Abstract: An embodiment of the present invention takes the form of a system that allows for simultaneously assembling or disassembling multiple segmented nuclear fuel rods (hereinafter “segmented rods”). An embodiment of the present invention, may receive, secure, and move the segmented rods into a position that allows for performing the tasks of either assembly or disassembly, allowing for an operator to use a tool to complete the aforementioned tasks.

Abstract: A pressurized water nuclear reactor fuel assembly designed to burn mixed oxide fuel that employs a fully annular fuel pellet stack in the fuel rods, and radial enrichment zoning within the assembly such that the intra-assembly rod power distribution is relatively smooth regardless of the characteristics of the adjacent assemblies.

Abstract: Example embodiments are directed to fuel assembly components and nuclear fuel bundles including the fuel assembly components. Example embodiments of a fuel assembly component may include a cylindrical device having first and second ends and a mounting assembly on the first end of the cylindrical device configured to attach to and detach from a partial length fuel rod. Example embodiments of a nuclear fuel bundle may include an upper tie plate, a lower tie plate, at least one full-length fuel rod, at least one partial length fuel rod, and a fuel assembly component.

Abstract: A device and technique for placing and moving a ferromagnetic element in an annulus between coaxially arranged cylindrical tubes. The device includes an electromagnetic ram moved along the interior of a cylindrical tube. The movable ferromagnetic element is magnetically coupled to the electromagnetic ram and moved by magnetic force to a location in the annulus defined by the tubes and magnetically coupled to the electromagnetic ram for movement in and removal from the annulus.

Abstract: Method of fabricating a fuel rod, comprising providing an effective amount of a metal oxide in the fuel rod to generate steam and mitigate the tendency for secondary hydriding. Fuel rods fabricated according to the method of the invention are also provided.

Abstract: The present invention relates to a miniaturized nuclear utilizing improved pressure tube structural members. More particularly, the present invention relates to a new miniaturized nuclear reactor utilizing novel structural members that are used to support the loads and stresses of multiple nuclear reactor fuel channel pressure tubes and calandria tubes in a moderator.

Abstract: A fuel rod for nuclear reactors which contains UO.sub.2 or a mixed-oxide (MOX) of UO.sub.2 and PuO.sub.2 as a nuclear fuel and a combustible reactivity control material e.g., Gd.sub.2 O.sub.3. A plurality of hollow UO.sub.2 or MOX pellets each having a hole along its central axis are spitted with a long bar of Gd.sub.2 O.sub.3 to form a pellet stack, which is inserted and sealed in a cladding tube to form the fuel rod of the present invention. Since the Gd.sub.2 O.sub.3 bar can be manufactured in a non-nuclear fuel manufacturing facility, it is not required to provide two separate lines, i.e., a line for handling Gd.sub.2 O.sub.3 and a line for handling UO.sub.2 or MOX fuel, in one manufacturing facility. The optimum design for the performance of the nuclear fuel is possible by changing the diameter and/or Gd.sub.2 O.sub.3 concentration of the Gd.sub.2 O.sub.3 bar depending on the desired performance of the nuclear fuel.

Abstract: A fuel assembly of a pressurized water nuclear reactor includes at least two fuel rods, respectively, having a cladding tube of given outer and inner diameters and pellets of given outer diameter received in the cladding tube, the fuel rods being disposed in the fuel assembly at a given mutual spacing of center points thereof, a ratio of the given mutual spacing of the center points of the fuel rods to the outer diameter of the cladding tube being in a range between 1.35 and 1.37.

Abstract: A gas cooled nuclear fuel element having a particle fuel retention device which acts as a passive restraint in the event of failure of hot frit. A particle fuel retention device is positioned either in the annular space within the inner frit, in the end cap through which coolant gas flows, or attached to the end cap and extending axially beyond the fuel element.

Abstract: A nuclear fuel element for a particle bed reactor. Concentric inner and outer porous cylinders attached at either end define an annulus therebetween that contains a fuel particle bed of nuclear fuel material. The outer porous cylinder is provided with fins that extend radially outward along its entire length. A nonporous cylinder is attached to the outer porous cylinder at either end and is positioned around the outer porous cylinder so as to be concentric therewith. Flexible fins extend radially inward form the nonporous cylinder along its entire length and contact the fins on the outer porous cylinder for conduction of heat to heat removal tubes on the outer surface of the nonporous cylinder. The heat removal tubes allow bimodal cooling of the particle bed reactor.

Abstract: The fuel element comprises a plurality of modular capsules (5) arranged in sequence axially within a sheath (2). Each of the capsules (5) comprises a tubular case (10) closed at both ends by a porous element (13, 14) and enclosing a stack of pellets (11) in contact with the inner surface of the case (10) without radial clearance. The outside diameter of the capsules (5) is such that a very small radial clearance exists between the outer surface of the capsule (5) and the inner surface of the sheath (2).

Abstract: A fuel pellet for a nuclear reactor fuel rod is fabricated with smooth and gently sloping surfaces having no sharp edges or areas of high stress concentration. The bearing surfaces of the fuel pellets are contoured so that the pellets are easily stacked within a fuel rod and permit pivoting action between the fuel pellets. The fuel pellets are stacked end to end in a fuel rod which is incorporated into a fuel assembly for a nuclear reactor.

Abstract: An improved end plug is provided for a nuclear fuel rod assembly. The end plug is of an integral construction having an upper shoulder portion which abuts the top edge of a fuel tube and a circular body portion adapted to be inserted into the end of the fuel tube in a force fitting relationship. A flat is provided on the lower body portion so as to define a gap between the lower body portion and the inner wall of the fuel tube upon partial insertion of the plug into the tube, the gap providing an orifice for introducing an inert-gas under pressure into the tube. Upon total insertion of the lower body portion of the plug into the tube, the gap is eliminated and metal-to-metal contact is made between the lower body portion of the plug and the end of the fuel tube for sealing the pressurized gas and a nuclear fuel within the fuel tube.