Abstract: A tool positioning assembly for use inside a steam generator. A loading tool assembly removably attachable to a support base is used to insert the support base into the steam generator through a manway opening. The support base is removably attached to the steam generator at the manway. A retractable foot assembly pivotally attached to the support base stabilizes the support base inside the steam generator. A track assembly, removably attachable to the support base after removal of the loading tool assembly, receives an arm. A driven cogwheel on the waist of the manipulator engages a rack on the track assembly and support base for selectively driving and positioning the arm thereon. A tool coupling mounted on the arm is adapted to receive remotely controlled tools. The four degree-of-freedom movement of the arm provides access to all tubes in the tubesheet and allows mounting of tools outside the steam generator.

Abstract: A plug retainer for a tube plug. The plug head and inboard end of the plug are captured by a locking cup and cap screw. The locking cup is threadably engaged in the open end of the tube plug. The cap screw shank extends through a bore in the locking cup and is threadably engaged with the mandrel in the tube plug. Compression rings on the locking cup and cap screw seal the locking cup to the tube plug and the cap screw to the locking cup to prevent leakage. The locking cup is crimped on the cap screw by the use of flutes on the cap screw head.

Abstract: A rotating eddy current roller head for inspecting tubing. A main body portion has a set of whisker wheels rotatably attached thereto which center the main body portion in the tube. A roller housing slidably mounted on the main body portion for radial movement relative thereto is caused to track the surface of the tube by opposing magnets mounted in the main body portion and roller housing. An eddy current coil is mounted in a coil holder which is pivotally mounted in an offset manner at the exterior end of the roller housing. A spring mounted in the roller housing biases the trailing edge of the coil holder against the surface of the tube to maintain the eddy current coil at a constant distance from the surface of the tube during inspection procedures.

Abstract: A remotely installed, operated and removed manipulator for steam generator includes a mast, an articulating arm attached to the mast, capable of operating in the bottom or top head of a once through steam generator or the head of a recirculating steam generator. Each embodiment can be remotely installed and removed. The manipulator provides precise access to tubes and can sustain substantial loads, so the apparatus can perform much of the tube work that must be performed inside a steam generator.

Abstract: A lance assembly designed to clean sludge from the portion of the OTSG tube bundle which is inaccessible from the open tube lane. A track assembled between the OTSG outer shell and circular shroud around the tube bundle substantially opposite the open tube lane has a motorized carriage driven on the track which directs high pressure fluid through a plurality of nozzles toward the tube bundle through windows in the circular shroud. The nozzles are attached to a nozzle block which is capable of being moved vertically on the carriage to vary the flow impact area on the tube bundle.

Abstract: A surveillance assembly within a nuclear reactor contains representative reactor material specimens which are to be irradiated. The material specimens are contained within sealed capsules that are stacked end to end within a holder tube. Each capsule is designed with shaped end fittings which intermesh with the adjacent end of an abutting capsule, holder tube end plug or holder tube closure device. The capsules are restrained by axial loading imparted by the closure device. The holder tube is orthotropically supported within the reactor.

Abstract: A closure device for closing a tubular opening and releasably securing articles therein is disclosed. The device includes axially movable latching and actuator members which, respectively, engage the tubular opening and actuate or deactivate the latching means. Locking means are provided for releasably locking these members to prevent axial movements.