Westinghouse Electric Corporation

Theodore W Nylund

David V Lambert

Joseph V Cioffi

Damon E Haley, Jr

John W Byers

Robert F Barry

William E Kirby

Glenn D Doss

Wilson, John F

Susan C Delzell

Kendell L McDill

David H Field

An automated fuel assembly loader, capable of patterned loading, moves nuclear fuel rods in a loading direction between a fuel rod skeleton defining an array of receptacles for the fuel rods, and a fuel rod magazine supplying or receiving the fuel rods. A table supports the fuel rod skeleton at a loading position. A movable carriage having a line of individual fuel rod engaging devices moves a subset of fuel rods along the line forward in the loading direction. The rods are selected via a pattern stored in a controller. Selection devices such as pneumatic clamps mechanically couple the selected engaging devices to the carriage for movement while others are left behind. A ball screw carriage drive arrangement moves the carriage parallel to the loading direction and a jack screw positioning drive displaces the carriage perpendicular to the line of fuel rods. A controller is coupled to the carriage drive and to the selection devices, and stores data defining a preset pattern of receptacles in the array, operating the selection devices for actuating a group of engaging devices corresponding to the pattern. The controller also controls displacement speed, permitting patterned loading of the skeleton, for example to obtain a particular pattern of fuel rod enrichments, the controller moving line by line through an array of fuel rod receptacles in the skeleton.

Automatic fuel assembly loader

Apparatus for loading fuel rods in a desired enrichment pattern includes a carrousel, an elongated fuel rod storage magazine, and a fuel rod verify and feed workstation and a magazine holder and indexing mechanism disposed between the carrousel and the magazine. The carrousel has a plurality of gondolas movable mounted thereon for stocking fuel rods of known enrichments. The magazine defines a matrix of elongated slots open at their forward ends for receiving fuel rods. The workstation defines a fuel rod feed path extending between the carrousel and the magazine and is adapted to receive successively one at a time along the feed path at its upstream end fuel rods from selected ones of the carrousel gondolas. The workstation includes an optical scanning and reading unit located along the feed path for verifying the identity of the fuel rods successively one at a time and a fuel rod feeding mechanism for successively feeding one at a time along the feed path the verified fuel rods into selected ones of the slots in the magazine. The magazine holder and indexing mechanism movably supports the magazine and is actuatable for moving the magazine along X-Y axes to successively align one at a time selected one of its slots with the feed path for loading in the magazine the successive fuel rods in a desired enrichment pattern.

Automated nuclear fuel rod pattern loading system

Apparatus for loading fuel rods in a desired enrichment pattern includes a carrousel, an elongated fuel rod storage magazine, and a fuel rod verify and feed workstation and a magazine holder and indexing mechanism disposed between the carrousel and the magazine. The carrousel has a plurality of gondolas movable mounted thereon for stocking fuel rods of known enrichments. The magazine defines a matrix of elongated slots open at their forward ends for receiving fuel rods. The workstation defines a fuel rod feed path extending between the carrousel and the magazine and is adapted to receive successively one at a time along the feed path at its upstream end fuel rods from selected ones of the carrousel gondolas. The workstation includes an optical scanning and reading unit located along the feed path for verifying the identity of the fuel rods successively one at a time and a fuel rod feeding mechanism for successively feeding one at a time along the feed path the verified fuel rods into selected ones of the slots in the magazine. The magazine holder and indexing mechanism movably supports the magazine and is actuatable for moving the magazine along X-Y axes to successively align one at a time selected ones of its slots with the feed path for loading in the magazine the successive fuel rods in a desired enrichment pattern.

A water cross for delivering non-boiling water to the center of a BWR fuel assembly for improved moderation and fuel economy. A cruciform skeleton is assembled from grid straps and connecting straps positioned at axial locations along stiffening rods. The skeleton is inserted into a flow channel to provide support for rectangular or square water tubes which are inserted through the skeleton into the flow channel to form an internal water cross. A method for forming a water cross is also disclosed.

Cruciform skeleton and water cross for a BWR fuel assembly

A nuclear fuel assembly includes and upper yoke, a base, an elongated, outer flow channel disposed substantially along the entire length of the fuel assembly and an elongated, internal, central water cross, formed by four, elongated metal angles, that divides the nuclear fuel assembly into four, separate, elongated fuel sections and that provides a centrally disposed path for the flow of subcooled neutron moderator along the length of the fuel assembly. A separate fuel bundle is located in each of the four fuel sections and includes an upper tie plate, a lower tie plate and a plurality of elongated fuel rods disposed therebetween. Preferably, each upper tie plate is formed from a plurality of interconnected thin metal bars and includes an elongated, axially extending pin that is received by the upper yoke of the fuel assembly for restraining lateral motion of the fuel bundle while permitting axial movement of the fuel bundle with respect to the outer flow channel. The outer flow channel is fixedly secured at its opposite longitudinal ends to the upper yoke and to the base to permit the fuel assembly to be lifted and handled in a vertical position without placing lifting loads or stresses on the fuel rods. The yoke, removably attached at the upper end of the fuel assembly to four structural ribs secured to the inner walls of the outer flow channel, includes, as integrally formed components, a lifting bail or handle, laterally extending bumpers, a mounting post for a spring assembly, four elongated apertures for receiving with a slip fit the axially extending pins mounted on the upper tie plates and slots for receiving the structural ribs secured to the outer flow channel. Locking pins securely attach the yoke to the structural ribs enabling the fuel assembly to be lifted as an entity.

Nuclear fuel assembly

Method and apparatus for adjusting the level of fuel rods in a fuel assembly which includes a tool having an end insertable between a fuel assembly nozzle plate and the exposed ends of fuel rods. The insertable end of the tool includes stationary and movable plates, the movable plate having a portion which rests on flanges in a forked end of the stationary plate while the other end of said movable plate is bent in a manner such that it lies above the stationary plate. A pair of gears are located in the space defined by the spaced ends of said plates, and screw threaded shafts extend through threaded openings in the movable plate and into gears located in the space between the ends of the plates, so that when one of the shafts is rotated, the force transmitted through said gears causes the other shaft to rotate and the coaction of both threaded shafts thus causes the movable plate to move in a direction away from the stationary plate, and in so doing, cause the fuel rod in contact with the movable plate to be moved in an axial direction and into a position where the end thereof lies in the same plane as the ends of other fuel rods in the assembly.

Growing community of inventors

Columbia, SC, United States of America

Theodore W Nylund