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 boring assembly extends along a main axis and comprises a boring head comprising at least one first nozzle and at least one second nozzle The or each second nozzle is different from the or each first nozzle. The boring assembly includes a first delivery device configured to deliver a jet of abrasive-free water at a pressure comprised between 2000 bar and 4000 bar to the at least one first nozzle. The boring assembly includes a second delivery device configured to deliver a jet containing at least one abrasive material at a pressure comprised between 2000 bar and 6000 bar to the at least one second nozzle.

Abstract: A leakage testing device for testing leakage of a nuclear fuel assembly (18) by sipping. The device includes a collection assembly (32) that is configured to close an upper end (24A) of a cell (24) of a storage rack (22) for storing nuclear fuel assemblies discharged from a nuclear reactor (4). The closing prevents water contained in the cell from escaping via the upper end of the cell. The collection assembly is configured to collect products containing possible fission products released by a nuclear fuel assembly contained in the cell.

Abstract: A method for calculating a PCI margin associated with a loading pattern of a nuclear reactor including a core into which fuel assemblies are loaded according to the loading pattern is implemented by an electronic system. The fuel assemblies include fuel rods each including fuel pellets of nuclear fuel and a cladding surrounding the pellets. This method includes calculating a reference principal PCI margin for a reference loading pattern of the fuel assemblies in the core; calculating a reference secondary PCI margin for the reference pattern; calculating a modified secondary PCI margin for a modified loading pattern of the fuel assemblies in the core, and calculating a modified principal PCI margin for the modified pattern, depending on a comparison of the modified secondary PCI margin with the reference secondary PCI margin.

Abstract: A method for dismantling a steam generator or heat exchanger, such as found in nuclear power plants, which steam generator or heat exchanger includes a plurality of primary circuit tubes with a contaminated inner surface and wherein one or more tubes are sealed with a plug at both end is provided, the method comprising a) opening one or both ends of each sealed tube by creating an opening in or removing, the plug (13); b) introducing a viscous polymer to cure inside the tube wherein the polymer fills the tube across the full tube cross-section at least at the tube ends, immobilizing contaminations in the filled portion inside the tube (11); c) curing the polymer, then detaching the tubes with cured polymer the detached tubes being sealed by the polymer d) sorting out the detached tubes with polymer.

Abstract: A securing device is installable on an outer circumferential surface of a nuclear reactor core shroud and in contact with an inner circumferential surface of a pressure vessel. The securing device includes a base configured for contacting the outer circumferential surface of the nuclear reactor core shroud. The securing device also includes a radial extender including an actuator, a stationary support section fixed to the base and a movable contact section. The radial extender is configured such that the movable contact section is movable along the stationary support section by the actuator to force the movable contact section radially into the inner circumferential surface of the pressure vessel.

Abstract: A detector (10) for high-energy radiography includes, in the following order: a metal screen (12) arranged to receive incident radiation, at least part of the incident radiation being transmitted through the metal screen and forming a transmitted radiation, a scintillator component (14) arranged to convert the radiation transmitted by the metal screen into light, and a detection layer (16) arranged to detect the intensity of the light emitted by the scintillator component. The screen (12) is made of a metal having an atomic number that is strictly greater than 70 or is made of an alloy comprising at least 50% mass content of one or more metals having an atomic number that is strictly greater than 70 and in that the thickness of the screen is between 20 ?m and 900 ?m.

Abstract: An unlatching tool configured for actuating a movable section of a control rod drive shaft in a pressurized water reactor includes a base; a gripper assembly configured for gripping the movable section of the control rod drive shaft; a rod movably connecting the gripper assembly to the base; and a mechanical actuator fixed to the base and configured for rotating the rod to raise and lower the gripper assembly. A method for actuating a movable section of a control rod drive shaft includes installing an unlatching tool on the control rod drive shaft; latching the unlatching tool to a stationary section of the control rod drive shaft; and raising a rod connected to a gripper assembly to cause the gripper assembly to grip the movable section and move the movable section upward.

Abstract: A radionuclide generation system including a tube system configured to permit insertion and removal of irradiation targets into an instrumentation finger of a nuclear reactor, and an irradiation target drive system configured to insert the irradiation targets into the instrumentation finger and to remove the irradiation targets from the instrumentation finger. The radionuclide generation system further includes an instrumentation and control unit which is linked to an online core monitoring system and being configured to calculate optimal irradiation locations for the irradiation targets based on the actual state of the reactor as provided by the online core monitoring system.

Abstract: A device for detecting a defect on a surface including an optical device (14) suitable for acquiring an image of the surface in a given optical direction, a lighting device (15) comprising a plurality of light sources (16), the light sources (16) being arranged in a hemisphere (20), each light source (16) having an off and an on state, an electronic calculation device (18). The electronic calculation device (18) is able to control the optical device (14) and the lighting device (15) so that the optical device (14) acquires a plurality of images of the surface, different light sources (16) or different combinations of light sources (16) being switched on for each image, the hemisphere (20) having a diameter D smaller than or equal to 50 mm.

Abstract: A nuclear facility has a fuel pool containing a liquid and an associated cooling circuit for a circulating cooling agent. The cooling circuit contains a cooling module with a first heat exchanger which immerges into the liquid, a second heat exchanger which is located outside the fuel pool, and connecting lines between the first exchanger and the second heat exchanger. In order to provide for reliable cooling even if a filling level drops, the cooling module contains a lifting body and floats in the liquid such that its altitude varies with the filling level of the liquid in the fuel pool.

Abstract: A method of decontaminating a metal surface located on a component within a nuclear plant, in particular within the cooling system of a nuclear power plant, which is covered with a metal oxide layer containing radioactive substances, the method including a decontamination step in which a metal oxide layer pretreated in an oxidation step is contacted with an aqueous solution of an organic acid to dissolve the metal oxide layer, forming a decontamination solution containing the organic acid, metal ions and the radioactive substances, and passing the decontamination solution over an ion exchanger to immobilize metal ions and radioactive substances. An oxidant selected from oxygen, air, hydrogen peroxide and ozone is dosed into the decontamination solution to control the dissolution rate of the metal oxide layer. The method is particularly suitable for large-scale system decontamination and ensures high process stability.

Abstract: An detector-assembly for measuring flux in a nuclear reactor core includes self-powered in-core detector arrangements each for measuring flux at a different one of a plurality of axial locations in the core, and an assembly connector configured to be connected to a power plant connector. The assembly connector includes a plurality flux signal terminals each connected to one of self-powered in-core detector arrangements. At least one of the self-powered in-core detector arrangements comprises a set of at least two self-powered in-core detectors for measuring flux at a same one of the axial locations in the nuclear reactor core. Each of the at least two self-powered in-core detectors includes a sheath, a detector material section inside the sheath, an insulator between the sheath and the detector material, and a flux signal output line. The flux signal output lines of the at least two self-powered in-core detectors are joined together.

Abstract: A cable lead-through assembly (2) includes s frame (10) delimiting a cable reception space (20); and an in-frame sub-system (11) configured for securing cables (1) to the frame (10). The in-frame sub-system (11) includes at least two plates (32) intended for extending in said cable reception space (20), the plates (32) being configured for being coupled to the frame (10) and for forming between each other at least one cable's path for at least one cable (1); securing means (14) configured for securing the or each cable (1) to a corresponding plate (32); and a locking unit (16) coupled to the frame (10). The locking unit (16) has an at-rest configuration and an operational configuration. The locking unit (16) is configured for displacing the plates (32).

Abstract: A nuclear power plant comprising a primary coolant circuit, a steam-water circuit separated from the primary coolant circuit and a steam generator connected to the primary coolant circuit and the steam-water circuit to transfer heat from the primary coolant circuit into the steam-water circuit has at least one dosing point in the steam-water circuit to inject a reducing agent into the steam-water circuit, wherein the reducing agent is an organic compound consisting of carbon, hydrogen and oxygen. Furthermore, a method for operating said nuclear power plant and the use of the method for downtime preservation of the secondary side of a steam generator of a nuclear power plant are provided.

Abstract: A depressurization and cooling system for steam and/or condensable gases located in a containment. The system contains a steam condenser having an upstream port connected to the containment through an exhaust line and a downstream port connected to the containment through a backfeed line. The backfeed line contains a backfeed compressor. A re-cooling system for re-cooling the steam condenser is provided. The depressurization and cooling system is effective for re-cooling of the steam condenser. Accordingly, this is achieved as the re-cooling system is self-sustainable.

Abstract: The invention relates to a flexible lance for machining or inspecting a tubesheet of a boiler, having a first strip made of a flexible, metallic material and a second strip made of a flexible, metallic material, wherein the second strip is arranged on the first strip in the longitudinal direction, and wherein at least the second strip has a shaped portion extending in the longitudinal direction for receiving a supply line for a machining or inspection head arranged at the free end of the flexible lance, and wherein the first strip is connected to the second strip such that an open side of the shaped portion is covered by the first strip so as to form a guide channel, and wherein at least one edge region of the flexible lance, extending in the longitudinal direction, is formed only by the first strip or the second strip.

Abstract: An electronic device (18) is for managing the display of data to control a nuclear power plant. The data comes from a plurality of electronic control units (16A, 16B, 16C). Each control unit is configured to perform at least one action from among acquiring a value measured by a sensor (12A, 12B, 12C) and controlling an actuator (14A, 14B, 14C), the control units, sensor(s) and/or actuator(s) being according to several different nuclear safety classes. This electronic device (18) is able to be connected to the control units, and includes a set (25) of electronic module(s) (26A, 26B, 26C) for creating overlay(s) (28A, 28B, 28C). Each overlay contains information associated with one or several control units and according to a respective safety class; and a module (30) for generating a page (32) to be displayed, by superposition of several separate overlays.

Abstract: A programmable logic circuit (10) for controlling an electrical facility, in particular a nuclear facility, includes an operating unit (14). The operating unit includes a plurality of types of functional blocks (FB1, FBi, FBN), two distinct types of functional blocks being suitable for executing at least one distinct function, at least one processing module suitable for receiving at least one sequence (46) of functional block(s) to be executed, and at least one internal memory (38) configured to store at least said sequence (46). The programmable logic circuit (10) includes a single functional block of each type, a given functional block being suitable for being called several times, and an execution module (22) configured to execute the called functional block(s) in series, according to said sequence (46).

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).