Abstract: A pair of openings are formed using an EDM technique. A pair of clamps are inserted into the openings and moved toward each other until such time as the inboard edges of the two openings are engaged. A pair of EDM cutters are used to cut a pair of slots which extend from one opening to the other. Upon completion of these slots, the sample, which remains clamped between the two clamps, is withdrawn and lowered back down the conduit to a remote collection point.

Abstract: A nuclear power plant fuel transfer tube quick operating remote closure device (10) comprised of a reducing ring (20) and a cover assembly (60). The reducing ring (20) is bolted to the transfer tube housing flange (12). Rotation of a chuck key advances jaws on the cover assembly (60) which feed closure latches (78) into a groove (40) on the reducing ring (20). The upper surface (80) of each latch (78) has a bevelled surface (82) corresponding to a bevelled surface (42) of the groove (40). As the latches (78) engage the groove bevelled surface (42), the entire cover assembly (60) is uniformly drawn toward the reducing ring (20). Machined seal faces (13, 30, 44, 68) and O rings (36, 74) provide a fluid and air tight seal between the transfer tube housing flange (12) and the sealing ring (20) and between the cover assembly (60) and the sealing ring (20).

Abstract: An irradiated steel pressurized nuclear reactor pressure vessel 10 is provided with a crack initiation retarding and crack extension retarding reactor vessel integrity girdle 20 or 120 made up of shoes or links 22, with mechanical take up joints (26 to 34a or 126 to 134a). Instead of pivoted shoe links 22, the girdle 120 may be made using constricting roller chain links 122. In any event, crack initiation and crack extension which may result from pressure loading or vessel material embrittled in the beltline region by neutron bombardment is retarded by maintenance of a prestress under the nozzles during all periods of operation of the reactor.

Abstract: A tool system features an EDM crack removal head which can be positioned within a nozzle/thermal sleeve and then oscillated in a vertical and horizontal directions to enable precise material removal, leaving the surface free of cracks and in a condition for rewelding if required. If a crack is found in a surface which is covered by a thermal sleeve, then a small specialized EDM cutting head, which can be delivered from the under side of the reactor head and has an ability to pass through the ID of the thermal sleeve, is used. The head enables the sleeve to be cut and allow a portion of the sleeve to be removed. The crack can then be removed using a crack removal type of head.

Abstract: A tool system features an EDM crack removal head which can be positioned within a nozzle/thermal sleeve and then oscillated in a vertical and horizontal directions to enable precise material removal, leaving the surface free of cracks and in a condition for rewelding if required. If a crack is found in a surface which is covered by a thermal sleeve, then a small specialized EDM cutting head, which can be delivered from the under side of the reactor head and has an ability to pass through the ID of the thermal sleeve, is used. The head enables the sleeve to be cut and allow a portion of the sleeve to be removed. The crack can then be removed using a crack removal type of head.

Abstract: A plug assembly for plugging the flow hole of a core support barrel employs a pair of plug members which are initially collapsable to permit positioning between the core support barrel and the adjacent thermal shield. The plug assembly is activated to a projected plugged configuration by pneumatic or hydraulic pressure to provide a sealing engagement by a cooperative arrangement between circumferential locking barbs and a sealing lip.

Abstract: A tool (78) for grasping a multiplicity of nuclear fuel rods (42) to remove them from a nuclear fuel assembly (32) and relocate them, preferably, into a fuel consolidation device (86). The tool has a gripper head (200) reciprocably guided within a shroud (80). A distinct jaw mechanism (216) for grasping each of the multiplicity of fuel rods is carried by a common frame (214) and actuated and controlled by a distinct means (232, 234, 242). A key feature of the gripper head is that each jaw mechanism (216) has an neck portion (244) to offset the actuation means (232, 234) from the moving jaw portion (220). The shroud carries alignment means (82, 206) for precisely orienting the tool relative to a targeted group of rods within the assembly, so that the spacing of the rods is maintained as they are pulled up into the shroud by the gripper head.

Abstract: An elongated canister (86) into which the fuel rods (42) from, preferably, two nuclear fuel assemblies (32) are inserted from above, and then passively consolidated within the canister such that at the lower end (88) the effective density of the rods is approximately double that of each fuel assembly. The canister includes a straight vertical back panel (308), side panels (312) having straight upper (310) and inwardly oriented, tapered lower portions (314), and a front panel (300) having straight upper (302) and tapered lower (304) portions. Spaced apart plates (90) extending between the front and back panels, and a temporary base (320), preferably titled from front to back, in conjunction with the generally funnel-shaped canister, operate to urge the rods close together while the rod pattern is transformed from square to triangular pitch.

Abstract: A system and method for handling nuclear fuel in which a consolidation stage (26), including a disassembly station (60), an interim transfer station (62) and a consolidation station (64), and a multiple rod pulling tool (78) and interim fuel transfer canister (86) are employed to remove fuel rods (42) from two fuel assemblies (32) and consolidate them into one storage box (96). A key feature of the disclosure is the alignment of the transfer canister (86) over the box (96) such that the canister base (92) with the weight of the consolidated rods, is released and lowered into a new position as the base of the storage box (96). A duel elevator arrangement (108, 110) is disclosed for moving the base (29) and box (96) to transfer the rods therebetween.

Abstract: A single guide tube and tube sheet tube, as an upper extension, carries a nuclear control rod in storage, poised for downward insertion into the guide tube. An inner tube, termed a bypass tube, is mounted within the cylindrical tube sheet tube and fitted closely about the control rod. Mounting connections between the upper and lower ends of the bypass tube and the tube sheet tube are provided to route the coolant in control of the rod vibration.

Abstract: An apparatus for sealing a joint between two substantially collinear tubes (12,14) is provided. Particularly useful for repairing a welded joint which has developed a crack (20) in the area of the weld (18), the apparatus provides a sleeve (26) which fits closely over the cracked joint. A housing (32), surrounding the sleeve (26), and a thrust ring (38) act to compress packing rings (28,30) against the sleeve to form a fluid-tight seal over the leaking joint. The sealing nut (40) maintains compression on the packing rings (28,30) when the installation apparatus (50,60,70) is removed. A method for installing the sealing apparatus is also disclosed herein.

Abstract: A long, thin strip of spring steel functions as the support base for one or more capillary tubes. The strip and its attached capillary tubes are thrust through a handhole in the side of a vessel containing a tube bundle and diverted by a guide into predetermined open lanes formed by the tubes of the bundle. The forward ends of the capillary tubes are directed downward for the jetting of fluid under high pressure into a body of sludge collected between the tubes and on the upper side of the tubes and their tube sheet. The source of the fluid is connected to the rear ends of the capillary tubes as the supply of fluid under high pressure.

Abstract: An apparatus for providing a high, positive locking force at the bottom of a nuclear fuel assembly to resist upward coolant flow forces. A latch on the fuel assembly alignment post is cammed to engage the fuel alignment pin in the core support stand and is linked to an actuating rod extending through the lower end of the fuel assembly center guide tube. The upward flow of coolant against the link and actuating rod causes the link to approach the horizontal, thereby exerting a high locking force between the latch and the fuel alignment pin. In the preferred embodiment spring means interact between the lower end fitting and the actuating rod to maintain an upward bias on the rod.