Abstract: In some embodiments, a nuclear reactor vessel comprises a containment vessel for a reactor pressure vessel (RPV); a control rod drive mechanism (CRDM) located in the containment vessel, the CRDM including drive motors configured to move control rods into and out of a nuclear reactor core located in the RPV; and a partition extending across a portion of the containment vessel configured to retain the drive motors in a separate fluid-tight barrier region within the containment vessel. Other embodiments may be disclosed and/or claimed.

Abstract: A pressurized water reactor (PWR) comprises a pressure vessel containing primary coolant water. A nuclear reactor core is disposed in the pressure vessel and includes a plurality of fuel assemblies. Each fuel assembly includes a plurality of fuel rods containing a fissile material. A control system includes a plurality of control rod assemblies (CRA's). Each CRA is guided by a corresponding CRA guide structure. A support element is disposed above the CRA guide structures and supports the CRA guide structures. The pressure vessel may be cylindrical, and the support element may comprise a support plate having a circular periphery supported by the cylindrical pressure vessel. The CRA guide structures suitably hang downward from the support plate. The lower end of each CRA guide structure may include alignment features that engage corresponding alignment features of the upper end of the corresponding fuel assembly.

Abstract: Disclosed is a control rod drive mechanism. More specifically, the control rod drive mechanism includes a guide member 100 disposed in a nuclear reactor to receiving a drive shaft 2; a latch assembly 200 disposed in the guide member 100 to enable the drive shaft 2 to be withdrawn and inserted; a supporting member 300 connected to the guide member 100 to cover the drive shaft 2 and to support the latch assembly 200; and a plurality of coil housings 400 spaced apart and connected to the guide member 100 to cover the latch assembly 200, and each having a coil 410 built therein.

Abstract: According to one embodiment, each of driving mechanisms is differently connected to one of control rods located in a nuclear reactor. A driving mechanism drives a connected control rod to be inserted and withdrawn with a high-pressure driving water by opening and closing control valves thereof. Driving time data of unlatch, insertion, withdrawal and settle of each control rod, is stored. The driving time data is measured by a test of insertion and withdrawal at a periodical inspection before starting operation of the nuclear reactor. At least one is selected from the control rods, based on a command to select and drive a control rod. A timing table that prescribes timings to open and close each control valve to unlatch, insert, withdraw and settle the selected control rod, is created based on the driving time data thereof. The selected control rod is driven based on the timing table.

Abstract: Disclosed embodiments include electromagnetic flow regulators for regulating flow of an electrically conductive fluid, systems for regulating flow of an electrically conductive fluid, methods of regulating flow of an electrically conductive fluid, nuclear fission reactors, systems for regulating flow of an electrically conductive reactor coolant, and methods of regulating flow of an electrically conductive reactor coolant in a nuclear fission reactor.

Abstract: Disclosed embodiments include electromagnetic flow regulators for regulating flow of an electrically conductive fluid, systems for regulating flow of an electrically conductive fluid, methods of regulating flow of an electrically conductive fluid, nuclear fission reactors, systems for regulating flow of an electrically conductive reactor coolant, and methods of regulating flow of an electrically conductive reactor coolant in a nuclear fission reactor.

Abstract: In a nuclear reactor, an internal control rod drive mechanism (CRDM) includes a motor and a hydraulically driven element connected by at least one hydraulic line with at least one hydraulic connector disposed on a mounting plate of the internal CRDM. A support element mounted in the nuclear reactor includes at least one hydraulic connector. The internal CRDM is supported on the support element by its mounting plate with each hydraulic connector of the internal CRDM mated with a corresponding hydraulic connector of the support element. The hydraulically driven element may be a piston controlling SCRAM, driven by coolant water, and the coolant water pressure in the at least one hydraulic line is higher than the coolant water pressure in the nuclear reactor. The mating of each hydraulic connector of the internal CRDM with a corresponding hydraulic connector of the support element may be a leaky mating that leaks coolant water into the pressure vessel.

Abstract: A standoff supporting a control rod drive mechanism (CRDM) in a nuclear reactor is connected to a distribution plate which provides electrical power and hydraulics. The standoff has connectors that require no action to effectuate the electrical connection to the distribution plate other than placement of the standoff onto the distribution plate. This facilitates replacement of the CRDM. In addition to the connectors, the standoff has alignment features to ensure the CRDM is connected in the correct orientation. After placement, the standoff may be secured to the distribution plate by bolts or other fasteners. The distribution plate may be a single plate that contains the electrical and hydraulic lines and also is strong enough to provide support to the CRDMs or may comprise a stack of two or more plates.

Abstract: Embodiments include electromagnetic flow regulators for regulating flow of an electrically conductive fluid, systems for regulating flow of an electrically conductive fluid, methods of regulating flow of an electrically conductive fluid, nuclear fission reactors, systems for regulating flow of an electrically conductive reactor coolant, methods of regulating flow of an electrically conductive reactor coolant in a nuclear fission reactor, and methods of fabricating an electromagnetic flow regulator for regulating flow of an electrically conductive fluid.

Abstract: Disclosed embodiments include electromagnetic flow regulators for regulating flow of an electrically conductive fluid, systems for regulating flow of an electrically conductive fluid, methods of regulating flow of an electrically conductive fluid, nuclear fission reactors, systems for regulating flow of an electrically conductive reactor coolant, and methods of regulating flow of an electrically conductive reactor coolant in a nuclear fission reactor.

Abstract: Disclosed embodiments include electromagnetic flow regulators for regulating flow of an electrically conductive fluid, systems for regulating flow of an electrically conductive fluid, methods of regulating flow of an electrically conductive fluid, nuclear fission reactors, systems for regulating flow of an electrically conductive reactor coolant, and methods of regulating flow of an electrically conductive reactor coolant in a nuclear fission reactor.

Abstract: A magnetic jack control rod drive rod drive system having the magnetic coils that operate the moving parts of the drive system wound from anodized aluminum magnet wire or ceramic coated nickel clad copper and enclosed within a hermetically sealed housing that is pressurized with helium.

Abstract: A control rod drive mechanism (CRDM) comprises a lead screw, a motor threadedly coupled with the lead screw to linearly drive the lead screw in an insertion direction or an opposite withdrawal direction, a latch assembly secured with the lead screw and configured to (i) latch to a connecting rod and to (ii) unlatch from the connecting rod, the connecting rod being free to move in the insertion direction when unlatched, and a release mechanism configured to selectively unlatch the latch assembly from the connecting rod.

Abstract: A control rod drive mechanism (CRDM) for use in a nuclear reactor, the CRDM comprising: a connecting rod connected with at least one control rod; a lead screw; a drive mechanism configured to linearly translate the lead screw; an electromagnet coil assembly; and a latching assembly that latches the connecting rod to the lead screw responsive to energizing the electromagnet coil assembly and unlatches the connecting rod from the lead screw responsive to deenergizing the electromagnet coil assembly. The latching assembly is secured with and linearly translates with the lead screw, while the electromagnet coil assembly does not move with the lead screw. The electromagnet coil assembly is at least coextensive with a linear translation stroke over which the drive mechanism is configured to linearly translate the lead screw.

Abstract: A control rod drive contains a drive housing, in which a control rod carrying element is moveable between a basic position and an end position. The control rod carrying element is guided over a portion in a throttle bush. Formed across the throttle bush is a free flow cross section for a pressure fluid which varies in dependence on a position of the control rod carrying element. During an emergency shutdown, in which the control rod carrying element is moved hydraulically via a pressure fluid, the flow resistance for the pressure fluid is reduced, when the control rod carrying element reaches the end position. Therefore, a braking of the control rod carrying element takes place before it reaches the end position, thus reducing mechanical loads during braking. A flow resistance change takes place via a variable outside diameter of the control rod carrying element and/or by a bypass orifice.

Abstract: To reduce the manufacturing processes of a control rod and shorten the time required for manufacturing a control rod, for the lower part support member 7, the thin parts 11A and 11B are formed in the neighborhood of each of the left and right sides of the window 8. In the left and right sides of the pull-up handle 9, the grooves 17A and 17B are formed respectively. The groove 17B is deeper than the groove 17A. The thin part 11A is fitted into the groove 17A and the thin part 11B is fitted into the groove 17B. The gap formed between the end of the thin part 11B and the bottom of the groove 17B is larger than the gap formed between the end of the thin part 11A and the bottom of the groove 17A. Therefore, the thin part 11A can be simply fitted into the groove 17A.

Abstract: A fast-acting nuclear reactor control device for moving and positioning a fety control rod to desired positions within the core of the reactor between a run position in which the safety control rod is outside the reactor core, and a shutdown position in which the rod is fully inserted in the reactor core. The device employs a hydraulic pump/motor, an electric gear motor, and solenoid valve to drive the safety control rod into the reactor core through the entire stroke of the safety control rod. An overrunning clutch allows the safety control rod to freely travel toward a safe position in the event of a partial drive system failure.

Abstract: Mechanism for displacing and securing the rod of a nuclear reactor control bar, comprising an enclosure coaxial with the rod and forming a hydraulic cylinder in which the rod slides while defining a decompression chamber, a device for mechanically securing the rod in its high position, and a positive displacement reciprocating pump inserted between the decompression chamber and the inside of the tank, whose piston is actuated electromagnetically means and causes at each backward and forward movement lifting of given amplitude of the rod and the device for securing the rod in the high position disengagable also electromagnetically.

Abstract: The reactor has a pressure vessel receiving a coolant and a reactor core. The core has vertically movable control rods to which absorber rods are secured. Each tubular control rod extends, with the interposition of an annular gap, around an immobile guide rod which is also tubular and which is longer than the control rod. To move the control rods, coolant is supplied from the pressure vessel under pressure to the interior of the guide rods. The annular chamber communicates by way of communicating bores with the interior of the associated guide rod and, by way of at least two annular restrictions providing different restrictors with the pressure vessel interior. One restrictor is disposed at the top end of the associated control rod and the other restrictor at the bottom end thereof.The control rods move axially upwards in response to an increasing quantity of coolant in the guide rod interiors and downwards in response to a decreasing quantity of coolant in the guide rod interiors.

Abstract: An apparatus is disclosed which measures forces resisting the movement of pistons in a control rod drive mechanism in a nuclear reactor and which includes pressure sensing means and further includes hydraulic circuitry to divert pressurized fluid from a normal operating conduit to a selected shunt conduit containing a valve having a particular fluid control characteristic, said shunt conduit directing the fluid to a selected piston to move said piston and said pressure sensing means measuring the pressure of the fluid during the motion of said piston to give an indication of the force needed to achieve such motion.