112 results about "Nuclear fuel" patented technology

The application discloses an accident-tolerant nuclear fuel cladding coating and a preparation method and application thereof, and belongs to the technical field of nuclear fuel cladding coating. The coating is a Cr-based binary alloy coating deposited on the surface of a zirconium alloy base, and is selected from Cr-Fe, Cr-V or Cr-Mo alloy coatings, wherein the content of Fe is 3-10 wt%, the content of V is 3-20 wt%, and the content of Mo is 1-5 wt%. The preparation method adopts a magnetron sputtering process, and is realized by controlling parameters such as vacuum degree, temperature, gas pressure, bias voltage and power. Through alloying, the application effectively inhibits the element interdiffusion between the coating and the zirconium alloy base at high temperature, reduces the formation of brittle intermetallic compounds and Kirkendall holes, significantly improves the thermal stability and service life of the coating under accident conditions, meanwhile, the process is mature, the coating quality is high, and the coating is suitable for surface protection of zirconium alloy fuel cladding of nuclear power stations.

The application relates to the technical field of nuclear fuel assembly manufacturing, and particularly discloses a nuclear fuel assembly casting type upper tube seat machining clamp and a machining method, wherein the tube seat blank is placed on a bottom plate, a positioning top block is pushed, four positioning pins below a positioning push rod are centered with positioning holes of the tube seat blank; then a positioning rod B is screwed to shorten the distance with a positioning rod A; then locking screws and fastening bolts on the edge frame of a positioning frame plate are locked to fix the tube seat blank on the bottom plate, positioning is realized; finally, the positioning rod B is completely screwed out of the positioning rod A, the bottom plate, the positioning frame plate and the tube seat blank are integrally taken out and fixed on a machining equipment. The machining clamp and the machining method satisfy the positioning clamping and machining requirements of the casting type upper tube seat, the upper tube seat after machining completely satisfies the drawing and technical condition requirements, and the machining scheme satisfies the engineering production.

The application relates to the technical field of fuel assembly transportation devices and discloses a nuclear fuel assembly transportation container hook locking device which comprises connecting pieces fixed on a fuel assembly transportation container and arranged adjacently on the same side, a limiting piece, and a lock hook piece pivotally connected to the connecting pieces and detachably connected with the limiting piece; the limiting piece is provided with a limiting groove and a locking mechanism, the locking mechanism comprises a lock tongue; the lock hook piece is provided with a hooking part which can be inserted into the limiting groove and hooked to a movable door assembly; when the lock tongue is subjected to a preset size of thrust of the hooking part, the lock tongue exits the limiting groove; when the hooking part is inserted into a set position of the limiting groove, the lock tongue extends into the limiting groove and stops the hooking part. The application has the limiting effect on the circumferential freedom of the movable door assembly, solves the constraint problem of the movable door assembly during fuel assembly loading and unloading, improves the stability of the fuel assembly transportation container, and has the advantages of simple structure, convenient operation and easy maintenance.

The invention relates to the field of nuclear fuel element manufacturing, in particular to a material boat in-place sensor and a high-temperature continuous sintering furnace. According to the material boat in-place sensor, a spiral spring and a probe piston are arranged in a shell, one end of a contact probe is located in the shell, and the other end of the contact probe penetrates out of the shell; the probe piston slides in the shell and is in contact with the probe piston when sliding to the end part; a piston rod of the probe piston is sleeved with the spiral spring, the tail cover is screwed on the shell through threads, a through hole is formed in the center of the tail cover, and hole threads are arranged on the inner side of the through hole. The pre-tightening nut is assembled on a hole thread on one side of the tail cover, the depth of the pre-tightening nut is adjusted through the thread, and then the initial elastic force of the spiral spring is adjusted. The contact type sensor is assembled on a hole thread on the other side of the tail cover; after the contact probe is triggered, the contact probe moves towards the probe piston and contacts with the probe piston, the spiral spring is compressed, the probe piston is pushed towards the direction of the contact type sensor, and then the contact type sensor is started to generate a control signal. And the material boat in-place sensor is integrally sealed. The material boat in-place sensor is arranged outside the sintering furnace, the real position of the material boat in the sintering furnace can be directly measured, the problem of false triggering of non-contact detection caused by environment change in the furnace is avoided, online maintenance and setting can be conducted outside, and the reliability of long-period operation of the material boat in-place sensor is guaranteed.

This disclosure relates to the technical field of transmutation fuel preparation, and more particularly to a method for pressing inert-based dispersed nuclear fuel green blanks, comprising: weighing a predetermined mass of inert-based dispersed nuclear fuel powder; pouring the inert-based dispersed nuclear fuel powder into a pressing mold; using a first punch and a second punch to extend into the pressing mold for bidirectional pressing; and performing a demolding operation on the pressing mold to obtain an inert-based dispersed nuclear fuel green blank. By applying bidirectional synergistic pressure at both ends of the pressing mold, the uniformity of the density distribution of the inert-based dispersed nuclear fuel powder is improved, while expansion defects in the middle of the inert-based dispersed nuclear fuel green blank are avoided, thereby significantly improving the yield and demolding completion of the inert-based dispersed nuclear fuel green blank.

This application relates to a method and apparatus for determining the equivalent thermal conductivity of nuclear fuel. The method includes: obtaining a target simulated nuclear fuel; the target simulated nuclear fuel includes simulated fission bubbles, simulated fuel particles, and a simulated inert matrix; controlling a first surface of the target simulated nuclear fuel to maintain a first temperature, and controlling a second surface of the target simulated nuclear fuel to maintain a second temperature; the first and second surfaces are parallel in the target simulated nuclear fuel; the first temperature is higher than the second temperature; determining the fuel heat flux density flowing from the first surface to the second surface in the target simulated nuclear fuel; the fuel heat flux density includes the particle heat flux density of the simulated fuel particles, the matrix heat flux density of the simulated inert matrix, and the bubble heat flux density of the simulated fission bubbles; and determining the equivalent thermal conductivity of the target nuclear fuel based on the particle heat flux density, the matrix heat flux density, and the bubble heat flux density. This method can accurately determine the equivalent thermal conductivity.

This invention provides a method for evaluating the properties of fuel debris containing a mixture of nuclear fuels with varying burnup levels. [Solution] The evaluation method includes the step of calculating the fissile material ratio indicating the properties of the fuel debris based on the evaluated values ​​of the Cm-244 count rate and the amount of fissile material of the fuel debris, data showing the correlation between the ratio of the Cm-244 count rate and the amount of fissile material and the fissile material ratio, and / or the evaluated values ​​of the Eu-154 count rate and the amount of fissile material of the fuel debris, data showing the correlation between the ratio of the Eu-154 count rate and the amount of fissile material and the fissile material ratio.

The application provides a nuclear fuel transfer channel sealing test interface device, which comprises a nut, a pushing chuck, a sealing chuck and a pipeline interface. The nut is threadedly connected with the pushing chuck, the pushing chuck is axially limited with the sealing chuck, and the sealing chuck is sealingly matched with the pipeline interface through a conical surface. The application reduces the risk of personnel irradiation and tool falling and improves safety through a tool-free quick release mechanism and reliable sealing performance. One person can quickly complete installation and disassembly, saving overhaul time and improving work efficiency. The two structures of the nut ensure reliable sealing between the device and the external pipeline or equipment, avoiding leakage. The device can adapt to sealing requirements under different test conditions, such as vibration and temperature change, and has wide applicability. Through the detachable and replaceable design of the device, the maintenance and replacement of parts are facilitated, and the maintenance cost is reduced.

The present invention provides an operational plan generation device, etc., that generates operational plans that take into account the uncertainty of future conditions regarding nuclear fuel cycle facilities. [Solution] The operation plan generation device 10 includes a constraint acquisition unit 121 that acquires combinations of multiple patterns of constraints as operational constraints for the nuclear fuel cycle facility, an operation plan search unit 122 that searches for an operation plan for the nuclear fuel cycle facility toward the optimization of a predetermined objective function under the constraints of each of the aforementioned combinations, and an output control unit 126 that outputs the search results for the operation plan for each of the aforementioned combinations.

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 present application belongs to the technical field of nuclear fuel element manufacturing, and particularly relates to a machining method and device for a tooth-shaped part of a nuclear fuel element. The machining method comprises a general-purpose machine tool, a fixing tool and a machining tool. The general-purpose machine tool is provided with the fixing tool on one side and the machining tool on the other side. The present application has the advantages that the machining and batch production of the tooth-shaped part of the tube-type fuel element are realized through the machining tool and the machining method, the material utilization is improved according to the structural characteristics of the tooth-shaped part, and technical support is provided for the preparation of the fuel element. The special machining tool is designed and manufactured to solve the problem of tooth-shaped groove machining. The existing equipment is modified to have the capability of small-batch production and reduce the investment in equipment. The machining method of the tooth-shaped part is formulated to improve the material utilization.

A filtering arrangement for use in a bottom nozzle of a fuel assembly in a nuclear reactor includes a top surface, a bottom surface, a plurality of vertical wall portions arranged in a generally squared grid-like pattern which extend between the bottom surface and the top surface and define a plurality of non-circular passages extending between the bottom surface and the top surface through the arrangement, and a plurality of first debris filters which are each positioned between the top surface and the bottom surface to generally span across a respective one of the plurality of passages.

This invention relates to a method and system for treating interface contaminants in a mixing and clarification tank, belonging to the field of nuclear fuel reprocessing. The method involves conveying interface contaminants to the final stage mixing and clarification tank via top-tank operation, separating the organic phase, and then returning the liquid containing interface contaminants from the final stage mixing and clarification tank to the organic phase inlet of the first stage mixing and clarification tank. The interface contaminants are dispersed by the agitation of the pump impeller within the mixing and clarification tank, thereby redissolving radioactive materials in the liquid. This invention utilizes in-situ treatment of interface contaminants and recovery of radioactive elements in a mixing and clarification tank, significantly reducing the accumulation of radioactivity in interface contaminants, mitigating radiation damage from organic solvents, and is simple to operate without requiring additional treatment equipment.

This invention discloses a purification method for producing molybdenum-99 in a reactor using uranyl nitrate solution as nuclear fuel, relating to the field of radioisotope production technology. The method involves first adding an oxidant to the crude molybdenum-99 product solution produced by the solution reactor, oxidizing the crude molybdenum-99 product to MoO4. 2‑ The solution is then evaporated to dryness; a digestion solution is added to the evaporation residue to dissolve the impurities; a dissolving solution is added to the digested solid to dissolve the solid, which is then evaporated to dryness; finally, an alkaline solution is added to the evaporated solid to dissolve it, yielding a molybdenum-99 product solution that meets pharmacopoeia requirements. Compared to traditional methods for purifying molybdenum, this invention does not introduce new impurities, has a low heating temperature, low energy loss, is easy to operate in a hot chamber, and has a high impurity removal rate.

The application provides a kind of nuclear fuel pellet automatic cleaning equipment, belongs to the technical field of pellet cleaning, solve the problem of low efficiency, large labor intensity, long time of operator contact radioactive material in prior art. It includes a protective cover, the inner side of the protective cover is provided with ultrasonic cleaning device, air heater and moving mechanism, moving mechanism is connected with pellet placing frame, moving mechanism moves pellet placing frame to ultrasonic cleaning device or air heater. Set the moving mechanism to move the pellet placing frame to the ultrasonic cleaning device for cleaning or to the air heater for drying treatment, realize automatic cleaning and drying operation, reduce the work intensity, and set the protective cover to isolate the related equipment, avoid the operator to contact the radioactive material for a long time;The cleaning equipment of the application can clean and dry small batches of pellets at the same time, improve the processing efficiency.

The present application relates to a kind of nuclear fuel cladding tube spiral rib rolling equipment, including rotatably arranged drive sleeve, and at least two rollers, for rolling thin-walled cladding tube with spiral rib, the at least two rollers are arranged in the drive sleeve, and relative to the drive sleeve is arranged in planetary roller type, each roller includes the transmission section matched with the drive sleeve and the rolling section connected with the transmission section.Because drive sleeve can drive roller assembly planetary rotation, thin-walled cladding tube with spiral rib can be rolled by roller assembly, without twisting, without fatigue failure caused by twisting, increase service life.At the same time, since the limiting device in roller assembly can limit the position of roller, the spiral rib precision obtained by using the nuclear fuel cladding tube spiral rib rolling equipment is higher, with higher yield.

The application discloses an experimental test and evaluation method for simulating breakage of a nuclear fuel rod and escape characteristics of fission products, which comprises consideration of similarity criteria, and ensures that the cylindrical geometry of the broken fuel rod can simulate the flow characteristics of the flow field near the break along the axial direction of the cylindrical surface; and the flow similarity in the experimental section is realized by Re>10 5 The flow field enters the self-modification area; the critical break diameter is determined based on the blocking flow theory; the specific experimental conditions are determined by single variable control processing of multiple factors; the release rate of fission products per unit time and the escape rate of fission products finally entering the coolant are divided into two experiments of fuel rod constant internal pressure and fuel rod sealing for measurement; and high-confidence uncertainty evaluation is carried out by using A and B two types of evaluation components; and the experimental results are used to fit the fission product escape rate coefficient model. The application solves the problems of poor reliability of experimental extrapolation, blind selection of working conditions and incomplete evaluation system, and provides high-precision benchmark data for nuclear safety analysis programs.

Provided in the present application are a method and apparatus for determining a nuclear fuel loading and unloading mode, and a device and a storage medium. The method for determining a nuclear fuel loading and unloading mode comprises: acquiring a unit number of an adjacent core unit corresponding to a target core unit, the unit number indicating a positional relationship between the adjacent core unit and the target core unit; on the basis of the unit number, acquiring a nuclear fuel storage state of the adjacent core unit; on the basis of the nuclear fuel storage state and the unit number, determining a target core offset mode and a target loading auxiliary tool guiding mode for the target core unit when same performs nuclear fuel loading and unloading; and on the basis of the target core offset mode and the target loading auxiliary tool guiding mode, determining a target loading and unloading mode corresponding to the target core unit. By means of the embodiments of the present application, the efficiency and accuracy of determining a nuclear fuel loading and unloading mode for a nuclear reactor core can be improved.

This disclosure relates to the technical field of transmutation fuel preparation, and more particularly to a method for preparing inert-based dispersed nuclear fuel coated particles, comprising: obtaining spherical nuclear fuel particle powder; pre-spheroidizing the spherical nuclear fuel particle powder to obtain spherical nuclear fuel particle powder; and coating the surface of the spherical nuclear fuel particles with inert matrix powder using a rolling coating method to obtain inert-based dispersed nuclear fuel coated particles. By controlling the distribution state of spherical nuclear fuel particles in the inert matrix powder, the radiation resistance of inert-based dispersed nuclear fuel coated particles is improved. Furthermore, the dispersed coated nuclear fuel pellets prepared in this way exhibit a more uniform nuclear fuel temperature field distribution, reducing thermal stress caused by temperature gradients, lowering the risk of cracking, improving the integrity and reliability of the dispersed coated nuclear fuel pellets, and reducing local overheating problems caused by the aggregation of spherical nuclear fuel particles, thereby lowering the operating temperature of the dispersed coated nuclear fuel pellets and improving reliability.

Underground nuclear installation (10), comprising: - a vertical shaft (12) having, at a lower end, a bottom (12a) and, at an upper end, an opening (12b), - at least one reactor building (26) housed in the shaft, - at least one protective slab (20) against external aggressions which seals the opening (12b) of the shaft by extending in particular above said at least one reactor building, - at least one nuclear reactor containment (30) enclosed within said at least one reactor building (26) and supported by at least one support slab (32) resting on the bottom of the shaft by means of a plurality of seismic isolation devices (SIDs), - and / or at least one nuclear fuel storage pool (NFSP) housed in the shaft and supported by at least one support slab (DS) resting on the bottom of the shaft by means of a plurality of seismic isolation devices (SIDs). Figure for the summary: Fig. 3.

Nuclear fuel rod cladding and method for manufacturing such cladding. The cladding comprises a tube (14) extending along a longitudinal axis and a tubular inner lining (18) received inside the tube (14), the tube (14) comprising at least one reinforced layer (16) made of a composite material comprising a ceramic matrix reinforced with ceramic reinforcing fibers, the thickness of the tube (14) being between 280 µm and 600 µm. Figure for the abstract: Figure 1

This utility model relates to the field of nuclear fuel element manufacturing technology and discloses a dual-station fluidized tube and gas distributor extraction device, including a fixed frame, a horizontal drive mechanism, and a lifting assembly. The fixed frame is provided with a horizontal movement space and a dual-station rotation assembly. The horizontal drive mechanism drives the lifting assembly to move horizontally within the horizontal movement space. The dual-station rotation assembly is located below the horizontal movement space. Two temporary storage fixtures of the dual-station rotation assembly are used to accommodate the extracted fluidized tube or gas distributor. The lifting assembly includes a support, a primary lifting drive mechanism, a primary lifting slide rail, a lifting frame, a secondary lifting drive mechanism, a secondary lifting slide rail, and a multi-stage telescopic arm. The support slides horizontally with the fixed frame. The dual-station fluidized tube and gas distributor extraction device provided by this utility model solves a series of problems existing in the manual hoisting of graphite parts (such as fluidized tubes and gas distributors) in high-temperature environments.

This article describes embodiments of a nuclear fuel element for use in various types of nuclear reactors. One embodiment of the nuclear fuel element comprises a plurality of solid nuclear fuel particles, such as tristructural isotropic fuel particles (TRISOs), intermixed in a non-solid matrix that is substantially stagnant relative to the plurality of solid nuclear fuel particles. The non-solid matrix may comprise a liquid metal, a liquid metal alloy, and a liquid salt. Various embodiments of the non-solid matrix include tin, lead, sodium, aluminum, bismuth, and alloys thereof. A method for manufacturing a nuclear fuel and embodiments of a nuclear fuel hub comprising the nuclear fuel element are also described.

The present application belongs to the technical field of high temperature gas cooled reactor nuclear fuel element industrial production gas phase deposition coating furnace automation, and particularly relates to a device for coating furnace loading and discharging and rapid cleaning. A top cover translation mechanism is connected with a top cover grabbing and lifting mechanism. A top cover bottom surface cleaning mechanism and a special top cover for furnace cleaning are placed at a platform fixed position. An AGV trolley is automatically parked at a bottom empty area of the device. A feeding and sampling discharging mechanism is placed above the coating furnace. Graphite pieces grabbed from the coating furnace are placed in a graphite piece cleaning cabin. A brush cleaning mechanism is located around the graphite piece cleaning cabin. A fluidized pipe cleaning cabin stores hoisted fluidized pipes. The fluidized pipes are hoisted and taken out from the coating furnace. The present application solves the problem of low automation degree of coating furnace system loading and discharging and related component cleaning, and improves production efficiency and long-term use stability.

A nuclear fuel rod comprises nuclear fuel contained in a cladding, the cladding comprising a tube and two plugs, the tube extending along a central axis and having two ends, each plug being attached to a corresponding end of the tube by sealing the end of the tube. The tube is covered by a tube coating extending over the entire length of the tube from one end of the tube to the other.

The spacer grid elements (18) define cells (16) for receiving nuclear fuel rods (4). The spacer grid elements (18) are configured to be arranged side-by-side with applying two side walls (22) of two adjacent spacer grid elements (18) one against the other. One of the two side walls (22) of at least one pair of side walls (22) applied against each other is provided with a lower flap (34) protruding from the lower edge of said side wall (22) such as to at least partially cover the lower edge (22A) of the other side wall and / or one of the two side walls (22) of said at least one pair of side walls (22) applied against each other is provided with an upper flap (34) protruding from the upper edge of said side wall (22) such as to at least partially cover the upper edge (22B) of the other side wall.

Example systems include modular reactor pods that can be separately shipped, delivered, and assembled at a commercial electricity generating site. Systems may include central pods that can be loaded with and house a nuclear fuel core carrying a coolant from a primary coolant flow path through the core. One or more pump pods and / or heat exchanger pods can be attached to the reactor pod post-fabrication and even post-delivery at the site. The pump and heat exchanger pods carry the continuous coolant flow path and recirculate the same into the central pod. The pods can be connected in any manner to secure the flow path in a continuous and impermeable fashion, such as by welding or hermetically sealing the pods at each point where the flow path passes between the pods.

This invention relates to the field of spherical nuclear fuel element molding technology, specifically to an isostatic pressing molding die and a method for preparing spherical fuel element blanks. The isostatic pressing molding die includes an isostatic pressing core ball mold for pressing the core ball and an isostatic pressing molding die for pressing the spherical fuel element blank. It consists of at least a die body and an inverted conical top cover for closing the opening of the die body. After mold closing, both the internal cavity and the external shape are spherical. The die material is one of nitrile rubber, silicone rubber, EPDM rubber, natural rubber, and polyurethane. When preparing spherical fuel element blanks using this die, nuclear fuel and matrix graphite powder are first filled into the die body of the core ball mold and stirred evenly. After mold closing, it is vacuum-sealed and isostatically pressed to obtain the core ball. Then, the core ball and matrix graphite powder in the fuel element blank mold are loaded, vacuum-sealed, and isostatically pressed to obtain the spherical fuel element blank. This invention provides convenient material loading, easy demolding, and reusability of the die, and also helps improve the isotropy and molding quality of the spherical fuel element blank.