Abstract: Disclosed are systems and methods for loading and transferring spent nuclear fuel. In one embodiment, among others, the system comprises a transfer cask that contains spent nuclear fuel and shields radioactivity of the spent nuclear fuel, and an immersion tank that receives transfer casks within. The immersion tank has fluid that is circulated in the immersion tank, thereby cooling and providing shielding for the received transfer cask containing the spent nuclear fuel.

Abstract: The invention relates to a storage device (1) for the storing and/or transporting of nuclear fuel assemblies, including a plurality of adjacent housings each having a lateral wall and being able to receive a nuclear fuel assembly, the lateral walls being realised at least in part using stacking and intercrossing slotted structural assemblies (6a, 6b), each structural assembly including at least one plate (22) realised in a first material comprising aluminium. According to the invention, each structural assembly (6a, 6b) further includes a tubular cross-section element (20) inside of which is located said at least one plate (22), this tubular cross-section element (20) being realised in a second material selected from steels and titanium and alloys thereof.

Abstract: A radioactive-material container includes a container body that shields nuclear radiation, which includes a cavity that stores a basket containing a recycle fuel assembly, a lid that covers the cavity, and a metal gasket that includes a sealing area that makes a physical contact with the container body and the lid. The sealing area has a specific shape that disperses tightening stress acting on the metal gasket for a sealing.

Abstract: The object of this invention is to provide a fiber-reinforced concrete cask that ensures easy working, enables reducing working cost, excels in strength, durability and heat resistance and enables minimizing cracking; a process for fabrication of the same; and a supporting frame for molding the concrete cask. In particular, concrete cask (10) formed through injecting and solidification of concrete (11) is characterized in that sheets of reinforcement fibers having a thermal expansion coefficient equal to or lower than that of concrete (11) are provided on at least the outer circumferential surface and the inner circumferential surface of the concrete cask (10) and that the inner circumferential surface of outer sheet (21) and the outer circumferential surface of inner sheet (22) are connected with each other by strings of reinforcement fibers (23). Preferably, carbon fibers are used as the reinforcement fibers.

Abstract: A radioactive-material container includes a container body that shields nuclear radiation, which includes a cavity that stores a basket containing a recycle fuel assembly, a lid that covers the cavity, and a metal gasket that includes a sealing area that makes a physical contact with the container body and the lid. The sealing area has a specific shape that disperses tightening stress acting on the metal gasket for a sealing.

Abstract: A transport or storage cask comprises a cask body, a modular thermal conducting and shielding system and a mechanical attachment. The modular thermal conducting and shielding system includes a modular fin and a modular neutron shield. The mechanical attachment retains the modular thermal conducting and shielding system to the cask body. The modular fin is disposed between the modular neutron shield and the cask body. The modular fin is capable of dissipating thermal energy from the cask body.

Abstract: A system and method for storing high level waste. In one aspect, the invention is a system comprising: an inner shell forming a cavity for receiving high level waste, the cavity having a top and a bottom; an outer shell surrounding the inner shell so as to form a space between the inner shell and the outer shell; at least one opening in the inner shell at or near the bottom of the cavity, the at least one opening forming a passageway from the space into the cavity; a lid positioned atop the inner and outer shells, the lid having at least one inlet vent forming a passageway from an ambient atmosphere to the space and at least one outlet vent forming a passageway from the cavity to the ambient atmosphere. In another aspect, the invention is a method of using the system to store high level waste. In yet another aspect, the invention does not require the aforementioned lid but further comprises a floor plate wherein the inner and outer shells rest atop and are connected to the floor plate.

Abstract: A transfer cask for maximizing the radiation shielding for spent nuclear fuel during cask transfer procedures has a cylindrical inner shell forming a cavity within which a spent nuclear fuel canister can be placed; a cylindrical outer shell concentric with and surrounding the inner shell to form an annulus with the inner shell, the annulus adapted for receiving gamma absorbing material; a jacket shell concentric with and surrounding the second shell to form a jacket for holding a neutron absorbing liquid; the jacket shell having filling and drainage systems; and a removable bottom lid so that a canister can be lowered from the cavity into a transport cask or permanent storage cask.

Abstract: A cask includes a trunk body that includes a basket having a square pipe or a plate member forming a cell that contains a spent fuel assembly, and a neutron shield that is formed by filling a composition for neutron shielding between the trunk body and an outer cover surrounding the trunk body. The composition includes a refractory material, a density increasing agent, and a neutron shielding material composed mainly of a polymer.

Abstract: A neutron absorbing coating for use on a substrate, and which provides nuclear criticality control is described and which includes a nickel, chromium, molybdenum, and gadolinium alloy having less than about 5% boron, by weight.

Abstract: An apparatus and method are provided which are designed to structurally replace welds that attach a riser brace assembly to a jet pump riser pipe. The riser brace assembly may include an upper clamp assembly, a lower clamp assembly, and a plurality of mechanical fasteners to provide clamping forces to the upper clamp assembly and the lower clamp assembly. The upper clamp assembly and the lower clamp assembly sandwich a riser brace support, wherein the riser brace support is provided with at least one through-hole to accommodate the plurality of mechanical fasteners.

Abstract: Corner of each square pipe is molded into a terrace shape having steps. When a basket is constructed by these square pipes, steps of adjoining square pipes are assembled together face to face. Fuel rod aggregates are housed inside the square pipes and in a cells formed between the square pipes. Since the adjoining square pipes are assembled in a staggered arrangement, boundaries of the cells are defined by the walls of the square pipes itself.

Abstract: Heat conductive fins (107) are welded along both sides of a belt-like member (105a) with a margin left along edges of the both sides, thereby to form a unit (105c). The unit (105c) is welded to a body (101) with the heat conductive fins (107) from the outside of each fin. Next, another belt-like member (105b) is covered over a gap between adjacent belt-like members (105a, 105a), and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.

Abstract: A basket has a lattice-like section for accommodating individual used nuclear fuel in predetermined positions in a cask. The basket is made from aluminum composite material having good neutron absorption ability, excellent mechanical property and workability. The aluminum composite material is made by having, in an Al or Al alloy base phase, B or B compound with a neutron absorption ability and an additive element, e.g. Zr or Ti, for giving a high strength property, and subjecting to a sintering under pressure.

Abstract: In the metal billet to be used for hot dilation forming, a forward side with respect to the pressing direction has a quadrate section and its diagonal length is not more than an inner diameter of a container. Moreover, a backward side with respect to the pressing direction has a circular section and its diameter is substantially same as the inner diameter of the container. The metal billet is heated to a temperature suitable for press working and is set into a container for press forming. While a center of a workpiece of the metal billet is being bored by a boring punch to be operated by a pressing machine, the metal billet is hot-dilated so that a bottomed container for a cask is formed.

Abstract: A system and method for transferring a canister of spent nuclear fuel from a transfer cask to a receiving cask. In one aspect, the system comprises a below grade opening adapted for receiving a cask; a platform positioned within the opening, the platform capable of vertical movement; and at least two jacks for vertically moving the platform; wherein the platform is capable of lowering the cask within the opening. In another aspect, the invention is a method of transferring a canister of spent nuclear fuel to a cask comprising the steps of: lowering a receiving cask having a height into a below grade opening so that a portion of the receiving cask's height is below grade level; and transferring the canister to the receiving cask.

Abstract: A system and method for storing spent nuclear fuel below grade that affords adequate ventilation of the spent fuel storage cavity. In one aspect, the invention is a system comprising: a body having a cavity for receiving and storing a spent fuel canister, a major portion of the body positioned below grade; the body having at least one inlet ventilation duct extending from an above grade inlet to a below grade outlet in the cavity. The inlet ventilation duct can be a en elongated substantially S-shape extending from a side wall of the body to the bottom of the cavity. In another aspect, the invention is a method of storing a spent fuel canister using the system.

Abstract: A primary lid is set in a top opening of a vessel body that contains radioactive substance, and closes the top opening. The peripheral edge portion of the primary lid is welded to the inner peripheral surface of the vessel body. As the primary lid is welded, steam in the vessel body is discharged to the outside through a discharge hole in the primary lid, and a shield gas is filled into or run through a space in the outer peripheral portion of the primary lid, so as to prevent the steam from flowing into the welding portion.

Abstract: A basket assembly fixture is useful in the construction of a basket assembly for interring spent nuclear fuel rods. The basket assembly fixture has an elongate base and a pair of lifting beams disposed above the base. Lifting beam raising means are provided at both ends of the base to raise the pair of lifting beams. A transverse beam is provided below the two lifting beams and above the base. Transverse beam raising means are provided for raising the transverse beam.

Abstract: A container device (10) for storing hazardous material comprises a substantially cylindrical container block which has a central axial cylindrical through passage (13) and includes a group of storage vessels (12) for the hazardous material positioned between the central passage and the circumferential surface of the container block and which further includes a cylindrical concrete body (14) enveloping the group of storage vessels. The storage vessels (12) are positioned adjacent to one another along a closed curve, and sections of the circumferential surfaces of adjacent storage vessels (12) form the predominant part of the wall of the central passage (13). The concrete body directly contacts the storage vessels (12) over substantially all the parts of said circumferential surfaces, which do not constitute said sections. When the container device is made, the remaining parts of the circumferential surfaces of the storage vessels (12) form a permanent formwork in which the concrete body (14) is cast.

Abstract: An aluminum powder is mixed with a neutron absorber powder through cold isostatic press to form a preliminary molding. The preliminary molding is then subjected to sintering under no pressure in vacuum. After sintering, a billet is subjected to induction heating and hot extrusion to form a square pipe.

Abstract: In the cask, a shape within a cavity of a barrel main body is formed in a shape corresponding to an outer shape of a basket. The basket has a structure obtained by alternately piling up plate-like members vertically. A heat conducting plate is provided on an outer periphery of the plate-like member. Accordingly, since the basket and the cavity are in a state of being in contact state in a wide area, an efficiency of heat conduction is improved.

Abstract: The absorbing rods have a nearly the same shape as the shape of columnar control rods for PWR used in reactivity control of core in a reactor. The absorbing rods can shield neutrons, and are inserted in control rod guide pipes and measuring pipes in fuel assemblies.

Abstract: The invention is a door actuator and alignment apparatus for opening and closing the 15,000-pound horizontally sliding door of a storage overpack. The door actuator includes a ball screw mounted horizontally on a rigid frame including a pair of door panel support rails. An electrically powered ball nut moves along the ball screw. The ball nut rotating device is attached to a carriage. The carriage attachment to the sliding door is horizontally pivoting. Additional alignment features include precision cam followers attached to the rails and rail guides attached to the carriage.

Abstract: A method for grouting a decommissioned nuclear reactor containing residual water. A first, water-absorbent grout is used to grout the bottom portion of the reactor vessel. The water-absorbent grout is formed of cement and a water-absorbent particulate material, such as expanded perlite, exfoliated vermiculite or granulated bentonite. Excess water is absorbed by the particulate material, so that the residual water is incorporated in the fill material when it sets. A set retarder may be included to extend the time for uptake of residual water by the particulate material. Foam may also be included to reduce density and increase pumpability. The remaining, upper portion of the reactor vessel is grouted using lightweight cellular cement grout, lacking the water-absorbent particulate material, so that total weight of the fill remains low enough that the grouted vessel can be removed using the facility's installed crane system.

Abstract: Resin (106) for shielding neutrons is provided at the outer periphery of a shell main body (101) that shields the ?-rays. Basket (130) is constructed of a plurality of angular pipes (132) having neutron absorbing property. The inside of a cavity (102) of the shell main body (101) is processed to match its shape with the external shape of the basket (130), and the angular pipes (132) are inserted into this cavity (102) to be brought into contact with the inner surface of the cavity (102). Used nuclear fuel aggregates are accommodated and stored in latticed cells structured by the angular pipes (132). Thermal conductivity of decay heat generated from the used nuclear fuel aggregates is improved as the outer surface of the angular pipes (132) and the inner surface of the cavity (102) are in direct contact with each other.

Abstract: A device for storing heat-generating hazardous material, particularly radio-active fuel for nuclear reactors, comprises a substantially cylindrical, reinforced concrete body (11) with a cylindrical through center passage (13) and a plurality of axially elongate, substantially cylindrical storage spaces for accommodating the hazardous material which are disposed around and parallel to and radially spaced spaced from the center passage. The storage spaces are formed by sealed storage vessels (21) containing a fluid coolant and made of a heat-conducting material and being encapsulated in the concrete body (11). Heat transferred inwardly from the storage vessels (21) is carried away from the device by air or other fluid coolant flowing upwardly in the center passage (13).

Abstract: An apparatus, transfer cask, system, and method for defueling a nuclear reactor and transferring spent nuclear fuel from a spent nuclear fuel to a storage cask for long terms storage. In one aspect, the invention is an apparatus for use in transferring a canister of spent nuclear fuel from a transfer cask to a storage cask, the apparatus comprising a radiation absorbing shield surrounding a portion of a hole through which the canister can pass; means for securing the apparatus to the top surface of the storage cask; means for securing the bottom surface of the transfer cask to the apparatus; wherein the transfer cask securing means and the storage cask securing means are positioned on the apparatus so that when the apparatus is secured to both the transfer cask and the storage cask, the cavity of the transfer cask, the hole, and the cavity of the storage cask are substantially aligned; and means for moving the bottom lid in a horizontal direction once the bottom lid is unfastened from the bottom surface.

Abstract: Heat conductive fins are welded along both sides of a belt-like member with a margin left along edges of the both sides, thereby to form a unit. The unit is welded to a body with the heat conductive fins from the outside of each fin. Next, another belt-like member is covered over a gap between adjacent belt-like members, and these members are welded from the outside. With this arrangement, there is no need to weld in a narrow and long space and the entire welding step is carried out from the outside, which makes it easier to assemble a cask.

Abstract: A transport container for nuclear fuel is provided with an outer container having internal insulation, the insulation defining an internal cavity. The cavity receives a plurality of fuel containers wherein the internal volume of the fuel containers is at least 5% of the external volume of the outer container. The container allows substantially higher volume proportions of enriched fuel to be safely transported than is possible with prior containers.

Abstract: A canister is provided for storing, transporting, and/or disposing of spent nuclear fuel. The canister includes a canister shell, a top shield plug disposed within the canister, and a leak-tight closure arrangement. The closure arrangement includes a shear ring which forms a containment boundary of the canister, and which is welded to the canister shell and top shield plug. An outer seal plate, forming an outer seal, is disposed above the shear ring and is welded to the shield plug and the canister.

Abstract: A very long term storage installation for calorific products such as nuclear waste, comprises at least one closed cavity (10), in which at least one product confinement container is housed (14). To evacuate the heat released by the stored products, each container (14) is surrounded by a jacket (26) associated with a thermosiphon (24) whose cold source is formed of an air condenser provided above a slab (20) sealing the top part of the cavity. The jacket (26) is preferably interchangeable and tightly surrounds the container (14).

Abstract: A system and method for moving a canister of spent nuclear fuel from a first location, which may be within a nuclear power generation facility to a second location such as a storage cask that is used for short-term or long-term storage of spent nuclear fuel includes a first lifting mechanism for engaging a transfer cask and a second lifting mechanism for engaging and lifting the canister of spent nuclear fuel. Preferably, the method is practiced by first positioning a canister of spent nuclear fuel within the transfer cask and then engaging the transfer cask with the first lifting mechanism. The canister is engaged with the second lifting mechanism. The transfer cask having the canister positioned within is moved to the vicinity of a storage cask, and the canister is lowered from the transfer cask into the storage cask by the second lifting mechanism without disengagement of the first lifting mechanism from the transfer cask.

Abstract: A method for storing nuclear fuel in a container (10) including a concrete body and a fuel receiver embedded in the concrete body, comprises the steps of: providing formwork (62) for the concrete body and supporting the fuel receiver within the formwork; placing the formwork in an immersed position in a pool (54) containing a body of water; placing concrete in the immersed formwork (62); and removing the formwork with the concrete body cast therein from the pool (52).

Abstract: Corner of each square pipe is molded into a terrace shape having steps. When a basket is constructed by these square pipes, steps of adjoining square pipes are assembled together face to face. Fuel rod aggregates are housed inside the square pipes and in a cells formed between the square pipes. Since the adjoining square pipes are assembled in a staggered arrangement, boundaries of the cells are defined by the walls of the square pipes itself.

Abstract: A neutron absorber system for a nuclear fuel storage rack includes a neutron absorber, which is adapted to attach to a plurality of cell walls of a cell of the nuclear fuel storage rack. The neutron absorber is adapted to elastically deform to cause the attaching. A system for inserting a neutron absorber into the nuclear fuel storage rack includes means for applying at least one stress to the neutron absorber and means for releasing the at least one stress to cause the neutron absorber to attach to the plurality of cell walls of the cell of the nuclear fuel storage rack.

Abstract: A device (10) for storage of hazardous material, especially heat-producing hazardous material, such as radioactive spent nuclear reactor fuel, comprises a substantially cylindrical reinforced concrete body (12) and has an axially elongate storage space (18) for the hazardous material. A prestressed reinforcement (17) having reinforcing members (28, 29) extending helically about the storage space (18) is provided in the concrete body (12) adjacent to the outer side thereof. Preferably, the reinforcing members (28, 29) are divided into two groups, one inside the other, the hand of the reinforcing members (28) of one of the groups being opposite to the hand of the reinforcing members (29) of the other group. Also preferably, the ends of the concrete body are provided with end covers (15, 16) in which the reinforcing members (28, 29) are anchored.

Abstract: A storage/transport container for intact and broken nuclear-fuel elements has a vessel defining an interior extending along an axis and a plurality of like basket sections forming a stack extending substantially a full axial length of the interior and forming a plurality of axial full-length rectangular-section wells. Respective metal tubes extending substantially the full length of some of the wells are of complementary section to the respective wells and are each adapted to snugly hold an intact spent nuclear-fuel element. At least one box extending substantially the full length of others of the wells is of complementary section to the respective well and is adapted to hold pieces of a broken spent nuclear-fuel element.

Abstract: A universal modular container for containing, transporting, storing, or disposing of reactor pressure vessel heads (RPVHs) with attached control rod driving mechanisms has several sections that may be handled independently and thus allow easier handling of the container and packaging of the RPVHs. Various ring sections of different lengths may be used, to allow the container to have dimensions that are the best match for enclosing any particular intact reactor pressure vessel head with attached control rod driving mechanisms. The RPVH with attached CRDMs can be placed onto and attached to a bottom plate of the container, items can be removed from the reactor pressure vessel head, and then the ring sections attached to the bottom plate. The container is closed with a top plate, and the complete package is ready to be transported for storage or disposal in accordance with regulations for radioactive materials.

Abstract: A transport/storage container for heat-generating nuclear-fuel elements has spaced inner and outer side walls defining an annular space extending along an axis and having upper and lower ends. A cover is provided at the upper end and a floor at the lower end. A plurality of axially extending and angularly spaced heat-conducting metal tubes each have an inner wall section bearing in surface contact on an outer surface of the inner side wall and an outer wall section bearing in surface contact on an inner surface of the outer side wall. A concrete mass fills the space.

Abstract: An apparatus, transfer cask, system, and method for defueling a nuclear reactor and transferring spent nuclear fuel from a spent nuclear fuel to a storage cask for long terms storage. In one aspect, the invention is an apparatus for use in transferring a canister of spent nuclear fuel from a transfer cask to a storage cask, the apparatus comprising a radiation absorbing shield surrounding a portion of a hole through which the canister can pass; means for securing the apparatus to the top surface of the storage cask; means for securing the bottom surface of the transfer cask to the apparatus; wherein the transfer cask securing means and the storage cask securing means are positioned on the apparatus so that when the apparatus is secured to both the transfer cask and the storage cask, the cavity of the transfer cask, the hole, and the cavity of the storage cask are substantially aligned; and means for moving the bottom lid in a horizontal direction once the bottom lid is unfastened from the bottom surface.

Abstract: An unirradiated nuclear fuel assembly component transport system that includes a clamshell-type inner liner that opens along its axial dimension to load and unload the fuel component being transported. The exterior dimensions of the liner conform to a generic overpack tubular container. The overpack is separable into an upper and lower section with the lower section having a V-shaped channel extending along its longitudinal axis. The liner is supported in the V-shaped channel by at least one row of shock mounts on either side of the channel. The lower section of the overpack is secured from rotation and the top section is latchably engaged to the lower section of the overpack.

Abstract: Apparatus for containing nuclear fuel material within a containing environment includes an axis along which a fuel rod to be loaded is introduced, a sealing unit provided between the contaminated environment and a non-contaminated environment, the sealing unit including a first seal, a second seal and an extendible part, the first and second seals being attached to the extendible part, the sealing unit having a first state and a second state, the sealing unit having a greater extent along the axis in the second state than in the first. The first seal may be in the form of a disc having a through aperture with the second seal being a resiliently deformable seal which opens about its middle, the second seal being provided closer to the contaminated environment than the first. A method and component for loading nuclear fuel pellets into a fuel rod are also disclosed.

Abstract: A method of carrying equipment out of a nuclear reactor building that, in carrying equipment rendered radioactive out of a nuclear reactor building, makes it possible to shorten the operating time and reduce the number of casks to be used, wherein the structures of a nuclear power plant that are outside the equipment installed in the nuclear power plant are removed and these removed structures are then stored in the space in the equipment and carried out of the building.

Abstract: A neutron absorber system for a nuclear fuel storage rack includes a neutron absorber, which is adapted to attach to a plurality of cell walls of a cell of the nuclear fuel storage rack. The neutron absorber is adapted to elastically deform to cause the attaching. A system for inserting a neutron absorber into the nuclear fuel storage rack includes means for applying at least one stress to the neutron absorber and means for releasing the at least one stress to cause the neutron absorber to attach to the plurality of cell walls of the cell of the nuclear fuel storage rack.

Abstract: The invention relates to a method of measuring the tritium activity of a drum (1) of radioactive waste containing a quantity of radioactive waste (2) and a free volume, the method consisting of measuring the quantity of 3He produced by the decay of the tritium contained in said radioactive waste during a defined period of time and deducing from it the corresponding activity of the tritium contained in said radioactive waste (2).

Abstract: A canister containing spent fuel assemblies is contained in a body of a transportation cask. A top opening of a vessel body of the canister is closed by a lid welded to the vessel body. A ring-shaped elastic tube is provided between the inner surface of the upper end portion of the body and the outer surface of the upper end portion of the vessel body. The tube seals the gap between these surfaces to prevent a fluid from getting into the gap between the surfaces through the top opening of the body. An inspection space for the insertion of a tester for detecting the welding state of the lid is defined between the inner surface of the upper end portion of the body and the outer surface of the upper end portion of the vessel body.

Abstract: A lifting lug for a nuclear-waste container has a tubular body having an inner end formed with a flange adapted to be bolted to the container and a transverse wall set in and tightly fitted to a smaller-diameter outer end of the tubular body. The wall is a separate piece from the body and is press-fitted to the tubular body. The wall is mounted at a load point of the lifting lug. In addition the wall is formed of a disk and/or a ring, typically as one unitary piece with the disk and ring spaced from each other.

Abstract: A packaging device, for bulk transport of uraniferous fissile materials.

Abstract: An apparatus, system, and method of storing and transferring a canister of spent nuclear fuel. In one aspect, the apparatus is a lid for a ventilated vertical overpack having a chamber for receiving spent nuclear fuel, the lid having ventilation ducts. In one aspect, the system comprises: a lid for a ventilated vertical overpack having a chamber for receiving spent nuclear fuel, the lid having ventilation ducts; and a ventilated vertical overpack having a cylindrical body including lower ventilation ducts, a bottom, and a chamber formed by the body and the bottom adapted for receiving a canister of spent nuclear fuel.