A method for restraining a sleeve lining a tube passing through a nuclear reactor pressure vessel is provided. The method includes attaching in situ a radial protrusion on an external surface of the sleeve; and attaching a collar to an end of the tube and coupling the radial protrusion with the collar to retain the thermal sleeve in position.

Clamp systems include multiple, separate clamps joinable to components subject to relative rotation. Clamps may have similarly-positioned features to simplify installation and/or removal about a small area for all clamps in the system. Each clamp cannot freely rotate relative to an adjacent clamp but does not pass vertical loads to an adjacent clamp. Clamps may use mating shapes like an extension and recess to limit rotation. Clamps fit to the perimeters of components to which they individually secure by biasing against the components. At least one clamp has a transitional surface to provide space between the clamp and component to provide containment to a weld or other joining structure. Clamp systems can be tightened by included fasteners. Crimp nuts or other locking structures can preserve the biased and secured nature of the clamps and underlying structures. Clamp systems may be used to secure or repair a lifting rod assembly.

A reactor pressure vessel includes a reactor pressure vessel body, a nozzle structure connected to the reactor pressure vessel body, a conduit structure connected to the nozzle structure, and a restraint device attached around a portion of the conduit structure. The restraint device includes collar parts that have cross sections corresponding to respective segments of a periphery of the portion of the conduit structure, brackets attached to the nozzle structure, and rods connecting the brackets to the collar parts. The collar parts are connected end-to-end to each other such that a cross section of the collar parts connected to each other corresponds to the periphery of the portion of the conduit structure. The collar parts are pinned to each other. The brackets spaced apart from each other around a periphery of the nozzle structure.

A jet pump slip joint repair assembly includes at least one clamp and a bushing configured to be inserted in a bore of a diffuser and to surround a portion of an inlet mixer. The clamp includes a gripping surface and a gripping collar. The bushing includes a generally cylindrical sidewall, the sidewall configured to surround the portion of the inlet mixer, a grooved flange on an upper surface of the sidewall, at least one cutout between adjacent portions of the grooved flange, and a groove on an inner, bottom surface of the sidewall. The assembly also includes a seal in the groove. The seal is flexible and formed of a metallic material. The seal is configured to be compressed when the at least one clamp engages the bushing.

A replacement thermal sleeve with a flange for a reactor vessel closure head penetration adapter housing. By altering a diameter of the flange, a replacement thermal sleeve can be installed through the narrow diameter of the penetration adapter housing opening from under the reactor vessel head. The flange can be compressible or expandable or the tubular wall of the thermal sleeve can be inserted in longitudinal sections, one at a time, into an opening in the underside of the penetration head adapter and reformed within the opening when fully inserted.

A method for peening an obstructed region of a metal assembly that is obstructed by an obstructing part of the metal assembly is provided. The method includes determining an optimal peening path for treating the obstructed region irrespective of the obstructing part; identifying a portion of the obstructing part within the optimal peening path; determining a section of the portion of the obstructing part that is removable without affecting a mechanical integrity and functionality of the obstructing part; removing, by machining, the section so as to create additional space along the optimal peening path; and peening the obstructed region, a path of the peening at least partially crossing through the additional space. A method for peening a nuclear reactor pressure vessel is also provided.

A replacement thermal sleeve with a flange for a reactor vessel closure head penetration adapter housing. By altering a diameter of the flange, a replacement thermal sleeve can be installed through the narrow diameter of the penetration adapter housing opening from under the reactor vessel head. The flange can be compressible or expandable or the tubular wall of the thermal sleeve can be inserted in longitudinal sections, one at a time, into an opening in the underside of the penetration head adapter and reformed within the opening when fully inserted.

Disclosed herein is an articulated manipulator capable of moving a tool such as an inspection device, a processing device, or a welding device to a desired position for inspection or repair of a defect portion in a limited place. The articulated manipulator includes a base plate, a movable unit slidably coupled on the base plate, a rotatable unit rotatably coupled on the movable unit, and a rotation unit rotatably coupled to one side of the rotatable unit.

Fuel assembly for a nuclear reactor comprising a housing of longitudinal axis (X) having a central section containing nuclear-fuel pins and an upper section, forming a portion of the head of the assembly, containing a upper neutron shielding device (NSD) including neutron absorbers and means for reversibly interlocking with the housing and a moveable weight forming the head of the NSD, which is mounted so as to be able to move translationally relative to the rest of the NSD over a given path, said interlocking means being configured so that the NSD and the housing can be interlocked and uninterlocked by moving the moveable weight along the longitudinal axis by means of a grapple for extraction of the NSD, the claws of this grapple engaging with the moveable weight and the rest of the NSD being in downward longitudinal abutment in the interior of the housing.

A control rod drive replacement device is provided. The control rod drive replacement device includes a first channel for mounting on a support under a nuclear reactor pressure vessel; a first control rod drive extractor removably received in the first channel, the first control rod drive extractor including a first housing configured for receiving a first control rod drive, the first housing being movable between a horizontal orientation in which the first housing is aligned within the first channel and a vertical orientation in which the first housing is aligned for receiving the first control rod drive from the nuclear reactor pressure vessel; a second channel connected on top of the first channel under the nuclear reactor pressure vessel; and a second control rod drive extractor removably received in the second channel, the second control rod drive extractor including a second housing configured for receiving a second control rod drive, the second housing being movable between a horizontal orientation in which the second housing is aligned within the second channel and a vertical orientation in which the second housing is aligned for receiving the second control rod drive from the nuclear reactor pressure vessel.