| Patent application number | Description | Published |
|---|
| 20080205577 | Systems for aligning and handling fuel rods within a nuclear fuel bundle - In a spent fuel pool of a nuclear power plant, there is provided a system for aligning a nuclear fuel bundle and handling selected fuel rods within the fuel bundle. The bundle includes water rods, full-length and part-length fuel rods extending through a plurality of fuel spacers provided between top and bottom ends of the bundle, each spacer having a plurality of cells accommodating corresponding fuel and water rods. The system includes a bundle alignment system for aligning the fuel rods and water rods, a rod grapple tool to extract selected part-length rods from the bundle, and a fuel rod guide block slidable onto the top end of the bundle for protecting an uppermost fuel spacer of the bundle, and for aligning fuel rods within individual cells of all the fuel spacers in the fuel bundle | 08-28-2008 |
| 20090060113 | DEBRIS SHIELD UPPER TIE PLATE FOR NUCLEAR FUEL ASSEMBLY AND METHOD TO SHIELD ASSEMBLY FROM DEBRIS - A nuclear reactor fuel bundle assembly including: a fuel bundle including an array of fuel rods and water rods mounted in an upper tie plate and housed in walls of a channel, and a pore type debris shield mounted at least partially in the channel, above or below the upper tie plate, the shield extending to or over the walls of the channel, whereby deflecting and/or capturing falling debris from entering the fuel assembly, wherein the shield is design to be durable, yet flexible, and porous. | 03-05-2009 |
| 20090060114 | DEBRIS SHIELD FOR UPPER TIE PLATE IN A NUCLEAR FUEL BUNDLE AND METHOD FOR FILTERING DEBRIS - A nuclear reactor fuel assembly including: an upper tie plate having apertures to receive and support fuel rods of a fuel bundle; the fuel bundle includes an array of the fuel rods mounted and housed in the walls of a channel, and a load bearing or non-load bearing debris shield may be mounted in the upper tie plate, wherein the debris shield is porous to prevent the passage of debris. The debris shield is mounted in the frame of the upper tie plate. The debris shield can be either a removable unit, or it can be attached as a permanent integrated structure within the upper tie plate. The upper tie plate frame is also porous, e.g., has small vertical openings to allow fluid to pass through the frame and block passage of debris. The openings in the frame increase the effective flow area of passages through the upper tie plate and thereby compensate or offset any flow restrictions due to the debris shield. Preventing debris falling into the fuel bundle is expected to assure the operational life of the fuel assembly by reducing the risk of fuel rod failure and premature discharge from the reactor core. | 03-05-2009 |
| 20090080590 | METHOD AND APPARATUS TO SHIELD A NUCLEAR FUEL ASSEMBLY WITH REMOVABLE DEBRIS SHIELD IN UPPER TIE - A method to capture, retain and remove debris falling into a nuclear reactor fuel bundle assembly including a bundle of fuel rods mounted below an upper tie plate and housed in a hollow metal channel, the method includes: inserting a debris shield in the upper tie plate; maintaining the shield in the upper tie plate and above the fuel rods, and water rods, while the fuel bundle assembly is in an operating nuclear reactor core; capturing debris falling in the fuel assembly on the debris shield; after capturing the debris, removing the fuel bundle assembly with the inserted debris shield from the nuclear reactor core to a maintenance/fuel inspection pool and thereafter removing the debris shield from the upper tie plate, cleaning and then reinserting the cleaned debris shield back into the upper tie plate, and moving the fuel bundle assembly from the maintenance/fuel inspection pool back into the nuclear reactor core. | 03-26-2009 |
| 20090092217 | METHOD TO SHIELD NUCLEAR FUEL ASSEMBLY WITH REMOVABLE DEBRIS SHIELD IN UPPER TIE PLATE - A method to prevent debris falling into a nuclear reactor fuel assembly including a bundle of fuel rods mounted below an upper tie plate and housed in a channel including: inserting a debris shield in the upper tie plate; maintaining the shield in the upper tie plate and above the fuel rods, while the fuel assembly is in an operating nuclear reactor core; flowing coolant through the bundle and the debris shield during operation of the nuclear reactor core, and capturing or deflecting debris falling in the fuel assembly with the debris shield. | 04-09-2009 |
| 20090139969 | Laser welding of castings to minimize distortion - A process of using laser welding in the assembly of boiling water reactor fuel debris filters is disclosed. The laser welding process minimizes the distortion of the debris filter cast lower tie plate by applying minimal heat during the welding. Fixtures hold the cast lower tie plate through four degrees of motion under a constant controlled laser source during welding. The welding process also reduces the potential for stress corrosion cracking resulting from crevices in partial penetration welds that might occur in a laser welding process. | 06-04-2009 |
| 20100232564 | SYSTEMS FOR ALIGNING AND HANDLING FUEL RODS WITHIN A NUCLEAR FUEL BUNDLE - In a spent fuel pool of a nuclear power plant, there is provided a system for aligning a nuclear fuel bundle and handling selected fuel rods within the fuel bundle. The bundle includes water rods, full-length and part-length fuel rods extending through a plurality of fuel spacers provided between top and bottom ends of the bundle, each spacer having a plurality of cells accommodating corresponding fuel and water rods. The system includes a bundle alignment system for aligning the fuel rods and water rods, a rod grapple tool to extract selected part-length rods from the bundle, and a fuel rod guide block slidable onto the top end of the bundle for protecting an uppermost fuel spacer of the bundle, and for aligning fuel rods within individual cells of all the fuel spacers in the fuel bundle. | 09-16-2010 |
| 20110243293 | Systems and Methods for Servicing a Fuel Assembly in a Light Water Reactor - Systems and methods for servicing a fuel assembly in a light water reactor include those for controlling flow through a fuel assembly to maintain debris in the fuel assembly during removal and transportation of the fuel assembly, those for discharging debris from the fuel assembly, and those for isolating and sampling the water chemistry of a fuel assembly. An exemplary system includes a closure device configured to seal a mast to a fuel assembly to surround the upper opening of the fuel assembly and provide a flow control channel between a void in the mast and a lower opening in a lower tie plate. | 10-06-2011 |
