having a diameter of from between 1 to 10 mm; and sintering the spherical green body in solid phase at a temperature of at least 70 percent of a solidus temperature of the rare earth metal oxide powder and for a time sufficient to form a round sintered rare earth metal oxide target having a sintered density of at least 80 percent of the theoretical density.

Abstract: A sample container, sampling system and operating methods permit representative sampling from a liquid phase or boiling liquid, a gaseous phase, a containment sump, containment atmosphere, or condensation chamber of a nuclear power plant following a severe accident. A sample container obtaining an environmental sample includes an outer chamber surrounded by an outer container wall, being directly fluidically connected to the environment through a passage opening in the outer container wall and being fillable with a liquid at least in a base region. An inner chamber surrounded by an inner container wall is fluidically connected to the base region through a passage opening in the inner container wall, has connections for sampling and conveyor medium lines and is otherwise pressure and media tightly sealed from the environment. A pneumatically or hydraulically actuatable closure device for the passage opening between the outer and inner chambers has an actuation medium line connection.

Abstract: A method for detecting a defect on a surface (12) by multidirectional lighting includes acquiring a plurality of images of the surface (12) using an optical device (14) having an optical axis, each image being acquired with a lighting of the surface along a lighting direction (E, E?) given for each point of the surface (12) and an optical direction (O), the images being acquired with different lighting directions (E, E?) or different combinations and/or with different optical directions (O); for each point, calculating a plurality of parameters, the parameters including coefficients of an equation characterizing the response of said point of the surface as a function of the lighting direction (E, E?) and an observation direction (B, B?); and deducing from the calculated parameters whether the surface (12) has a defect at said point.

Abstract: A method for a multielement analysis via neutron activation. The method includes generating fast neutrons with an energy in the range of 10 keV to 20 MeV and moderating the neutrons, irradiating the sample with the neutrons, and measuring the gamma radiation emitted by the irradiated sample using a detector to determine at least one element of the sample. The sample continuously irradiated in a non-pulsed fashion. The measurement is implemented during the irradiation. The determination of the at least one element includes an evaluation of the measured gamma radiation. The sample is subdivided into individual partitions and the measurement is implemented using a collimator. The evaluation includes a spatially resolved and energy-resolved determination of the neutron flux within the respective partition of the sample and calculation of energy-dependent photopeak efficiencies and neutron flux and neutron spectrum within a single partition of the sample by an approximation method.

Abstract: A method for filtering radiation on a CCD based camera inspection video, the method including: capturing video signals via the camera; converting the video signals to a plurality of digital video frames; identifying radiation bright spots, defined as xnoids, in a pixel of at least one of the frames, replacing the xnoids and surrounding pixels with corresponding pixels of another of the frames to create a filtered frame. A system for the inspection of a nuclear power plant comprising: a camera; and a computer, the computer configured to execute identifying xnoids in a pixel of at least one digitized video frame and replacing the xnoids and surrounding pixels with corresponding pixels of another of the frames to create a filtered frame.

Abstract: A clamp sealing apparatus configured for preventing leakage from a defective region of a tube is provided. The clamp sealing apparatus includes a first clamping section and second clamping section tangentially connected to each other; and a seal held by the first and second clamping sections. Each of the first and second clamping sections includes a segment of a clamp body and a segment of a compression section. The clamp body and the compression section is configured for axially compressing the seal between the clamp body and the compression section such that the seal is pressed radially against an outer diameter surface of the tube onto the defective region by the axial compression to seal the defective region. A method of sealing a defective region of a tube to prevent fluid leakage through the defective region is also provided.