Abstract: A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

Abstract: A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

Abstract: A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

Abstract: A core shroud is provided, which includes a number of planar members, a number of unitary corners, and a number of subassemblies each comprising a combination of the planar members and the unitary corners. Each unitary corner comprises a unitary extrusion including a first planar portion and a second planar portion disposed perpendicularly with respect to the first planar portion. At least one of the subassemblies comprises a plurality of the unitary corners disposed side-by-side in an alternating opposing relationship. A plurality of the subassemblies can be combined to form a quarter perimeter segment of the core shroud. Four quarter perimeter segments join together to form the core shroud.

Abstract: An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

Abstract: An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

Abstract: An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

Abstract: A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

Abstract: A shipping container is provided for a hexagonal nuclear fuel assembly including a top nozzle having a top end, an outer barrel, an external shoulder, and an inner barrel; a plurality of grids which support fuel rods; and a bottom nozzle having an internal shoulder within a recess, a spherical taper, and a bottom end. The container may include a housing, a support for the fuel assembly, a top nozzle holder secured to the support, plural grid supports secured to the support, plural clamping frames for clamping the grids, plural guide plates for guiding the fuel assembly between adjacent grid supports, and a bottom nozzle holder secured to the support. The top nozzle holder may include a shoulder holder for holding the external shoulder, an end holder for enclosing and holding the top end, and a shoulder clamp for clamping the shoulder holder to the support.

Abstract: A shipping container is provided for a hexagonal nuclear fuel assembly including a top nozzle having a top end, an outer barrel, an external shoulder, and an inner barrel; a plurality of grids which support fuel rods; and a bottom nozzle having an internal shoulder within a recess, a spherical taper, and a bottom end. The container may include a housing, a support for the fuel assembly, a top nozzle holder secured to the support, plural grid supports secured to the support, plural clamping frames for clamping the grids, plural guide plates for guiding the fuel assembly between adjacent grid supports, and a bottom nozzle holder secured to the support. The top nozzle holder may include a shoulder holder for holding the external shoulder, an end holder for enclosing and holding the top end, and a shoulder clamp for clamping the shoulder holder to the support.

Abstract: A shipping container is provided for a hexagonal nuclear fuel assembly including a top nozzle having a top end, an outer barrel, an external shoulder, and an inner barrel; a plurality of grids which support fuel rods; and a bottom nozzle having an internal shoulder within a recess, a spherical taper, and a bottom end. The container may include a housing, a support for the fuel assembly, a top nozzle holder secured to the support, plural grid supports secured to the support, plural clamping frames for clamping the grids, plural guide plates for guiding the fuel assembly between adjacent grid supports, and a bottom nozzle holder secured to the support. The top nozzle holder may include a shoulder holder for holding the external shoulder, an end holder for enclosing and holding the top end, and a shoulder clamp for clamping the shoulder holder to the support.

Abstract: A replacement guide pin assembly is provided for aligning a nuclear fuel assembly with an upper core plate of a nuclear reactor core. One embodiment of the guide pin assembly includes an elongated guide pin body, a ferrule, and a lock screw. The guide pin body has a lower expandable base insertable within a hole in the top nozzle, and capable of expanding radially outwardly relative to a longitudinal axis of the guide pin body to provide an interference fit with the top nozzle. The ferrule is insertable within the top nozzle hole, interfitted with the guide pin body, and capable of imparting a radially and outwardly directed force on its lower expandable base to expand it within the hole of the top nozzle and thereby secure the guide pin body to the top nozzle in response to a predetermined displacement of the ferrule relative to the guide pin body along its longitudinal axis.

Abstract: A shipping container is provided for use in containing and supporting a nuclear core component assembly, such as a control or poison assembly. The shipping container includes a separate rigid cylindrical body and lid of plastic material, a plurality of elongated tubes of plastic material, and foam plastic rigid flat cylindrical spacer plates. The tubes are inserted into the body for receiving and stabilizing elongated rods of the core component assembly. The spacer plates are disposed stationarily within and transversely across the body and spaced apart from one another axially along the body. Each plate has a plurality of openings therethrough for receiving and disposing the tubes in transverse side-by-side spaced relationship with respect to one another in, and extending between a closed bottom and an open top of, the body. The plates thus laterally space and support the rods when received in the tubes.