Westinghouse Electric Corporation

Edward H Smith

Arthur W Kramer

Robert Shaffer

Richard L Stiller

Robert E Meuschke

Robert Draper

William E Pirl

Ralph W Tolino

Kenneth S Gerkey

David John Stefko

Charles H Roth, Jr

Jeffrey E Hydeman

Thomas H Dent

Regis R Vollmer

Robert M Blumstein

Robert T Marchese

Robert E Dunn

Stephanie M Havoic-Conroy

Rodney A Lutz

John J Anderson

John A Klimek

William J Smoody

A camera mast system permits remote inspection of nuclear fuel assemblies and other components of nuclear reactors. The system includes a camera mast assembly mounted on a refueling mast which may be positioned over a selected fuel assembly in the reactor core. An extendable camera mast having a camera mounted thereon moves vertically with respect to a stationary camera mast and the refueling mast in order to allow for visual inspection of various components in the reactor core. The camera mast assembly preferably includes a video cable take-up mechanism for handling the camera video cable as the extendable camera mast is moved up and down. The camera mast assembly is preferably removably mounted on the refueling mast in order to aid in installation and removal. The removable mounting also allows the camera mast assembly to be used independently of the refueling mast. The camera mast assembly may optionally include an extendable fuel assembly guide mast including a guide member which facilitates placement of fuel assemblies within the reactor core. The extendable guide mast is preferably rotatably mounted on the refueling mast. In another embodiment, a guide mast assembly is mounted on the refueling mast, including an extendable guide mast having a fuel assembly guide member mounted thereon for aligning the fuel assemblies in the reactor core.

Nuclear reactor camera mast assembly and loading guide

Both a system and method are provided for laser welding the inner walls of conduits, such as the sleeves used to repair the heat exchanger tubes of nuclear steam generators. The system generally comprises an elongated tubular housing, a fiber-optic cable for conducting remotely generated laser light into the tubular housing, a beam deflection mechanism supported within the distal end of the tubular housing and including a rotating mirror for radially reflecting and focusing light received from the fiber-optic cable around the inner wall of the sleeve, and a tracking assembly mounted on the distal end of the tubular housing for maintaining a constant radial distance between the mirror of the beam deflection mechanism and the inner wall of the sleeve despite any irregularities which may be present in the roundness of the sleeve. The tracking assembly includes at least one roller which is resiliently mounted in the tubular housing of the system behind the front portion of the mirror of the beam deflection mechanism. To facilitate mirror replacement, the distal end of the tubular housing is easily removable. To ensure reliable rotation of movement, an electric motor and gear train is mounted in the proximal end of the tubular housing. Finally, the fiber-optic cable that extends through the proximal end of the tubular housing is configured to traverse the electric motor and drive train with a single S bend in order to maintain a high light transmission efficiency through the cable.

System and method for laser welding the inner surface of a tube

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. The platform is advantageously designed to be secured onto a component within the core barrel having a known and precise alignment with respect to the other core barrel components, such as the support lugs of the thermal shield, which in turn provides a mechanical reference point for the machine cutter attached to the platform.

Method for using an underwater milling machine

A control road guide tube inspection system is provided which consists of a camera delivery tool which is lowered through the 2.3 inch diameter opening in the guide plates of the tube to position a camera over a selected hole in the guide plate to be inspected. The camera is an underwater CCTV camera, and the system further includes an image enhancement system which uses the video output from the camera to obtain quantitative data on the wear of the guide plates. An ultrasonic gauge to measure the distance from the camera to the guide plate being inspected is also provided on the delivery tool. Once the delivery tool is inserted into the central opening of the guide tube, two mechanisms are used to position the camera over the guide plate holes, including a foot element which is pivoted out of the confines of the housing tube, allowing the delivery tool to rest on the guide plate which is immediately below the guide plate to be inspected by the camera and a straight line motion linkage which moves the camera sideways out of the confines of the housing tube enabling the camera to look straight down at the holes formed in the guide plate. Because the guide plates are evenly spaced in the guide tube, by resting the delivery tool on the guide plate below the one to be inspected, the camera will be positioned a known fixed distance from the guide plate to be inspected.

Control rod guide tube inspection system

Underwater milling machine system for core barrel repair

A light-weight, portable, pipe crawler vehicle includes a four-wheeled chassis, with the sets of wheels along the opposite sides of the chassis being respectively driven by two hydraulic motors. A foldable mast is removably pivotally mounted on the chassis and carries a pneumatic cylinder which, when the mast is in its erected position, forces bearing wheels against the opposite side of the pipe to force the chassis wheels into firm frictional engagement with the pipe so that it can traverse vertical pipe sections while remaining under control. The dimensions of the vehicle are such that when the mast is folded the vehicle will fit through a 16'-diameter manway of a nuclear steam generator vessel. The chassis also carries a three-axis remote manipulator and one or two remotely-controlled video cameras. A position indicator including a star wheel and proximity sensor is disposed for rolling engagement with the pipe to sense distance travelled.

Portable and collapsible pipe crawler

An improved model steam generator for simulating the conditions within a nuclear steam generator in order to monitor the condition of the heat exchange tubes and tubesheet of the nuclear steam generator is disclosed herein. The improved model steam generator includes a highly effective separator assembly for separating water droplets entrained within the steam flowing out of the outlet of the secondary side of the generator formed from a plurality of separator grids, each of which includes an array of semi-cylindrical deflector members. The grids are vertically stacked with the deflector members transversely disposed to the flow of steam generated by the model steam generator. Each of the parallel arrays of deflector members in each grid is angularly disposed approximately 45.degree. to the deflector members in the grids above it and below in order to provide a tortuous path for the flow of steam ascending therethrough. The separator assembly removes proportionately more water droplets from the steam generated by the model steam generator, which in turn allows it to accurately simulate the sludge accumulation characteristics of the nuclear steam generator being monitored. The model steam generator also includes a bankable condenser assembly which greatly enhances its turn-down ratio, as well as a feedwater pre-heater which allows it to accurately simulate the thermohydraulic conditions at a variety of points on the tubesheet of the nuclear steam generator.

Model steam generator

The decontamination apparatus comprises a rotatable hone capable of being inserted into a heat exchange tube of a steam generator for removing contamination from the inside of the heat exchange tubes. The apparatus also comprises means for advancing and retracting the hone and means for removing contamination from the apparatus as the apparatus is withdrawn from the steam generator.

Decontamination apparatus

An apparatus for actuating a tube guide expander device inserted in a tube end and extracting it therefrom subsequent to tube expansion induced by guide-expander actuation. The apparatus includes inner and outer sleeve structures which are independently axially displaceable relative to the tube and guide-expander. The outer sleeve structure is engageable with a first compression structure of the device to secure it and its engaged tube in place during relative axial displacement of a second compression structure of the device. Selectively coupling the inner sleeve structure to the device's second compression structure and axial displacement of both axially compresses a radial expansion element situated between the compression structures and expands the enclosing tube. A series of balls are radially displaceable from an outer unobstructing position through radial openings in the inner sleeve structure and an intermediate sleeve structure to an inner obstructing position protruding into the inner sleeve structure's bore so as to axially engage a portion of the second compression structure and prevent its extraction from the bore during axial displacement of the inner sleeve structure. Radial displacement of the balls is provided by selective axial displacement of the intermediate sleeve structure arranged about the inner sleeve structure. Simultaneous axial displacement of the inner and outer sleeve structures away from the tube with the balls in obstructing position subsequent to the tube's expansion enables extraction of the guide-expander from the tube.

Apparatus for actuating and extracting a tube guide-expander

A tool support arm 22 is mounted to a plate member 18 which in turn is mounted to a horizontal rotatable table 16. The plate 18 has, on its upper face, a plurality of horizontally extending tool support sleeves 20, each sleeve cooperating with one of the horizontally extending tool support arms for secure engagement and quick release therebetween. The sleeve includes means 40, 48 for indexing the tool arm therein. The tool support arms are intermediately hinged 28 for pivotal movement in a vertical plane to lower the vertical projecting tool supported thereon to a non-interfering inactive position while the active tool on another tool support arm extending horizontally from the plate is in the active, raised position.

Tool supporting arm and mounting plate with a plurality of quick

A method for inserting a tube through a tubesheet aperture and expanding it into contact with the aperture's wall. A tube guide-expander device is assembled in an open end of a tube with a portion of the device protruding from the tube. The guide-expander includes a distally protruding tip portion tapered to diverge in a direction toward the tube so as to facilitate insertion of the guide-expander and engaged tube through apertures in spatially separated tube supports and tubesheet. The guide-expander and tube engaged therewith are axially displaced relative to the tubesheet until the desired relative configuration is obtained. Expansion of the tube results from expanding the assembled tube guide-expander and driving the housing tube in the radial direction against the tubesheet aperture's wall. Such guide-expander expansion obtains from relatively axially displacing two structural components and compressing an interposed, radially expansible structure.

Method for installing a tube in a heat exchanger tube sheet

An accurately indexed rotatable tool positioning table for use with inspection and repair apparatus remotely disposed within the channel head of a steam generator is shown. The table is automatically rotated by a motor to predetermined positions and an angular position resolving mechanism in engagement therewith provides an output signal responsive to the angular movement for accurate position determination and control. An indexing pin is received in an indexing bushing in the plate to insure accurate, repeatable positioning of the plate, and switch means are associated therewith and operatively connected to the tool energizing circuit to prevent operation of any tool until the indexing pin is properly seated in the bushing and to prevent the positioning motor actuation until the pin is fully withdrawn from the bushing.

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Brave, PA, United States of America

Edward H Smith