Westinghouse Electric Corporation

Thomas E Arzenti

William E Pirl

Warren R Junker

Michael J Metala

William G Clark, Jr

Bruce W Bevilacqua

Lee W Burtner

Robert P Vestovich

Harold P Johnson

Annette M Costlow

Robert D Senger

Both an apparatus and a method for simultaneously inspecting the walls of a tube with both ultrasonic and eddy current probes is disclosed herein. The apparatus generally comprises a cylindrical housing assembly insertable within the tube to be inspected, and a probe carrier rotatably mounted within and helically movable with respect to the housing. The probe carrier holds three ultrasonic probes for transmitting ultrasonic beams which are directly oriented radially, chordally, and axially with resepect to the longitudinal axis of the tube, as well as an eddy current probe for simultaneously inspecting the walls of the tube with electromagnetic lines of flux. The apparatus further includes a helical drive train formed from a lead screw assembly having a motor means, a drive shaft, and a drive sleeve for imparting a helical scanning motion to the probe carrier with respect to the housing. The interior of the drive sleeve is slidably engaged to the shaft which is in turn coupled to the output of the motor, while the outside of the drive sleeve is threadedly engaged to the interior of the housing. The probe carrier is in turn coupled to the drive sleeve. In the method of the invention, the data generated by the three eddy current probes is correlated with the data generated by the eddy current probe for each specific section of the tube, and displayed simultaneously to the system operator. The resulting complementary display of both ultrasonic and eddy current probe information allows the system operator to accurately determine the size, shape and nature of any flaws which may be present in the walls of the tube.

Apparatus and method for providing a combined ultrasonic and eddy

A flexible hardrolling mandrel for expanding a sleeve within a tube of a nuclear steam generator is disclosed herein. The flexibility of the tool facilitates the insertion of the tool into tubes of the nuclear steam generator that have only a limited accessibility, and the tool is designed to transfer sufficient torque as required for hardrolling by way of the flexible design. Generally, the hardroll mandrel assembly includes an elongate housing with flex joints along its length, a roller cage rotatably mounted to the housing supporting at least one roller, a tapered actuator shaft slidable within the roller cage to extend the roller, a flexible inner shaft connected to the actuator shaft and drivingly connected to the housing near the roller cage, and an end effector and drive device for imparting torque to the housing. The driving torque is then transferred from the housing to the flexible inner shaft at the end thereof to drive the tapered actuator shaft, thereby providing the required hardrolling torque and minimizing the torque losses associated with flexible drive shafts.

Flexible hardroll mandrel assembly for sleeving peripherally located

Both an apparatus and a method for simultaneously inspecting the walls of a tube with both ultrasonic and eddy current probes is disclosed herein. The apparatus generally comprises a cylindrical housing assembly insertable within the tube to be inspected, and a probe carrier rotatably mounted within and helically movable with respect to the housing. The probe carrier holds three ultrasonic probes for transmitting ultrasonic beams which are directly oriented radially, chordally, an axially with respect to the longitudinal axis of the tube, as well as an eddy current probe for simultaneously inspecting the walls of the tube with electromagnetic lines of flux. The apparatus further includes a helical drive train formed from a lead screw assembly having a motor means, a drive shaft, and a drive sleeve for imparting a helical scanning motion to the probe carrier with respect to the housing. The interior of the drive sleeve is slidably engaged to the shaft which is in turn coupled to the output of the motor, while the outside of the drive sleeve is threadedly engaged to the interior of the housing. The probe carrier is in turn coupled to the drive sleeve. In the method of the invention, the data generated by the three eddy current probes is correlated with the data generated by the eddy current probe for each specific section of the tube, and displayed simultaneously to the system operator. The resulting complementary display of both ultrasonic and eddy current probe information allows the system operator to accurately determine the size, shape and nature of any flaws which may be present in the walls of the tube.

An apparatus and method for remotely inserting and positioning a sleeve-loaded mandrel within a damaged tube mounted in the tubesheet of a nuclear steam generator is disclosed herein. The apparatus of the invention generally comprises a frame, a mounting mechanism for detachably and pivotally mounting the frame to the open end of one of a first tube in the tubesheet, an advancing assembly supported by the frame for remotely inserting and advancing the sleeve-loaded mandrel to a position across a damaged section of the selected tube, and a drive train for pivotally positioning the advancing assembly into alignment with the open end of the selected tube. In the preferred embodiment, the advancing means is formed from the pair of hydraulically operated grippers, one of which is reciprocably movable with respect to the other. Additionally, the mounting mechanism inlcudes a double-action hydraulic cylinder that is capable of translating the frame into engagement with the tubesheet after the advancing assembly has been pivoted into alignment with the damaged tube. In the method of the invention, the first tube is chosen so that the advancement assembly may be pivoted into position under two or more tubes that need to be sleeved.

Apparatus and method for simultaneously loading a reinforcing sleeve and

A tool for inserting sleeve blanks in damaged steam-generator tubes of light weight capable of being manipulated by ROSA, a remotely operated service arm. ROSA permits the tool to be attached externally of the channel head of the steam generator. The tool includes a fixed gripper and a moveable gripper. The gripping member of each gripper is a flexible sheet or bladder which conforms readily to the surface being engaged. For insertion, the sleeve blank is mounted on a mandrel. The insertion is carried out by operating the grippers repeatedly through the following cycle until the sleeve blank is inserted into the damaged tube:

Sleeving of steam generators

A gripper assembly whose gripping member is a thin (0.050' to 0.060') pliable elastometer, typically of a Pelethane compound having high coefficient of friction with respect to the surface to be gripped. The assembly includes a hollow retainer formed of abutting retainer sections. Internally the sections form a circularly cylindrical surface. The gripping member is circularly cylindrical and is mounted on the retainer so that it extends over the internal cylindrical surface. The ends of the gripping member have rings which are sealed pressure-tight in slots in the end surfaces of the retainer. Within the gripping member there is a cage formed of rods joined by rings for centering an object to be gripped by windows and defined between the rods and rings of the cage. The retainer has a port through which a fluid (air) under pressure is injected. The retainer has a slot connected to the port so that the fluid is distributed over the region between the gripping member and the internal surface of the retainer causing the gripping member to exert pressure on the object to be gripped.

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Munhall, PA, United States of America

Thomas E Arzenti