292results about "Reactors manufacture" patented technology

A system is described that includes a sputter target and a magnetic element array including multiple sets of magnets arranged to have a Hall-Effect region that extends along a length of the sputter target. The elongated sputtering electrode material tube is interposed between the magnetic array and an object to be deposited with a sputtered material from the sputter target. During a direct current high-power impulse magnetron sputtering operation, the system performs a depositing on a surface of the object by generating and controlling an ion and neutral particle flux by: providing a vacuum apparatus containing a sputter target holder electrode; first generating a high-power pulsed plasma magnetron discharge with a high-current negative direct current (DC) pulse to the sputter a target holder electrode; and second generating a configurable positive voltage kick pulse to the sputter target holder electrode after terminating the negative DC pulse.

The invention relates to a nuclear fuel cladding produced with a substrate (14) which is made of pure zirconium or of a zirconium based alloy and a multilayer protective coating (16) which covers a surface (14B) of the substrate (14), the protective coating (16) comprising a main layer (18) made of pure chromium and one or more additional layers (20), each additional layer (20) being made of pure chromium or from a material made of chromium and, additionally, oxygen and / or nitrogen, with the possible presence of unavoidable impurities.

The invention provides a high-strength winding thin-wall SiC composite cladding tube and a preparation method thereof. A preparation method of a high-strength winding thin-wall SiC composite cladding tube comprises the steps that silicon carbide fibers are wound and laid around a core mold, the winding pre-tightening force is smaller than or equal to 10 N. The winding mode comprises the first mode that one layer of annular winding is conducted firstly, then one layer of spiral winding is conducted, and the number of fiber intersection points in the whole annular direction at a certain position of the outer surface of the core mold is 1. One-layer annular winding is carried out firstly, then two-layer spiral winding is carried out, the number of fiber intersection points in the whole annular direction at a certain position of the outer surface of the core mold is 3, and a prefabricated body is obtained; carrying out a densification deposition process on the preform, wherein the densification deposition process comprises PyC pyrolytic carbon interface deposition, CVI chemical vapor infiltration and CVD chemical vapor deposition; and precise inner circle and outer circle machining is conducted, and the SiC composite cladding pipe is obtained. According to the preparation method disclosed by the invention, through a specific dry winding mode and a densification deposition process, the SiC composite material tube blank is higher in density and better in mechanical property.

The invention belongs to the technical field of nuclear fuel element surface protection, and particularly relates to a multi-layer composite (Cr, Al) Nx / Cr protective coating for a nuclear reactor zirconium alloy cladding and a preparation method of the multi-layer composite (Cr, Al) Nx / Cr protective coating. The coating adopts a multi-layer structure design consisting of a buffer layer, a middle layer and an outermost layer in sequence from inside to outside, wherein the buffer layer is a Cr coating; the middle layer is a nitrogen-saturated (Cr, Al) Nx coating, x is larger than or equal to 1, the middle layer is of a columnar crystal structure, and the hardness of the middle layer is 5-10 GPa; the outermost layer is a non-stoichiometric ratio (Cr, Al) Nx coating, x is larger than or equal to 0.6 and smaller than or equal to 0.9, a nanocrystalline structure is shown, and the hardness is 12-25 GPa. Component regulation, hardness gradient and a microstructure are subjected to collaborative design, so that the coating has excellent wear resistance, high oxidation resistance and structural integrity at the same time under a harsh nuclear working condition, the safety margin of the zirconium alloy cladding under normal service and accident working conditions is greatly improved, and the service life of the zirconium alloy cladding under normal service and accident working conditions is greatly prolonged.

The invention belongs to the technical field of nuclear fuel preparation, aims to solve the problems of non-uniform particle distribution and high breakage rate in traditional coated particle fuel preparation, and discloses a coated particle dispersion fuel pellet and a preparation method thereof.The method comprises the steps that firstly, silicon carbide slurry is prepared, a silicon carbide base band is prepared through tape casting equipment, and then the silicon carbide base band is prepared; after tape casting, the base band enters a drying area to be partially dried, TRISO particles are arranged on the surface of the base band at set intervals, the silicon carbide base band is freely curled and formed from one end, degreasing treatment and sintering densification are conducted, and the core block is prepared through the method. Through high-precision tape casting and three-dimensional curling technologies, uniform distribution of TRISO particles in CDF is achieved, and the contact and breakage rate of fuel in the preparation process is reduced.

Additive manufacturing compositions include low-absorbing particles or non-absorbing particles that have an absorbance for wavelengths of 300 nm to 700 nm that is equal to or greater than 0 Au and is less 1.0 Au, such as 0.001 Au ≤ absorbance ≤ 0.7 Au. Slurries including such particles and an uranium-containing particle and that are used in additive manufacturing processes have an increased penetration depth for curative radiation. Removal of low-absorbing particles or non-absorbing particles during post-processing of as-manufactured products results in pores that create porosity in the as-manufactured product that provide a volume accommodating fission gases and / or can enhance wicking of certain heat pipe coolant liquids. Low-absorbing particles or non-absorbing particles can be functionalized for improved properties, for example, with fissionable material for improved ceramic yields, with burnable poisons or stabilizers for increased homogeneity, with stabilizers for localized delivery of the stabilizer, or with combinations thereof.

The embodiment of the invention relates to the field of processes specially used for manufacturing a reactor or parts thereof, in particular to an assembling and charging testing method of a reactor using bulk nuclear fuel and the reactor comprising the bulk nuclear fuel. According to the method, loading test is carried out on the reactor by using the test facility after assembly, so that the backup reactivity of the reactor core can be determined, safe assembly and safe criticality of the reactor are realized, and the safety of experimenters is ensured; by gradually adding the partitioned side reflecting layers outside the reactor core formed by the bulk nuclear fuel, the reactor gradually reaches the critical value, the operation risk is reduced, and meanwhile, the critical point can be accurately obtained; after the critical loading of the reactor core is determined, the partitioned side reflecting layers are replaced by the complete side reflecting layers with the same value, so that the influence of gaps existing between the partitioned side reflecting layers can be avoided, and the reaction efficiency of nuclear fuel is improved. The reactor assembled according to the method has high neutron economy and low critical risk.

The present invention relates to a system (1) for extracting UF6 from a UF6 container placed in an autoclave (5), comprising a pump (24) having an inlet port (26) being connected to an upstream supply circuit (10, 20), the upstream supply circuit (10, 20) transporting UF6 from the autoclave to the pump (24); wherein the system further comprises a temperature- controlled subsystem (3) providing a heat supply to the pump (24) and at least a downstream portion of the upstream supply circuit (10, 20), the temperature-controlled subsystem (3) heat supply being adapted to maintain a temperature within the upstream supply circuit and the pump (24) during operation such that said temperature is above the crystallization temperature of UF6.

Described herein is a process for recovering uranium tetrafluoride (UF4) from hexafluoride uranium (UF6), the process comprising dissolving UF6 directly in an ionic liquid and recovering UF4, which can be processed to obtain UO2(s) or metallic uranium.

A nuclear reactor is designed to couple the load path of the control elements with the reactor core, thus reducing the opportunity for differential movement between the control elements and the reactor core. A cartridge core barrel can be fabricated in a manufacturing facility to include the reactor core, control element supports, and control element drive system. The cartridge core barrel can be mounted to a reactor vessel head. Thus, any movement, such as through seismic forces, transmits an equal direction and magnitude to the control elements and the reactor core. This arrangement reduces the opportunity for differential movement between the control elements and the reactor core.

In many embodiments, a plurality of neutron moderators may be arranged to define a plurality of flow channels within a reactor vessel, wherein each neutron moderator of the plurality of neutron moderators includes at least one surface face, and each neutron moderator is not machined. In some embodiments, the flow channel may be defined by the at least one surface face of each neutron moderator of the plurality of neutron moderators. In at least one embodiment, the plurality of neutron moderators may include at least three neutron moderators. In several embodiments, the plurality of neutron moderators may include a first pair of neutron moderators and a second pair of neutron moderators. In one or more embodiments, the first pair of neutron moderators and the second pair of neutron moderators may be arranged to form a lattice configuration in a reactor vessel.

The invention belongs to the nuclear industry and can be used for the production of fuel pellets from uranium-molybdenum metal powder enriched with uranium-235 to 7%, which can be used as fuel elements for nuclear reactors. The sintering of the pellets is carried out in an inert argon atmosphere at a temperature in the range of 1100°C to 1155°C, as the initial powder, a particle size of 160 μm is used, with a molybdenum content of 9.0 to 10.5 wt.%. The powder is preheated at a temperature of 500°C for 10-20 hours (in an argon medium), and then cold-pressed into pellets in a mold at a pressure of up to 950 MPa. According to another method, when preparing uranium-molybdenum pellets using a binder (plasticizer), the pellets are heated in argon from 300°C to 450°C for a duration of 2-4 hours before sintering, in order to remove the binder. The invention allows to increase the uranium content in the fuel, to reduce the heat accumulated in the core of the nuclear reactor, and to reduce the energy release in the event of a violation of the normal operating conditions of the nuclear reactor, which will improve its safety and emergency stability.

The invention relates to the technical field of nuclear power testing, and discloses a penetration piece for nuclear power equipment testing and a preparation and use method thereof.The penetration piece comprises a connector piece, a sleeve, an abutting piece and an elastic sealing assembly, one end of the connector piece is provided with a first connecting part, and the other end of the connector piece is provided with a second connecting part; a heat dissipation structure is arranged between the first connecting part and the second connecting part of the joint piece, and the first connecting part is detachably connected with the pressure-bearing wall surface of the test container; the open end of the sleeve is movably and detachably connected with the second connecting part; the abutting piece is arranged in the sleeve, and an elastic sealing assembly is arranged between the abutting piece and the sealing end of the sleeve. The connector piece, the abutting piece, the elastic sealing assembly and the sleeve are provided with through penetrating holes. The penetrating piece can adjust the position of the penetrating part; heat dissipation is enhanced through the heat dissipation structure; and the position of the elastic sealing assembly for sealing the penetrating part is far away from the test container, so that the sealing effect at high temperature and high pressure is realized.

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 fuel preparation, and particularly relates to a powder discharging structure used in the annular pellet green pressing process, which comprises an upper punch, a punch sleeve, an upper punch rod and a center rod. The base of the upper punch is used for being installed on the top of an upper punch rod. The punch sleeve is used for penetrating through the upper portion of the upper punch and is in threaded connection with the upper punch rod. A center hole and a powder discharging hole are formed in the upper punch. The powder discharging hole is formed in the side edge of the center hole. One end of the center rod is used for being installed at a center hole of an upper punch, and the other end of the center rod is used for being installed on rotary forming press equipment. The powder discharging hole is formed in the side edge of the center hole of the upper punch, so that the technical problem that the upper punch is prone to breakage due to the fact that powder discharging is not timely in the annular pellet green pressing process is solved.

To provide nuclear reactor shielding facilities which are easier to construct while maintaining high radiation shielding performance.SOLUTION: A nuclear reactor shielding facility for shielding the surroundings of a nuclear reactor installed on an installation surface is provided, the facility comprising a base structure provided along an outer circumference of an area other than the installation surface to surround the entire surroundings of the nuclear reactor other than the installation surface, and a shielding structure provided on an entire surface of the base structure and provided with water filled therein.SELECTED DRAWING: Figure 2

An in-situ wick rolling and forming assembly configured to roll and form a heat pipe wick from a wick mesh. The in-situ wick rolling and forming assembly includes a first forming shell, a grooved mandrel, and an expandable member. The first forming shell is configured to form the wick in-situ after rolling the wick mesh. The first forming shell includes a first recess and a first parting surface. A first central axis of the first recess is located below the first parting surface. The grooved mandrel is removably positioned within the first recess.

The application discloses a preparation method of FCM fuel pellets by gel injection molding, which comprises the following steps: preparing SiC-based slurry, injecting the slurry into a mold, adding TRISO fuel particles into the SiC-based slurry, and performing water bath solidification forming to obtain a green pellet, drying and degassing the green pellet to obtain a semi-product pellet, sintering the semi-product pellet to obtain the FCM fuel pellet. The FCM fuel pellet prepared by the gel injection molding technology has a good surface appearance, a compact structure and few surface defects, the volume proportion of the TRISO particles is effectively improved, and the neutron economy of the FCM fuel is improved. The prepared FCM fuel has the characteristics of high thermal conductivity, corrosion resistance, closed fissile product and gas, and the safety of a nuclear reactor is further improved. The preparation method saves the time cost in the production process, improves the production efficiency and is good in economy.

Nuclear fuel cladding for fast reactors, assemblies thereof, and methods of manufacture thereof are provided. The nuclear fuel cladding comprises a substrate, a first layer, and a second layer. The substrate comprises a tubular shape. The first layer is deposited over an external surface of the substrate. The first layer comprises a corrosion resistant composition. The second layer is disposed over the first layer. The second layer comprises silicon carbide fibers infiltrated with silicon carbide. The second layer is configured to inhibit outward creep of the substrate. A gap is defined intermediate the first layer and the second layer.

The invention discloses a fuel assembly guide pipe plug pressing device, and belongs to the technical field of fuel assembly manufacturing. The device comprises a machining platform, bearing plates are symmetrically and fixedly connected to the top of the machining platform, a clamping moving assembly is jointly and fixedly installed on the side walls of the bearing plates, a moving limiting assembly is fixedly installed on the top of the machining platform, a controller is fixedly installed on the side wall of the machining platform, and an alarm lamp is fixedly installed on the top of the controller; according to the invention, by arranging the first electrode plate, the second electrode plate, the alarm lamp and other structures, the outer wall of the end plug, the inner wall of the guide pipe and the side wall of the pipe orifice of the guide pipe can be detected before the end plug is pressed into the guide pipe; if the outer wall of the end plug, the inner wall of the guide pipe and the side wall of the pipe opening of the guide pipe are sunken or protruded, the sliding plate can make contact with the first electrode plate or the second electrode plate, and then the alarm lamp is normally turned on to remind a worker that the end plug or the guide pipe is deformed.

A preparation method for a gradient near-equiaxed crystal Cr coating on the surface of a zirconium alloy cladding is described. According to the present invention, a high-power impulse magnetron sputtering technology is adopted, and by self-modification of HiPIMS equipment, argon gas is introduced into a zirconium alloy cladding tube, the flow rate of the argon gas in the tube is controlled to regulate and control the tube wall temperature, parameters such as bias voltage, target-substrate distance, sputtering pressure and the like are comprehensively controlled to obtain a pure Cr near-equiaxed crystal coating on the surface of the zirconium alloy with three-layer gradient structure grains. The coating has good toughness and can improve the high-temperature oxidation resistance of the zirconium alloy cladding, significantly enhancing the ability of the cladding to resist serious accidents of the reactor.

The invention relates to the field of nuclear fuel, in particular to a glass packaging method for a silicon carbide cladding tube. The method comprises the following steps that firstly, welding flux is prepared, and the welding flux comprises 20 wt% of MgO-20 wt% of Al2O3 and 60 wt% of SiO2; secondly, the silicon carbide cladding and the silicon carbide end plug are assembled; thirdly, after polyvinyl alcohol and welding flux are mixed, the welding seam area is filled with the welding flux; 4, the silicon carbide cladding tube added with the welding flux is heated in an inert gas environment, heating is divided into two stages, in the first stage, the silicon carbide cladding tube is heated to 500 DEG C and then subjected to heat preservation for 25-60 minutes, and in the second stage, the silicon carbide cladding tube is slowly heated to 1300-1350 DEG C and subjected to heat preservation for 10-30 minutes; and slowly cooling to room temperature after the second-stage heat preservation is finished. Non-pressure connection of the silicon carbide cladding pipe and the end plug is achieved, and it is ensured that the connected connector has the advantages of being high in strength, resistant to radiation and excellent in sealing performance.

The invention relates to a process for preparing a powder comprising one or more oxides selected from uranium oxide UO2, plutonium oxide PuO2 and minor actinide oxides, the minor actinides being selected from americium, neptunium and curium, comprising the steps of: a) cryogenic granulation of an aqueous solution comprising cations selected from uranium-based cations, plutonium-based cations and minor actinide-based cations; b) freeze-drying of the granules obtained in a); etc.; calcination of the granules from b). Applications: manufacture of nuclear fuels or blankets loaded with minor actinide(s).

The application belongs to the technical field of nuclear energy functional materials and advanced ceramic preparation, and discloses a preparation method of high-uniformity europium hafnate nano-powder based on a complexation-gel method. 3+ With Hf 4+ Atomic-level uniform mixing, solves the microsegregation problem existing in the traditional preparation method, reduces the synthesis temperature, and the product is free of impurities and hard agglomeration, has excellent sintering activity, and is strong in process controllability and easy to be enlarged in engineering, is suitable for the preparation of nuclear reactor neutron absorption control rod materials, and has good industrial application prospect.

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 application discloses a method for optimizing process parameters of metal type nuclear fuel preparation process, collecting and arranging metal type nuclear fuel preparation process parameters and performance parameters, post-preparation performance parameters and microstructure metallographic pictures; establishing a metal type nuclear fuel solidification phase field model according to a solidification thermodynamic path under different process parameters; solving the metal type nuclear fuel solidification phase field model by using a Fourier spectrum method to obtain a phase field variable numerical solution; post-processing and visualizing the phase field variable numerical solution to generate a microstructure distribution map of the metal type nuclear fuel after solidification, and comparing and verifying the phase field model with the metal type nuclear fuel microstructure metallographic picture; calculating the post-solidification performance parameters of the metal fuel based on the microstructure distribution of the metal type nuclear fuel after solidification; taking the preparation process parameters as input and the performance parameters as output, constructing a nonlinear mapping proxy model between the metal type nuclear fuel preparation process parameters and the performance parameters; and solving the optimal preparation process parameters by using the nonlinear mapping proxy model given the target performance parameters of the metal type nuclear fuel.

The present application belongs to the field of forging, and particularly relates to a manufacturing method of a high-purity and high-homogenization nuclear power pressure vessel. First, the continuous casting slab is screened through the chemical composition segregation amount, and the high-homogenization continuous casting slab is screened as a building block; then the length, width or diameter of the homogenization building block is processed in equal size, and after cleaning treatment, multiple building blocks are stacked, and the stacked multiple homogenization building blocks are vacuum packaged to form a building blank, and after packaging, the building blank is removed from the vacuum chamber and placed into a heating furnace to be heated to a forging temperature for building forming forging; finally, the high-purity and high-homogenization nuclear power pressure vessel is manufactured through forging or ring rolling. The cylinder forging produced by the method not only has good composition homogeneity, but also has good uniformity of mechanical properties, greatly improving the comprehensive performance of the cylinder forging, and providing a new method for high-purity and high-homogenization manufacturing of nuclear power pressure vessel forgings.

The invention relates to a nuclear fuel pellet (6) embedded with a thermally conductive insert (7) in the form of branching arms (7.1 to 7.6) distributed from a hollowed-out inner cylinder (61) towards the outside of the pellet. The invention essentially consists of a nuclear fuel pellet (6) embedded with, within a straight cylindrical ring (60) of fissile material, a thermal conductor (7), in particular a metal conductor, in the form of main branching arms (7.1 to 7.6) that extend from the inside of the ring (60) to the outside and are advantageously distributed homogeneously within the ring. The insert made up of its macrostructure arms and branches makes it possible to reduce the maximum temperature of the fuel by several hundreds of degrees Celsius according to its dimensions, its constituent material and the distribution of its arms in the straight cylindrical fuel ring (60).

The manufacturing method is intended for the manufacture of a nuclear fuel rod cladding (4) comprising a substrate (14) covered with a protective coating (16). The manufacturing method comprises providing the substrate (14) and applying the protective coating (16) to the substrate (14) by physical vapour deposition by sputtering, simultaneously employing two or more mutually different techniques of physical vapour deposition by sputtering.

An installation for the conversion of uranium hexafluoride (UF6) to uranium dioxide (UO2) comprises a hydrolysis reactor (4) for the conversion of UF6 into uranium oxyfluoride powder (UO2F2), a pyrohydrolysis furnace (6) for converting the UO2F2 powder supplied by the reactor (4) into UO2 powder, a supply device (8) comprising reagent injection ducts (10) for the injection of UF6, water vapor or H2, and a control system (16) designed to control the supply device (8) so as to supply at least one of the reagent injection ducts (10) with a neutral gas during a shut-down or start-up phase of the conversion installation.