Abstract: Sealing means comprising a seal carrier and a seal connected thereto, wherein the seal carrier is removably fixable between two areas insulated from each other, and a transfer device between two chambers, which are separated by a wall, wherein said transfer device comprises a transfer mechanism and at least one sealing means according to the invention which is positioned between the wall and the transfer mechanism.

Abstract: A method enables dismantling of a control element of a boiling water reactor. Two control element leaves that are disposed opposite one another are separated by means of a roll-cutting method from the other two control element leaves, respectively along an intersection line extending in the longitudinal direction thereof and in the vicinity of the longitudinal center axis.

Abstract: The core of a pressurized water reactor is assembled in such a way that if the fuel elements on the edge of the core are bent, these fuel elements are oriented such that the bending of the fuel elements points outwards in a convex manner. When the reactor is in operation, forces arise which increase the size of small gaps between the fuel elements at the expense of greater gaps and counteract the bending effect of the fuel elements.

Abstract: A method is provided for removing radioactive internals structural members in the core of a reactor pressure vessel in a containment vessel. The method includes placing a first cask in a first internals assembly, detaching radioactive first internals structural members from second internals structural members in the first internals assembly, placing the detached first internals structural members in the first cask, placing the first internals assembly in a second cask, and removing the second cask containing the first internals assembly and containing the casked detached radioactive first internals members from the containment vessel. The first internal members may be radioactive baffle plates, and the second internals members may be former plates bolted to the radioactive baffle plates. Novel tooling, framework and fixtures facilitate disassembling, moving and storing the radioactive baffle plates.

Abstract: A pressurizer is for a pressurized water nuclear power plant and it includes an upper cap provided with a tube; an end piece connected to the tube using a weld; and a sleeve protecting the weld, disposed inside the tube. The protective sleeve is mounted in a removable manner, such that the thermal sleeve is removed.

Abstract: A servicing platform for a nuclear reactor refueling floor is provided. In various embodiments, the servicing platform includes a base structured to be anchored to a refueling floor of the nuclear reactor. The servicing platform additionally includes a telescoping mast having a mounting collar at a first end that is rotationally attached to the base, and a personnel work basket pivotally coupled to a second end of the mast.

Abstract: An apparatus and method for manufacturing a handling pole including a pole section, a pole adapter connected to one end of the pole section, a spade member connected to the other end of the pole section, and a nut assembly for connecting adjoining poles. The pole adapter may include an upper sleeve and the spade member may include a lower sleeve.

Abstract: The invention relates to a device for connecting the upper (21) and lower (23) guide ducts for guiding a thermocouple for the upper internals of a nuclear reactor. The device comprises a plug (41) fastened to the lower duct (23), comprising, on the one hand, a bore (43) for accommodating an end-piece (24) on the end of the upper duct (21) and, on the other hand, locking means (45) for locking it in a housing of a sleeve (32) of a tap (30), retaining means (48, 49) for keeping the plug (41) in the locked position in the sleeve (32), and means for blocking the plug (41) and for aligning the lower duct (23) and the upper duct (21) in said sleeve (32) of the tap (30).

Abstract: A jet pump is provided with a riser as a coolant supply tube, an inlet mixer forming a turn-around path for the coolant, a diffuser and a jet pump beam provided with a bolt fixing device. The bolt fixing device includes: a head bolt of a jet pump beam for pushing and supporting the inlet mixer from an upper side of the riser, the head bolt being provided with a polygonal head portion; a lock cap provided on the polygonal head portion of the head bolt to be slidable in an axial direction thereof and integrally rotatable; a body housing disposed on an upper surface of the jet pump beam and adapted to accommodate the lock pin; a plurality of tapered external teeth formed on an outer peripheral side surface of the lock cap; and a plurality of internal tooth-shaped grooves formed to the body housing so as to be selectively engaged with the external teeth of the lock cap so as to fix the head bolt of the jet pump beam.

Abstract: Welding repairs are performed in an underwater environment adjacent the bottom head of the nuclear reactor vessel. To provide a dry welding environment, segments of a lower caisson are passed through the core plate holes and assembled along the interior surface of the bottom head. The assembled segments are held down by brackets and sealed to one another and to the bottom head by a water curable polymer. An upper caisson is passed through the core plate hole to sealingly engage the lower caisson. The caissons are pumped dry and welding equipment is passed through the caissons to effect weld repairs about the stub tube or along the bottom head cladding.

Abstract: A method for carrying out a reactor internal, comprising steps of: forming a first opening portion in a ceiling of a reactor building at a position directly above an equipment pool in said reactor building; cutting a cylindrical reactor internal surrounding a core in a reactor pressure vessel disposed in said reactor building, at one position in an axial direction; surrounding said cut cylindrical reactor internal with a radiation shield; and carrying out said cylindrical reactor internal surrounded by said radiation shield out of said reactor building through said first opening portion.

Abstract: A method is provided for removing radioactive internals structural members in the core of a reactor pressure vessel in a containment vessel. The method includes placing a first cask in a first internals assembly, detaching radioactive first internals structural members from second internals structural members of the first internals assembly, placing the detached first internals structural members in the first cask, placing the first internals assembly in a second cask, and removing the second cask containing the first internals assembly and containing the casked detached radioactive first internals members from the containment vessel. The first internal members may be radioactive baffle plates, and the second internals members may be former plates bolted to the radioactive baffle plates. Novel tooling, framework and fixtures facilitate disassembling, moving and storing the radioactive baffle plates.

Abstract: Example embodiment damping devices may include a housing capturing a piston. The housing may be filled and/or able to be filled with a damping fluid compatible with the nuclear reactor coolant, so that a leak from the housing or coolant passing into the housing does not damage the reactor or example embodiment devices. Example embodiments may further include one or more springs that provide an elastic force opposing movement between the piston and housing. A shaft of the piston and an end of the housing may be connected to two nuclear reactor components with relative motion or vibration to be damped. Example methods may use example embodiment damping devices to reduce and/or prevent relative motion and vibration among components of a nuclear reactor.

Abstract: A method of fuel bundle consideration in a reactor. The method includes creating or editing bundle groups including fuel bundles.

Abstract: A method of fuel bundle consideration in a reactor. The method includes creating or editing bundle groups including fuel bundles.

Abstract: A U-framed structure that spans a reactor vessel of a pressurized water reactor power plant and rides on wheels that fit on the rails of the nuclear plant's refueling machine. A curved monorail is supported on the underside of the U-frame structure and guides a trolley system which travels on the monorail. The trolley system supports a hoist which is used for lifting, positioning and lowering reactor service equipment on the floor of the power plant's refueling canal.

Abstract: A method to insert nuclear fuel pellets into a fuel rod cladding tube, having the steps of providing a cladding tube, providing at least one nuclear fuel pellet to be incorporated into the cladding tube, measuring a length of the at least one nuclear fuel pellet with a camera, comparing the length of the at least one nuclear fuel pellet to an expected length, and incorporating the at least one nuclear fuel pellet into the cladding tube when the compared length of the at least one nuclear fuel pellet is within a threshold value of the expected length.

Abstract: A two-part integrated head assembly (100) is disclosed wherein the lower portion (110) attaches to, and is supported by, the reactor vessel closure head (90), and the upper portion (160) is fluidly connected to the lower portion, but is supported externally from the reactor vessel closure head. In the disclosed embodiment, the upper portion includes transverse support beams (170) that engage containment walls (92), for example steam generator walls, to support the upper portion. A duct (150) releasably connects a fan plenum (165) in the upper portion with an annular plenum in the lower portion, such that fans (166) can draw heated air from around the CEDMs (95). In one embodiment, a chiller (168) is provided in the fan plenum to cool the air prior to expelling it in containment. A missile shield (169) is also provided in the upper portion.

Abstract: A method and device to repair nuclear fuel assembly structural defects in the top nozzle to guide thimble connection, wherein the device includes a repair sleeve comprising tendons configured to deflect to allow establishment of a structural connection between a projection on each tendon and a dimple area of a guide thimble.

Abstract: A maintenance/repair device for reactor internal structure 6 of the present invention includes a device body 6a configured to be fixed on a reactor internal structure 49. Connected to the device body 6a is a welding-part repair mechanism 6b configured to repair a welding part 49a of the reactor internal structure 49. Thus, a welding part 2a of the reactor internal structure 49 can be repaired by the welding-part repair mechanism 6b, while the device body 6a is fixed on the reactor internal structure 49.

Abstract: A method to load a nuclear fuel rod, comprising, providing nuclear fuel pellets in a fuel plate transfer unit; transferring the nuclear fuel pellets from the fuel plate transfer unit to a fuel pellet column through the use of a belt, indexing the nuclear fuel pellets in the fuel pellet column to a nuclear fuel pellet loading machine; and pushing the fuel pellet column into a fuel rod cladding.

Abstract: A joint tong apparatus for a radiation shielding facility. A spherical ball has a through-hole. An inner spherical socket and an outer spherical socket are installed in a hole formed in a partition between a radiation-shielded room and a control room so as to enclose the spherical ball on inner and outer sides. A bar is inserted and coupled into and to the through-hole of the spherical ball. An inner joint assembly has a first housing coupled to a shielded room-side end of the bar and a first pivot member pivotably mounted on a free end of the first housing. An outer joint assembly having a second housing coupled to a control room-side end of the bar and a second pivot member pivotably mounted on a free end of the second housing. The apparatus further includes a tong assembly, a handle assembly, a tong manipulation cable, and a pair of pivot manipulation cables.

Abstract: An annular facing is machined in an inside surface of the spherical wall around the periphery of a zone where the wall has a bore for securing the tube passing therethrough. A first welding material is deposited in the facing, and the bore is made by drilling through a portion of the spherical wall that is surrounded by the facing. The tube is engaged tightly in the bore, and a second welding material is deposited in the facing at the periphery of the tube in order to weld the tube to the first welding material. At least one of the operations of depositing the first and second welding materials in the facing is performed automatically by causing a welding torch to turn around the axis of the bore while moving the torch in a direction that is parallel to the axis of the bore and while causing it to pivot about an axis that is orthogonal to the axis of the bore while rotation is taking place.

Abstract: An apparatus for delivering a tool into a nuclear reactor jet pump submerged in a reactor pool includes a frame, and a propulsion unit for controlling the movement of the tool delivery apparatus within a pool of liquid. A guide assembly provides for delivery and insertion of the tool into an inlet of the jet pump and includes a bore insertion portion. A tool position driver provides for controlling the vertical position of the tool in relation to the guide assembly.

Abstract: A method of preventing separation of a feedwater sparger end bracket assembly comprises installing first and second clamp members of a clamp over a feedwater sparger end bracket assembly in opposition to one another, and leaving the clamp in place to constrain the feedwater sparger end bracket assembly against separation in first, second and third directions.

Abstract: A system for exchanging a control rod drive of a nuclear reactor is provided. The system may include an integrated drive exchange assembly system (IDEAS). The IDEAS may include a trunnion cart attached to a tower assembly. The tower assembly may include an integrated extension carriage assembly. The IDEAS may also include a control rod drive adapter; and a lead cart connected to the trunnion cart assembly.

Abstract: The apparatus for creating and editing a nuclear reactor core template includes a graphical user interface and a processor controlling the graphical user interface to display a graphical representation of a nuclear reactor core. Via the graphical user interface, the processor provides a user with graphical tools for at least one of assigning fuel bundle categories to fuel bundle positions in the graphical representation and editing assigned fuel bundle categories to the fuel bundle positions in the graphical representation.

Abstract: An apparatus for inspecting a nuclear reactor may include a track, arm, fixing device, and effector. The arm may be operatively connected to the track, the fixing device may be operatively connected to the track, and the effector may be operatively connected to the arm. The arm may have contracted and expanded lengths. The expanded length may be greater than two times the contracted length. The track may include one or more motors adapted to move the arm relative to the track. A method of inspecting, performing maintenance on, or repairing a reactor may include: operatively connecting a fixing device, track, arm, and effector to form an apparatus; inserting the apparatus into the reactor; fixing the apparatus within the reactor; and operating the apparatus. A method of operating a reactor may include shutting down; inspecting, performing maintenance on, or repairing the reactor; and starting up the reactor.

Abstract: Marking of the cuts which have to be made, cutting of the section at two ends, removal of the section which has to be replaced, bevelling of the joint ends of the parts remaining after the section has been cut out from the pipe, adjustment of a new or replacement section for length and bevelling of its joining ends and positioning and narrow bevel welding of the ends joining the replacement section to the ends of the remaining parts of the pipe are performed outside the pipe. Within the pipe operations of machining and inspecting an internal part of the joining ends welded together are performed by remote control in a programmed way by introducing and positioning means for working within the pipe from a component of the primary circuit.

Abstract: Illustrative embodiments provide modular nuclear fission deflagration wave reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, modular nuclear fission deflagration wave reactors, modular nuclear fission deflagration wave reactor modules, methods of operating a modular nuclear fission deflagration wave reactor, and the like.

Abstract: A method of fuel bundle consideration in a reactor. The method includes creating or editing bundle groups including fuel bundles.

Abstract: A vertical spring wedge restores a tight fitup against an adjacent structure, such as between an inlet mixer and an adjacent restrainer bracket in a boiling water nuclear reactor jet pump. The vertical spring wedge includes a U-shaped bracket including a pair of guiding portions and a pair of bracket holes. A pair of wedge assemblies are coupled with the bracket, each of the wedge assemblies including a wedge segment attached to a spring-loaded guide rod. The guide rods are displaceable in the bracket holes between a retracted position and an extended position. The wedge segments engage the guiding portions, and a combination of the bracket and wedge assemblies have a first width when the guide rods are in the retracted position and have a second width wider than the first width when the guide rods are in the extended position.

Abstract: The invention relates to a method and a device for loading a fuel assembly into the core of a nuclear reactor. The inventive method consists in: inserting a dummy assembly (4) into the loading location (3) of the fuel assembly (5), said dummy assembly essentially having the same shape and dimensions as the loading location (3) and comprising smooth side walls; fixing the position of at least one fuel assembly (5) that is adjacent to the loading location (3), in the presence of the aforementioned dummy assembly (4), in relation to at least one second assembly (5) of the core, using at least one fuel assembly support tool (11); removing the dummy assembly (4) from the loading location (3); introducing the fuel assembly (5) which is being loaded into the loading location (3); and removing the fuel assembly support tool(s) (11).

Abstract: A nuclear power plant and method of operation for augmenting a second reactor thermal power output in a second operation cycle to a level larger than a first reactor thermal power output in the previous operation cycle. The plant is equipped, for example, with a reactor; a steam loop comprising high and low pressure turbines; a condenser for condensing steam discharged therefrom the low pressure turbine; a feedwater heater for heating feedwater supplied from the condenser; and a feedwater loop for leading feedwater discharged from the feedwater heater to the reactor. The operation method includes decreasing a ratio of extraction steam which is led to the feedwater heater from a steam loop in the second operation cycle.

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 device for handling a guide tube assembly. The assembly has an upper tube and a lower tube in each of which there are fixed horizontal guide plates arranged such that they are spaced apart in an axial direction. The handling device itself includes a gripper having a tubular body and two opposing arms located at one end of the tubular body and moveable between a retracted position and a deployed position, the arms bearing against a lower surface of a contacted guide plate when in the deployed position. A control member is located at an opposite end of the tubular body for controlling the arms. The length of the tubular body of the gripper selected to be: a) greater than the distance between an upper end of the upper tube and a first guide plate of the lower tube; and b) less than the distance between the upper end of the upper tube and a third guide plate of the second tube.

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: A method for optimizing a nuclear reactor refueling outage schedule using a computer system coupled to a database is provided. The method includes, in one embodiment, inputting into the computer system data relating to a current status of a nuclear reactor, with the reactor data including information related to current tooling, processes, and financial data; storing the reactor data in the database; and inputting into the computer system a proposed refueling outage schedule profile, with the outage schedule profile including critical path tasks and an estimated duration for each of the critical path tasks. The method further includes generating a gap analysis by comparing the proposed refueling outage schedule profile to a predetermined refueling outage schedule profile, where the predetermined schedule profile represents an optimum schedule; and determining the critical path tasks where adjustments to the task durations result in an optimized refueling outage schedule profile using the gap analysis.

Abstract: A device and method to move a fuel assembly of a nuclear reactor, wherein the device eliminates the potential for dropping the fuel assembly due to stress corrosion cracking of the upper guide thimble sleeves that attach the top nozzle to guide thimbles.

Abstract: In a method for sealing a hollow, elongate member within a reactor pressure vessel of a nuclear reactor, a section of the elongate member may be removed to separate the elongate member into an upper portion and a lower portion with an opening there between. The lower portion may be attached to a surface of the reactor pressure vessel in-situ, so as to seal off a potential leakage path through the elongate member.

Abstract: A data management system stores and visualizes data generated during process management. The data management system provides different data management services and definitions of these are stored in a database. Management of data in this database is carried out by a collection of software agents, one of which, the management information agent, can access, update and download data in or from the database. Stored separately are graphical user interfaces which are downloaded to a user in accordance with the relevant service definition stored in the database when the user requests a particular data access service.

Abstract: In a nuclear reactor, cooled by pressurized water, an apparatus is employed for replacing a section of a primary circuit primary pipe that interconnects first and second components of a primary circuit. The apparatus cuts out and removes a section of the primary pipe. Supports are provided for the end parts of a new replacement section in a position held by the removed pipe. The apparatus bevel welds the end parts of the new replacement section of the primary pipe to confronting corresponding ends of the remaining primary pipe. Means are provided to work within the pipe along the entire length of the interior surface of the primary pipe and is introduced through one of first and second components of the primary circuit to a location within the welded replacement pipe section.

Abstract: A method of servicing a nuclear reactor during a reactor outage is provided. The reactor includes a primary containment vessel and a reactor pressure vessel positioned in the primary containment vessel. The method includes positioning a servicing platform above the reactor pressure vessel and performing predetermined servicing operations on the reactor. The servicing platform includes a frame having a plurality of interconnected beams, a support structure attached to the frame, and a floor attached to a top of the frame. The floor includes a reactor access opening sized to permit access to the reactor pressure vessel. The servicing platform also includes at least one auxiliary platform movably coupled to the frame and extending into the access opening. The at least one auxiliary platform is movable along a perimeter of the access opening of the floor.

Abstract: Marking of the cuts which have to be made, cutting of the section at two ends, removal of the section which has to be replaced, bevelling of the joint ends of the parts remaining after the section has been cut out from the pipe, adjustment of a new or replacement section for length and bevelling of its joining ends and positioning and narrow bevel welding of the ends joining the replacement section to the ends of the remaining parts of the pipe are performed outside the pipe. Within the pipe operations of machining and inspecting an internal part of the joining ends welded together are performed by remote control in a programmed way by introducing and positioning means for working within the pipe from a component of the primary circuit.

Abstract: An integrated head assembly (100) is disclosed for a nuclear reactor. The preferred integrated head assembly includes a lift assembly (150) that supports the reactor vessel closure head (90) and integrated head assembly for removal, a separate support structure (202) supported by a ring beam (151) that sets atop the reactor vessel closure head, a shroud assembly (200), a seismic support system (300), a baffle assembly (500), a missile shield (400), and a CRDM cooling system. The CRDM cooling system draws cooling air into the baffle assembly, downwardly past the CRDMs (96), outwardly to upright air ducts (600), upwardly to an upper plenum (680), and out of the assembly through the air fans (190). In a second embodiment the integrated head assembly (1100) includes a missile shield (1400) and CRDM cooling system (1600) that permits access to individual CRDMs from above.

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 lifting support for a boiling water reactor nuclear fuel assembly comprising a grappling head configured to allow attachment to a lifting device, a body with an upper end and a lower end, the upper end connected to the grappling head, the body configured to be inserted into a water channel of a boiling water reactor nuclear fuel assembly, and an end connected to the lower end, the end configured to be accepted by the nuclear fuel assembly.

Abstract: A method is provided for determining and controlling feed water level in a steam generator of a nuclear power plant, whereby the water level sensor is calibrated in terms of the pressure drop across structural components in the feed water path. The water level differential pressure sensor is calibrated so that maximum water level is indicated as the level corresponding to the upper tap level plus the pressure drop across the foregoing structural components at maximum power plant power.

Abstract: A seal plate for repairing damaged areas in a pressure vessel cladding includes a first side and an opposing second side and a sealing portion located on the second side, with the sealing portion circumscribing the seal plate. The seal plate also includes a seal lip extending from a periphery of the sealing portion and a cavity located in the second side, with the cavity circumscribed by the sealing portion. The seal plate further includes at least one purge port extending from the first side to the cavity. Each purge port is in fluid communication with the cavity.

Abstract: The disclosed invention is a system and a method utilizing a web-based interactive database to automate the process for managing internal components of a plant. The system captures all essential information and provides on-line up-to-date information upon request. The system provides valuable information to a customer to analyze the plant specific problem and offers inspection methods, mitigation methods and processes to resolve the problem.