Abstract: A method is provided for removing radioactive internals structural members in the core of a reactor pressure vessel in a containment vessel. The method includes placing a first cask in a first internals assembly, detaching radioactive first internals structural members from second internals structural members in the first internals assembly, placing the detached first internals structural members in the first cask, placing the first internals assembly in a second cask, and removing the second cask containing the first internals assembly and containing the casked detached radioactive first internals members from the containment vessel. The first internal members may be radioactive baffle plates, and the second internals members may be former plates bolted to the radioactive baffle plates. Novel tooling, framework and fixtures facilitate disassembling, moving and storing the radioactive baffle plates.

Abstract: A method is provided for removing radioactive internals structural members in the core of a reactor pressure vessel in a containment vessel. The method includes placing a first cask in a first internals assembly, detaching radioactive first internals structural members from second internals structural members of the first internals assembly, placing the detached first internals structural members in the first cask, placing the first internals assembly in a second cask, and removing the second cask containing the first internals assembly and containing the casked detached radioactive first internals members from the containment vessel. The first internal members may be radioactive baffle plates, and the second internals members may be former plates bolted to the radioactive baffle plates. Novel tooling, framework and fixtures facilitate disassembling, moving and storing the radioactive baffle plates.

Abstract: An apparatus and method are provided for replacing the existing lower internal components in a nuclear reactor vessel with new components. The alignment of the new lower internals to the pressure vessel and the existing upper internals is achieved by customizing the new lower internals on-site based on alignment measurements obtained by gages installed on the new core barrel and the existing upper core plate. The gages allow the custom machining of radial support keys on the lower portion of the new core barrel and the custom drilling of upper core plate alignment pin holes in the new core barrel.

Abstract: A machining system for performing heavy duty milling and other repair operations under water is disclosed herein which is particularly useful in performing repair and maintenance operations in the core barrels of nuclear reactors. The machining system generally comprises a platform, a machining device which is detachably connectable to the platform which includes a drive motor and cutter necessary to effect the repair or maintenance operation, and a triaxial adjustment mechanism which permits the machine cutter to be precisely positioned at any desired location within the core barrel. The platform has a guide mechanism which includes both a rough and a fine guide means which precisely positions the machining device with respect to the platform when it is lowered thereon. A hydraulically operated lock remotely and detachably secures the machining device into position on the platform after the guide mechanism has properly positioned it.

Abstract: A machining system for performing heavy duty milling and other repair operations under water is disclosed herein which is particularly useful in performing repair and maintenance operations in the core barrels of nuclear reactors. The machining system generally comprises a platform, a machining device which is detachably connectable to the platform which includes a drive motor and cutter necessary to effect the repair or maintenance operation, and a triaxial adjustment mechanism which permits the machine cutter to be precisely positioned at any desired location within the core barrel. The platform has a guide mechanism which includes both a rough and a fine guide means which precisely positions the machining device with respect to the platform when it is lowered thereon. A hydraulically operated lock remotely and detachably secures the machining device into position on the platform after the guide mechanism has properly positioned it.

Abstract: A system and a method for removing and consolidating the spent fuel rods of a fuel assembly is disclosed herein. The system comprises a pushing assembly having a push rod for pushing a selected fuel rod out of a fuel assembly, a fuel assembly positioner including an elevator for conveniently positioning a fuel assembly within the spent fuel pool of a nuclear facility, a rod catching grid for preventing the pushed-out fuel rods from falling to the bottom of the pool and a transition cannister for funneling the rods into a consolidated arrangement within a storage cannister. In operation, the push rod is positioned over and engaged against the upper end of a fuel rod to be removed from the assembly. Thus engaged, the push rod is inserted through the cells in the grids of the fuel assembly that surround the selected fuel rod, thereby pushing it out of the fuel assembly. Thus the grid cells are used as an alignment means for the push rod during the rod-pushing operation.

Abstract: A system and a method for removing and consolidating the spent fuel rods of a fuel assembly is disclosed herein. The sytem comprises a pushing assembly having a push rod for pushing a selected fuel rod out of a fuel assembly, a fuel assembly positioner including an elevator for conveniently positioning a fuel assembly within the spent fuel pool of a nuclear facility, a rod catching grid for preventing the pushed-out fuel rods from falling to the bottom of the pool and a transition cannister for funneling the rods into a consolidated arrangement within a storage cannister. In operation, the push rod is positioned over and engaged against the upper end of a fuel rod to be removed from the assembly. Thus engaged, the push rod is inserted through the cells in the grids of the fuel assembly that surround the selected fuel rod, thereby pushing it out of the fuel assembly. Thus the grid cells are used as an alignment means for the push rod during the rod-pushing operation.

Abstract: Reversible fuel assembly grid tab repair tool having a tab bending member for remotely reforming fuel assembly grid tabs, wherein the tool has means for fine alignment of the tab bending member with the grid tab to be reformed. The grid tabs may be formed on the top and bottom edges of a grid strap which wraps a plurality of fuel rods disposed in the fuel assembly. The repair tool comprises a generally L-shaped frame having a vertical first leg and a horizontal second leg. Extending from the terminal end of the second leg is an alignment blade capable of being interposed between two fuel rods adjacent each side of the grid tab to be reformed. Attached to the top surface of the second leg at the terminus thereof is an anvil block having an anvil surface for bending the grid tab thereagainst when the grid tab is interposed between the anvil surface and the tab bending member.

Abstract: A replacement station includes an old split-pin-assembly (OSPA) removal stand and a new split-pin-assembly (NSPA) installation stand. The removal stand includes a saw and a drill. With the guide tube to which the OSPA is secured in the removal stand, the saw severs each OSPA below the flange which engages the base of the lower counterbore in the lower guide tube (LGT) separating the OSPA into a pin fragment and a second fragment including the flange and the remainder of the split-pin with the nut threaded into it. The second fragment remains secured to the LGT after the sawing operation. The guide tube is rotated so that the drill is coaxial with the shank of the pin of the second fragment. The second fragment is separated into a third fragment including the flange and a fourth fragment including the remainder of the pin and the nut both removable from the LGT. The installation stand has NSPA blades in which the new split pins are mounted. The LGT sans the OSPA's is positioned on the installation stand.

Abstract: A nozzle dam for providing a fluid-tight seal across a primary fluid nozzle in the plenum of a nuclear steam generating vessel includes an elongated shaft coupled at one end thereof to an anchor assembly frictionally engageable with the inner surface of the nozzle to anchor the dam in place and a fluid-impermeable seal apparatus coupled to the shaft and closing the nozzle and frictionally engageable with the inner surface thereof to form a fluid-tight seal. The seal apparatus includes a circular plate disposable in wedging frictional engagement with a frustoconical portion of the nozzle inner surface. The shaft extends through a central aperture in the plate and is threadedly engaged with a nut which holds the plate in place. The anchor assembly includes a foldable tripod arrangement coupled to the shaft in such a way that movement of the shaft toward the seal plate effects an increase in the frictional anchoring force. The seal assembly also includes an inflatable portion.

Abstract: Radial support of a tube support plate is provided by two associated members which also permit the position of the tube support plate to be adjusted with significantly improved ease. The apparatus comprises a jacking member which extends radially through the heat exchanger's inner shell and is in positive contact with its outer shell. A locking screw extends radially inward from the jacking screw and is in contact with the tube support plate. After this apparatus is used to centrally locate the tube support plate, it is welded together and to the inner shell.

Abstract: One or more pairs of vertically-spaced-apart sidewardly-aimable plasma arc cutting torches, the upper one angled upward and the bottom one downward, on the end of a horizontal boom movable longitudinally fore and aft and angularly sideward, are used to double-cut the tube bundle of a steam generator progressively in a manner clearing a path that accommodates torch assembly advancement.

Abstract: Cutting apparatus having spaced apart cutters which can be brought closer together are disposed on one end of a boom which is movable in a plane transverse to the longitudinal axis of a closely packed tube bundle to cut out short segments from the tubes starting at the periphery and working through the tube bundle by bringing the cutters closer together to provide clearance as the cutters move deeper into the tube bundle.