Abstract: An adjustable face milling cutter is carried on a turntable rotatable about a central axis that is coaxial with the cylindrical shell of the steam generator in which the tubesheet is located, to machine a circular path on the upper tubesheet surface. For complete circle-by-circle scanning of the tubesheet surface, the radius of the circular machined path is variable by virtue of mounting the milling cutter on the outer periphery of a circular mounting member turnable to different locked rotary positions about an off-center pivot axis on the turntable. The rotary support for the turntable is at its outer periphery, as provided by an encircling support ring which in turn is supported by a ball bearing assembly having an inner race secured to the turntable top and an outer race secured to the support ring top; teeth on the inner race being provided to accommodate a motor-operated drive gear.

Abstract: A servicing machine for a steam generator is accurately set up in the generator channel head with a pivoted arm mounted for rotation in a plane parallel to the tubesheet. The angular position of the arm, the longitudinal position of a carriage mounted on the arm and the vertical position of a platform on the carriage are remotely controlled to maneuver a probe used in mapping the precise location of the thousands of holes in the tubesheet. Various operations are then performed at each precise hole location by tools carried by the arm mounted carriage to prepare for installation of new tubing. The operation of a pair of remotely controlled pivoted arms, one on each side of the channel head divider plate, is coordinated to automatically position the ends of U-shaped tubes in corresponding holes in the tubesheet on opposite sides of the divider plate and to secure the same in place.

Abstract: An eddy current probe for mapping holes within a tube sheet of a steam generator, having a first coil (12) positioned at the top of the probe (10) with its axis coincident with the axis of the probe. A first coil pair (14 and 16) is arranged along a common axis perpendicular to the axis of the probe below the first coil (12) and is situated a distance from and on either side of the axis of the probe. A second pair of eddy current coils (18 and 20) is positioned along a common axis perpendicular to the axis of the probe and the axis of the first coil pair with the respective coils of the second pair located on either side of and spaced from the probe axis. Each of the respective coils are arranged to be separately excited by an alternating current source with the respective coil pairs coupled in opposition in corresponding balanced bridge arrangements.

Abstract: The segmented flexible hone comprises spirally wound high pressure tubing for conducting a lubricant therethrough with multiple bristled segments for contacting the inner surfaces of tubular holes so that contaminants and metal may be removed from the inner surfaces of the tubular holes. The bristled segments comprise compliant nylon bristles having enlarged abrasive globules attached to the outer end of the bristles in a non-flaking and a non-chipping manner. The bristled segments are separated by intervals along the high pressure tubing wherein no bristles are disposed but wherein the tubing has holes so that a lubricant mist may exit at high pressures and in a mist therefrom. The segmented flexible hone may be attached to a high pressure lubricant source and a mechanism for rotating the hone such that the ends of the bristles contact the inner surfaces of the members to be honed while a mist of lubricant is emitted from the holes in the high pressure tubing.

Abstract: A servicing machine for a steam generator is accurately set up in the generator channel head with a pivoted arm mounted for rotation in a plane parallel to the tubesheet. The angular position of the arm, the longitudinal position of a carriage mounted on the arm and the vertical position of a platform on the carriage are remotely controlled to maneuver a probe used in mapping the precise location of the thousands of holes in the tubesheet. Various operations are then performed at each precise hole location by tools carried by the arm mounted carriage to prepare for installation of new tubing. The operation of a pair of remotely controlled pivoted arms, one on each side of the channel head divider plate, is coordinated to automatically position the ends of U-shaped tubes in corresponding holes in the tubesheet on opposite sides of the divider plate and to secure the same in place.

Abstract: Apparatus that may be assembled inside the head of a steam generator and can perform various repair and inspection operations on the steam generator's tubes and tubesheet. Selective engagement of an included tool holder and associated tools with the tube and tubesheet is provided by a gear train which has a portion which houses a tool drive motor. The drive motor provides power to a tool holder-mounted tool chuck for driving the various tools insertable therein.

Abstract: The method of this invention involves abruptly applying a very high pressure pulse to the already pressurized annular space between a hydraulic expansion-swaging mandrel core and the tube being swaged to obtain a practically zero gap, after removal of the pressure, between the tube and the bore in which it is being swaged.

Abstract: A mandrel for hydraulically expanding tubes into engagement with a tubesheet, the body of the mandrel being coated with an electrically isolating impermeable membrane and having an eddy current coil adjacent the leading end thereof, the tube into which the mandrel is placed and the body of the mandrel serving as leads for operating the eddy current coil in order to determine when the leading end of the mandrel is adjacent the inner edge of the tubesheet and a mandrel having a portion formed from wire rope so that the mandrel is flexible and can fit into a tube adjacent a hemispherical head.

Abstract: Apparatus for baffling the flow of reactor coolant fluid into and about the core of a nuclear reactor. The apparatus includes a plurality of longitudinally aligned baffle plates with mating surfaces that allow longitudinal growth with temperature increases while alleviating both leakage through the aligned plates and stresses on the components supporting the plates.