Westinghouse Electric Corporation

The United States of America As Represented by the United States

Westinghouse Electric Company LLC

Robert E Meuschke

Leonard P Hornak

James R Marshall

Louis J Malandra

Bruce W Bevilacqua

David John Stefko

Edward P Shields

James E Gillett

Stephen N Tower

Frank I Bauer

Donald G Sherwood

Thomas G Bengel

Harry N Andrews

Robert B Salton

Edward H Smith

Phillip E Miller

David E Boyle

Donald L Wolfe

Bernard L Silverblatt

Walter E Desmarchais

Charles H Boyd

Anthony A Massaro, Jr

Robert W Beer

Gregory E Mazza

Alex W Harkness

Leonard R Katz

Robert M Blumstein

Daniel M Trombola

Jose M Martinez

Paul P Pomaibo

Walter J Vandriak

Moshe A Mahlab

Joseph R Schulties

Raman G Patel

Edward J Rusnica, Sr

John A Klimek

William J Smoody

Mark J Harper

Adelbert E Satterlee

An apparatus and method are provided for inverting the lower internal assembly of a nuclear reactor. The apparatus includes a frame which is sized to receive the lower internal assembly. The frame supports the lower internal assembly as it is being inverted. The apparatus also includes a spider assembly which fits within the lower internal assembly and provides support for a baffle assembly located therein. The method includes the steps of removing the lower internal assembly from a reactor vessel and rotating the lower internal assembly prior to performing maintenance.

Lower reactor internals up-ending device

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

A refueling machine for refueling a pressurized water reactor has a trolley which travels on rails mounted on a transversely movable bridge. The trolley supports a refueling mast which includes an outer mast and two horizontally spaced apart, vertically movable gripper masts disposed within the outer mast. This design permits the machine to safely handle two fuel assemblies simultaneously in order to substantially reduce refueling critical path time. The two gripper masts can be raised, lowered and otherwise operated independently of each other. A partition plate extending through the stationary mast between the two movable gripper masts permits each fuel assembly held in the refueling mast to be independently leak tested.

Refueling machine

An apparatus, which reinforces a shroud that is contained within a reactor vessel, is operable for reinforcement of the shroud in the event of cracking in the shroud. The apparatus comprises a reactor wall positioned surrounding the shroud. A beam is attached to and extends generally axially on the shroud for absorbing the forces generated by the cracking in the shroud, and a radial support is positioned between the beam and the wall of the reactor vessel for transmitting any forces absorbed by the beam to the wall.

Apparatus for reinforcing a reactor vessel core shroud

A jet pump assembly for recirculating coolant through a recirculation loop of a boiling water reactor vessel, the jet pump assembly comprises a jet pump in operative association with the recirculation loop for forcing the coolant through the recirculation loop. A beam is positioned adjacent and in operative association with the jet pump for assisting in maintaining the positional relationship of the jet pump. A bolt is inserted in the beam for resisting the hydraulic forces generated in the jet pump, and an insert is disposed in said beam for receiving and surrounding the bolt which, in turn, reduces stress on the beam.

Jet pump assembly for recirculating coolant through a recirculation loop

A tank is disclosed for containing a liquid in which control rod drive shafts of a nuclear power plant are stored. The tank comprises a lower tank portion having a bottom and a tank wall extending outwardly from the bottom for defining a lower storage cavity of the tank. An upper tank portion having walls is removably attached to the lower tank portion for defining an upper storage cavity of the tank. A plurality of tubes are arranged in the lower tank portion for adaptably receiving the shafts for storage.

Apparatus for storing control drive rod shafts during chemical

A method of refueling a nuclear reactor whereby the drive mechanism is disengaged and removed by activating a jacking mechanism that raises the closure head. The area between the barrier plate and closure head is exhausted through the closure head penetrations. The closure head, upper drive mechanism, and bellows seal are lifted away and transported to a safe area. The barrier plate acts as the primary boundary and each drive and control rod penetration has an elastomer seal preventing excessive tritium gases from escaping. The individual instrumentation plugs are disengaged allowing the corresponding fuel assembly to be sealed and replaced.

Reactor refueling containment system

A cabling arrangement is provided for a nuclear reactor located within a containment. Structure inside the containment is characterized by a wall having a near side surrounding the reactor vessel defining a cavity, an operating deck outside the cavity, a sub-space below the deck and on a far side of the wall spaced from the near side, and an operating area above the deck. The arrangement includes a movable frame supporting a plurality of cables extending through the frame, each connectable at a first end to a head package on the reactor vessel and each having a second end located in the sub-space. The frame is movable, with the cables, between a first position during normal operation of the reactor when the cables are connected to the head package, located outside the sub-space proximate the head package, and a second position during refueling when the cables are disconnected from the head package, located in the sub-space. In a preferred embodiment, the frame straddles the top of the wall in a substantially horizontal orientation in the first position, pivots about an end distal from the head package to a substantially vertically oriented intermediate position, and is guided, while remaining about vertically oriented, along a track in the sub-space to the second position.

Integrated head package cable carrier for a nuclear power plant

A nuclear reactor such as a pressurized water reactor has an integrated head package providing structural support and increasing shielding leading toward the vessel head. A reactor vessel head engages the reactor vessel, and a control rod guide mechanism over the vessel head raises and lowers control rods in certain of the thimble tubes, traversing penetrations in the reactor vessel head, and being coupled to the control rods. An instrumentation tube structure includes instrumentation tubes with sensors movable into certain thimble tubes disposed in the fuel assemblies. Couplings for the sensors also traverse penetrations in the reactor vessel head. A shroud is attached over the reactor vessel head and encloses the control rod guide mechanism and at least a portion of the instrumentation tubes when retracted. The shroud forms a structural element of sufficient strength to support the vessel head, the control rod guide mechanism and the instrumentation tube structure, and includes radiation shielding material for limiting passage of radiation from retracted instrumentation tubes. The shroud is thicker at the bottom adjacent the vessel head, where the more irradiated lower ends of retracted sensors reside. The vessel head, shroud and contents thus can be removed from the reactor as a unit and rested safely and securely on a support.

Integrated head package for top mounted nuclear instrumentation

A preferred embodiment of the present invention provides an incore instrumentation system for detecting conditions, e.g., neutron flux density, within the core of a pressurized water nuclear reactor (PWR). The instrumentation system includes a plurality of long straight thimbles (52), containing fixed incore detectors, which are inserted through the top closure head (18) of the PWR. The invention meets today's principal utility, EPRI, DOE and NRC requirements and preferences, including no bottom RV head penetrations and the use of fixed incore instrumentation. In addition, an instrumentation system according to the invention is mechanically simple with a straight core insertion/removal path that does not conflict with or add significant complexity to the reactor internals.

Incore instrumentation system for a pressurized water reactor

A transfer system moves fuel assemblies along a track extending through a transfer tube within a containment wall in a nuclear power plant between the auxiliary building side and the containment building side. A car carries a basket for the assemblies. Two winches are located on the auxiliary building side above the water level existing over the track during refueling operations. The winches operate respective pairs of cables, driving the car in either direction. Four sheaves respectively direct the cables to the horizontal direction along the track. One pair of cables is secured to a yoke on the car to drive the car away from the containment building. Two horizontal sheaves are located near the containment end of the transfer tube. The other two cables extend horizontally along the track from the vertical sheaves to the horizontal sheaves, redirecting them to extend horizontally in the reverse direction. These return cables are secured to the yoke to drive the car toward the containment building. The winches are operated under the control of a programmable limit switch to move the car selectively between one end position in which the car is within the auxiliary building, and the other end position in which the car is principally within the containment building with at least the car yoke located over the track within the transfer tube and to the auxiliary building side of the horizontal sheaves.

Dual winch nuclear fuel transfer system providing more reliable fuel

A method for installing a heater unit assembly (52, 54) in a reactor pressure vessel (2) for performance of an annealing treatment on the vessel (2), the vessel (2) having a vertical axis, being open at the top, being provided at the top with a flange (6) having a horizontal surface, and being provided internally, at a location below the flange (6), with orientation elements (8) which are asymmetrical with respect to the vertical axis, by the steps of:

Heating equipment installation system

A straightening device (16) for bent fuel assembly alignment pins (12) in an upper core plate (10) comprises elongatged mast (22) haivng an upper and lower portion, bail (25) secured to the upper portion and cross member (28) secured to the lower portion. At one end of the cross member (28) is attached pin straightening assembly (19), the other end having counterweight (31) to assure a horizontal orientation of the cross member (28). Pin straightening assembly (19) is further comprised of housing (37) having wedge-shaped adjustable shim (61) connected to its top surface, the housing (37) secured to the cross member (28) by baseplate (34). Four axially compressible and laterally deformable compression springs (41) are connected between baseplate (34) and housing (37) to provide angular and translational compliance for housing (37). Housing (37) has two vertical holes disposed therein, first hole (50) adapted to receive hardened die insert (54) having bore (55 ) with frusto-conical opening (56) for receiving bent pin (12), and second hole (51) for receiving another pin (14). Connected to baseplate (34) opposite housing (37) is hydraulic ram (44) for moving housing (37) into full planar contact with bottom surface (47) of upper core plate (10) to effectuate the straightening of bent pin (12).

Fuel assembly alignment pin straightening method

A method for limiting movement of a thermal shield of a nuclear reactor, and a thermal shield displacement limiter therefor, is provided where at least four and preferably six or more key-way inserts are positioned in pockets machined in the upper portion of a thermal shield, and bolted and doweled to the thermal shield. Each key-way insert is engaged by a limiter key that is bolted and doweled to the core barrel to tangentially restrain movement of the thermal shield relative to the core barrel, while allowing radial and axial movement to the thermal shield relative to the core barrel. Preferably, lock pins extend diametrically through the bolts and dial pins and engage the key-way insert and limiter key, respectively, to lock the bolts and dowels in position, and the engaging surfaces between the key-way inserts and the limiter keys are wear hardened.

Method for limiting movement of a thermal shield for a nuclear reactor,

A thimble grip fuel assembly handling tool (20) for transporting fully loaded fuel assemblies (52) is disclosed. The tool (20) comprises an elongated mast (23) slidingly disposed within an elongated cylinder (113), the cylinder being of a length less than the mast (23) such that the tool defines a mast fill-up position (126) and a mast full-down position (128). A cage (110) assembly acts to protect the gripping means (32) when the tool is transported in the mast full-up position (126). The gripping means (32) is comprised of a plurality of gripping members (49) which grip the inside diameter of control rod guide thimbles (50). The load path is distributed in the tool such that when the fuel assembly (52) secured to the gripping means (32) is raised, the weight of the fully loaded fuel assembly (52) acts to increase the gripping force on the fuel assembly. A number of indicators on the tool act to indicate to an operator: when the tool is in the mast full-down position; when the gripping members (49) have been fully actuated; and if there is any slipping of the gripping members within the fuel assemblies. The tool also includes a secondary gripping mechanism which engages the top nozzle of the fuel assembly.

Growing community of inventors

Monroeville, PA, United States of America

Robert E Meuschke