Abrégé

The present disclosure relates to reducing losses in the effective delayed neutron fraction during the operation of a reactor, making it possible to provide for a high efficiency of burning out of minor actinides, and also that of increasing the leak-tight integrity of the primary circuit and the reliability of the reactor. The above-mentioned technical result is achieved in an integral molten salt fast reactor with a circulating fuel composition, comprising a vessel with inlet and outlet secondary circuit pipelines and a connection pipe for initial filling and replenishment with molten salt coolant, heat exchangers of the primary/secondary circuit, a side reflector, an upper reflector and a lower reflector, a core with a shell, and a main circulation pipe, wherein the side reflector is made of sections between which the heat exchangers of the primary/secondary circuit are arranged such that they lie flush against the shell of the core.

Classes IPC  ?

• G21C 15/10 - Aménagement ou disposition de passages dans lesquels la chaleur est transférée au réfrigérant, p. ex. pour la circulation du réfrigérant à travers les supports des éléments combustibles provenant du réflecteur ou de l'écran thermique
• G21C 1/22 - Réacteurs hétérogènes, c.-à-d. dans lesquels le combustible et le modérateur sont séparés utilisant du combustible liquide ou gazeux
• G21C 15/28 - Emploi de réfrigérants spécifiques

Abrégé

The present disclosure relates to nuclear chemical, particularly radiochemical, technologies at different stages of the nuclear fuel cycle, such as the production of purified nuclear materials (uranium, zirconium) or the reprocessing of spent nuclear fuel from nuclear power stations, in which extraction processes and operations for purifying nuclear materials are used. An example method, which includes the partial decomposition of nitric acid during continuous evaporation while a solution containing a reducing agent is fed into the bottom part of an evaporator having a circulating bottoms solution, consists in that the process is carried out such that the solution is kept in the bottom part of the evaporator for more than 2 hours under the addition of an aqueous solution of formaldehyde and formic acid (hereinafter “the mixture”) or a solution of formic acid after the process has been started using the mixture.

Classes IPC  ?

• G21F 9/08 - Traitements par évaporationTraitements par distillation

Abrégé

The invention relates to nuclear engineering, and more particularly to a uranium-based metal-ceramic alloy, and is suitable for use in the manufacture of nuclear fuel for fuel elements for thermal-neutron and fast-neutron reactors, as well as in the creation of research reactors. A uranium-based alloy contains 2.5-12 wt% molybdenum, and principal ceramic phases containing oxygen, carbon or nitrogen in an amount of 0.1-3.0 wt%, and may be doped with additional elements in the form of silicon, tin, chromium or aluminium, which form intermetallic phases, as well as with elements that are gamma stabilizers, specifically niobium, titanium or zirconium. The claimed uranium-based metal-ceramic alloy containing molybdenum and having a composite metal-ceramic alloy structure consists of a y-(U-Mo) matrix phase and a ceramic and/or intermetallic phase or phases. The alloy has a low thermal neutron capture cross section and a high liquidus temperature and is compatible with structural materials, including steel or aluminium cladding. The thermodynamic stability and reaction resistance of the alloy are also increased.

Classes IPC  ?

• C22C 43/00 - Alliages contenant un élément radioactif
• G21C 3/60 - Combustible métalliqueDispersions intermétalliques

Abrégé

The invention relates to nuclear engineering and is suitable for use as nuclear fuel in the manufacture of fuel elements for VVER-type thermal reactors. A uranium-based alloy contains: 2.0-7.0 wt% silicon, 0.1-2.0 wt% aluminium, at least one element selected from the group consisting of: 0.15-2.0 wt% carbon, 0.15-2.0 wt% oxygen, 0.15-1.0 wt% nitrogen, and the balance uranium. The uranium-based alloy may additionally contain at least one element selected from the group consisting of: 0.15-5.0 wt% molybdenum, 0.15-2.0 wt% niobium, 0.15-2.0 wt% zirconium, 0.15-2.0 wt% titanium, 0.1-2.0 wt% tin, 0.1-2.0 wt% chromium. This makes it possible to produce a high-density uranium-based alloy with a high uranium content while at the same time preserving thermodynamic stability, a high liquidus temperature and high radiation resistance.

Classes IPC  ?

• C22C 43/00 - Alliages contenant un élément radioactif

Abrégé

This disclosure enables a creation of a detachable connection between a linear motor tubular armature and a vertical cylindrical rod of an actuator of a control and protection system of a nuclear reactor. Such configuration reduces a dose load on a member of personnel, as well as provides an increase in reliability of a coupling of the linear motor tubular armature and the vertical cylindrical rod in conditions of high temperature and radiation.

Classes IPC  ?

• G21C 7/00 - Commande de la réaction nucléaire
• G21C 7/10 - Structures des éléments de commande

Abrégé

The invention relates to the field of nuclear chemical, particularly radiochemical, technologies at different stages of the nuclear fuel cycle, such as the production of purified nuclear materials (uranium, zirconium) or the reprocessing of spent nuclear fuel from nuclear power stations, in which extraction processes and operations for purifying nuclear materials are used. The essence of the present method, which includes the partial decomposition of nitric acid during continuous evaporation while a solution containing a reducing agent is fed into the bottom part of an evaporator having a circulating bottoms solution, consists in that the process is carried out such that the solution is kept in the bottom part of the evaporator for more than 2 hours under the addition of an aqueous solution of formaldehyde and formic acid (hereinafter "the mixture") or a solution of formic acid after the process has been started using the mixture. This makes it possible to select a regime in which, during evaporation of a model highly active raffinate under conditions of a given concentration level (a specific volume of bottoms solution that is not more than 0.4 m3/ton of radioactive waste), barium nitrate is not precipitated and nitrous oxide is not released. In addition, the fire and explosion safety of the process is increased due to a significant (up to tenfold) reduction in the concentration of formaldehyde in the reducing agent, and the possibility of continuing the process in the complete absence of formaldehyde, using a solution of formic acid.

Classes IPC  ?

• G21F 9/04 - Traitement des liquides
• G21F 9/08 - Traitements par évaporationTraitements par distillation

Abrégé

The invention relates to the field of nuclear chemical, particularly radiochemical, technologies at different stages of the nuclear fuel cycle, such as the production of purified nuclear materials (uranium, zirconium) or the reprocessing of spent nuclear fuel from nuclear power stations, in which extraction processes and operations for purifying nuclear materials are used. The essence of the present method, which includes the partial decomposition of nitric acid during continuous evaporation while a solution containing a reducing agent is fed into the bottom part of an evaporator having a circulating bottoms solution, consists in that the process is carried out such that the solution is kept in the bottom part of the evaporator for more than 2 hours under the addition of an aqueous solution of formaldehyde and formic acid (hereinafter "the mixture") or a solution of formic acid after the process has been started using the mixture. This makes it possible to select a regime in which, during evaporation of a model highly active raffinate under conditions of a given concentration level (a specific volume of bottoms solution that is not more than 0.4 m3/ton of radioactive waste), barium nitrate is not precipitated and nitrous oxide is not released. In addition, the fire and explosion safety of the process is increased due to a significant (up to tenfold) reduction in the concentration of formaldehyde in the reducing agent, and the possibility of continuing the process in the complete absence of formaldehyde, using a solution of formic acid.

Classes IPC  ?

• G21F 9/04 - Traitement des liquides
• G21F 9/08 - Traitements par évaporationTraitements par distillation

Abrégé

A method of improving explosion safety in closed spaces by attenuating the effect of a combustion wave or shock wave on a protected surface consists in placing obstructions before the protected surface in the form of elastic membranes filled with a flame-retardant substance. A non-flammable gas is used as the substance filling the membranes; the membranes themselves are made of a material that disintegrates during, and under the action of, displacement of the front of a combustion wave or shock wave along the surface of the membranes. The membranes are filled with a non-flammable gas immediately after flammable gas is detected at a dangerous concentration in the space in front of the protected object.

Classes IPC  ?

• F42D 5/045 - Moyens pour absorber ou amortir les ondes de détonation

Abrégé

The invention relates to nuclear engineering. A method of monitoring the radionuclide content of radioactive waste includes a preparatory step in which radioactive waste streams are identified and the radionuclide vectors thereof are determined. In order to determine a radionuclide vector in a stream, samples are collected. The specific activities and the standard uncertainty of the activities of said samples are determined in relation to the activity of a reference radionuclide. As reference radionuclide, the activation product of a lead coolant 207Bi is used, the specific activity of which is determined using a gamma-ray spectrometry apparatus having a resolution of not less than 8% along the 0.662 keV line, and 210Pb, 202Pb and 205Pb are included in the list of target hard-to-detect radionuclides(HD-RN) of the radionuclide vector. Data about the activity of gamma-emitting radionuclides in a test sample are used in the processing of liquid scintillation spectrometer readings. Processing is carried out using the generalized least squares method, taking into account both the uncertainty values of the specific activity measurements of the reference radionuclide and those of the HD-RN as weights of the measured values. The invention makes it possible to increase selectivity, accuracy and sensitivity when determining the HD-RN content of radioactive waste.

Classes IPC  ?

• G01T 1/16 - Mesure de l'intensité de radiation
• G21C 17/06 - Dispositifs ou dispositions pour la surveillance ou le test du combustible ou des éléments combustibles en dehors du cœur du réacteur, p. ex. pour la consommation ou pour la contamination

Abrégé

A fast-neutron nuclear reactor fuel assembly having fuel rods. Each fuel rod has nuclear fuel disposed in a sealed housing in the form of a tubular steel shell and end parts. A steel spacer element is wound in a coil with a specific pitch on the outside surface of the shell and is fastened on the end parts. The spacer element is in the form of a metallic band twisted around its longitudinal axis. The width of said band is approximately equal to the minimum distance between adjacent fuel rods in the fuel assembly. A transverse cross-sectional area of the band is within a range from 0.10 to 0.50 times the area of a circle described around the width of the band.

Classes IPC  ?

• G21C 3/12 - Moyens formant partie de l'élément pour le positionner dans le cœur du réacteurEntretoises extérieures à cet effet
• G21C 3/338 - Éléments d'espacement hélicoïdaux
• G21C 1/02 - Réacteurs de fission rapides, c.-à-d. réacteurs n'utilisant pas de modérateur

Abrégé

Material and power techniques for producing solid three-dimensional materials. In one aspect, a composite material is based on a quasicrystal powder of an Al—Cu—Fe system with a nickel binder, the composite material containing a reinforcing nickel lattice. In a second aspect, the composite material is obtained by applying a nickel coating to quasicrystal powder particles of an Al—Cu—Fe system. The quasicrystal powder can be treated in plasma to form a thin (10-20 nm) nickel coating on the surface of the powder particles. The treated powder, which is a dispersed composite material, can then be pressed at room temperature under quasi-hydrostatic conditions at a pressure of more than 1.5 GPa. In some aspects, the improved characteristics of the three-dimensional materials include providing three-dimensional fully dense composite quasicrystal materials with improved mechanical properties, a decreased coefficient of friction and increased resistance to mechanical wear, and creating additional possibilities for new technological applications.

Classes IPC  ?

• B22F 3/02 - Compactage seul
• B22F 1/02 - Traitement particulier des poudres métalliques, p.ex. en vue de faciliter leur mise en œuvre, d'améliorer leurs propriétés; Poudres métalliques en soi, p.ex. mélanges de particules de compositions différentes comportant un enrobage des particules
• B22F 3/24 - Traitement ultérieur des pièces ou objets

Abrégé

The invention relates to the field of nuclear technology. A detachable connection between a tubular armature of a linear motor and a vertical cylindrical rod of a nuclear-reactor actuating mechanism is designed such that the rod is arranged in a guide tube. L-shaped slots are formed at the end of the armature and vertical slots are formed thereabove. The rod is mounted in the armature with an annular gap into which a tubular fork with prongs is placed. Furthermore, radial protrusions are formed on the rod. In the guide tube, below the vertical armature slots, a bushing with grooves is fastened in coaxial alignment with the armature such that the rod protrusions can be inserted into (removed from) said grooves, and the lower part of the armature is covered by a longitudinally immovable plug, on the lateral surface of which grooves are formed for the insertion (removal) of the fork prongs. The invention makes it possible to increase the reliability of the connection between armature and rod under conditions of high temperature and radiation.

Classes IPC  ?

• G21C 7/12 - Moyens pour amener les éléments de commande dans la position désirée
• G21C 9/02 - Moyens pour effectuer une réduction très rapide du facteur de réactivité dans des conditions défectueuses, p. ex. fusible pour réacteur
• G21C 17/10 - Combinaison structurelle de l'élément combustible, de la barre de commande, du cœur du réacteur, ou de la structure du modérateur avec des instruments sensibles, p. ex. pour la mesure de la radioactivité, des contraintes

Abrégé

The invention relates to the field of nuclear technology. A detachable connection between a tubular armature of a linear motor and a vertical cylindrical rod of a nuclear-reactor actuating mechanism is designed such that the rod is arranged in a guide tube. L-shaped slots are formed at the end of the armature and vertical slots are formed thereabove. The rod is mounted in the armature with an annular gap into which a tubular fork with prongs is placed. Furthermore, radial protrusions are formed on the rod. In the guide tube, below the vertical armature slots, a bushing with grooves is fastened in coaxial alignment with the armature such that the rod protrusions can be inserted into (removed from) said grooves, and the lower part of the armature is covered by a longitudinally immovable plug, on the lateral surface of which grooves are formed for the insertion (removal) of the fork prongs. The invention makes it possible to increase the reliability of the connection between armature and rod under conditions of high temperature and radiation.

Classes IPC  ?

• G21C 7/12 - Moyens pour amener les éléments de commande dans la position désirée
• G21C 9/02 - Moyens pour effectuer une réduction très rapide du facteur de réactivité dans des conditions défectueuses, p. ex. fusible pour réacteur
• G21C 17/10 - Combinaison structurelle de l'élément combustible, de la barre de commande, du cœur du réacteur, ou de la structure du modérateur avec des instruments sensibles, p. ex. pour la mesure de la radioactivité, des contraintes

Abrégé

The invention relates to means for protecting the environment from the consequences of fires complicated by a radiation factor. A composition for dust suppression and containment of radioactive products of combustion after a fire with a radiation factor has been extinguished comprises, as a surfactant, a mixture of an anionic, a non-ionic and an amphoteric surfactant, and has the following ratio of components: 3.0-7.0% by weight of an aqueous solution of polyvinyl alcohol (in terms of a mass fraction of dry product); 0.1-0.3% by weight of plasticizer; 11.0-29.0% by weight of surfactant; with water making up the remainder. The invention makes it possible to carry out dust suppression and containment of radioactive products of combustion which are formed on surfaces, including at elevated temperatures, after a fire has been extinguished.

Classes IPC  ?

• G21F 9/30 - Traitements
• G21F 9/00 - Traitement des matériaux contaminés par la radioactivitéDispositions à cet effet pour la décontamination

Abrégé

The invention relates to atomic engineering, specifically to steam generators having a liquid metal coolant. Proposed is an inverse steam generator for a fast neutron reactor having a lead coolant, said steam generator comprising a cylindrical housing having a bundle of heat transfer tubes disposed therein, the ends of said bundle being fastened in tube sheets having intermediate support grids, a spherical inlet chamber and a spherical outlet chamber for supplying a liquid metal coolant, a lower inlet pipe for water, and an upper outlet pipe for steam. The cylindrical housing is arranged horizontally and is bent into a Z-shape having a decrease in height, wherein the bundle of heat exchange tubes is also Z-shaped, conforming to the bend of the cylindrical housing, which allows the structure to be self-compensating, decreases the mass of a steam generator structure, and reduces operational costs.

Classes IPC  ?

• F22B 1/06 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant un corps fonduEmploi de métal fondu, p. ex. du zinc, comme milieu transmetteur de chaleur
• G21D 1/00 - Détails des installations à énergie nucléaire

Abrégé

The invention relates to atomic engineering, specifically to steam generators having a liquid metal coolant. Proposed is an inverse steam generator for a fast neutron reactor having a lead coolant, said steam generator comprising a cylindrical housing having a bundle of heat transfer tubes disposed therein, the ends of said bundle being fastened in tube sheets having intermediate support grids, a spherical inlet chamber and a spherical outlet chamber for supplying a liquid metal coolant, a lower inlet pipe for water, and an upper outlet pipe for steam. The cylindrical housing is arranged horizontally and is bent into a Z-shape having a decrease in height, wherein the bundle of heat exchange tubes is also Z-shaped, conforming to the bend of the cylindrical housing, which allows the structure to be self-compensating, decreases the mass of a steam generator structure, and reduces operational costs.

Classes IPC  ?

• G21D 1/00 - Détails des installations à énergie nucléaire
• F22B 1/06 - Méthodes de production de vapeur caractérisées par le genre de chauffage par exploitation de l'énergie thermique contenue dans une source chaude la source chaude étant un corps fonduEmploi de métal fondu, p. ex. du zinc, comme milieu transmetteur de chaleur

Abrégé

The invention relates to nuclear engineering and can be used for monitoring the state of a space above the core of a nuclear reactor containing a liquid metal coolant. The operating principle of an ultrasonic monitoring system is based on exciting, and obtaining in response, ultrasonic signals which are reflected from structural elements located in a space (a gap being monitored) between the top level of the heads of fuel rod assemblies and the bottom level of rotating plugs of a nuclear reactor that is cooled by an opaque coolant, for example liquid sodium. This system serves for detecting, in the space being monitored (gap being monitored), obstacles to rotation of the rotating plugs during refuelling operations. To increase the reliability of detecting obstacles in the space being monitored above the core and to determine the location of said obstacles, the ultrasound reflector is configured in the form of a ring on which at least one row of vertical cylindrical rods is arranged, the ring is attached to one of the thermal screens surrounding the reactor core, preferably one proximate to the nuclear reactor vessel, wherein the spacing at which the cylindrical rods are arranged in the row is less than the spacing between the assemblies.

Classes IPC  ?

• G21C 17/00 - SurveillanceTests
• G01N 29/04 - Analyse de solides

Abrégé

The invention relates to nuclear engineering and can be used for monitoring the state of a space above the core of a nuclear reactor containing a liquid metal coolant. The operating principle of an ultrasonic monitoring system is based on exciting, and obtaining in response, ultrasonic signals which are reflected from structural elements located in a space (a gap being monitored) between the top level of the heads of fuel rod assemblies and the bottom level of rotating plugs of a nuclear reactor that is cooled by an opaque coolant, for example liquid sodium. This system serves for detecting, in the space being monitored (gap being monitored), obstacles to rotation of the rotating plugs during refuelling operations. To increase the reliability of detecting obstacles in the space being monitored above the core and to determine the location of said obstacles, the ultrasound reflector is configured in the form of a ring on which at least one row of vertical cylindrical rods is arranged, the ring is attached to one of the thermal screens surrounding the reactor core, preferably one proximate to the nuclear reactor vessel, wherein the spacing at which the cylindrical rods are arranged in the row is less than the spacing between the assemblies.

Classes IPC  ?

• G01N 29/04 - Analyse de solides
• G21C 17/00 - SurveillanceTests

Abrégé

The method of launching natural circulation of the liquid metal coolant in the heat sink circuit of the fast neutron nuclear reactor without connection to the main heat source (first circuit heat sink) and without using pumping equipment, but only as a result of electric heating of the downing and lifting sections of the heat sink circuit to the specified temperatures and, as a consequence, the occurring difference in the densities of the coolant on the lifting and downing sections of the heat sink circuit.

Classes IPC  ?

• G21C 15/247 - Cyclage du fluide réfrigérant pour des liquides pour des métaux liquides
• G21C 15/00 - Dispositions pour le refroidissement à l'intérieur de l'enceinte sous pression contenant le cœurEmploi de réfrigérants spécifiques
• G21C 1/02 - Réacteurs de fission rapides, c.-à-d. réacteurs n'utilisant pas de modérateur

Abrégé

A method for searching for and detecting gamma radiation sources in conditions of nonuniform radioactive contamination is provided. Stages in which a source of maximally active radiation is determined, the radiation power is measured with a collimated detector and at the same time the distance to the source is determined with the aid of a laser detector rangefinder. Readings of the laser rangefinder and the value of a dose rate are established by the detector are recorded. The dose rate of the radiation of the actual source is calculated, after which, to verify the distance measured to the radiation source, the aiming axis of the rangefinder is moved for a distance horizontally. The measurement is repeated and the distance recorded. The results of successive measurements of the distance are compared. If there is a divergence in the measurements within the laser rangefinder error limits, the information is acknowledged as reliable.

Classes IPC  ?

• G01T 1/167 - Mesure du contenu radioactif des objets, p. ex. contamination
• G01C 3/08 - Utilisation de détecteurs électriques de radiations
• G01T 1/169 - Exploration, localisation de surfaces contaminées

Abrégé

The invention relates to the field of environmental protection, more specifically to the field of processing radioactive waste, and can he used for the safe and effective handling of a large quantity of liquid radioactive waste of various activity levels that has been formed as the result of decontaminating protective equipment of boxes and chambers, and makes it possible to decrease the volume of stored waste by solidifying same and incorporating same into a ceramic matrix. For this purpose, radioactive solutions after decontamination of surfaces of protective equipment are evaporated as alkaline and acidic solutions containing sodium hydroxide, potassium permanganate, oxalic acid, and nitric acid until a solid residue forms, and are calcined, and the calcinate is mixed with components of a fusion mixture containing oxides of titanium, calcium, iron (III), zirconium, and manganese (IV) and aluminum in a specified ratio, and fused.

Classes IPC  ?

• G21F 9/16 - Traitements par fixation dans un milieu solide stable
• C04B 35/46 - Produits céramiques mis en forme, caractérisés par leur compositionCompositions céramiquesTraitement de poudres de composés inorganiques préalablement à la fabrication de produits céramiques à base d'oxydes à base d'oxydes de titane ou de titanates
• C04B 35/64 - Procédés de cuisson ou de frittage
• G21F 9/08 - Traitements par évaporationTraitements par distillation
• G21F 9/30 - Traitements

Abrégé

i relative to the direction of a neutron beam.

Classes IPC  ?

• G01N 23/05 - Recherche ou analyse des matériaux par l'utilisation de rayonnement [ondes ou particules], p. ex. rayons X ou neutrons, non couvertes par les groupes , ou en transmettant la radiation à travers le matériau et formant des images des matériaux en utilisant des neutrons

Abrégé

A fuel assembly design for nuclear reactors that is used in fast neutron reactor cores to provide more reliable spacing of a fuel element bundle in a fuel assembly and reduced local stress in the cladding of the fuel elements in the region where the elements are in contact with spacing elements. The fuel assembly has a top nozzle and a bottom nozzle which are connected to one another by a jacket. A bundle of rod-type fuel is elements arranged in the fuel assembly with the aid of a grid and spiral spacer elements wrapped around the cladding of each fuel element. At least the peripheral fuel elements in the bundle are provided with spacer elements in the form of thin-walled tubes with longitudinal through slots, wherein the elements have a substantially oval cross section in the regions where they are in contact with the jacket.

Classes IPC  ?

• G21C 3/338 - Éléments d'espacement hélicoïdaux
• G21C 3/32 - Faisceaux d'éléments combustibles en forme d'aiguilles, de barres ou de tubes parallèles
• G21C 3/334 - Assemblage des faisceaux

Abrégé

A thermonuclear reactor is provided having a vacuum casing and blanket modules connected thereto with flexible supports. The flexible supports are formed from a material with high electrical conductivity. Each flexible support is secured at one end on the vacuum casing and at the other end on a blanket module, the two secured ends of each flexible support face the blanket module. The flexible support is formed from two hollow cylindrical elements placed one in the other and perforated by longitudinal slots in a part free from mountings. The ends of the hollow cylindrical elements opposite the secured ends are connected electrically and mechanically. The technical result consists in diverting eddy currents away from a blanket module of a thermonuclear reactor and simultaneously eliminating electrical connectors from the composition of a blanket and reducing bunching on a blanket module side facing the vacuum casing.

Classes IPC  ?

• H05H 1/12 - Dispositions pour confiner le plasma au moyen de champs électriques ou magnétiquesDispositions pour chauffer le plasma utilisant uniquement des champs magnétiques appliqués dans lesquels l'enceinte forme une boucle fermée
• G21B 1/13 - Première paroiParoi de couvertureDivertor
• G21B 1/17 - Chambres à videInstallations de vide

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for electrically connecting components situated inside a nuclear fusion reactor chamber to the vacuum vessel of the reactor. A device for electrically connecting components situated inside a nuclear fusion reactor chamber to the vacuum vessel of the reactor comprises two identical stacks of electrically conductive plates. The electrically conductive plates are in the shape of a symmetrical wave having at least one full period. The plates in a stack are nested one inside another and are connected to flanges for attachment to a component situated inside the chamber and to the vacuum vessel. The stacks of electrically conductive plates are mounted with mirror symmetry about a line that passes through the centers of symmetry of the flanges.

Classes IPC  ?

• G21B 1/17 - Chambres à videInstallations de vide

Abrégé

AbstractThe invention relates to the field of nuclear engineering and can be used in actuators of a nuclear reactor control and protection system. An actuator of a nuclear reactor control and protection system comprises: a linear step motor comprising an armature; a rod which is arranged coaxially with the armature and which is rigidly connected to the armature to enable a joint vertical movement and a rotation about a common vertical axis, and which is designed to be capable of forming an L-shaped bayonet connection with a working member; and a lock to prevent spontaneous rotation of the rod. The lock comprises a guiding section which is arranged inside the armature and which is provided with a flange and a longitudinal through slot; a cross-member which is rigidly connected to the armature and which is mounted in the slot such as to be capable of a vertical movement therein during a working stroke; a fixed ring, on which the inner surface of the flange rests; and a vertical pin. Through slots are arranged equidistantly in the outside rim of the flange, and openings are arranged equidistantly about the circumference of the fixed ring, the vertical pin being mounted in one of said openings such as to pass through one of the through slots in the flange. The technical result of the present invention is that of preventing spontaneous disengagement of the bayonet connection, while also reducing the number of steps required to engage and disengage said connection. Date recue / Date received 2021-12-17

Classes IPC  ?

• G21C 7/14 - Aménagements de conduite mécaniques

Abrégé

The invention relates to the field of nuclear engineering and can be used in nuclear reactor control and protection system actuators. An actuator of a nuclear rector control and protection system comprises: a linear stepper motor having an armature; a rod which is arranged coaxially with the armature, and which is rigidly connected to the armature to provide vertical movement and rotation about a vertical axis, and which is designed to be capable of forming an L-shaped bayonet connection with a working member; and a lock to prevent spontaneous rotation of the rod. The lock comprises a guide which is arranged inside the armature and which is provided with a flange and a longitudinal through slot; a cross-member which is rigidly connected to the armature and which is mounted in the slot such as to be capable of vertical movement therein during a working stroke; a fixed ring, on which the inside surface of the flange rests; and a vertical pin. Through slots are arranged equidistantly on the outside rim of the flange, and openings are arranged equidistantly about the circumference of the fixed ring, the vertical pin being mounted in one of said openings such as to pass through one of the through slots in the flange. The technical result of the present invention is that of preventing spontaneous disengagement of the bayonet connection, while also reducing the number of steps required to engage and disengage said connection.

Classes IPC  ?

• G21C 7/14 - Aménagements de conduite mécaniques

Abrégé

The invention relates to the field of technology concerned with the development of methods and instruments for detecting radioactive substances. The structure of the proposed invention is comprised of two coaxially arranged cylinders: an inner cylinder made of lead, which acts both as a gamma shield and as a neutron multiplier; and an outer cylinder made of polyethylene, which acts as a neutron thermalizer. Fifteen helium-3 counters with cadmium filters are equidistantly built into the wall of the outer cylinder in a circle, parallel to the generatrix. An isotropic deuterium-tritium 14 MeV neutron generator is mounted in the wall of the outer cylinder, perpendicular to the generatrix. A pedestal capable of vertical axial movement is disposed in the lower part of the inner cylinder. Prior to loading into the apparatus, a vessel and a structural material contained therein are subjected to gamma scanning. Then, by means of the movable pedestal, the vessel is mounted in the inner cylinder such that the centre of mass of the structural material is situated opposite detectors. The proposed device provides high-accuracy, high-speed detection of fissile materials.

Classes IPC  ?

• G01N 23/222 - Recherche ou analyse des matériaux par l'utilisation de rayonnement [ondes ou particules], p. ex. rayons X ou neutrons, non couvertes par les groupes , ou en mesurant l'émission secondaire de matériaux utilisant l'analyse par activation en utilisant l'analyse par activation neutronique [NAA]

Abrégé

A method for reprocessing nitride spent nuclear fuel in molten salts is proposed, comprising chlorinating the fuel in a melt of a mixture of alkali and/or alkaline earth metal chlorides containing cadmium dichloride. The chlorination is carried out in an apparatus for reprocessing nitride spent nuclear fuel using an inert gas atmosphere. The apparatus has a heatable zone containing a reactor with molten chloride and nitride spent nuclear fuel submerged therein, and also a cold zone arranged under the reactor. In the chlorination process, the zone of the apparatus containing the reactor is heated to a temperature greater than 700°C, the nitride spent nuclear fuel is kept in the melt until fully chlorinated, wherein the cold zone of the apparatus is used for crystallizing metallic cadmium which forms during the chlorination. The technical result of the invention consists in increasing the degree of conversion of nitride spent nuclear fuel in molten chloride to 100%, which reduces or completely excludes the necessity of additional stages of repeated filtration and reprocessing of spent nuclear fuel.

Classes IPC  ?

• G21C 19/42 - Retraitement des combustibles irradiés

Abrégé

The invention relates to powder techniques for producing solid three-dimensional materials. The technical result of the invention consists in improving the characteristics of the three-dimensional materials produced and creating additional possibilities for new technological applications by improving the properties of said materials. The technical result is achieved with the aid of a composite material based on a quasicrystal powder of an Al-Cu-Fe system with a nickel binder, said composite material containing a reinforcing nickel lattice, and is achieved by the fact that a nickel coating is applied to quasicrystal powder particles of an Al-Cu-Fe system (to this end, the quasicrystal powder is advantageously treated in plasma, as a result of which a thin (10-20 nm) nickel coating forms on the surface of the powder particles). The treated powder, which is a dispersed composite material, is then pressed at room temperature under quasi-hydrostatic conditions at a pressure of more than 1.5 GPa. Using the method developed, three-dimensional fully dense composite quasicrystal materials were produced with high mechanical properties, a decreased coefficient of friction and increased resistance to mechanical wear.

Classes IPC  ?

• C22C 49/06 - Aluminium
• C22C 1/04 - Fabrication des alliages non ferreux par métallurgie des poudres
• B22F 3/12 - Compactage et frittage
• B82Y 30/00 - Nanotechnologie pour matériaux ou science des surfaces, p. ex. nanocomposites
• B82Y 40/00 - Fabrication ou traitement des nanostructures

Abrégé

A device for determining the parameters of strip-type superconductors includes a generator, a generator frequency-setting element, an inductance coil connected to the generator, a receiver, a receiver frequency-setting element, and an inductance coil connected to the receiver. The generator and receiver frequency-setting elements are same type narrow-band elements. The pass bands of the generator and receiver frequency-setting elements coincide through at least half of the bandwidth of the frequency-setting element having a narrower band pass width. The generator and receiver inductance coils are arranged with a gap between the same, making it possible for a strip-type superconductor to be placed between the inductance coils. The device is provided with a temperature sensor comprising a thermistor in contact with the superconductor. The device enables highly accurate and reproducible measurement results.

Classes IPC  ?

• G01N 27/14 - Recherche ou analyse des matériaux par l'emploi de moyens électriques, électrochimiques ou magnétiques en recherchant l'impédance en recherchant la résistance d'un corps chauffé électriquement dépendant de variations de température
• H01F 6/06 - Bobines, p. ex. dispositions pour l'enroulement, l'isolation, les enveloppes ou les bornes des bobines
• H01L 39/00 - Dispositifs utilisant la supraconductivité ou l'hyperconductivité; Procédés ou appareils spécialement adaptés à la fabrication ou au traitement de ces dispositifs ou de leurs parties constitutives
• H02H 9/02 - Circuits de protection de sécurité pour limiter l'excès de courant ou de tension sans déconnexion sensibles à un excès de courant

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for electrically connecting internal elements of the reactor chamber to the vacuum vessel of the nuclear fusion reactor. The present device for electrically connecting elements inside the chamber of a reactor to the vacuum vessel of the nuclear fusion reactor comprises lamellar electrically conductive elements with surface portions oriented in different directions, said elements being stacked between flanges. The device is made as an integral unit, where profiled slots are formed with connecting walls therebetween. The connecting walls constitute the electrically conductive elements and have profiled sections of an increased thickness between the differently oriented surface portions at transition areas to the flanges provided at the end parts of the integral unit. The technical effect of the present invention is an increase in the cyclic strength of the electrically conductive elements at the transition areas between the elements and the flanges and between the differently oriented surface portions (at bends) of the elements. The invention also provides that the electrically conductive elements have similar technical characteristics.

Classes IPC  ?

• G21C 13/032 - Raccords entre le tube et la paroi d'une enceinte, p. ex. tenant compte des contraintes thermiques
• H01R 4/58 - Connexions conductrices de l'électricité entre plusieurs organes conducteurs en contact direct, c.-à-d. se touchant l'un l'autreMoyens pour réaliser ou maintenir de tels contactsConnexions conductrices de l'électricité ayant plusieurs emplacements espacés de connexion pour les conducteurs et utilisant des organes de contact pénétrant dans l'isolation caractérisées par la forme ou le matériau des organes de contact
• G21B 1/17 - Chambres à videInstallations de vide
• G21B 1/13 - Première paroiParoi de couvertureDivertor
• H01R 13/02 - Contacts
• H01R 13/00 - Détails de dispositifs de couplage des types couverts par les groupes ou
• H01R 4/00 - Connexions conductrices de l'électricité entre plusieurs organes conducteurs en contact direct, c.-à-d. se touchant l'un l'autreMoyens pour réaliser ou maintenir de tels contactsConnexions conductrices de l'électricité ayant plusieurs emplacements espacés de connexion pour les conducteurs et utilisant des organes de contact pénétrant dans l'isolation
• G21C 13/036 - Raccords entre le tube et la paroi d'une enceinte, p. ex. tenant compte des contraintes thermiques le tube traversant la paroi, c.-à-d. s'étendant de chaque côté

Abrégé

The invention relates to nuclear power and can be used in the manufacture of fuel elements for nuclear reactors. Embodiments of a welded joint between a fuel element casing and a plug comprised of high-chromium steel are proposed, providing for increased durability of the sealing of nuclear reactor fuel elements as a result of the formation of a high quality welded joint between the casing and the plug without the need for subsequent heat treatment of the weld seam, which simplifies the manufacturing process. This is achieved through the formation of a ferrite phase in the metal of the seam by adjusting the structure of a joint between the casing and the plug of ferrite-martensite and ferrite steels in various combinations and by keeping the necessary ranges of the size ratios to ensure the formation of the aforesaid phase.

Classes IPC  ?

• B23K 9/12 - Alimentation automatique en électrodes ou en pièces ou déplacement automatique des électrodes ou des pièces pour le soudage ou le découpage à l'arc en lignes continues ou par points
• B23K 9/167 - Soudage ou découpage à l'arc utilisant des gaz de protection et une électrode non consommable
• B23K 31/02 - Procédés relevant de la présente sous-classe, spécialement adaptés à des objets ou des buts particuliers, mais non couverts par un seul des groupes principaux relatifs au brasage ou au soudage
• G21C 3/07 - EnveloppesChemises caractérisées par le matériau, p. ex. alliages
• G21C 21/02 - Fabrication des éléments combustibles ou surrégénérateurs à l'intérieur de gaines non-actives
• B23K 9/16 - Soudage ou découpage à l'arc utilisant des gaz de protection
• G21C 3/04 - Détails de structure
• G21C 3/10 - Obturateurs d'extrémités
• B23K 9/00 - Soudage ou découpage à l'arc

Abrégé

The invention relates to the field of nuclear engineering and can be used to organize the natural circulation of liquid metal coolant in the heat sink of a fast neutron nuclear reactor. In order to create a driving pressure of circulation without using pumping equipment and to provide the required direction of natural circulation of the liquid metal coolant in the heat sink circuit of the fast neutron nuclear reactor in the absence of heat transfer ftom the reactor before filling the pipelines and equipment of the lifting and downing sections of the circuit, they are pre-heated by electric heating to temperatures T1 and T2, respectively, which are selected from the condition of inequality: p1(7'1) g AH1 > p2(T2) g H2 + AP

Classes IPC  ?

• G21C 15/00 - Dispositions pour le refroidissement à l'intérieur de l'enceinte sous pression contenant le cœurEmploi de réfrigérants spécifiques

Abrégé

121112221112221211222) of the liquid metal coolant in the upward and downward portions of the loop respectively.

Classes IPC  ?

• G21C 15/00 - Dispositions pour le refroidissement à l'intérieur de l'enceinte sous pression contenant le cœurEmploi de réfrigérants spécifiques

Abrégé

2 is the volume of ferrite-martensite material. Argon arc welding is carried out at a current of 14-20 A, a speed of 12-15 m/h, an arc voltage of 9-10 V and an argon flow rate of 7-8 l/min. This method provides for the desired quality of the welded joins and simplifies the fuel element manufacturing process.

Classes IPC  ?

• G21C 3/07 - EnveloppesChemises caractérisées par le matériau, p. ex. alliages
• G21C 21/02 - Fabrication des éléments combustibles ou surrégénérateurs à l'intérieur de gaines non-actives
• B23K 9/028 - Soudage de joints continusSupportsPièces rapportées pour des joints curvilignes situés dans un plan
• B23K 9/16 - Soudage ou découpage à l'arc utilisant des gaz de protection
• G21C 3/10 - Obturateurs d'extrémités
• B23K 103/04 - Alliages d'acier
• B23K 101/14 - Échangeurs de chaleur

Abrégé

The invention relates to means for protecting the environment from the consequences of fires complicated by a radiation factor. A composition for dust suppression and containment of radioactive products of combustion after a fire with a radiation factor has been extinguished comprises, as a surface-active substance, a mixture of an anionic, a non-ionic and an amphoteric surface-active substance, and has the following ratio of components: 3.0-7.0 % by weight of an aqueous solution of polyvinyl alcohol (in terms of a mass fraction of dry product); 0.1-0.3 % by weight of plasticizer; 11.0-29.0 % by weight of surface-active substance; with water making up the remainder. The invention makes it possible to carry out dust suppression and containment of radioactive products of combustion which are formed on surfaces, including at elevated temperatures, after a fire has been extinguished.

Classes IPC  ?

• G21F 9/06 - Traitements
• G21F 9/28 - Traitement des solides
• G21F 9/12 - Traitements par absorptionTraitements par adsorptionTraitements par échange d'ions
• G21F 9/16 - Traitements par fixation dans un milieu solide stable

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for fastening a blanket module to the vacuum vessel of a fusion reactor. A device for fastening a blanket module to a fusion reactor vacuum vessel includes a support comprising flexible rod elements arranged in the form of a bundle between two flanges, in the central portion of the flanges. The support is connected by one flange to the blanket module and is mounted via the other flange in a threaded mounting seat in the vacuum vessel, wherein the support is connected to the seat by a threaded connection via a resilient clamping sleeve. The resilient clamping sleeve is mounted on the support such as to provide contact with the inner surface of the support flange facing the vacuum vessel. The diameter of the support flange facing the vacuum vessel and the diameter of the mounting seat are selected such that a radial compensating gap is formed between the flange and the mounting seat during mounting. The technical result of the present invention is that of providing plan view dual-axis tolerance during the installation of a blanket module on a vacuum vessel under the restricted conditions arising from the position of the mounting seat on the vacuum vessel by reducing the transverse dimension (in plan view) of the device and allowing free radial movement during the mounting of the support flange in the mounting seat in the fusion reactor vacuum vessel (prior to tightening).

Classes IPC  ?

• G21B 1/00 - Réacteurs de fusion thermonucléaire
• G21B 1/13 - Première paroiParoi de couvertureDivertor

Abrégé

The invention relates to the field of environmental protection, more specifically to the field of processing radioactive waste, and can be used for the safe and effective handling of a large quantity of liquid radioactive waste of various activity levels that has been formed as the result of decontaminating protective equipment of compartments and chambers, and makes it possible to decrease the volume of stored waste by solidifying same and incorporating same into a ceramic matrix. For this purpose, radioactive solutions after decontamination of surfaces of protective equipment are evaporated as alkaline and acidic solutions containing sodium hydroxide, potassium permanganate, oxalic acid, and nitric acid until a solid residue forms, and are calcined, and the calcinate is mixed with components of a fusion mixture containing oxides of titanium, calcium, iron (III), zirconium, and manganese (IV) and aluminum in a specified ratio, and fused.

Classes IPC  ?

• G21F 9/16 - Traitements par fixation dans un milieu solide stable

Abrégé

The invention relates to fuel assembly designs for nuclear reactors and can be used in fast neutron reactor cores. The technical result is more reliable spacing of a fuel element bundle in a fuel assembly and reduced local stress in the cladding of the fuel elements in the region where said elements are in contact with spacing elements. A fuel assembly comprises a top nozzle and a bottom nozzle which are connected to one another by a jacket; and a bundle of rod-type fuel elements arranged in the fuel assembly with the aid of a grid and spiral spacer elements wrapped around the cladding of each fuel element. The fuel assembly is characterized in that at least the peripheral fuel elements in a bundle are provided with spacer elements in the form of thin-walled tubes with longitudinal through slots, wherein the elements have a substantially oval cross section in the regions where they are in contact with the jacket. A method for producing a fuel assembly includes transversely compressing a fuel element bundle prior to placement in a jacket, whereby spacer elements of the peripheral fuel elements assume a substantially oval cross section in the regions where they are in contact with the jacket.

Classes IPC  ?

• G21C 3/32 - Faisceaux d'éléments combustibles en forme d'aiguilles, de barres ou de tubes parallèles

Abrégé

The invention relates to nuclear reactor protection systems and can be used when building nuclear reactors, in particular, the fast neutron reactors. The Technical result of the invention consists in the expansion of 5 functional capabilities of the negative reactivity passive insertion device by securing its reliable actuation in various emergency conditions. The device has two vessels located in a common enclosure one under another with a ring-shape hollow space between the vessels and the enclosure to let the heat carrier flow. Fuel elements are located in the ring-shape hollow space, as well as the tooling for the heat carrier flow formation to cool the fuel elements and heat the upper vessel. The upper vessel is located above the reactor core and is divided with an internal partition wall to the central cylindrical and ring-shape hollow spaces. The partition wall has low thermal conductivity in the transverse direction. In the central hollow space of the upper vessel the cadmium isotope is mainly located, while in its ring-shape space—mercury. Lower vessel is mainly located in the active core of the reactor and filled with inert gas. The vessels and are connected with a pipe with a partition, made in the form of buckling rapture disc.

Classes IPC  ?

• G21C 15/18 - Dispositions pour le refroidissement d'urgenceMise hors circuit de la chaleur
• G21C 7/22 - Commande de la réaction nucléaire par application de matériau absorbant les neutrons, c.-à-d. matériau avec section efficace d'absorption excédant largement la section efficace de réflexion par déplacement d'un matériau fluide ou fluent absorbant les neutrons
• G21C 9/033 - Moyens pour effectuer une réduction très rapide du facteur de réactivité dans des conditions défectueuses, p. ex. fusible pour réacteur par un fluide absorbant
• G21C 7/24 - Emploi de substances spécifiées pour utilisation comme matériau absorbant les neutrons
• G21C 3/326 - Faisceaux d'éléments combustibles en forme d'aiguilles, de barres ou de tubes parallèles comprenant des éléments combustibles de différentes compositionsFaisceaux d'éléments combustibles en forme d'aiguilles, de barres ou de tubes parallèles comprenant, en plus des éléments combustibles, d'autres éléments en forme d'aiguille, de barre ou de tube, p. ex. barres de commande, barres de support de grilles, barres fertiles, barres à poison ou barres factices

Abrégé

The invention relates to the field of radiation monitoring, specifically to a method for carrying out a search for and detection of gamma radiation sources. A method for searching for and detecting gamma radiation sources in conditions of nonuniform radioactive contamination additionally comprises stages in which a source of maximally active radiation is determined, the radiation power is measured with a collimated detector and at the same time the distance to the source is determined with the aid of a laser detector rangefinder, readings of the laser rangefinder and the value of a dose rate established by the detector are recorded, and, on the basis of the data produced, the dose rate of the radiation of the actual source is calculated, after which, in order to verify the distance measured to the radiation source, the aiming axis of the rangefinder is moved for a distance horizontally, the measurement is repeated and the distance recorded, the results of successive measurements of the distance are compared and, in the event of a divergence in the measurements within the laser rangefinder error limits, the information is acknowledged as reliable. The technical result consists in increasing the accuracy of measuring a distance to a gamma radiation source.

Classes IPC  ?

• G01T 1/167 - Mesure du contenu radioactif des objets, p. ex. contamination
• G01C 3/00 - Mesure des distances dans la ligne de viséeTélémètres optiques

Abrégé

The invention relates to thermonuclear engineering and is used in the production of tokamak thermonuclear power plants. A thermonuclear reactor comprises a vacuum casing and blanket modules connected thereto by means of flexible supports. The flexible supports additionally carry out functions of electrical connectors; moreover, the supports are formed from a material with high electrical conductivity. Each flexible support is secured at one end on the vacuum casing and at the other end on a blanket module; the two secured ends of each flexible support face the blanket module, and the actual flexible support is formed from two hollow cylindrical elements placed one in the other and perforated by longitudinal slots in a part free from mountings, and the ends of the hollow cylindrical elements opposite the secured ends are connected electrically and mechanically. The technical result consists in diverting eddy currents away from a blanket module of a thermonuclear reactor and simultaneously eliminating electrical connectors from the composition of a blanket and reducing sharp points on a blanket module side facing the vacuum casing.

Classes IPC  ?

• G21B 1/13 - Première paroiParoi de couvertureDivertor
• G21B 1/17 - Chambres à videInstallations de vide

Abrégé

The invention relates to multi-functional additives for a gaseous hydrocarbon fuel based on methane and other simple hydrocarbons, which improve the combustion characteristics of the fuel and thus also are better for the environment and increase fuel economy, and which also improve the fire safety of the fuel. A multi-functional additive for a gaseous hydrocarbon fuel based on methane and other simple hydrocarbons is comprised of trifluoromethane (CF3H) in an amount of up to 10 wt%.

Classes IPC  ?

• C10L 10/00 - Utilisation d'additifs à des fins particulières dans les combustibles ou les feux
• C10L 3/00 - Combustibles gazeuxGaz naturelGaz naturel de synthèse obtenu par des procédés non prévus dans les sous-classes , Gaz de pétrole liquéfié

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for electrically connecting components situated inside a nuclear fusion reactor chamber to the vacuum vessel of the reactor. A device for electrically connecting components situated inside a nuclear fusion reactor chamber to the vacuum vessel of the reactor comprises two identical stacks of electrically conductive plates. The electrically conductive plates are in the shape of a symmetrical wave having at least one full period. The plates in a stack are nested one inside another and are connected to flanges for attachment to a component situated inside the chamber and to the vacuum vessel. The stacks of electrically conductive plates are mounted with mirror symmetry about a line that passes through the centres of symmetry of the flanges. The technical result of the present invention is that of ensuring a practically identical skin effect on all of the electrically conductive plates of the device. In addition, the technical result is that of reducing the force of attraction between the outermost plates and the middle plates (the force of attraction between conductors carrying unidirectional currents), and providing uniform current density distribution in each electrically conductive plate.

Classes IPC  ?

• G21B 1/17 - Chambres à videInstallations de vide

Abrégé

The proposed invention relates to processes for extracting and concentrating radionuclides and can be used in radiochemical technologies when treating liquid radioactive waste. The method for isolating americium from liquid radioactive waste and for separating americium from rare earth elements in a single extraction cycle involves joint extraction of americium and rare earth elements from a nitric acid radioactive solution with a neutral solution of an organic extraction agent in a polar fluorinated solvent; washing an obtained organic phase saturated with metals; and selective back extraction of americium, wherein the extraction agent for joint extraction is N,N,N′,N′-tetraalkylamide of diglycolic acid, and a solution for back extraction is a composition of 5-20 g/l of a complexone, 5-60 g/l of a nitrogen-containing organic acid and 60-240 g/l of a salting-out agent.

Classes IPC  ?

• C22B 60/02 - Obtention du thorium, de l'uranium ou des autres actinides
• C22B 59/00 - Obtention des métaux des terres rares
• G21F 9/12 - Traitements par absorptionTraitements par adsorptionTraitements par échange d'ions
• C22B 7/00 - Mise en œuvre de matériaux autres que des minerais, p. ex. des rognures, pour produire des métaux non ferreux ou leurs composés
• C22B 3/32 - Acides carboxyliques

Abrégé

The invention relates to nuclear technology and may be used in preparing fuel rods and fuel assemblies for the cores of fast-neutron reactors utilizing a liquid-metal coolant. The technical result of the invention is to reduce the amount of metal consumed per fuel rod. In a fast-neutron reactor fuel rod (comprising nuclear fuel disposed in a sealed housing in the form of a thin-walled tubular steel shell and end parts, and a spacer element wound in a coil with a large pitch on the outside surface of the shell and fastened to the ends of the fuel rod on the end parts), the spacer element is in the form of a metallic band twisted about its longitudinal axis, the width of said band being approximately equal to the minimum distance between adjacent fuel rods in a fuel assembly of the nuclear reactor, the area of cross-section of the band being within a range of from 0.1 to 0.5 times the area of a circle described about said section.

Classes IPC  ?

• G21C 3/12 - Moyens formant partie de l'élément pour le positionner dans le cœur du réacteurEntretoises extérieures à cet effet
• G21C 3/338 - Éléments d'espacement hélicoïdaux

Abrégé

The invention relates to neutron radiography and can be used for the examination of elongate radioactive items, primarily nuclear fuel elements, and also for the non-destructive testing of irradiated and non-irradiated objects in order to determine the internal structure and material composition thereof. The present method consists in placing an object under examination into a protective container (3); placing the container on a bed (4) via a mounting seat (5) and rigidly securing the object therein; mounting, in a groove (8) in a limb (7), a first detector (11); setting an angle (+α) between the direction of radiation and the detector; supplying a neutron beam (1); mounting a second detector (12) in said groove; setting an angle (-α) between the direction of radiation and the detector; carrying out irradiation; and processing exposed films to obtain images at an angle of ±α. An apparatus for the implementation of a method for testing items, which comprises a source of neutrons, a protective container (3) and a detection system, additionally comprises a bed (4), having disposed thereon a detection system in the form of a rotatable limb (7) with a mounting seat (5) for securing neutron detectors (11, 12) in the form of a diametric groove (8), said limb being mounted such as to be rotatable by a set angle about an axis parallel to the axis of the object under examination, and having a semi-circular recess (13) therein for the passage of an elongate object as the limb rotates by an angle ±αi relative to the direction of a neutron beam (1).

Classes IPC  ?

• G01N 23/05 - Recherche ou analyse des matériaux par l'utilisation de rayonnement [ondes ou particules], p. ex. rayons X ou neutrons, non couvertes par les groupes , ou en transmettant la radiation à travers le matériau et formant des images des matériaux en utilisant des neutrons

Abrégé

The invention relates to the study and analysis of materials using electrical and magnetic instruments and can be used to determine the physical properties of superconductors. A device for determining the parameters of strip-type superconductors includes a generator, a frequency-setting element of the generator, an induction coil, connected to the generator, a receiver, a frequency-setting element of the receiver, and an induction coil connected to the receiver. The frequency-setting elements of the generator and the receiver are of the same type and have a narrow bandwidth. The frequency passbands of the frequency-setting elements of the generator and the receiver coincide no less than on half of the bandwidth of the frequency-setting element having the smaller passband. The generator and receiver induction coils are arranged with a gap therebetween, making it possible for a strip-type superconductor to be placed between the induction coils. The device is provided with a temperature gauge, for which purpose a thermistor, in contact with the superconductor, is used. The device ensures a high degree of accuracy and repeatability of measurement results.

Classes IPC  ?

• G01N 27/14 - Recherche ou analyse des matériaux par l'emploi de moyens électriques, électrochimiques ou magnétiques en recherchant l'impédance en recherchant la résistance d'un corps chauffé électriquement dépendant de variations de température

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for securing a blanket module to the vacuum vessel of a fusion reactor. A device for securing a blanket module to a fusion reactor vacuum vessel comprises a flexible support in the form of rods that are mounted between two flanges, a displacement compensator, and a threaded fastening member in the form of a locknut with a male thread. The displacement compensator is mounted on the flange of the flexible support which is oriented towards the module, said flange having a concave spherical surface, and is rigidly connected to the blanket module, wherein the displacement compensator comprises a locking screw and a supporting sleeve, which are pivotally interconnected, a spacer sleeve, and a coupling sleeve with a spherical protuberance. The spacer sleeve is movably connected to the locking screw and has a convex spherical surface and a concave spherical surface, which form a pivot connection to the flange of the support and to the spherical protuberance of the coupling sleeve respectively. The coupling sleeve is rigidly connected to a stop surface of the locknut. The technical result of the present invention is an increase in the permissible amount of tension force in the threaded joint between the flexible support and the module, which increases the load-bearing capacity of the device, prevents possible weakening of the threaded joint by virtue of self-locking ability, and provides for self-compensation of angular and axial displacements occurring as the module is mounted on the vacuum vessel.

Classes IPC  ?

• G21B 1/13 - Première paroiParoi de couvertureDivertor

Abrégé

The invention relates to the field of thermonuclear fusion and can be used in devices for electrically connecting elements inside a nuclear fusion reactor chamber to the vacuum vessel of the reactor. The present device for electrically connecting elements inside the chamber of a nuclear fusion reactor to the vacuum vessel of the reactor comprises laminar electrically conductive members, portions of the surface of which are oriented in different directions, said members being arranged in the form of a stack between flanges. The device is in the form of a single unit, in which shaped grooves are formed with connecting walls therebetween. The connecting walls constitute the electrically conductive members and grow broader in a profiled fashion between the differently oriented portions of the surface at the junction with the flanges provided on the end parts of the single unit. The technical result of the present invention is an increase in the cyclic strength of the electrically conductive members at the junctions between the members and the flanges and between the differently oriented portions of the surface (at bends) of the members. The invention also provides that the electrically conductive members have similar technical characteristics.

Classes IPC  ?

• H01R 4/58 - Connexions conductrices de l'électricité entre plusieurs organes conducteurs en contact direct, c.-à-d. se touchant l'un l'autreMoyens pour réaliser ou maintenir de tels contactsConnexions conductrices de l'électricité ayant plusieurs emplacements espacés de connexion pour les conducteurs et utilisant des organes de contact pénétrant dans l'isolation caractérisées par la forme ou le matériau des organes de contact
• G21B 1/17 - Chambres à videInstallations de vide

Abrégé

The invention relates to nuclear engineering and can be used in the manufacture of fuel elements for nuclear reactors. Essence of the invention: variants of a welded join between a fuel element casing and a plug which are made of high-chromium steel are proposed, providing for more reliable sealing of nuclear reactor fuel elements as a result of the production of a high quality welded join between the casing and the plug without the need for subsequent heat treatment of the weld seam, which simplifies the manufacturing process. This is achieved through the formation of a ferrite phase in the metal of the seam by adjusting the structure of a join between a casing and a plug made of ferrite-martensite and ferrite steels in different combinations and by observing the necessary size ratio parameters to ensure the formation of the aforesaid phase.

Classes IPC  ?

• B23K 31/02 - Procédés relevant de la présente sous-classe, spécialement adaptés à des objets ou des buts particuliers, mais non couverts par un seul des groupes principaux relatifs au brasage ou au soudage
• B23K 9/16 - Soudage ou découpage à l'arc utilisant des gaz de protection
• G21C 21/02 - Fabrication des éléments combustibles ou surrégénérateurs à l'intérieur de gaines non-actives
• G21C 3/04 - Détails de structure
• G21C 3/07 - EnveloppesChemises caractérisées par le matériau, p. ex. alliages
• B23K 101/04 - Objets tubulaires ou creux

Abrégé

The invention relates to nuclear engineering and can be used in the manufacture of fuel elements for nuclear reactors. Claimed is a method of sealing nuclear reactor fuel elements which includes welding one end of a casing with a plug, both being made of high-chromium steel, filling the fuel element with fuel, and welding a second plug to the other end of the casing. A casing made of a high-chromium ferrite-martensite steel and a plug made of a high-chromium ferrite steel are used. Argon arc welding is carried out at a volume ratio of the casing and plug materials contributing to the formation of the metal of the weld seam which permits the formation of a ferrite phase in said metal, wherein the ratio is: V1/V2 ≥18, where V1 is the volume of ferrite material and V2 is the volume of ferrite-martensite material. Argon arc welding is carried out at a current of 14-20 A, a speed of 12-15 m/h, an arc voltage of 9-10 W and an argon flow rate of 7-8 l/min. This provides for the necessary quality of the welded joins and simplifies the fuel element manufacturing process.

Classes IPC  ?

• G21C 21/02 - Fabrication des éléments combustibles ou surrégénérateurs à l'intérieur de gaines non-actives
• G21C 3/07 - EnveloppesChemises caractérisées par le matériau, p. ex. alliages
• G06F 17/30 - Recherche documentaire; Structures de bases de données à cet effet

Abrégé

The invention relates to nuclear technology and may be used in preparing fuel rods and fuel assemblies for the cores of fast neutron reactors utilizing a liquid-metal coolant. The technical result of the invention consists in reducing the metal content of a fuel rod, and in reducing the contact stresses occurring in a fuel rod casing in a reactor core during nuclear fuel burnup. . In the fast neutron reactor fuel rod (including nuclear fuel which is disposed in a hermetically-sealed container in the form of a thin-walled tubular casing made of steel and end components, and a spacing element which is wound in a wide-pitch spiral around the outer surface of the casing and which is secured, at the ends of the fuel rod, to the casing or to the end components), the spacing element is in the form of a thin-walled tube having a longitudinal through-slot along the length thereof. In accordance with the invention, the spacing element is made of a thin-walled tube or a thin band having a middle portion in the form of a tube with a longitudinal through-slot of a set width, and end components in the form of fragments of the cylindrical casing for welding to the casing or to fuel rod plugs.

Classes IPC  ?

• G21C 3/338 - Éléments d'espacement hélicoïdaux
• G21C 3/12 - Moyens formant partie de l'élément pour le positionner dans le cœur du réacteurEntretoises extérieures à cet effet

Abrégé

The invention relates to systems for protecting nuclear reactors and can be used in the production of nuclear reactors, in particular fast reactors. The technical result of the invention consists in extending the functional possibilities of a device for the passive introduction of negative reactivity by providing for reliable operation of said device in various emergency modes. The device is in the form of two vessels which are arranged one above the other in a common casing, an annular cavity being formed between the vessels and the casing for the flow of a heat transfer agent. Fuel elements and also means for generating flows of heat transfer agent for cooling the fuel elements and for heating the upper vessel are disposed in the annular cavity. The upper vessel is arranged above the reactor core and is divided by an internal partition into a central cylindrical cavity and an annular cavity. The partition has low heat conductivity in the transverse direction. A cadmium isotope is preferably disposed in the central cavity of the upper vessel, and mercury in the annular cavity thereof. The lower vessel is substantially disposed in the reactor core and is filled with an inert gas. The vessels are connected to each other by a pipe with a partition which is in the form of a buckling rupture diaphragm.

Classes IPC  ?

• G21C 9/033 - Moyens pour effectuer une réduction très rapide du facteur de réactivité dans des conditions défectueuses, p. ex. fusible pour réacteur par un fluide absorbant
• G21C 7/22 - Commande de la réaction nucléaire par application de matériau absorbant les neutrons, c.-à-d. matériau avec section efficace d'absorption excédant largement la section efficace de réflexion par déplacement d'un matériau fluide ou fluent absorbant les neutrons

Abrégé

An active zone includes a homogeneous uranium-plutonium nitride fuel, the mass fraction of which is a minimum 0.305, and consists of central, intermediate and peripheral parts which form fuel assemblies comprising fuel elements with geometrically identical shells but differing heights. The radial distribution of the fuel across the volume of the active zone has a stepped shape. The radius of the central part is from 0.4 to 0.5 of the effective active zone radius, while the height of the fuel column in the fuel elements in the central part is from 0.5 to 0.8 of the height of the fuel column in the peripheral part. The heights of the fuel columns forming a stepped intermediate part for diameters ranging from 0.5 to 0.85 of the effective active zone diameter are within the range from 0.55 to 0.9 of the height of the fuel column in the peripheral part.

Classes IPC  ?

• G21C 1/02 - Réacteurs de fission rapides, c.-à-d. réacteurs n'utilisant pas de modérateur
• G21C 3/04 - Détails de structure
• G21C 3/42 - Emploi de substances spécifiées comme combustibles pour réacteurs
• G21C 5/14 - Structure du modérateur ou du cœurEmploi de matériaux spécifiés comme modérateur caractérisée par la forme
• G21C 3/58 - Combustible pour réacteur solide

Abrégé

The proposed invention relates to processes for extracting and concentrating radionuclides and can be used in radiochemical technologies when treating liquid radioactive waste. The method for isolating americium from liquid radioactive waste and for separating americium from rare earth elements involves joint extraction of americium and rare earth elements from a nitric acid radioactive solution by means of a solution of a neutral organic extraction agent in a polar fluoroorganic solvent; washing of an organic phase saturated with metals; and selective re-extraction of americium, wherein N,N,N',N'-tetraalkylamide of diglycolic acid is used as the extraction agent, and a solution having a composition of 5-20 g/l complexon, 5-60 g/l nitrogen-containing organic acid and 60-240 g/l salting-out agent is used as the solution for re-extraction of americium. The technical result is the isolation of americium from liquid acid radioactive solutions and the separation of americium from all the rare earth elements in a single extraction cycle.

Classes IPC  ?

• C22B 60/02 - Obtention du thorium, de l'uranium ou des autres actinides
• C22B 59/00 - Obtention des métaux des terres rares
• C22B 3/26 - Traitement ou purification de solutions, p. ex. de solutions obtenues par lixiviation par extraction liquide-liquide utilisant des composés organiques
• C22B 7/00 - Mise en œuvre de matériaux autres que des minerais, p. ex. des rognures, pour produire des métaux non ferreux ou leurs composés

Abrégé

The invention relates to nuclear technology and is intended for use in power-generating systems with a fast reactor cooled by a liquid-metal coolant which is primarily in the form of molten lead or an alloy thereof. The problem addressed by the invention consists in reducing the specific volume of lead coolant per unit of power of the reactor and in increasing the safety of the reactor. The system comprises a reactor cavity (1) with an upper cover (2), which is arranged in the reactor cavity (1) with an active zone (4), steam generators (5), circulation pumps (7), circulation conduits (8) and (9), actuating mechanism systems and devices for starting up, operating and shutting down the reactor system, wherein the steam generators (5) are in the form of tubular heat exchangers in which the lead coolant (10) flows within pipes, while the water steam flows in a space between the pipes, the steam generators (5) are arranged in separate boxes (6) and communicate with the reactor cavity (1) by means of circulation conduits for raising (8) and discharging (9) the lead coolant (10), the steam generators (5) and a large portion of the circulation conduits (8) and (9) are arranged higher than the level of the lead coolant (10) in the reactor cavity (1), and the circulation pumps (7) are arranged in the reactor cavity (1) on the circulation conduits (8) and (9) for raising the "hot" lead coolant, and a technical means (13) is provided for ensuring intrinsic circulation of the lead coolant (10) through the active zone (4) of the reactor when the circulation pumps (7) are switched off.

Classes IPC  ?

• G21C 1/03 - Réacteurs de fission rapides, c.-à-d. réacteurs n'utilisant pas de modérateur refroidis par un réfrigérant non nécessairement pressurisé, p. ex. réacteurs du type piscine

Abrégé

The active zone of a reactor, a fuel element and a fuel assembly for creating said active zone are intended for use in fast reactors with a nitride fuel and a liquid-metal coolant primarily in the form of molten lead and alloys thereof. The problem addressed by the invention consists in creating an active zone with a negative vacuum reactivity effect and with effective levelling out of the power density along the radius of the active zone. The active zone comprises a homogeneous uranium-plutonium nitride fuel, the mass fraction of which in the active zone is a minimum of 0.305, and consists of 3 parts - a central part, an intermediate part and a peripheral part, which form fuel assemblies comprising fuel elements with geometrically identical shells, but with a differing height of the fuel column in the central part, the intermediate part and the peripheral part of the active zone, wherein the radial distribution of the fuel along the volume of the active zone is characterized by a stepped shape in longitudinal section. The radius of the central part of the active zone is from 0.4 to 0.5 of the effective radius of the active zone, while the height of the fuel column in the fuel elements of the fuel assemblies in the central part is from 0.5 to 0.8 of the height of the fuel column in the fuel elements arranged in the fuel assemblies in the peripheral part of the active zone. The heights of the fuel columns forming a stepped intermediate part (with at least one step) for diameters lying within the range of from 0.5 to 0.85 of the effective diameter of the active zone are selected within the range of from 0.55 to 0.9 of the height of the fuel column in fuel elements arranged in the fuel assemblies in the peripheral part of the active zone.

Classes IPC  ?

• G21C 1/02 - Réacteurs de fission rapides, c.-à-d. réacteurs n'utilisant pas de modérateur