A filter for separating particles from a cooling liquid in a nuclear power plant includes a filter part arranged in a filter frame cooperating with a mounting part of a component of the nuclear power plant for mounting of the filter in the component. The filter frame includes a protruding part and/or a recess extending along an extension direction substantially perpendicular to a plane extending along a surface portion of an outer surface of the filter frame. The protruding part and/or the recess are arranged along the entire circumference of the filter frame along an outer edge of the filter frame. The protruding part and/or the recess are arranged to create an obstacle for the particles flowing between the filter frame and the mounting part. A filter arrangement and a fuel assembly are also described.
A nuclear fuel rod cladding tube is described. The nuclear fuel cladding tube has an oxidation resistant coating of Chromium-Niobium Nitride (Cr—Nb—N). A method for manufacturing a nuclear fuel rod cladding tube is also described.
A filter (1, 1') for separating debris from a cooling liquid in a nuclear plant is described. The filter (1) comprises at least one passage (3) with an inner surface (5), an inlet end (2) and an outlet end (4). The at least one passage (3) is arranged to permit through-flow of the cooling liquid in a main flow direction (MFD) from the inlet end (2) to the outlet end (4) for a cooling purpose in the nuclear plant. The inner surface (5) of the at least one passage (3) comprises at least one surface portion (7, 7') facing a sub flow direction (SFD) of the cooling liquid and comprising at least one surface irregularity (9, 9') arranged to catch the debris flowing in the cooling liquid in the sub flow direction (SFD) during lifting or transportation of the filter (1, 1') after the filter (1, 1') has been used for separating debris from the cooling liquid in the nuclear plant wherein the sub flow direction (SFD) is the opposite direction to the main flow direction (MFD). A fuel assembly (11, 11') for a nuclear plant, comprising a filter (1, 1') is also described.
A filter (1, 1', 1'', 1''') for separating particles from a cooling liquid in a nuclear power plant is described. The filter (1, 1', 1'', 1''') comprises a filter part (2) arranged in a filter frame (3, 3', 3'', 3''') configured to cooperate with a mounting part (5, 5', 5'', 5''') of a component (7) of the nuclear power plant for mounting of the filter (1, 1', 1'', 1''') in the component (7).The filter frame (3, 3', 3'', 3''') comprises at least one protruding part (9, 9', 9'') and/or at least one recess (11) extending along an extension direction (e, e') substantially perpendicular to a plane (p) extending along a surface portion (13) of an outer surface of the filter frame (3, 3', 3'', 3''').The at least one protruding part (9, 9', 9'') and/or at least one recess (11) are arranged along the entire circumference of the filter frame (3, 3', 3'', 3''') along an outer edge (15) of the filter frame (3, 3', 3'', 3'''). The at least one protruding part (9, 9', 9'') and/or at least one recess (11) are arranged to create an obstacle for the particles flowing between the filter frame (3, 3', 3'', 3''') and the mounting part (5, 5', 5'', 5'''). A filter arrangement and a fuel assembly are also described.
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
G21C 19/307 - Arrangements for introducing fluent material into the reactor coreArrangements for removing fluent material from the reactor core with continuous purification of circulating fluent material, e.g. by extraction of fission products specially adapted for liquids
5.
A cladding tube for a fuel rod for a nuclear reactor, a fuel rod, and a fuel assembly
A cladding tube, a fuel rod and a fuel assembly are disclosed. The cladding tube comprises a tubular base component having an outer surface and an inner surface defining an inner space of the cladding tube housing a pile of fuel pellets. The tubular base component is made of a Zr-based alloy. A coating is applied onto the outer surface for protecting the tubular base component from mechanical wear, oxidation and hydriding. The Zr-based alloy has the following composition: Zr=balance, Al=0-2 wt %, Ti=0-20 wt %, Sn=0-6 wt %, Fe=0-0.4 wt %, Nb=0-0.4 wt %, O=200-1800 wtppm, C=0-200 wtppm, Si=0-200 wtppm, and S=0-200 wtppm. The total amount of Al+Ti+Sn>2.5 wt % and ≤28 wt %.
A nuclear fuel rod cladding tube (1, 1') is described. The nuclear fuel cladding tube has an oxidation resistant coating of Chromium-Niobium Nitride (Cr-Nb-N). A method for manufacturing a nuclear fuel rod cladding tube (1, 1') is also described.
A computer-implemented simulation method of predicting local concentrations of constituents in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) potentially resulting in crud deposits on said fuel rods. The method is based on a sub-channel approach of predicting local mass fluxes of vapor and liquid in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) for given steady-state or transient boundary conditions. The sub-channel approach is based on the solution of mass, momentum and energy conservation equations for the vapor phase and the liquid phase, the liquid phase is represented by more than one field variable, and is specifically represented by three fields, with the vapor phase as a fourth field, consisting of droplets, a liquid base film, and disturbance waves. The method comprises:
A computer-implemented simulation method of predicting local concentrations of constituents in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) potentially resulting in crud deposits on said fuel rods. The method is based on a sub-channel approach of predicting local mass fluxes of vapor and liquid in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) for given steady-state or transient boundary conditions. The sub-channel approach is based on the solution of mass, momentum and energy conservation equations for the vapor phase and the liquid phase, the liquid phase is represented by more than one field variable, and is specifically represented by three fields, with the vapor phase as a fourth field, consisting of droplets, a liquid base film, and disturbance waves. The method comprises:
simulating steady-state or transient boundary conditions, such as inlet coolant water flow into said sub-channels, the coolant water flow may have a predetermined flow velocity variation,
A computer-implemented simulation method of predicting local concentrations of constituents in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) potentially resulting in crud deposits on said fuel rods. The method is based on a sub-channel approach of predicting local mass fluxes of vapor and liquid in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) for given steady-state or transient boundary conditions. The sub-channel approach is based on the solution of mass, momentum and energy conservation equations for the vapor phase and the liquid phase, the liquid phase is represented by more than one field variable, and is specifically represented by three fields, with the vapor phase as a fourth field, consisting of droplets, a liquid base film, and disturbance waves. The method comprises:
simulating steady-state or transient boundary conditions, such as inlet coolant water flow into said sub-channels, the coolant water flow may have a predetermined flow velocity variation,
analyzing predefined parameters of said disturbance waves and base film, including wave velocity, wave frequency and base film thickness, and
A computer-implemented simulation method of predicting local concentrations of constituents in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) potentially resulting in crud deposits on said fuel rods. The method is based on a sub-channel approach of predicting local mass fluxes of vapor and liquid in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) for given steady-state or transient boundary conditions. The sub-channel approach is based on the solution of mass, momentum and energy conservation equations for the vapor phase and the liquid phase, the liquid phase is represented by more than one field variable, and is specifically represented by three fields, with the vapor phase as a fourth field, consisting of droplets, a liquid base film, and disturbance waves. The method comprises:
simulating steady-state or transient boundary conditions, such as inlet coolant water flow into said sub-channels, the coolant water flow may have a predetermined flow velocity variation,
analyzing predefined parameters of said disturbance waves and base film, including wave velocity, wave frequency and base film thickness, and
analyzing liquid base film thickness between consecutive passing disturbance waves, to calculate local instantaneous impurity concentrations based on said simulated boundary conditions, the calculation is made for each fuel rod of the fuel assembly, wherein, for each fuel rod, the method further comprises comparing said calculated local instantaneous impurity concentration to a crud compound precipitation limit, and during the time said concentration is higher than said precipitation limit, crud is considered to have occurred. In a related simulation method also base film dryout, clad temperature increase, and drop entrainment from waves, may be determined.
G21C 17/022 - Devices or arrangements for monitoring coolant or moderator for monitoring liquid coolants or moderators
G06F 30/28 - Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
A tube grid cell (2) for a fuel bundle (8) of a nuclear reactor. The tube grid cell (2) having the length (L), comprises a cell housing (10) which has, along the longitudinal axis A, a lower section (16), an upper section (18) and a middle section (20). The middle section (20) is provided with two pairs of support members (22) and a resilient member (24) configured to generate a resilient force in an inward radial direction, the resilient member is arranged at essentially equal distance from the support members (22), and positioned approximately (120) degrees apart from the support members seen along axis A. The upper section (18) and the lower section (16) have respectively a length L1 and L2 along axis A that is larger than 0.1 L and smaller than 0.3 L, and is provided with a solid housing wall, having an even thickness and no openings, indentations or protrusions.
A filter for separating particles from a cooling liquid in a nuclear plant is presented. The filter includes at least one passage with an inner surface, an inlet end and an outlet end, wherein the at least one passage is arranged to permit through-flow of the cooling liquid in a main flow direction (MFD) from the inlet end to the outlet end. The inner surface of the at least one passage includes at least one surface section having a structured surface forming a plurality of surface portions facing the main flow direction (MFD) of the cooling liquid and being arranged to catch the particles. Also, a fuel assembly for a nuclear plant, including a filter is presented.
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
B01D 29/00 - Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups Filtering elements therefor
10.
A CLADDING TUBE FOR A FUEL ROD FOR A NUCLEAR REACTOR, A FUEL ROD, AND A FUEL ASSEMBLY
A cladding tube (11), a fuel rod and a fuel assembly are disclosed. The cladding tube comprises a tubular base component (20) having an outer surface (21) and an inner surface (22) defining 5 an inner space (14) of the cladding tube housing a pile of fuel pellets (10). The tubular base component is made of a Zr-based alloy. A coating (23) is applied onto the outer surface for protecting the tubular base component from mechanical wear, oxidation and hydriding. The Zr-based alloy has the following 10 composition: Zr = balance, Al = 0-2 wt%, Ti = 0-20 wt%, Sn = 0-6 wt%, Fe = 0-0.4 wt%, Nb = 0-0.4 wt%, O = 200-1800 wtppm, C = 0-200 wtppm, Si = 0-200 wtppm, and S = 0-200 wtppm. The total amount of Al+Ti+Sn > 2.5 wt% and ≤ 28 wt%.
C23C 14/16 - Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon
C23C 28/00 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and
C23C 30/00 - Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
11.
COMPUTER-BASED SIMULATION METHODS FOR BOILING WATER REACTORS (BWR)
A computer-implemented simulation method of predicting local concentrations of constituents in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) potentially resulting in crud deposits on said fuel rods. The method is based on a sub-channel approach of predicting local mass fluxes of vapour and liquid in coolant water anywhere along fuel rods within any fuel assembly mechanical design of a Boiling Water Reactor (BWR) for given steady- state or transient boundary conditions. The sub-channel approach is based on the solution of mass, momentum and energy conservation equations for the vapour phase and the liquid phase, the liquid phase is represented by more than one field variable, and is specifically represented by three fields, with the vapour phase as a fourth field, consisting of droplets, a liquid base film, and disturbance waves. The method comprises: - simulating steady-state or transient boundary conditions, such as inlet coolant water flow into said sub-channels, the coolant water flow may have a predetermined flow velocity variation, - analysing predefined parameters of said disturbance waves and base film, including wave velocity, wave frequency and base film thickness, and - analysing liquid base film thickness between consecutive passing disturbance waves, to calculate local instantaneous impurity concentrations based on said simulated boundary conditions, the calculation is made for each fuel rod of the fuel assembly, wherein, for each fuel rod, the method further comprises comparing said calculated local instantaneous impurity concentration to a crud compound precipitation limit, and during the time said concentration is higher than said precipitation limit, crud is considered to have occurred. In a related simulation method also base film dryout, clad temperature increase, and drop entrainment from waves, may be determined.
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
G21C 17/022 - Devices or arrangements for monitoring coolant or moderator for monitoring liquid coolants or moderators
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
G21C 21/02 - Manufacture of fuel elements or breeder elements contained in non-active casings
Water filters for industrial installations; debris filters
for industrial installations; water filters for nuclear
power plants; debris filters for nuclear power plants;
nuclear installations.
A tube grid cell (2) for a fuel bundle (8) of a nuclear reactor. The tube grid cell (2) having the length (L), comprises a cell housing (10) which has, along the longitudinal axis A, a lower section (16), an upper section (18) and a middle section (20). The middle section (20) is provided with two pairs of support members (22) and a resilient member (24) configured to generate a resilient force in an inward radial direction, the resilient member is arranged at essentially equal distance from the support members (22), and positioned approximately (120) degrees apart from the support members seen along axis A. The upper section (18) and the lower section (16) have respectively a length L1 and L2 along axis A that is larger than 0.1L and smaller than 0.3L, and is provided with a solid housing wall, having an even thickness and no openings, indentations or protrusions.
C04B 35/515 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides
C04B 35/58 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides based on borides, nitrides or silicides
G21C 3/42 - Selection of substances for use as reactor fuel
G21C 3/18 - Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
Water filters for industrial installations; debris filters for industrial installations, namely filters for preventing solid material debris from reaching machinery in industrial installations; water filters for nuclear power plants; debris filters for nuclear power plants, namely, filters for preventing solid material debris from reaching fuel assemblies in nuclear power plants; nuclear installations, namely, nuclear reactors and nuclear power plants, and atomic piles
A filter (1) for separating particles from a cooling liquid in a nuclear plant is presented. The filter (1) comprises at least one passage (3) with an inner surface, an inlet end (4) and an outlet end (5), wherein the at least one passage (3) is arranged to permit through-flow of the cooling liquid in a main flow direction (MFD) from the inlet end (4) to the outlet end (5). The inner surface of the at least one passage (3) comprises at least one surface section (6) having a structured surface forming a plurality of surface portions (7) facing the main flow direction (MFD) of the cooling liquid and being arranged to catch the particles. Also a fuel assembly (13) for a nuclear plant, comprising a filter (1) is presented.
A fuel assembly, a fuel rod and a cladding tube (11) for a fuel rod for a nuclear reactor are disclosed. The cladding tube comprises a tubular substrate (20) defining an inner space (14) for housing nuclear fuel pellets (10), and a surface layer(21) applied on the tubular substrate. The tubular substrate is made of a zirconium base alloy and has a first thermal expansion coefficient. The surface layer consists an alloy which consists of a major part of main elements comprising Cr and at least one of Nb and Fe, a minor part of zirconium, and possibly a residual part of interstitial elements. The alloy of the surface layer has a second thermal expansion coefficient. The concentrations of the main elements are selected so that the second thermal expansion coefficient is greater than the first thermal expansion coefficient from 20 to at least 1300°C.
A fuel assembly for a boiling water reactor having fuel rods, two or three water rods, a tie plate, spacers, a handle, and a joint arrangement. The joint arrangement is configured to transfer a vertical lifting force from the handle to the water rods. The joint arrangement includes a balancing element arranged between the water rods and the handle. The joint arrangement includes a first joint arranged between the balancing element and the handle and a set of second joints arranged between a respective one of said water rods and said balancing element. The first joint and the set of second joints are configured to allow a rotational movement of said balancing element in relation to said handle as well as in relation to said water rods in order to balance lifting forces in the water rods.
A nuclear fuel pellet for a nuclear reactor is disclosed. The pellet comprises a metallic matrix and ceramic fuel particles of a fissile material dispersed in the metallic matrix. The metallic matrix is an alloy consisting of the principle elements U, Zr, Nb and Ti, and of possible rest elements. The concentration of each of the principle elements in the metallic matrix is at the most 50 molar-%.
A fuel element (10) is configured for being used a nuclear fission reactor. The fuel element comprises a main compound (20) of uranium silicide, and a boron compound (21) designed to absorb neutrons during operation of the nuclear reactor. The main compound and the boron compound have a respective chemistry that permits the main compound and the boron compound to be in contact with each other in the fuel element.
A tubular ceramic component is provided for being used in a nuclear reactor. The component comprises an inner layer (21) of silicon carbide, an intermediate layer (22) of silicon carbide fibres (25, 26) in a fill material (27) of silicon carbide, and an outer layer (23) of silicon carbide. The intermediate layer adjoins the inner layer. The outer layer adjoins the intermediate layer. The silicon carbide of the inner layer, the fill material and the outer layer is doped and comprises at least one dopant in solid solution within crystals of the silicon carbide.
G21C 3/07 - CasingsJackets characterised by their material, e.g. alloys
C04B 35/00 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products
G21C 21/02 - Manufacture of fuel elements or breeder elements contained in non-active casings
25.
Fuel assembly having concentric lower coolant inlet tubes
A fuel assembly for a nuclear reactor having an upstream minor portion defining an upstream end, a main portion, and a downstream minor portion defining a downstream end. Fuel rods extend in a flow interspace permitting a flow of coolant through the fuel assembly in contact with the fuel rods. Two elongated tubes form a respective internal passage extending in parallel with the fuel rods and enclosing a stream of the coolant. Each elongated tube having a bottom, an inlet at the upstream minor portion and an outlet at the downstream minor portion. Each elongated tube having an inlet pipe having an inlet end and an outlet end in the internal passage at a distance from the bottom, thereby forming a space in the internal passage between the outlet end and the bottom.
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 17/10 - Structural combination of fuel element, control rod, reactor core, or moderator structure with sensitive instruments, e.g. for measuring radioactivity, strain
G21C 3/322 - Means to influence the coolant flow through or around the bundles
26.
Filter zones with different filtering efficiencies for a fuel assembly of a nuclear water reactor
A fuel assembly for a nuclear water reactor having an upstream end, a downstream end, and a flow interspace between the upstream and downstream ends. Fuel rods are provided in the flow interspace between the upstream and downstream ends. The flow interspace permits a flow of coolant through the fuel assembly along a flow direction from the upstream end to the downstream end. A filter device is provided to catch debris particles in the flow of coolant. The filter device has a first filter zone for a major part of the flow of coolant, and a second filter zone for a minor part of the flow of coolant. The first filter zone has a first filtering efficiency and the second filter zone has a second filtering efficiency. The second filtering efficiency is higher than the first filtering efficiency.
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 19/307 - Arrangements for introducing fluent material into the reactor coreArrangements for removing fluent material from the reactor core with continuous purification of circulating fluent material, e.g. by extraction of fission products specially adapted for liquids
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
27.
A cladding tube, and a method of manufacturing a cladding tube
A cladding tube (11) for a fuel rod to be used in a nuclear fission reactor, and a method of manufacturing the cladding tube are disclosed. The cladding tube encloses fissile nuclear fuel (10)and comprises a tubular base layer(20) of a zirconium based alloy, and a coating layer (21). The coating layer is applied onto an outer border (20a) of the tubular base layer. The coating layer is formed of an amorphous alloy comprising zirconium and a further element.
A nuclear fuel pellet (10) for a nuclear reactor is disclosed. The pellet comprises a metallic matrix (20) and ceramic fuel particles (21) of a fissile material dispersed in the metallic matrix. The metallic matrix is an alloy consisting of the principle elements U, Zr, Nb and Ti, and of possible rest elements. The concentration of each of the principle elements in the metallic matrix is at the most 50 molar-%.
A fuel assembly for a nuclear reactor, a fuel rod(4) of the fuel assembly, and a ceramic nuclear fuel pellet (10) of the fuel rod are disclosed. The fuel pellet comprises a first fissile material of UB2, The boron of the UB2 is enriched to have a concentration of the isotope 11B that is higher than for natural B.
G21C 3/18 - Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
30.
A SINTERED NUCLEAR FUEL PELLET, A FUEL ROD, A FUEL ASSEMBLY, AND A METHOD OF MANUFACTURING A SINTERED NUCLEAR FUEL PELLET
Disclosed are a sintered nuclear fuel pellet (10), a fuel rod, a fuel assembly and a method of manufacturing the nuclear fuel pellet. The pellet comprises a matrix (20) of UO2 and particles (21) dispersed in the matrix. The particles comprises a uranium-containing material. Each of the particles is encapsulated by a metallic coating. The uranium-containing material has a uranium density that is higher than the uranium density of UO2. The metallic coating consists of at least one metal chosen from the group of Mo, W, Cr, V and Nb.
A core plate assembly for a boiling water reactor, and a method of performing work thereon are disclosed. The core plate assembly comprises a core plate having through-going apertures, and a beam structure comprising parallel first beams and parallel second beams being perpendicular to the first beams. The beams enclose a plurality of rectangular areas each enclosing four of the through-going apertures. Control rod guide tubes are aligned with a respective one of the through-going apertures. A transition pieces is received in a respective one of the control rod guide tubes, and has four passages for communicating with a respective fuel assembly. Each passage permits a coolant flow into the respective fuel assembly. A flow inlet is provided for the coolant into each passage. At least one of the flow inlets has a cross-sectional shape deviating from a circular shape.
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
G21C 1/08 - Heterogeneous reactors, i.e. in which fuel and moderator are separated moderator being highly pressurised, e.g. boiling-water reactor, integral-superheat reactor, pressurised-water reactor
G21C 15/243 - Promoting flow of the coolant for liquids
G21C 5/06 - Means for locating or supporting fuel elements
A fuel assembly for a nuclear power boiling water reactor including a fuel channel defining a central fuel channel axis, fuel rods, each having a central fuel rod axis, at least 3 water channels for non-boiling water, each water channel having a central water channel axis and each water channel having a larger cross-sectional area than the cross-sectional area of (the average) fuel rod. The fuel rods include a first group of full length fuel rods and a second group of shorter fuel rods. The fuel assembly comprises 3 or 4 fuel rods which belong to said second group and which are positioned such that the central fuel rod axis of each of these 3 or 4 fuel rods is closer to the central fuel channel axis than any of the water channel axes of the water channels.
A method and a system includes controlling and monitoring the gas pressure in a nuclear fuel rod during filling of the fuel rod with a gas, and subsequent sealing of the fuel rod. The system includes a control unit and a length measuring system, which control unit is communicatively connected to the length measuring system. The length measuring system is configured to monitor the length of the fuel rod, and the control unit is configured to receive measurements from the length measuring system and to determine the gas pressure inside the fuel rod on the basis of variations of the length of the fuel rod. The method includes positioning an open first end of the fuel rod inside a pressure chamber, allowing gas to enter the fuel rod; pressurizing the gas in the pressure chamber at a first pressure level; closing the fuel rod; and sealing the fuel rod.
A fuel assembly (1) for a nuclear water reactor comprises an upstream end (1a), a downstream end (1b), and a flow interspace (2) between the upstream and downstream ends. Fuel rods (3) are provided in the flow interspace between the upstream and downstream ends. The flow interspace permits a flow of coolant through the fuel assembly along a flow direction (F) from the upstream end to the downstream end. A filter device (19) is provided to catch debris particles in the flow of coolant. The filter device comprises a first filter zone (20) for a major part of the flow of coolant, and a second filter zone (30) for a minor part of the flow of coolant. The first filter zone has a first filtering efficiency and the second filter zone has a second filtering efficiency. The second filtering efficiency is higher than the first filtering efficiency.
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
G21C 19/307 - Arrangements for introducing fluent material into the reactor coreArrangements for removing fluent material from the reactor core with continuous purification of circulating fluent material, e.g. by extraction of fission products specially adapted for liquids
A fuel assembly (1) for a nuclear reactor comprises an upstream minor portion (3) defining an upstream end (1a), a main portion (5), and a downstream minor portion (4) defining a downstream end (1b). Fuel rods (2) extend in a flow interspace (6) permitting a flow of coolant through the fuel assembly in contact with the fuel rods. Two elongated tubes (7) form a respective internal passage extending in parallel with the fuel rods and enclosing a stream of the coolant. Each elongated tube comprises a bottom, an inlet (21) at the upstream minor portion and an outlet (22) at the downstream minor portion. Each elongated tube comprises an inlet pipe (23) having an inlet end (24) and an outlet end (25) in the internal passage at a distance from the bottom, thereby forming a space in the internal passage between the outlet end and the bottom.
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 17/10 - Structural combination of fuel element, control rod, reactor core, or moderator structure with sensitive instruments, e.g. for measuring radioactivity, strain
A method of making a fuel channel for a fuel assembly for a nuclear power boiling water reactor. The method includes providing at least one first sheet of a Zr-based material of a first thickness, and providing at least one second sheet of a Zr-based material of a second thickness which is less than said first thickness. It also includes assembling at least said at least one first sheet and said at least one second sheet, such that a fuel channel is formed and such that said at least one first sheet forms a lower part of the fuel channel. The at least one second sheet forms a higher part of the fuel channel and the lower part is joined with said higher part. The lower part constitutes 20-75% of the length of the fuel channel.
A fuel assembly for a nuclear power boiling water reactor, including: a fuel channel defining a central fuel channel axis, fuel rods, each having a central fuel rod axis, at least 3 water channels for non-boiling water, each water channel having a central water channel axis and each water channel having a larger cross-sectional area than the cross-sectional area of (the average) fuel rod. The fuel rods comprise a first group of full length fuel rods and a second group of shorter fuel rods. The fuel assembly comprises at least 5 fuel rods which belong to said second group and which are positioned such that the central fuel rod axis of each of these at least 5 fuel rods is closer to the central fuel channel axis than any of the water channel axes of the water channels.
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 3/328 - Relative disposition of the elements in the bundle lattice
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
38.
Method of making a nuclear fuel pellet for a nuclear power reactor
2; providing an additive; forming a green pellet, wherein said additive is added either to said nuclear fuel material or to the green pellet; and sintering the green pellet, wherein said additive causes larger grains in the nuclear fuel pellet, and wherein said additive is made of or includes a substance which causes the larger grains and which substantially leaves at least an outer portion of the pellet before and/or during the sintering step, wherein said substance is made of, or comprises, B and/or Cr.
G21C 3/18 - Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
G21C 3/20 - Details of the construction within the casing with coating on fuel or on inside of casingDetails of the construction within the casing with non-active interlayer between casing and active material
39.
Method of making a nuclear fuel pellet for a nuclear power reactor
A method of making a nuclear fuel pellet for a nuclear power reactor. The method includes: providing a nuclear fuel material in powder form, pressing the powder such that a green pellet is obtained; providing a liquid that comprises an additive which is to be added to the green pellet; contacting the green pellet with the liquid so the liquid, with the additive, penetrates into the pellet; and sintering the treated green pellet. The additive is such that larger grains in the nuclear fuel material are obtained with the additive.
A fuel assembly (1) for a boiling water reactor comprising fuel rods (3), two or three water rods (30), a tie plate (4), spacers (6), a handle (10), and a joint arrangement (11, 12, 13, 20-25, 31, 32, 33) is provided. The joint arrangement is configured to transfer a vertical lifting force from the handle to the water rods. The joint arrangement comprises a balancing element (20) arranged between the water rods (30) and the handle (10). The joint arrangement comprises a first joint (13) arranged between the balancing element (20) and the handle (10) and a set of second joints (33) arranged between a respective one of said water rods (30) and said balancing element (20). The first joint (13) and the set of second joints (33) are configured to allow a rotational movement of said balancing element (20) in relation to said handle (10) as well as in relation to said water rods (30) in order to balance lifting forces in the water rods. The first joint (13) and each one of said second joints (33) comprise a pair of spherically rounded joint surfaces (11, 23; 25, 32).
A method and a system (10) is provided for controlling and monitoring the gas pressure in a nuclear fuel rod (1) during filling of the fuel rod (1) with a gas, and subsequent sealing of the fuel rod (1). The system comprises a control unit (12) and a length measuring system (14), which control unit (12) is communicatively connected to the length measuring system (14). The length measuring system (14) is configured to monitor the length of the fuel rod (1), and the control unit (12) is configured to receive measurements from the length measuring system (14) and to determine the gas pressure inside the fuel rod (1) on the basis of variations of the length of the fuel rod (12). The method comprises positioning (101) an open first end (2) of the fuel rod (1) inside a pressure chamber (11), allowing gas to enter the fuel rod 1; pressurizing (103) the gas in the pressure chamber (11) at a first pressure level; closing (105) the fuel rod (1); and sealing (113) the fuel rod (1). Especially, the method comprises monitoring (107) the variation of the length of the fuel rod (1) between the step of closing (105) and the step of sealing (113), and using the length variation as a measure of the gas pressure variation inside the fuel rod (1).
A method of making a fuel channel (10) for a fuel assembly (8) for a nuclear power boiling water reactor comprises: providing at least one first sheet (11) of a Zr-based material of a first thickness (T), providing at least one second sheet (12) of a Zr-based material of a second thickness (t), which is less than said first thickness (T), assembling at least said at least one first sheet (11) and said at least one second sheet (12), such that a fuel channel (10) is formed and such that said at least one first sheet (11) forms a lower part (LP) of the fuel channel (10) and such that said at least one second sheet (12) forms a higher part (HP) of the fuel channel (10) and such that said lower part (LP) is joined with said higher part (HP), wherein said lower part (LP) constitutes 20-75% of the length (L) of the fuel channel (10). The invention also concerns a fuel channel (10) and a fuel assembly (8).
The present invention concerns a fuel assembly (4) for a nuclear power boiling water reactor, comprising: a fuel channel (6) defining a central fuel channel axis (8), fuel rods (10), each having a central fuel rod axis (12), at least 3 water channels (14) for non-boiling water, each water channel having a central water channel axis (16) and each water channel having a larger cross-sectional area than the cross-sectional area of (the average) fuel rod (10). The fuel rods (10) comprise a first group of full length fuel rods and a second group of shorter fuel rods. The fuel assembly (4) comprises 3 or 4 fuel rods which belong to said second group and which are positioned such that the central fuel rod axis (12) of each of these 3 or 4 fuel rods is closer to the central fuel channel axis (8) than any of the water channel axes (16) of the water channels (14).
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
G21C 3/328 - Relative disposition of the elements in the bundle lattice
A method for cleaning contaminated gas from a containment(1) of a nuclear site is disclosed. The method comprises providing a wet scrubber(3), comprising a vessel (5) containing a scrubber solution, activating the wet scrubber by introducing said contaminated gas in the scrubber solution in the vessel at a position beneath a surface of said scrubber solution, bringing said contaminated gas into contact with said scrubber solution, so that the scrubber solution absorbs or dissolves contaminants of said contaminated gas, thereby producing a cleaned gas, and releasing said cleaned gas from the vessel. A phosphine additive comprising a phosphine or a mixture of phosphines is supplied to the wet scrubber in order to be mixed with the aqueous scrubber solution at least when the wet scrubber is activated.
A fuel assembly for a boiling water reactor, comprises fuel rods (2), a tie plate (3), a handle device (4), and at least two water rods (7) attached to the tie plate and to the handle device. A plurality of spacers (8a, 8b), define first passages (8') for some of the fuel rods, and second passages (8") for the water rods. Each water rod comprises a tube part (7a) attached to the tie plate, and a solid part (7b) attached to the handle device. The tube part permits a flow of coolant. The spacers comprise primary spacers (8a) and a secondary spacer (8b). The primary spacers are attached to the tube parts. The tie plate, the water rods, the primary spacers and the handle device form a support structure carrying the weight of the fuel rods. The secondary spacer is positioned at the solid part of the respective water rod.
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
The present invention concerns a fuel assembly (4) for a nuclear power boiling water reactor, comprising: a fuel channel (6) defining a central fuel channel axis (8), fuel rods (10), each having a central fuel rod axis (12), at least 3 water channels (14) for non-boiling water, each water channel having a central water channel axis (16) and each water channel having a larger cross-sectional area than the cross-sectional area of (the average) fuel rod (10). The fuel rods (10) comprise a first group of full length fuel rods and a second group of shorter fuel rods. The fuel assembly (4) comprises at least 5 fuel rods which belong to said second group and which are positioned such that the central fuel rod axis (12) of each of these at least 5 fuel rods is closer to the central fuel channel axis (8) than any of the water channel axes (16) of the water channels (14).
G21C 3/322 - Means to influence the coolant flow through or around the bundles
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
G21C 3/328 - Relative disposition of the elements in the bundle lattice
47.
METHOD OF MAKING A NUCLEAR FUEL PELLET FOR A NUCLEAR POWER REACTOR
The present invention concerns a method of making a nuclear fuel pellet for a nuclear power reactor. The method comprising the following steps: providing a nuclear fuel material in powder form, pressing the powder such that a so-called green pellet is obtained, providing a liquid that comprises an additive which is to be added to the green pellet, contacting the green pellet with the liquid such that the liquid, with the additive, penetrates into the pellet, sintering the so treated green pellet, wherein the additive is such that larger grains in the nuclear fuel material are obtained with the additive.
The present invention concerns a method of making a nuclear fuel pellet for a nuclear power reactor. The method comprises the following steps: providing a nuclear fuel material in powder form, providing an additive, forming a so-called green pellet, wherein said additive is added either to said nuclear fuel mate- rial in powder form or to the green pellet, sintering the green pellet, wherein said additive is such that it causes larger grains in the nuclear fuel pellet, and wherein said additive is made of or includes a substance which causes the larger grains and which substantially leaves at least an outer portion of the pellet before and/or during the sintering step.
A fuel channel for a nuclear power boiling water reactor is configured to include a bundle of fuel rods with nuclear fuel. The fuel channel is made of a sheet material and has a plurality of sides which have an elongated shape and which are connected to each other such that a corner with an elongated shape is formed where two adjacent sides meet. In one or more corners, the sheet materials from the two adjacent sides overlap with each other such that there is a corner region with double sheet material consisting of the overlapping sheet material from one of the two sides and the overlapping sheet material from the other of the two sides.
G21C 3/326 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements comprising fuel elements of different compositionComprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods
A device configured to fit a first object (1) together with a second object (2) in a nuclear environment comprises means (3) configured to move at least said first object with respect to said second object for fitting these objects together and a controllable arrangement (4) configured to control the movement of at least said first object when fitting the objects together. Means (10-12) is configured to create a representation of at least those portions of said two objects which are to be brought together when fitting the objects together. Means (9) is also configured to utilize this information in real time for making it possible to control said arrangement (4) for controlling the movement of at least said first object when fitting the objects together by means of said representation.
G21C 19/20 - Arrangements for introducing objects into the pressure vesselArrangements for handling objects within the pressure vesselArrangements for removing objects from the pressure vessel
The present invention relates to a filter arrangement which comprises a distribution pipe (12) receiving the gaseous medium from the inlet opening (1 1 ) and leads it through a longitudinal flow passage inside the container (10), a plurality of filter units (18) which are mounted around the distribution pipe (12) in different positions which each comprises a filter material (23) and passages receiving the gaseous medium from the distribution pipe (12) and leading it through the filter material (23) and in a substantially transverse direction radially outwardly in the container (10), and outlet passages (26) receiving the gaseous medium in a periphery area of the container (10) after it has passed through the filter units (18) and leading it towards the outlet opening (13).
B01D 53/04 - Separation of gases or vapoursRecovering vapours of volatile solvents from gasesChemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases or aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
B01D 29/41 - Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups Filtering elements therefor with hollow discs side by side on, or around, one or more tubes, e.g. of the leaf type mounted transversely on the tube
B01D 46/00 - Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
B01D 46/12 - Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces in multiple arrangements
B01D 46/24 - Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
The invention concerns a fuel channel (10) for a nuclear power boiling water reactor. The fuel channel (10) is configured to include a bundle of fuel rods (15) with nuclear fuel. The fuel channel (10) is made of a sheet material and has a plurality of sides (11 -14) which have an elongated shape and which are connected to each other such that a corner (21 -24) with an elongated shape is formed where two adjacent sides meet. In at least one corner (21) the sheet materials from the two adjacent sides (11, 12) overlap with each other such that there is a corner region with double sheet material consisting of the overlapping sheet material (11c) from one (11) of the two sides and the overlapping sheet material (12c) from the other (12) of the two sides. The invention also concerns a fuel assembly for a nuclear power boiling water reactor.
A method of welding a fuel rod includes the following steps. An end plug and a cladding tube of the fuel rod are brought together to abut each other, and welded by applying a laser beam directed to a welding zone to melt material of the end plug and the cladding tube. The welding is sensed by sensing radiation within a first wavelength range, which includes the wavelength of the laser beam coming from reflections from the welding zone, sensing radiation within a second wavelength range different from the first wavelength range, which includes infrared radiation from melted material, and sensing radiation within a third wavelength range different from the first and second wavelength ranges, which includes radiation from plasma. The welding and melting of material is monitored by monitoring the sensed radiations.
A device for submersibly cleaning surfaces inside a nuclear reactor includes a pump and a nozzle connected to said pump. The nozzle is arranged to face surfaces to be cleaned. The device includes cleaning means capable of removing debris on surfaces to be cleaned. The device includes adjustable flotation means, capable of adjusting the flotation capability of the device depending on a type of cleaning application.
G21C 19/00 - Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
The present invention relates to a device designed to capture the detached particles from an object being processed by the tool. The device includes an inlet opening to an internal space. The device includes guiding means configured to lead particles, which is detached during a machining process, the inner space of the container via the inlet opening and the inner space comprises a first material that has a consistency such that it has the ability to receive and retain detached particles, which are led into the inner space during the machining process.
B23Q 11/02 - Devices for removing scrap from the cutting teeth of circular cutters
B65B 1/28 - Controlling escape of air or dust from containers or receptacles during filling
B23Q 11/00 - Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling workSafety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
The invention refers to a fuel assembly comprising a lower end structure, an upper end structure including a top nozzle (5), a plurality of fuel rods and a plurality of guide thimbles (3). The top nozzle includes a passageway and an annular groove (10) in said passageway. A sleeve (11) is provided for attaching the guide thimble (3) to the top nozzle (5). The sleeve has at least three slots (12) and includes at least three bulges (13). Each bulge (13) has two ends and extends between two of the slots (12). At least one of the ends of the bulge (13) extends to a position at a distance (d) from the respective slot (12). The invention also refers to a guide thimble device (9) for use in a fuel assembly.
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
The present invention relates to a device for submersibly cleaning surfaces inside a nuclear reactor, comprising a pump (14), a nozzle (12) connected to said pump (14) and arranged to face surfaces to be cleaned, cleaning means capable of removing any debris on surfaces to be cleaned. The invention is characterised in that it further comprises adjustable flotation means (50), capable of adjusting the flotation capability of the device depending on cleaning application.
G21C 1/14 - Heterogeneous reactors, i.e. in which fuel and moderator are separated moderator being substantially not pressurised, e.g. swimming-pool reactor
G21C 17/01 - Inspection of the inner surfaces of vessels
The invention concerns a control rod configured for a nuclear power light water reactor of the BWR or PWR kind. The control rod contains absorber material. At least 50%, with respect to weight, of the absorber material that is in the control rod is in the form of hafnium hydride. The invention also concerns the use of such a control rod during operation in a nuclear power light water reactor of the BWR or PWR kind.
A control rod for a nuclear boiling water reactor is described. The control rod has a longitudinal centre axis and control rod blades, each control rod blade having a first and a second side and being substantially parallel to the longitudinal center axis. Each control rod blade comprises an absorber material which extends from a first absorber end to a second absorber end, the distance between the first absorber end and the second absorber end defining an active length. The control rod blades are provided with distance means on the first and second sides of the control rod blades, the distance means extending a distance of at least a third of the active length of the control rod blade.
A method of welding a fuel rod (1) comprises the following steps. An end plug (3) and a cladding tube (2) of the fuel rod are brought together to abut each other, and welded by applying a laser beam directed to a welding zone (36) to melt material of the end plug and the cladding tube. The welding is sensed by sensing radiation within a first wavelength range, which includes the wavelength of the laser beam coming from reflections from the welding zone, sensing radiation within a second wavelength range different from the first wavelength range, which includes infrared radiation from melted material, and sensing radiation within a third wavelength range different from the first and second wavelength ranges, which includes radiation from plasma. The welding and melting of material is monitored by monitoring the sensed radiations.
The present invention relates to an apparatus and a method for cleaning a nuclear fuel element in a liquid filled space. The fuel element comprises an inner space with an opening. The apparatus comprises a connecting element, which is adapted to be connected to a portion of the fuel element, which comprises said opening and flow means, which is adapted to create, at least during a part of a cleaning process of the fuel element, a liquid flow through inner space of the fuel element via said opening.
G21C 19/20 - Arrangements for introducing objects into the pressure vesselArrangements for handling objects within the pressure vesselArrangements for removing objects from the pressure vessel
G21C 17/06 - Devices or arrangements for monitoring or testing fuel or fuel elements outside the reactor core, e.g. for burn-up, for contamination
A fuel assembly for a nuclear boiling water reactor is provided. The reactor comprises a plurality of such fuel assemblies and a plurality of control rods. Each control rod is insertable between the fuel assemblies. The fuel assembly has a longitudinal center axis and includes a plurality of elongated fuel rods and an elongated channel box. The channel box has inner sides, facing the fuel rods, and outer sides. Each inner and outer side has a longitudinal center line extending in parallel with the center axis and along the length of the channel box. A number of protrusions are distributed along the center line of at least two of the outer sides. The protrusions are configured to ensure a minimum distance between the outer side and an adjacent control rod and to enable the control rod to easily slide over and on top of the protrusions.
The present invention relates to a device designed to capture the detached particles (3b) from an object (3) being processed by the tool (1). The device comprises an inlet opening (8) to an internal space (7). The device comprises guiding means (10, 10b) configured to lead particles (3), which is detached during a machining process, the inner space (7) of the container (6) via the inlet opening (8) and the inner space (7) comprises a first materials (13) that has a consistency such that it has the ability to receive and retain detached particles (3b), which are led into the inner space (7) during the machining process.
B23Q 11/00 - Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling workSafety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
B23B 45/00 - Hand-held or like portable drilling machines, e.g. drill gunsEquipment therefor
B23B 47/00 - Constructional features of components specially designed for boring or drilling machinesAccessories therefor
G21C 19/30 - Arrangements for introducing fluent material into the reactor coreArrangements for removing fluent material from the reactor core with continuous purification of circulating fluent material, e.g. by extraction of fission products
65.
A FUEL ASSEMBLY, A GUIDE THIMBLE DEVICE AND USE OF THE GUIDE THIMBLE DEVICE
The invention refers to a fuel assembly comprising a lower end structure, an upper end structure including a top nozzle (5), a plurality of fuel rods and a plurality of guide thimbles (3). The top nozzle includes a passageway and an annular groove (10) in said passageway. A sleeve (1 1 ) is provided for attaching the guide thimble (3) to the top nozzle (5). The sleeve has at least three slots (12) and includes at least three bulges (13). Each bulge (13) has two ends and extends between two of the slots (12). At least one of the ends of the bulge (13) extends to a position at a distance (d) from the respective slot (12). The invention also refers to a guide thimble device (9) for use in a fuel assembly.
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
The invention concerns a control rod configured for a nuclear power light water reactor of the BWR or PWR kind. The control rod contains absorber material. At least 50%, with respect to weight, of the absorber material that is in the control rod is in the form of hafnium hydride. The invention also concerns the use of such a control rod during operation in a nuclear power light water reactor of the BWR or PWR kind.
A fuel channel (5) for a fuel element (1) of a fission reactor, where the fuel element comprises an inlet (9), an outlet (11) and a plurality of elongated fuel rods (3), which fuel rods each comprises a nuclear fuel and are adapted to transfer energy to a streaming medium during operation of the fission reactor. The fuel channel comprises a casing (7) adapted to surround the fuel rods between the inlet and the outlet. The casing is adapted during operation of the fission reactor to guide the streaming medium along the fuel rods from the inlet to the outlet and be subjected to irradiation from the fuel rods. The casing is manufactured from a ceramic material.
C04B 35/565 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides based on carbides based on silicon carbide
A control rod (4) for a nuclear boiling water reactor (1) is described. The control rod (4) has a longitudinal centre axis (8) and control rod blades (4a), each control rod blade (4a) having a first and a second side and being substantially parallel to the longitudinal centre axis (8). Each control rod blade (4a) comprises an absorber material (9) which extends from a first absorber end (11) to a second absorber end (12), the distance between the first absorber end (11) and the second absorber end (12) defining an active length (L). The control rod blades (4a) are provided with distance means (13) on the first and second sides of the control rod blades (4a), the distance means (13) extending a distance of at least a third of the active length (L) of the control rod blade (4a).
A method of manufacturing an optimized sheet metal (1) of a zirconium based alloy is described, which optimized sheet metal (1) defines a sheet plane (BA). The method comprises the steps of providing a sheet metal (2) of a zirconium based. alloy, subjecting the sheet metal (2) to at least a preparing cold rolling and a final cold rolling, wherein the preparing cold rolling and the final cold rolling are both performed in a common rolling direction, and heat treating the sheet metal (1) between the preparing cold rolling and the final cold rolling so that the zirconium based alloy is partially re-crystallized. A method of manufacturing a spacer grid using an optimized sheet metal (1) according to the invention is also described.
B23P 19/00 - Machines for simply fitting together or separating metal parts or objects, or metal and non-metal parts, whether or not involving some deformationTools or devices therefor so far as not provided for in other classes
70.
A NEUTRON ABSORBING COMPONENT AND A METHOD FOR PRODUCING OF A NEUTRON ABSORBING COMPONENT
The invention regards a neutron absorbing component (1) and a method for manufacturing a neutron absorbing component. The neutron absorbing component comprises a core (2) consisting of a first material, a layer (3) consisting of a second material. The layer encloses a least partly the core and is adapted to protect the core from an outer surrounding. The first material has a higher neutron absorption capability than the second material. The neutron absorbing component is manufactured by sintering in such a way that an intermediate layer (4) is formed between the core and the layer. The intermediate layer has a material gradient that comprises a decrease of the concentration of the first material from the core to the layer and an increase of the concentration of the second material from core to the layer.
G21C 19/40 - Arrangements for preventing occurrence of critical conditions, e.g. during storage
C04B 37/00 - Joining burned ceramic articles with other burned ceramic articles or other articles by heating
B22F 7/00 - Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting
B32B 15/04 - Layered products essentially comprising metal comprising metal as the main or only constituent of a layer, next to another layer of a specific substance
C23C 12/00 - Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
C23C 24/08 - Coating starting from inorganic powder by application of heat or pressure and heat
C22C 1/05 - Mixtures of metal powder with non-metallic powder
Reactor component adapted to be used in fission reactors comprising a core (2) consisting of a first material and a layer (3) consisting of a second material. The layer (3) encloses at least partly the core (2). The reactor component is characterized in that the component (1) comprises and intermediate layer (4) between the core (2) and the layer (3). The intermediate layer (4) has a material gradient that comprises a decrease of the concentration of the first material from the core (2) to the layer (3) and an increase of the concentration of the second material from the core (2) to the layer (3).
B22F 7/00 - Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting
B32B 15/04 - Layered products essentially comprising metal comprising metal as the main or only constituent of a layer, next to another layer of a specific substance
C04B 37/00 - Joining burned ceramic articles with other burned ceramic articles or other articles by heating
C22C 1/05 - Mixtures of metal powder with non-metallic powder
C23C 12/00 - Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
C23C 24/08 - Coating starting from inorganic powder by application of heat or pressure and heat
72.
A NEUTRON ABSORBING COMPONENT AND A METHOD FOR PRODUCING A NEUTRON ABSORBING COMPONENT
The invention relates to a fuel component (1) and a method for manufacturing of a fuel component (1). The fuel component (1) is adapted to be used in fission reactors. The fuel component (1) comprises a core (2) consisting of a first material, and a layer (3) consisting of a second material. The layer (3) encloses at least partly the core (2). The first material comprises a fissile substance. The fuel component (1) comprises an intermediate layer (4) between the core (2) and the layer (3). The intermediate layer (4) has a material gradient that comprises a decrease of the concentration of the first material from the core (2) to the layer (3) and an increase of the concentration of the second material from the core (2) to the layer (3).
G21C 21/02 - Manufacture of fuel elements or breeder elements contained in non-active casings
B22F 7/00 - Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting
B32B 15/04 - Layered products essentially comprising metal comprising metal as the main or only constituent of a layer, next to another layer of a specific substance
C04B 37/00 - Joining burned ceramic articles with other burned ceramic articles or other articles by heating
C22C 1/05 - Mixtures of metal powder with non-metallic powder
C23C 12/00 - Solid state diffusion of at least one non-metal element other than silicon and at least one metal element or silicon into metallic material surfaces
C23C 24/08 - Coating starting from inorganic powder by application of heat or pressure and heat
73.
NUCLEAR FUEL, NUCLEAR FUEL ELEMENT, NUCLEAR FUEL ASSEMBLY AND A METHOD MANUFACTURING NUCLEAR FUEL
The invention refers to nuclear fuel (10), a fuel element (4), a fuel assembly (1) and a method of manufacturing nuclear fuel. The nuclear fuel is adapted for use in a water cooled nuclear reactor, including light water reactors LWR, such as Boiling Water Reactors BWR and Pressure Water Reactors PWR. The nuclear fuel comprises an uranium- containing compound consisting of UN. The uranium content of the uranium- containing compound comprises less than 10% by weight of the isotope 235U. The nuclear fuel comprises an additive substantially consisting of at least one element, in elementary form or as a compound, selected from the group consisting of Zr, Mo, Si, Al, Nb and U.
wherein through the method at least the hydride content of the fuel channel (14) at said places is determined. The method can be used in order to find out how shadow corrosion from a neighboring control rod influences the properties of the fuel channel (14).
G21C 17/06 - Devices or arrangements for monitoring or testing fuel or fuel elements outside the reactor core, e.g. for burn-up, for contamination
G01N 27/72 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables
G01N 27/90 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating magnetic variables for investigating the presence of flaws using eddy currents
The present invention relates to an apparatus (9) and a method for cleaning a nuclear fuel element (8) in a liquid filled space (2). The fuel element (8) comprises an inner space (8a) with an opening (8b). The apparatus (9) comprises a connecting element (11), which is adapted to be connected to a portion of the fuel element (8), which comprises said opening (8b) and flow means (16, 32), which is adapted to create, at least during a part of a cleaning process of the fuel element (8), a liquid flow through inner space of the fuel element (8a) via said opening (8b).
The invention relates to a final, ready to use, spacer grid for a nuclear boiling water reactor. The final spacer grid comprises: i) a spacer grid structure made of an alloy that has been formed and assembled such that it constitutes a spacer grid, and ii) an outer oxide coating on the surface of the spacer grid structure. Said alloy is a Ni base alloy that consists of the following: (table) The invention also relates to a method of manufacturing the final spacer grid according to the invention.
The invention concerns a method of monitoring the operation of a reactor of a nuclear plant. The reactor is operated at a given total reactor power during a normal fuel operation cycle. The radioactivity level in the off-gas stream is continuously measured to detect a possible release of fission gases from the fuel rods as a consequence of a fuel leakage due to a defect on the cladding of any of the fuel rods in any of the fuel assemblies. An instantaneous power distribution is regularly established in the core and a power distribution pattern over time is established based on the instantaneous power distributions. The release of fission gases and the established power distribution pattern are then combined and correlations between changes in the release of fission gases and in the power distribution pattern are observed in order to determine a position of the defect.
A water reactor fuel cladding tube (4) is described. The tube (4) comprises an outer layer (6) of a first zirconium based alloy and has metallurgically bonded thereto an inner layer (7) of a second zirconium based alloy. The inner layer protects (7) the cladding tube (4) against stress corrosion cracking. The second zirconium based alloy comprises tin as an alloying material, and each one of the zirconium based alloys comprises at least 96 percent by weight zirconium. The first zirconium based alloy comprises at least 0.1 percent by weight niobium. A method of manufacturing the cladding tube (4) is also described and comprises the step of co-extruding two tubes of different zirconium based alloys to produce the cladding tube (4).
A fuel assembly (3) for a nuclear boiling water reactor (1) is provided. The reactor comprises a plurality of such fuel assemblies and a plurality of control rods (4). Each control rod is insertable between the fuel assemblies. The fuel assembly has a longitudinal center axis (z) and includes a plurality of elongated fuel rods (7) and an elongated channel box (6). The channel box has inner sides (8), facing the fuel rods, and outer sides (9). Each inner and outer side has a longitudinal center line (y) extending in parallel with the center axis and along the length of the channel box. A number of protrusions (12) are distributed along the center line of at least two of the outer sides. The protrusions are configured to ensure a minimum distance (d2) between the outer side and an adjacent control rod and to enable the control rod to easily slide over and on top of the protrusions.
The invention refers to a device and a method for handling a fuel assembly (3), which comprises a number of fuel rods extending between a lower part and an upper part of the fuel assembly, a debris filter located in the lower part of the fuel assembly and a casing surrounding the fuel rods. The device comprises a lifting device (15) for engaging, during a lifting operation, a fuel assembly located in a reactor vessel (1) and lifting the fuel assembly upwards and out from the reactor vessel. A conduit member is connected to the upper part of the fuel assembly. A pump (32) creates a flow of water through the conduit member and the fuel assembly during the lifting operation. The flow has such a size that possible debris particles contained in and/or immediately beneath the debris filter at least are retained in and/or immediately beneath the debris filter during the lifting operation.
G21C 19/00 - Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
G21C 19/04 - Means for controlling flow of coolant over objects being handledMeans for controlling flow of coolant through channel being serviced
G21C 19/10 - Lifting devices or pulling devices adapted for co-operation with fuel elements or with control elements
81.
Mechanical assembly for securing the structural integrity of a pipe joint
A mechanical securing assembly (40) is adapted to secure the structural integrity of a flow passage formed by at least a first pipe part (41) and a second pipe part (42). The assembly comprises a connecting member (43), a first fastening member (44), attached to the connecting member and adapted to secure the connecting member to the first pipe part, and a second fastening member (45), attached to the connecting member and adapted to secure the connecting member to the second pipe part. The connecting member comprises a spring element (46) exerting a force pulling the first fastening member and the second fastening member towards each other along a primary axis (y), and thus being adapted to force the first pipe part and the second pipe part towards each other. The spring element is extendable along the primary axis by a compression of the spring element along a secondary axis forming an angle to the primary axis.
A method of operating a nuclear reactor is disclosed. The reactor (1) encloses a core having a plurality of fuel rods (9). Each fuel rod (9) includes a cladding and fuel pellets of a nuclear fuel. The fuel pellets are arranged in an inner space of the cladding leaving a free volume comprising an upper plenum, a lower plenum and a pellet-cladding gap. The reactor is operated at a normal power and a normal inlet sub-cooling during a normal state. The reactor is monitored for detecting a defect on the cladding of any of the fuel rods. The operation of the reactor is changed to a particular state after detecting such a defect. The particular state permits an increase of the free volume in the defect fuel rod. The reactor is operated at the particular state during a limited time period, after which the reactor is operated at the normal state.
G21C 17/022 - Devices or arrangements for monitoring coolant or moderator for monitoring liquid coolants or moderators
G21C 7/08 - Control of nuclear reaction by application of neutron-absorbing material, i.e. material with absorption cross-section very much in excess of reflection cross-section by displacement of solid control elements, e.g. control rods
G21C 7/32 - Control of nuclear reaction by varying flow of coolant through the core
A method for production of spacers to hold at least a number of elongated fuel rods (5) in a fuel unit (20) for placement in a re-actor (1) is described. The method comprises the steps of providing at least two spacers (30), to provide a set of mandrels (40) comprising a number of mandrels (42), to arrange at least two spacers (30) with one on top of the other on the set of mandrels (40), and to heat treat the spacers (30) when they are arranged on the set of mandrels (40) so that the cells (31) in the spacers (30) adapts to the mandrels (42).
B23K 31/02 - Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by any single one of main groups relating to soldering or welding
84.
METHOD COMPRISING MEASUREMENT ON FUEL CHANNELS OF FUEL ASSEMBLIES FOR NUCLEAR BOILING WATER REACTORS
The invention concerns a method comprising measurement on a fuel channel (14) of fuel assemblies (8) for nuclear boiling water reactors. The method comprises that: the measurement is done by the use of a non-destructive inductive eddy current measurement method, the measurement is done on a fuel channel (14) which has been used at least a certain time during operation in the core of a nuclear boiling water reactor, the measurement is done when the fuel channel (14) is located in water, the measurement is done on different places on the fuel channel (14), wherein through the method at least the hydride content of the fuel channel (14) at said places is determined. The method can be used in order to find out how shadow corrosion from a neighbouring control rod influences the properties of the fuel channel (14).
The invention concerns a method of monitoring the operation of a reactor (1 ) of a nuclear plant. The reactor is operated at a given total reactor power during a normal fuel operation cycle. The radioactivity level in the off-gas stream (8) is continuously measured to detect a possible release of fission gases from the fuel rods (9) as a consequence of a fuel leakage due to a defect (13) on the cladding (10) of any of the fuel rods in any of the fuel assemblies (3). An instantaneous power distribution (PDI) is regularly established in the core (2) and a power distribution pattern (PDp) over time is established based on the instantaneous power distributions. The release of fission gases and the established power distribution pattern are then combined and correlations between changes in the release of fission gases and in the power distribution pattern are observed in order to determine a position of the defect.
The invention relates to a final, ready to use, spacer grid for a nuclear boiling water reactor. The final spacer grid comprises: i) a spacer grid structure made of an alloy that has been formed and assembled such that it constitutes a spacer grid, and ii) an outer oxide coating on the surface of the spacer grid structure. Said alloy is a Ni base alloy that consists of the following:(table) The invention also relates to a method of manufacturing the final spacer grid according to the invention.
i(z)) for said fuel rod (i). A processor is configured for automatically determining the R-factor. A computer program product, a method of determining the critical power for a bundle of fuel rods, a nuclear energy plant, and a method of operating a nuclear energy plant are also described.
G21C 19/00 - Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
A method for manufacturing a sheet metal for use in a boiling water nuclear reactor and such a sheet metal. The method includes providing a material of a zirconium alloy that includes zirconium, and whose main alloying materials include niobium. The material is annealed so that essentially all niobium containing secondary phase particles are transformed to β-niobium particles.
A clamp assembly and a method for applying a clamp assembly ( 15 ) at a joint between a first pipe (17) with a length axis (18) and a second pipe (19) with a length axis (20), for securing the two pipes ( 17 , 19) to each other, is described. The clamp assembly (15) comprises a first clamp element (21) and a second clamp element ( 22 ) , wherein at least the first clamp element (21) comprises a first stud means (25) and a second stud means (27). The method comprises the steps of using the clamp assembly as a tool to form grooves by electrical discharge machining and arranging the clamp assembly (15) around the pipes (17, 19) partly in the grooves.
F16L 55/172 - Devices for covering leaks in pipes or hoses, e.g. hose-menders from outside the pipe by means of rings, bands or sleeves pressed against the outside surface of the pipe or hose the ring, band or sleeve being tightened by a tangentially arranged threaded pin and a nut
G21C 15/25 - Promoting flow of the coolant for liquids using jet pumps
90.
A METHOD FOR OPERATING A REACTOR OF A NUCLEAR PLANT
A method of operating a nuclear reactor is disclosed. The reactor (1) encloses a core having a plurality of fuel rods (9). Each fuel rod (9) includes a cladding and fuel pellets of a nuclear fuel. The fuel pellets are arranged in an inner space of the cladding leaving a free volume comprising an upper plenum, a lower plenum and a pellet-cladding gap. The reactor is operated at a normal power and a normal inlet sub-cooling during a normal state. The reactor is monitored for detecting a defect on the cladding of any of the fuel rods. The operation of the reactor is changed to a particular state after detecting such a defect. The particular state permits an increase of the free volume in the defect fuel rod. The reactor is operated at the particular state during a limited time period, after which the reactor is operated at the normal state.
G21C 3/17 - Means for storage or immobilisation of gases in fuel elements
G21C 3/18 - Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
G21C 7/08 - Control of nuclear reaction by application of neutron-absorbing material, i.e. material with absorption cross-section very much in excess of reflection cross-section by displacement of solid control elements, e.g. control rods
G21C 7/32 - Control of nuclear reaction by varying flow of coolant through the core
91.
METHOD FOR PRODUCTION OF SPACERS FOR A NUCLEAR REACTOR
A method for production of spacers to hold at least a number of elongated fuel rods (5) in a fuel unit (20) for placement in a re- actor (1 ) is described. The method comprises the steps of pro¬ viding at least two spacers (30), to provide a set of mandrels (40) comprising a number of mandrels (42), to arrange at least two spacers (30) with one on top of the other on the set of mandrels (40), and to heat treat the spacers (30) when they are arranged on the set of mandrels (40) so that the cells (31 ) in the spacers (30) adapts to the mandrels (42).
A method of manufacturing an optimized sheet metal (1 ) of a zirconium based alloy is described, which optimized sheet metal (1 ) defines a sheet plane (BA). The method comprises the steps of providing a sheet metal (2) of a zirconium based alloy, subjecting the sheet metal (2) to at least a preparing cold rolling and a final cold rolling, wherein the preparing cold rolling and the final cold rolling are both performed in a common rolling direction, and heat treating the sheet metal (1 ) between the preparing cold rolling and the final cold rolling so that the zirconium based alloy is partially re- crystallized. A method of manufacturing a spacer grid using an optimized sheet metal (1 ) according to the invention is also described.
A mechanical securing assembly (40) is adapted to secure the structural integrity of a flow passage formed by at least a first pipe part (41) and a second pipe part (42). The assembly comprises a connecting member (43), a first fastening member (44), attached to the connecting member and adapted to secure the connecting member to the first pipe part, and a second fastening member (45), attached to the connecting member and adapted to secure the connecting member to the second pipe part. The connecting member comprises a spring element (46) exerting a force pulling the first fastening member and the second fastening member towards each other along a primary axis (y), and thus being adapted to force the first pipe part and the second pipe part towards each other. The spring element is extendable along the primary axis by a compression of the spring element along a secondary axis forming an angle to the primary axis.
A clamp assembly (19) for securing a thermal sleeve (9) and an elbow (11) in a pipe assembly in a nuclear reactor (1), and a nuclear reactor (1) with such a clamp assembly is described. The clamp assembly comprises a sleeve clamp (37) adapted to be arranged surrounding the elbow (11) at the first joint (17) between the elbow (11) and the thermal sleeve (9), and comprising sleeve support means (25) adapted to extend across the first joint (17) between the elbow (11) and the thermal sleeve (9). The clamp assembly (19) comprises at least one clamp arm (27) with a first end being arranged to rest against at least one of the core shroud (7) and the core plate support ring (6), to provide a support for the positioning of the sleeve clamp (37).
G21C 13/032 - Joints between tubes and vessel walls, e.g. taking into account thermal stresses
F16L 3/08 - Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets substantially surrounding the pipe, cable or protective tubing
F16L 3/10 - Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets substantially surrounding the pipe, cable or protective tubing divided, i.e. with two members engaging the pipe, cable or protective tubing
G21C 15/22 - Structural association of coolant tubes with headers or other pipes, e.g. in pressure tube reactors
G21C 15/25 - Promoting flow of the coolant for liquids using jet pumps
G21C 9/00 - Emergency protection arrangements structurally associated with the reactor
The invention refers to a device and a method for handling a fuel assembly (3), which comprises a number of fuel rods extending between a lower part and an upper part of the fuel assembly, a debris filter located in the lower part of the fuel assembly and a casing surrounding the fuel rods. The device comprises a lifting device (15) for engaging, during a lifting operation, a fuel assembly located in a reactor vessel (1) and lifting the fuel assembly upwards and out from the reactor vessel. A conduit member is connected to the upper part of the fuel assembly. A pump (32) creates a flow of water through the conduit member and the fuel assembly during the lifting operation. The flow has such a size that possible debris particles contained in and/or immediately beneath the debris filter at least are retained in and/or immediately beneath the debris filter during the iifting operation.
A water reactor fuel cladding tube (4) is described. The tube (4) comprises an outer layer (6) of a first zirconium based alloy and has metallurgically bonded thereto an inner layer (7) of a second zirconium based alloy. The inner layer protects (7) the cladding tube (4) against stress corrosion cracking. The second zirconium based alloy comprises tin as an alloying material, and each one of the zirconium based alloys comprises at least 96 percent by weight zirconium. The first zirconium based alloy comprises at least 0.1 percent by weight niobium. A method of manufacturing the cladding tube (4) is also described and comprises the step of co-extruding two tubes of different zirconium based alloys to produce the cladding tube (4).
The present invention refers to a control rod device for a nuclear reactor (1) having a core which comprises nuclear fuel and which is arranged to permit through-flowing of water. The control rod device (2) comprises a moveable control rod member (6) and a stationary guide member (7). The control rod member may be displaced axially into the core and comprises a control rod (8) with a neutron-absorbing substance. The control rod member is displaceable in the guide member between a first end position outside the core and a second end position in the core. A retarding device is arranged to retard the control rod member when it approaches the second end position. The retarding device comprises an eddy current brake having a first eddy current unit (31) on one of the control rod member and the guide member and a second eddy current unit (32) on the other of the control rod member and the guide member.
The invention also concerns a use of a sheet that is produced and treated according to this method, and to methods and fuel assemblies of which said sheet forms a part.
09 - Scientific and electric apparatus and instruments
Goods & Services
computers and parts therefor; computer software and programs for the monitoring, measuring, and control of energy and industrial manufacturing plants and municipal, commercial and vehicular transportation
