A system for servicing a nuclear reactor module comprises a crane operable to attach to the nuclear reactor module, wherein the crane includes provisions for routing signals from one or more sensors of the nuclear reactor module to one or more sensor receivers.

Control rod drives include linearly-moveable control elements inside an isolation barrier. Control rod drives move the control element through secured magnetic elements subject to magnetic fields. Induction coils may generate the magnetic fields across a full stroke length of the control element in the reactor. A closed coolant loop may cool the induction coils, which may be in a vacuum outside the isolation barrier. A control rod assembly may house the magnetic elements and directly, removably join to the control element. The control rod assembly may lock with magnetic overtravel latches inside the isolation barrier to maintain an overtravel position. Overtravel release coils outside the isolation barrier may release the latches to leave the overtravel position. Methods of operation include selectively energizing or de-energizing induction coils to drive the control element to desired insertion points, including full insertion by gravity following de-energization. No direct connection may penetrate the isolation barrier.

An electrodeposition system, for additive manufacturing of a three-dimensional structure, includes at least one electrochemical cell. The at least one electrochemical cell includes a receptacle containing an electrolytic bath. At least one nozzle opens from the receptacle toward and proximate a substrate, which is configured as a working electrode of the at least one electrochemical cell. The at least one electrochemical cell also includes a counter electrode disposed in the electrolytic bath. In a method for forming a three-dimensional structure, a metal salt, dissolved in the electrolytic salt, flows through the nozzle to deposit a metal of the metal salt on a surface of the substrate configured as the working electrode. The system may be configured for relative movement between the at least one nozzle and the substrate, enabling additive manufacturing of a three-dimensional structure by electrodeposition.

System for detecting, in a space being monitored, for example a gap, obstacles to rotation of the rotating plugs during refueling operations. The system includes an ultrasound reflector configured in the form of a ring on which at least one row of vertical cylindrical rods is arranged. The ring is attached to one of the thermal screens surrounding the reactor core, preferably one proximate to the nuclear reactor vessel. The spacing at which the cylindrical rods are arranged in the row is less than the spacing between the assemblies.

An in-core instrumentation system for a reactor module includes a plurality of in-core instruments connected to a containment vessel and a reactor pressure vessel at least partially located within the containment vessel. A reactor core is housed within a lower head that is removably attached to the reactor pressure vessel, and lower ends of the in-core instruments are located within the reactor core. The in-core instruments are configured such that the lower ends are concurrently removed from the reactor core as a result of removing the lower head from the reactor pressure vessel.

An in-core instrumentation system for a reactor module includes a plurality of in-core instruments connected to a containment vessel and a reactor pressure vessel at least partially located within the containment vessel. A reactor core is housed within a lower head that is removably attached to the reactor pressure vessel, and lower ends of the in-core instruments are located within the reactor core. The in-core instruments are configured such that the lower ends are concurrently removed from the reactor core as a result of removing the lower head from the reactor pressure vessel.

A method for detecting a leak in a cladding tube in a nuclear reactor is described. The method is well-suited for use in a reactor having a plurality of cladding tubes housed in a plurality of linearly arranged channels for flowing coolant past the cladding tubes. The method includes monitoring the channels for the occurrence of an increase in radiation above a selected base line indicative of the presence of at least one fission product in the coolant in at least one of the plurality of channels, and monitoring the channels for the occurrence of time dependent changes in the strength of radiation in the coolant above the base line along the length of the at least one of the plurality of channels. The leak location is calculated by triangulating the radiation readings from a fixed linear array of detectors positioned adjacent to the channels to determine the location of the strongest radiation reading and the location along the length of the channel where the increase in radiation occurred.

A method for detecting a leak in a cladding tube in a nuclear reactor is described. The method is well-suited for use in a reactor having a plurality of cladding tubes housed in a plurality of linearly arranged channels for flowing coolant past the cladding tubes. The method includes monitoring the channels for the occurrence of an increase in radiation above a selected base line indicative of the presence of at least one fission product in the coolant in at least one of the plurality of channels, and monitoring the channels for the occurrence of time dependent changes in the strength of radiation in the coolant above the base line along the length of the at least one of the plurality of channels. The leak location is calculated by triangulating the radiation readings from a fixed linear array of detectors positioned adjacent to the channels to determine the location of the strongest radiation reading and the location along the length of the channel where the increase in radiation occurred.

A system for servicing a nuclear reactor module comprises a crane operable to attach to the nuclear reactor module, wherein the crane includes provisions for routing signals from one or more sensors of the nuclear reactor module to one or more sensor receivers.

A system for servicing a nuclear reactor module comprises a crane operable to attach to the nuclear reactor module, wherein the crane includes provisions for routing signals from one or more sensors of the nuclear reactor module to one or more sensor receivers.