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.

The present invention relates generally to electric power and process heat generation using a modular, compact, transportable, hardened nuclear generator rapidly deployable and retrievable, comprising power conversion and electric generation equipment fully integrated within a single pressure vessel housing a nuclear core. The resulting transportable nuclear generator does not require costly site-preparation, and can be transported fully operational. The transportable nuclear generator requires an emergency evacuation area substantially reduced with respect to other nuclear generators as it may be configured for operation with a melt-proof conductive ceramic core which allows decay heat removal even under total loss of coolant scenarios.

The present invention relates generally to electric power and process heat generation using a modular, compact, transportable, hardened nuclear generator rapidly deployable and retrievable, comprising power conversion and electric generation equipment fully integrated within a single pressure vessel housing a nuclear core. The resulting transportable nuclear generator does not require costly site-preparation, and can be transported fully operational. The transportable nuclear generator requires an emergency evacuation area substantially reduced with respect to other nuclear generators as it may be configured for operation with a melt-proof conductive ceramic core which allows decay heat removal even under total loss of coolant scenarios.

Fuel bundles for a nuclear reactor are described and illustrated, and in some cases include fuel elements each having a fissile content of .sup.235U between about 0.9 wt % .sup.235U and 5.0 wt % .sup.235U, and wherein at least one of the fuel elements is a poisoned low-enriched uranium fuel element including a neutron poison in a concentration greater than about 5.0 vol %.

A sealing device is provided to form a sealed region about one or more surfaces to be treated. The sealing device has an open end with a rim configured to matingly engage a treatment surface. The sealing device is braced both vertically and laterally, and the sealed region is flooded and pressurized. A peening nozzle and manipulating tooling are positioned within an interior volume of the sealing device. Pressurized fluid is ejected from the nozzle causing the formation of cavitation bubbles. The nozzle flow causes the cavitation bubbles to settle on the surfaces to be treated. The collapsing impact of the cavitation bubbles imparts compressive stress in the materials of the treatment surfaces.

A sealing device is provided to form a sealed region about one or more surfaces to be treated. The sealing device has an open end with a rim configured to matingly engage a treatment surface. The sealing device is braced both vertically and laterally, and the sealed region is flooded and pressurized. A peening nozzle and manipulating tooling are positioned within an interior volume of the sealing device. Pressurized fluid is ejected from the nozzle causing the formation of cavitation bubbles. The nozzle flow causes the cavitation bubbles to settle on the surfaces to be treated. The collapsing impact of the cavitation bubbles imparts compressive stress in the materials of the treatment surfaces.

A sealing member is provided to create a sealed region about an annulus formed between an inner body, such as a thermal sleeve, and an outer body, such as a control rod drive housing nozzle. Liquid is introduced into the sealed region to create a flooded region, which is pressurized to a desired level. A nozzle is provided into the flooded region, the nozzle being configured to fit within the annulus. Pressurized fluid is ejected from the nozzle, causing the formation of cavitation bubbles. The nozzle flow causes the cavitation bubbles to settle on the surfaces forming the annulus. The collapsing impact of the cavitation bubbles imparts compressive stress in the materials of the surfaces forming the annulus.

A sealing member is provided to create a sealed region about an annulus formed between an inner body, such as a thermal sleeve, and an outer body, such as a control rod drive housing nozzle. Liquid is introduced into the sealed region to create a flooded region, which is pressurized to a desired level. A nozzle is provided into the flooded region, the nozzle being configured to fit within the annulus. Pressurized fluid is ejected from the nozzle, causing the formation of cavitation bubbles. The nozzle flow causes the cavitation bubbles to settle on the surfaces forming the annulus. The collapsing impact of the cavitation bubbles imparts compressive stress in the materials of the surfaces forming the annulus.

Systems and methods of transferring nuclear fuel from fuel pools having size and/or weight limitations to a storage or transport cask are disclosed. A canister containing spent nuclear fuel is inserted into a transfer cask. A shielding sleeve is then placed around the transfer cask. A lifting device simultaneously lifts the transfer cask and the shielding sleeve over a storage cask and the spent fuel is transferred from the transfer cask to the storage or transport cask.

A system and method for managing spent nuclear fuel includes a small capacity canister that preferably encloses or encapsulates a single spent nuclear fuel rod assembly but can enclose up to six spent nuclear fuel rod assemblies. The canister is air tight and prevents radioactive material from escaping. The canister is loaded by positioning a single spent nuclear fuel rod assembly in the canister and then closing the canister to make it air tight.