A gripper a fuel element, comprises a housing, an inner part arranged inside the housing, the inner part and the housing being displaceable relative to one another in an axial direction, with the inner part movable between a first end position and a second end position, a catch member movable between a gripping position and a release position, a gripper spring between the housing inner part counteracting movement of the inner part from the second end position, or an intermediate position (Z) between the first and second end position, to the first end position, and a damping system comprising a first and second connecting member for connecting the damping system to the housing, inner part and/or the fuel element loading machine, and a spring member arranged on the first and/or the second connecting member counteracting movement of the inner part from an intermediate position (Z) to the second end position.

A gripper a fuel element, comprises a housing, an inner part arranged inside the housing, the inner part and the housing being displaceable relative to one another in an axial direction, with the inner part movable between a first end position and a second end position, a catch member movable between a gripping position and a release position, a gripper spring between the housing inner part counteracting movement of the inner part from the second end position, or an intermediate position (Z) between the first and second end position, to the first end position, and a damping system comprising a first and second connecting member for connecting the damping system to the housing, inner part and/or the fuel element loading machine, and a spring member arranged on the first and/or the second connecting member counteracting movement of the inner part from an intermediate position (Z) to the second end position.

Disclosed is a system for separating and coupling a top nozzle of a nuclear fuel assembly. There is provided a lock insert configured to support the top nozzle of the nuclear fuel assembly by being coupled to a guide hole provided in a flow channel plate of the top nozzle, the lock insert including: a body in a hollow shape; and an insertion part provided on a top portion of the body and inserted into the guide hole, wherein a circumference of the insertion part is variable in size, thereby being capable of being inserted into the guide hole. Accordingly, disassembly and reassembly of the top nozzle of the nuclear fuel assembly and the lock insert are simplified, thereby simplifying and reducing the number of processes involved therein. Accordingly, the system is effective for maintenance and repair of the nuclear fuel assembly.

A combined blade guide and exchange tool, include a blade guide tool having a lower end and an upper end and a plurality of frame rails supporting a pair of lower collet housings at a lower end of the blade guide tool. A pair of fuel support grapple actuating rods are supported between the plurality of frame rails and have a first end engaging a pair of collets within the pair of lower collet housings and a second end disposed at the upper end of the blade guide tool. A blade exchange tool is releasably mounted to the upper end of the blade guide tool and includes a pair of upper collets for engaging the pair of fuel support grapple actuating rods. The blade exchange tool further including a slider and hook assembly attached to a cable guided by the blade exchange tool and adapted for engaging a control rod.

An unlatching tool configured for actuating a movable section of a control rod drive shaft in a pressurized water reactor includes a base; a gripper assembly configured for gripping the movable section of the control rod drive shaft; a rod movably connecting the gripper assembly to the base; and a mechanical actuator fixed to the base and configured for rotating the rod to raise and lower the gripper assembly. A method for actuating a movable section of a control rod drive shaft includes installing an unlatching tool on the control rod drive shaft; latching the unlatching tool to a stationary section of the control rod drive shaft; and raising a rod connected to a gripper assembly to cause the gripper assembly to grip the movable section and move the movable section upward.

A gripper a fuel element, comprises a housing, an inner part arranged inside the housing, the inner part and the housing being displaceable relative to one another in an axial direction, with the inner part movable between a first end position and a second end position, a catch member movable between a gripping position and a release position, gripper spring between the housing inner part counteracting movement of the inner part from the second end position, or an intermediate position (Z) between the first and second end position, to the first end position, and a damping system comprising a first and second connecting member for connecting the damping system to the housing, inner part and/or the fuel element loading machine, and a spring member arranged on the first and/or the second connecting member counteracting movement of the inner part from an intermediate position (Z) to the second end position.

A gripper a fuel element, comprises a housing, an inner part arranged inside the housing, the inner part and the housing being displaceable relative to one another in an axial direction, with the inner part movable between a first end position and a second end position, a catch member movable between a gripping position and a release position, gripper spring between the housing inner part counteracting movement of the inner part from the second end position, or an intermediate position (Z) between the first and second end position, to the first end position, and a damping system comprising a first and second connecting member for connecting the damping system to the housing, inner part and/or the fuel element loading machine, and a spring member arranged on the first and/or the second connecting member counteracting movement of the inner part from an intermediate position (Z) to the second end position.

A method for preparing to reload a fast nuclear reactor with heavy liquid metal coolant includes extracting a reactor plug and extracting a removable reactor block. The method includes installing handling equipment to form an unloading path under radiation safety conditions. The reactor plug is extracted from the reactor monoblock housing and transported to a plug shaft. The removable reactor block is extracted from the reactor monoblock housing and transported to a block shaft for later disassembly.

A method for preparing to reload a fast nuclear reactor with heavy liquid metal coolant includes extracting a reactor plug and extracting a removable reactor block. The method includes installing handling equipment to form an unloading path under radiation safety conditions. The reactor plug is extracted from the reactor monoblock housing and transported to a plug shaft. The removable reactor block is extracted from the reactor monoblock housing and transported to a block shaft for later disassembly.

An in-vessel fuel transfer machine may be permanently affixed to a nuclear reactor and remain in place during power operations. The in-vessel fuel transfer machine may include a pantograph machine that positions a grapple in order to access any fuel socket location within the core and move any of the core assemblies between the core, an in-vessel fuel storage area, and a fuel elevator. The grapple may be positioned through a combination of movements, such as, rotating a rotating plug assembly, rotating the in-vessel fuel transfer machine, extending the pantograph arms, and shuttling the grapple along a leg. The grapple may be compliant to accommodate deformed core assemblies and may be configured to pivot to more closely align to an eccentric core assembly handling socket or be moveable in a horizontal plane to accommodate a deformed core assembly during insertion or withdrawal.