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 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.

A system and method for performing active scanning on a nuclear fuel rod are provided. The system includes an electrically-driven neutron generator including an ion source, an accelerator, and a target; a moderator surrounding the neutron generator and configured to moderate neutrons generated by the neutron generator; a fuel rod channel disposed within the moderator, the fuel rod channel configured to receive a nuclear fuel rod and subject the nuclear fuel rod to a predetermined neutron flux; and a plurality of radiation detectors. When the nuclear fuel rod is subjected to the predetermined neutron flux, neutrons induce a secondary radiation of prompt and delayed gamma emissions, neutron emission, or a combination thereof that are detected by the plurality of radiation detectors to determine an amount of fissile material in the nuclear fuel rod and a spatial distribution of the fissile material along a length of the nuclear fuel rod.

A shipping container comprises a tubular or cylindrical shell having a closed end and an open end, a top end-cap removably secured to the open end of the tubular or cylindrical shell, and at least one fuel assembly compartment defined inside the shell. Each fuel assembly compartment includes elastomeric sidewalls and is sized and shaped to receive an unirradiated nuclear fuel assembly through the open end of the shell. The shipping container may further include a divider component, for example having a cross-shaped cross-section with ends of the cross secured to inner walls of the shell, and the divider component and the inner walls of the shell define the fuel assembly compartments. To load, the shipping container is arranged vertically and an unirradiated nuclear fuel assembly is loaded through the open end of the shell into each compartment, after which the open end is closed off by securing the top end-cap.

A system and method for removing spent fuel assemblies from a fuel building and transporting them to on-site facilities. A cask transporter is moved into the fuel building with an empty spent fuel storage cask, spent fuel assemblies are loaded into spent fuel storage cask, the cask is sealed, and the cask transporter moves the loaded spent fuel storage cask to a handling area for final disposal. Components of the system include a penetration cover, a lifting mechanism, a control system, a valve system, and the cask transporter.

A system and method for removing spent fuel assemblies from a fuel building and transporting them to on-site facilities. A cask transporter is moved into the fuel building with an empty spent fuel storage cask, spent fuel assemblies are loaded into spent fuel storage cask, the cask is sealed, and the cask transporter moves the loaded spent fuel storage cask to a handling area for final disposal. Components of the system include a penetration cover, a lifting mechanism, a control system, a valve system, and the cask transporter.

Illustrative embodiments provide methods and systems for migrating fuel assemblies in a nuclear fission reactor, methods of operating a nuclear fission traveling wave reactor, methods of controlling a nuclear fission traveling wave reactor, systems for controlling a nuclear fission traveling wave reactor, computer software program products for controlling a nuclear fission traveling wave reactor, and nuclear fission traveling wave reactors with systems for migrating fuel assemblies.

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.