123results about "Fuel element assemblies" patented technology

The invention provides a nuclear fuel grillwork clamping device and a vibration acceleration control method, and relates to the technical field of nuclear fuel grillwork clamping devices.The nuclear fuel grillwork clamping device comprises the steps that a plurality of clamping pieces are slidably installed in a nuclear reaction box body in the first direction and connected with the multiple clamping pieces at the same time through a transmission mechanism, and the clamping pieces are connected with the nuclear reaction box body through the structural characteristics of the transmission mechanism; and the plurality of clamping pieces are enabled to vibrate in two opposite directions of the first direction. Based on the structural design, the mode that the clamping pieces are installed in the nuclear reaction box body is changed into sliding connection from fixed connection, and the multiple clamping pieces are connected at the same time through the transmission mechanism. In the nuclear reaction process, the transmission effect of the transmission mechanism can be utilized to enable the plurality of nuclear fuel grillages to vibrate along opposite directions; therefore, the vibration amplitude of the nuclear fuel grillwork is reduced, and finally the purpose of reducing the failure rate of the nuclear fuel grillwork is achieved.

The invention discloses an assembly method of a heat pipe type reactor and the heat pipe type reactor, and belongs to the field of nuclear power. The assembly method of the heat pipe type reactor comprises the following steps: closing one end of each mounting hole of the grid base body, vertically arranging the grid base body to enable the closed end to be located at the bottom, injecting filling slurry containing heat-conducting powder and a dispersing agent into the mounting holes, then inserting pipe fittings into the mounting holes until the filling slurry overflows, and finally assembling the grid base body into the mounting holes. The gap between the pipe fitting and the mounting hole is uniformly filled with the filling slurry in a forced flowing mode; and heating to cure and shape the filling slurry. The method can effectively eliminate the assembly gap between the grid substrate and the pipe fitting of the heat pipe type reactor, and improves the heat transfer efficiency and the safety margin of the reactor.

Carbide-based fuel assembly includes outer structural member of ceramic matrix composite material, the interior surface of which is lined in higher temperature regions with an insulation layer of porous refractory ceramic material. A continuous insulation layer extends the length of the fuel assembly or separate insulation layer sections have a thickness increasing step-wise along the length of the fuel assembly from upper (inlet) section towards bottom (outlet) section. Fuel element positioned inward of the insulation layer and between support meshes has a fuel composition including HALEU and the form of a plurality of individual elongated fuel bodies or one or more fuel monolith bodies containing coolant flow channels. Fuel assemblies are distributively arranged in a moderator block, with upper end of the outer structural member attached to an inlet for propellant and lower end of the outer structural member operatively interfaced with a nozzle forming a nuclear thermal propulsion reactor.

The invention provides a reactor internal capable of realizing integral movement of a reactor core, and relates to the technical field of research, development and design of reactor body structures, the reactor internal comprises a hanging basket barrel, a reactor core shroud and a reactor core; the reactor core is arranged in the reactor core shroud; the reactor core shroud is arranged in the hanging basket barrel body, the reactor core shroud is movably connected with the hanging basket barrel body, the reactor core shroud slides up and down in the hanging basket barrel body, and the bottom of the hanging basket barrel body supports the reactor core shroud. According to the invention, the material changing and maintenance efficiency can be effectively improved, the downtime is shortened, the safety is enhanced, the personnel radiation exposure risk is reduced, the inspection and maintenance are convenient, and the service life of equipment is prolonged. The system adapts to advanced reactor design and conforms to the development trend of modularization and high efficiency, and the performance, safety and economical efficiency of the nuclear reactor are remarkably improved through the design of the system.

The utility model belongs to the technical field of fuel elements for nuclear reactors, and discloses a guide pipe, a guide pipe assembly and a pressurized water reactor fuel assembly. The guide pipe comprises a pipe body and two water hole assemblies, the pipe body is oppositely provided with a first end and a second end in the axial direction of the pipe body, the two water hole assemblies are arranged at the position, close to the first end, of the pipe body and the position, close to the second end, of the pipe body respectively, and the two water hole assemblies are symmetrically arranged in the radial direction of the center of the pipe body; the water hole assemblies are arranged at the two ends of the pipe body in the axial direction of the pipe body and used for discharging water flow during rod falling, that is, the pipe body has a mistake-proof function, so that when the guide pipe is installed, whether the guide pipe and the end plug are installed reversely or not does not need to be considered, the problems that the guide pipe assembly, a framework and a pressurized water reactor fuel assembly are scrapped and the like are avoided, and the production efficiency is improved. The installation reliability of the guide pipe is improved, and the safety of the pressurized water reactor fuel assembly loaded with the guide pipe is further improved.

A fuel assembly comprises a fuel assembly intermediate structure 250 circumferentially enclosing an interior volume, a fuel element bundle 190 located within the interior volume with the fuel assembly intermediate structure radially outward of the fuel element bundle, an insulation layer 160 radially outward of the fuel assembly intermediate structure 250, a void space 255 between an inner surface of the insulation layer 160 and an outer surface of the fuel assembly intermediate structure 250, a fuel assembly outer structure 110 radially outward of the insulation layer 160, and a second void space 265 between an outer surface of the insulation layer 160 and an inner surface of the fuel assembly outer structure 110. The fuel element bundle includes a plurality of fuel elements 105 and a coolant flow volume 115, through which a coolant in a form of a propellant gas flows during operation of a reactor containing the fuel assembly, so that the coolant contacts exterior surfaces of the fuel elements 105.

The embodiment of the invention relates to assembling equipment of a reactor fuel element, in particular to sodium bonding equipment of a metal fuel rod. The sodium binding equipment comprises a fuel rod supporting frame, a heating device and an impact device. A plurality of containing grooves are formed in the fuel rod supporting frame, and each containing groove is used for containing a metal fuel rod. A heating cavity is formed in the heating device, the fuel rod supporting frame is partially contained in the heating cavity, and the heating device is used for heating the metal fuel rod, so that solid sodium in the metal fuel rod is melted into liquid sodium. The impact device is arranged to impact the fuel rod supporting frame upwards, and when the impact device impacts the fuel rod supporting frame, an axial impact load and a tangential impact load are generated, so that the metal fuel rod freely falls after rising, and meanwhile, the metal fuel rod rotates and deviates in the tangential direction to eliminate the defects in the liquid sodium.

Fuel bundle has plurality of twisted ribbon fuel rodlets in hexagonal packing or circle packing arrangement in a core region encased in a multilayer casing. Arrangement of twisted ribbon fuel rodlets is facilitated by rodlet seating fixture with seating surface having a plurality of protrusions that form a receiving space for ends of the twisted ribbon fuel rodlets. Manufacture of the fuel bundle incorporates fiber manufacturing technologies and, optionally, infiltration of void spaces in core region by infiltrant. Twisted ribbon fuel rodlet manufacturing system has sub-systems that impart twist periodicity to extruded ribbons, inspect twisted extruded ribbons, and cut twisted extruded ribbons to length. Inspection sorts twisted ribbon fuel rodlets as well as provides feedback to adjust operation of sub-systems. The fuel bundle (and optional fuel bundle support) can be incorporated into a fuel assembly of a nuclear propulsion fission reactor structure of, for example, a nuclear thermal propulsion engine.

The invention belongs to the technical field of nuclear reactor cores, and particularly relates to a fast thermal coupling metal hydride reactor core controlled by a rotating drum and a rotating drum control method, and the reactor core comprises the rotating drum, a reactor core active area, a coolant flow channel, a beryllium oxide reflecting layer and a thermal insulation shielding layer; the coolant flow channel is composed of a coolant flow channel inner barrel and a coolant flow channel outer barrel; the reactor core active area is wrapped by the coolant flow channel inner barrel, and oxide fuel rods and metal hydride fuel rods are arranged in the reactor core active area; the beryllium oxide reflecting layer is arranged on the coolant flow channel outer barrel in a sleeving manner, and the heat preservation shielding layer is arranged on the beryllium oxide reflecting layer in a sleeving manner; a plurality of rotating drums are arranged between the beryllium oxide reflecting layer and the heat preservation shielding layer in the circumferential direction. The oxide fuel rods and the metal hydride fuel rods are arranged in the reactor core active area at the same time, so that the fast thermal coupling design of a reactor core neutron energy spectrum is realized, and the reactivity control value of the rotating drum is improved.

We provide a mandrel-wound, splined, monolithic fuel assembly core. [Solution] The fuel assembly core comprises a channel, a fuel monolith containing fissile fuel components and axially arranged, an exhaust support plate, an exhaust shield assembly, and an insulating layer. The fuel monolith has an eccentric cylindrical or straight cylindrical shape with a side surface keyway. The channel in the exhaust support plate is oriented so that the propellant gas does not collide with the exhaust shield assembly. The fuel assembly core is manufactured by forming a fuel monolith stack mandrel assembly and mandrel winding an insulating layer onto the outer surface of the tensioned fuel monolith stack mandrel assembly. The fuel assembly core is incorporated into the fuel assembly of a nuclear propulsion fission reactor structure (e.g., a nuclear thermal propulsion engine).

The reactor core comprises a plurality of core assemblies. The plurality of core assemblies have a cooperative structure formed on one or more load pads that mechanically connects the plurality of core assemblies to each other and restricts the relative motion between the core assemblies in a kinematically determined manner. A shear key on one core assembly is configured to fit into a tab slot on an adjacent core assembly. The motion of one core assembly is transmitted to a second core assembly, and these core assemblies move together.

Systems and methods use inserted controllers in assembly openings of nuclear fuel castings. The controllers can be secured entirely within the opening and condition coolant flow to a desired level for the associated assembly. The controllers can be installed or removed at any time through clamps or other securing structures accessible through the top of the opening. This may include during fuel removal or shuffling during a maintenance outage, or at casting construction and installation, or at decommissioning. Side orifices do not have to be accessed from below the core nor do the castings otherwise require movement or alteration. Any desired flow characteristics may be selected and achieved through use of the configured controllers at specific core locations. Size, shape, and flow surfaces can all be configured to achieve these characteristics where they permit the controller to fit in the casting.

A nuclear fuel assembly and a method of manufacture thereof are provided. The method comprises depositing a thermally conductive layer onto at least a portion of at least two nuclear fuel layers to create at least two at least partially coated layers. The method comprises stacking the at least two coated layers and bonding the at least two coated layers to form a nuclear fuel assembly.

The invention provides a nuclear fuel grillwork splicing automatic alignment device and a control method, and the method comprises the steps: installing a plurality of first grillwork strips on an adjusting assembly, and enabling the plurality of first grillwork strips to be perpendicular to a first direction; detecting relative positions of the first grillwork strip and the second grillwork strip through a binocular camera and a processor; and then the adjusting assembly is used for driving the multiple first grillwork strips to move in the second direction perpendicular to the first direction, so that the multiple first opening gaps in the multiple first grillwork strips are aligned in the first direction. And finally, the splicing assembly is used for clamping the second grillwork strip to complete splicing. Based on the nuclear fuel grillwork splicing automatic alignment device, whether the first grillwork strips are aligned or not can be automatically detected before splicing; and when alignment is not carried out, automatic adjustment and alignment can be carried out, and finally the splicing process is completed. Therefore, the problem that the grillage strips are difficult to align in the splicing process is solved, the splicing efficiency is improved, and it is guaranteed that damage cannot be caused in the splicing process.

The application provides a fuel rod bundle automatic assembling device, which comprises a truss, a feeding mechanism, a pre-positioning mechanism, an assembling mechanism and a workbench, the pre-positioning mechanism is arranged on the workbench, and a vertical grid plate and a rod box for containing fuel rods are further fixed on the workbench, the rod box, the pre-positioning mechanism and the grid plate are arranged side by side, the feeding mechanism is movably connected to the truss and is used for moving the fuel rods in the rod box to the pre-positioning mechanism, the pre-positioning mechanism is arranged on the workbench and is used for axially and circumferentially positioning the fuel rods, so that the through slot on the end plug of the fuel rod is vertically arranged and corresponds to the insertion part of the grid plate on the workbench, and the assembling mechanism is movably connected to the truss and is used for moving the fuel rods positioned on the pre-positioning mechanism to the grid plate, so that the fuel rods and the grid plate are inserted through the through slot and the insertion part. The application can realize the automation and intelligentization of the rod bundle assembling process, so as to improve the automatic assembling efficiency of the rod bundle.

A filter for separating debris from a cooling liquid in a nuclear plant includes a passage with an inner surface, an inlet end and an outlet end. The passage is configured to permit through-flow of the cooling liquid in a main flow direction from the inlet end to the outlet end for a cooling purpose. The inner surface of the passage includes at least one surface portion facing a sub flow direction of the cooling liquid and includes a surface irregularity configured to catch the debris flowing in the cooling liquid in the sub flow direction during lifting or transportation of the filter after the filter has been used for separating debris from the cooling liquid in the nuclear plant wherein the sub flow direction is the opposite direction to the main flow direction. A fuel assembly for a nuclear plant, comprising a filter is also described.

A nuclear fuel assembly and a method of manufacture thereof are provided. The method comprises depositing a thermally conductive layer onto at least a portion of at least two nuclear fuel layers to create at least two at least partially coated layers. The method comprises stacking the at least two coated layers and bonding the at least two coated layers to form a nuclear fuel assembly.

The invention relates to the technical field of nuclear fuel assembly design, and particularly discloses a foreign matter capturing unit, a foreign matter capturing structure and a nuclear fuel lower pipe seat, the foreign matter capturing unit comprises a separation plate, and a lower guide seat and an upper guide seat which are respectively fixed at the lower end and the upper end of the separation plate; the separating plate is vertically arranged, the two sides of the lower guide base extend outwards to form a lower base outer arc guide face and a lower base inner arc guide face respectively, and the two sides of the upper guide base extend outwards to form an upper base inner arc guide face and an upper base outer arc guide face respectively. A first foreign matter capturing space is defined by the lower base outer arc guide face, the separation plate and the lower guide base. The guide surface of the foreign matter capturing unit adopts the arc-shaped upstream face, so that the local hydraulic loss in the coolant circulation process is effectively reduced, and a better coolant flow field is ensured.

A fuel assembly for use in a nuclear reactor comprising a fuel bundle, a plenum header connection positioned on the fuel bundle, a mast extending from the fuel bundle, and a common fission gas plenum extending from the mast is disclosed. The reactor includes a vessel and coolant situated within the vessel. The fuel bundle comprises a plurality of fuel elements including nuclear fuel material positioned therein. The plenum header connection comprises a plurality of passageways defined therein that are in fluid communication with the nuclear fuel material. The elongate mast comprises an internal passage connecting the common fission gas plenum to the plurality of passageways of the plenum header connection such that the common fission gas plenum is configured to receive an amount of fission gas generated by the nuclear fuel material during operation. The common fission gas plenum is positioned in an otherwise unused portion of the vessel.

The application relates to an experimental device for studying the accident failure behavior of a nuclear reactor fuel rod bundle, comprising a high-temperature heating furnace, a fuel rod bundle and auxiliary equipment, the fuel rod bundle is composed of multiple fuel rods, the fuel rod bundle penetrates through the high-temperature heating furnace along the channel axis, the multiple fuel rods are arranged in a 5*5 matrix, including 20 heating rods, 1 non-heating rod and 4 corner rods, wherein the 1 non-heating rod is located at the center, and the 4 corner rods are located at the four corners of the matrix; electrodes are arranged at the two ends of the fuel rod bundle to heat the fuel rod bundle. The auxiliary equipment simulates the environment of the fuel rod bundle in the high-temperature heating furnace, so that the oxidation, expansion and failure states and data of the fuel rod bundle under different environments are obtained. Through the arrangement of the 25 fuel rods, the application can carry out fuel rod bundle experiments under the influence of factors such as flow channel blockage between the fuel rod bundles, rod extrusion, inter-rod thermal radiation and axial temperature difference under the influence of oxidation, expansion and failure mechanisms.

The application provides a mixing wing, a positioning grid, a fuel assembly and a preparation method, and relates to the technical field of nuclear reactions. The mixing wing is applied to the positioning grid of the fuel assembly, and the mixing wing is a shape memory alloy with double-path memory effect. The positioning grid comprises a grid body and the mixing wing, and the mixing wing is arranged on the end face of the grid body. The fuel assembly comprises a fuel rod bundle and the positioning grid, and a plurality of fuel rods of the fuel rod bundle correspondingly pass through a plurality of through holes of the positioning grid. The preparation method is used for preparing the positioning grid. The mixing wing is made of the shape memory alloy with double-path memory effect, the shape of the mixing wing can be self-adaptively adjusted according to the change of the reactor working condition and is located at different positions, different degrees of transverse disturbance flow of the coolant in the sub-channel of the fuel assembly rod bundle are generated, the best distribution of the bubble and the liquid film on the inner wall of the sub-channel of the fuel assembly rod bundle under different reactor working conditions is maintained, and therefore the economy and the safety of the fuel assembly are improved.

The present invention provides a nuclear fission reactor structure and a method for manufacturing the same that comply with neutron engineering and thermal management requirements for nuclear fission reactors, while reducing manufacturing complexity and variability. [Solution] Multiple layers form a nuclear fission reactor structure. Each layer has an inner segment body, an intermediate segment body, and an outer segment body (each segment body is separated by a contact surface). The layer includes multiple cladding arms having an involute curve shape that radiates outward in a helical manner from the radially inner end to the radially outer end. The chambers of the involute curve cladding arms contain the fuel composition (and / or other materials such as moderators and interfering materials).

The invention discloses a fuel rod pulling device and a rod pulling method thereof, and the fuel rod pulling device is used for installing a fuel rod into a positioning grid. The connecting pipe assemblies are used for isolating fuel rods from transverse rigid protrusions of the positioning grillwork, the telescopic driving assemblies are arranged corresponding to the connecting pipe assemblies and used for driving the connecting pipe assemblies to move horizontally, and the rod pulling machine is used for installing the fuel rods into the positioning grillwork. According to the fuel rod pulling device, the fuel rods and the transverse rigid protrusions of the positioning grillwork can be isolated through the arrangement of the connecting pipe assemblies, direct friction and extrusion between the fuel rods and the transverse rigid protrusions are avoided fundamentally, zirconium chips are greatly reduced, meanwhile, scratches on the surfaces of the fuel rods are avoided, and the reliability of safe operation in a fuel assembly reactor is improved. And the telescopic driving assembly can accurately drive the connecting pipe assembly to complete loading and extraction actions, the operation process of existing rod pulling equipment is adapted, large-scale transformation of the existing equipment is not needed, and the practicability is high.

The fuel assembly includes a base material formed of a zirconium alloy and a coating layer, and the coating layer includes a chromium layer formed of chromium or a chromium alloy and a corrosion-resistant layer formed of zirconium alloy or a titanium alloy. The method for producing a fuel assembly includes a step of preparing the base material, a step of forming the chromium layer on a surface of the base material that would otherwise be in contact with cooling water, a step of forming the corrosion-resistant layer on a surface of the chromium layer, and a step of assembling the fuel assembly using the base material. The chromium layer and the corrosion-resistant layer are formed according to a thin plate cladding method, a physical vapor deposition method, a thermal spraying method, a cold spraying method, or a plating method before the assembling using the base material.

Thorium-based fuel bundles are used in existing PHWR reactors (e.g., Indian 220 MWe PHWR, Indian 540 MWe PHWR, Indian 700 MWe PHWR, CANDU 300 / 600 / 900) in place of conventional uranium-based fuel bundles, with little or no modifications to the reactor. The fuel composition of such bundles is 60+ wt % thorium, with the balance of fuel provided by low-enriched uranium (LEU), which has been enriched to 13-19.95% 235U. According to various embodiments, the use of such thorium-based fuel bundles provides (1) 100% of the nominal power over the entire life cycle of the core, (2) high burnup, and (3) non-proliferative spent fuel bundles having a total isotopic uranium concentration of less than 12 wt%. Reprocessing of spent fuel bundles is also avoided.

According to an aspect, there is provided an end fitting for reducing hydrogen transfer to a pressure tube of a nuclear reactor across a rolled joint. The end fitting includes a barrier disposed along at least a portion of an internal diameter of the end fitting configured to contact coolant. According to an aspect, there is provided a method of reducing the transfer of hydrogen to a pressure tube of a nuclear reactor across a rolled joint. The method includes providing an end fitting including a barrier disposed along at least a portion of an internal diameter of the end fitting configured to contact coolant, and burning fuel in a nuclear reactor.

The invention relates to the technical field of nuclear reactor cores, and particularly provides a reactor core with mixed arrangement of metal hydride fuel and metal fuel, which comprises a plurality of fuel assemblies, any fuel assembly comprises a metal hydride fuel rod loaded with metal hydride fuel and a metal fuel rod loaded with metal fuel; and in any one of the fuel assemblies, the proportion of the metal hydride fuel rods is 0-100%. The high uranium density and high proliferation characteristics of metal fuel and the hydrogen atom moderation characteristic of metal hydride fuel are utilized, the metal fuel and the metal hydride fuel are arranged in a mixed mode, meanwhile, the proportion of the metal hydride fuel and the metal fuel is adjusted according to the reactor core power life period and other design requirements, and customized adjustment of the reactor core energy spectrum is achieved; and the performance of the reactor core is optimized to meet the requirements of different application scenes.

A nuclear fuel assembly comprises nuclear fuel rods (4) extending along a longitudinal axis (L) and a support skeleton (6) configured to support the nuclear fuel rods (4). The support skeleton (6) includes two end pieces (8, 10), a plurality of guide tubes (12) connecting the end pieces (8, 10) to each other, and spacer grids (14) attached to the guide tubes (12), with each spacer grid (14) supporting the nuclear fuel rods (4). The nuclear fuel assembly further includes at least one reinforcement device (20) comprising at least one reinforcement plate (22) which is in contact with at least two of the guide tubes (12) and attached to one or more of the guide tubes (12) at attachment points (21). Each reinforcement plate (22) has at least two attachment points (21) that are offset relative to each other along the longitudinal axis (L).

The application discloses a spliced fuel assembly structure and a reactor core, which can connect integrated channels of two fuel assembly bodies through a connecting sleeve, and reduces the leakage problem caused by the flow of coolant between the two fuel assembly bodies. The spliced fuel assembly structure comprises the fuel assembly bodies and the connecting sleeve. The number of the fuel assembly bodies is two; the fuel assembly bodies are internally provided with the integrated channels, the integrated channels are arranged along the axial direction of the fuel assembly bodies, and the integrated channels are used for guiding the coolant; the two fuel assembly bodies are oppositely arranged along the axial direction, and the two fuel assembly bodies are both provided with positioning holes on the two opposite end faces, and the positioning holes are communicated with the integrated channels in the corresponding fuel assembly bodies. The two ends of the connecting sleeve are matched with the two positioning holes, and the two ends of the connecting sleeve are respectively inserted into the two positioning holes; the connecting sleeve is internally provided with a communicating hole, and the communicating hole is communicated with the integrated channels of the two fuel assembly bodies, so that the coolant can flow in the two fuel assembly bodies.

A nuclear reactor is designed and constructed to withstand seismic events. A mechanical hold down and discriminator may be provided as cooperating structure between the core receptacle and a nozzle of a core assembly. One or more receivers may be formed on the nozzle that cooperate with corresponding protrusions in a core receptacle. As the nozzle is inserted into the receptacle, the protrusion engages with the receiver to inhibit unintentional withdrawal of the nozzle from the receiver. A first pattern of receivers on a nozzle may align with a first pattern of protrusions within a receptacle to enable the nozzle to fit within a first receptacle. A second pattern of receivers formed on a second nozzle may inhibit the second nozzle from being inserted into the first receptacle and thereby provide a discrimination feature to ensure proper core assemblies are located in the correct location within a nuclear reactor core.