This disclosure enables a creation of a detachable connection between a linear motor tubular armature and a vertical cylindrical rod of an actuator of a control and protection system of a nuclear reactor. Such configuration reduces a dose load on a member of personnel, as well as provides an increase in reliability of a coupling of the linear motor tubular armature and the vertical cylindrical rod in conditions of high temperature and radiation.

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 magnetic fields and be moveable across a full stroke length of the control element in the reactor. A motor may spin a linear screw to move the induction coils on a vertical travel nut. 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. Operation includes moving the induction coils with a linear screw 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.

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 magnetic fields and be moveable across a full stroke length of the control element in the reactor. A motor may spin a linear screw to move the induction coils on a vertical travel nut. 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. Operation includes moving the induction coils with a linear screw 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.

A control rod drive mechanism having a torque tube, a control rod assembly including a connecting rod and a spider, a lock cam assembly rotatably secured to a bottom end of the connecting rod and including a locking cam, and a locking collar disposed non-rotatably within the spider, the locking collar including a locking recess with an entry slot, wherein in a first axial position the lock cam assembly is rotatable with respect to the torque tube, and a second axial position the lock cam assembly is non-rotatable with respect to the torque tube.

A control rod drive mechanism having a torque tube, a control rod assembly including a connecting rod and a spider, a lock cam assembly rotatably secured to a bottom end of the connecting rod and including a locking cam, and a locking collar disposed non-rotatably within the spider, the locking collar including a locking recess with an entry slot, wherein in a first axial position the lock cam assembly is rotatable with respect to the torque tube, and a second axial position the lock cam assembly is non-rotatable with respect to the torque tube.

A control rod drive mechanism having a torque tube, a control rod assembly including a connecting rod disposed within the torque tube and including an annular collar defining a key slot, an elongated key that is slidably receivable within the key slot, a lock cam assembly rotatably secured to a top end of the connecting rod and including a locking cam, and a holdout collar disposed non-rotatably within the torque tube, the holdout collar including a locking recess with an entry slot, wherein in a first axial position the lock cam assembly is rotatable with respect to the torque tube, and a second axial position the lock cam assembly is non-rotatable with respect to the torque tube.

A control rod drive mechanism having a torque tube, a control rod assembly including a connecting rod disposed within the torque tube and including an annular collar defining a key slot, an elongated key that is slidably receivable within the key slot, a lock cam assembly rotatably secured to a top end of the connecting rod and including a locking cam, and a holdout collar disposed non-rotatably within the torque tube, the holdout collar including a locking recess with an entry slot, wherein in a first axial position the lock cam assembly is rotatable with respect to the torque tube, and a second axial position the lock cam assembly is non-rotatable with respect to the torque tube.

A control rod drive mechanism having a torque tube with an inner surface defining a central bore, a control rod assembly including a connecting rod including a cam extending radially-outwardly therefrom and an annular collar defining a key slot, an elongated key that is slidably receivable within the key slot, and a holdout collar disposed non-rotatably within the torque tube and defining a locking recess, wherein the connecting rod is axially-movable with respect to the torque tube between a first position in which the elongated key is disposed within the key slot so that the connecting rod is non-rotatable with respect to the torque tube, and a second position in which the elongated key is removed from the key slot and the connecting rod is rotatable with respect to the torque tube.

A nuclear power system includes a reactor vessel that includes a reactor core mounted within a volume of the reactor vessel. The reactor core includes one or more nuclear fuel assemblies configured to generate a nuclear fission reaction. The nuclear power system further includes a containment vessel sized to enclose the reactor vessel such that an open volume is defined between the containment vessel and the reactor vessel. A boron injection system is positioned in the open volume of the containment vessel and includes an amount of boron sufficient to stop the nuclear fission reaction or maintain the nuclear fission reaction at a sub-critical state. The boron injection system is positioned to deliver the amount of boron into the open volume.

A control rod assembly having a connecting rod, a spider, a plurality of control rods, a coupling sleeve secured to the connecting rod and including a body portion defining at least one cam pin, and a barrel cam defining a cam track, the barrel cam being rotatably secured to the spider. The cam track includes a first camming surface and a second camming surface that are configured so that the barrel cam rotates in a first direction as the at least one cam pin slides along the first and second camming surfaces. The barrel cam rod is rotatable between a first position in which the spider is connected to the connecting rod and a second position in which the spider is disconnected from the connecting rod.