Abstract: A control rod drive replacement device includes a channel for mounting on a support under a nuclear reactor pressure vessel and a control rod drive extractor removably received in the channel. The control rod drive extractor includes a base and a housing pivotably connected to the base. The housing is configured for receiving a control rod drive. The base includes a base axis. The housing is pivotably attached to the base at the base axis for pivoting between a horizontal orientation in which the housing is aligned within the channel and a vertical orientation in which the housing is aligned for receiving the control rod drive from the nuclear reactor pressure vessel. The housing is vertically movable with respect to the base in the vertical orientation.

Abstract: A control rod drive replacement device is provided.

Abstract: An improved manipulator system having a remotely actuated tube walker assembly for reciprocally moving the manipulator along a tube bundle for inspection and repair of the tubes of the tube bundle wherein the tube walker has a movable inner section and an outboard section with both sections having groups of hydraulically actuated locking fingers which are selectively engageable with the tubes of the tube bundle so that when the fingers of the outboard section are locked the fingers of the inner section are disengaged and the inner portion can be moved axially to an aligned position with new tube locations.

Abstract: The present invention comprises an improved manipulator system having a remotely actuated tube walker assembly for reciprocally moving the manipulator along a tube bundle for inspection and repair of the tubes of the tube bundle wherein the tube walker has a movable inner section and an outboard section with both sections having groups of hydraulically actuated locking fingers which are selectively engageable with the tubes of the tube bundle so that when the fingers of the outboard section are locked the fingers of the inner section are disengaged and the inner portion can be moved axially to an aligned position with new tube locations.

Abstract: A system for delivering tooling around the annulus of a steam generator without damaging any part of the steam generator is provided where the tooling delivery device travels between the tube bundle and the vessel shell and delivers tooling for cleaning, inspection, retrieval and repair. The device has various types of locomotion system including treads, rollers, magnets and vacuum. The cleaning device has multiple high pressure nozzles that rotate 180 degrees about a horizontal axis and 360 degrees about a vertical axis enabling the device to sweep multiple lanes of tubes simultaneously and also clean the front and back of the annulus floor and tube sheet.

Abstract: A method of removing rib plugs from steam generator tubes in energy producing units such as nuclear reactors includes the removal of the expander element or mandrel from the expanded part of the rib plug, TIG welding a bead on the available internal surface of the plug in a spiral manner from the bottom to the top thereof to relax the rib plug from its forced contact with the tube and removal of the rib plug as a unit from the tube after it has cooled down from the welding process.