General Electric Company

Global Nuclear Fuel - Americas, LLC

William C Peters

David Grey Smith

Edward G Apple

William B Gaylord, Jr

Lon Paulson

Roger Evan Strine

David O Sheppard

Harold B King

John L Harmon

Robert A Haughton

Charles Frederick Laing

Donald F Butzin

Andrew A Lingenfelter

Robert K Williams

John Taylor

Charles F Lang

Various geometric constructs are configured for use in modeling a system, for example a fissile system, using an analysis method, such as Monte Carlo, to model such systems based upon the interstitial regions formed by these geometric constructs. The various geometric constructs are configured to provide for modeling of, for example, complex arrays and lattices and allows for embedding of these constructs and virtual filling of arrays of these modeled units.

Methods of using geometric constructs for neutronics modeling

An end support system is applied to each end of a container for shipping nuclear fuel assemblies in an inner box within the container. The end support system includes a rectilinear metal end frame, a crosspiece with a reinforcing channel along an inside surface of the crosspiece and four arms projecting in a perpendicular direction from the metal end frame for straddling the sides of the container end. By screwing the metal end support system into the wooden framing elements of the container, the integrity of the container ends is maintained during hypothetical accident conditions specified in licensing regulations.

End support system for a shipping container for nuclear fuel

Water rod segments are provided in a nuclear fuel bundle and releasably connected one to the other at joints within openings through the spacers. A lowermost water rod segment passes through a number of the spacers, with water rods segments above the lowermost segment being screwthreaded one to the other forming joints therebetween within the spacer openings. Capture flanges are provided immediately above and below the spacers on each of the segments such that the spacer is captured between adjoining segments. Interior passages through the segments communicate water along the water rod to an upper region of the fuel bundle. Swirler vanes are disposed about the water rod segments and terminal ends of the swirler vanes may form the capture flanges, retaining the spacer between adjacent segments.

Nuclear fuel bundle having spacers captured by a water rod

The shipping container includes an outer container body, an inner containment vessel housing a pair of superposed product pails and a self-extinguishing fire-retardant foam insulation layer between the outer container and inner vessel. The inner vessel includes a gusseted upper flange and a lid bolted to the flange with a sealing gasket therebetween. Upper and lower dunnages are provided at the upper and lower ends of the outer container. The upper dunnage includes ceramic fiberboard panels and foam material straddled by steel sheets and additional ceramic fiberboard panel to separate the lid of the vessel and the top of the container. The top is secured to the outer container body by bolts passing through the top and internally into tapped bolt brackets along an interior wall of the outer container body. A retaining ring secures the arcuate overlying rolled edge of the top about the beaded rim of the outer container body. A reinforced plate covers the seam of the outer container underneath the retaining ring bolt for additional container integrity. Vent holes with plastic plugs which melt in response to a predetermined temperature vent the container body to preclude pressure buildup within the container body by expanding gases.

Shipping container for radioactive materials and methods of fabrication

An adjustment tool is provided, having a probe, a head, an arm and a micrometer attached to the head. With the probe inserted into a spacer cell opening, the micrometer handle is rotated to a predetermined setting to pivot the arm. The opposite end of the arm from its engagement with the micrometer drive head engages and displaces the spring of the spacer cell to adjust its spring force. In one form, the arm is housed within the probe and the micrometer drive head displaces the distal end of the arm outwardly to correspondingly displace the spring outwardly, thereby decreasing the spring force. In another form of the spacer tool, the arm is spaced from the probe and has pivotal contact surfaces to straddle the spring. Movement of the drive head by rotating the micrometer handle to a predetermined setting causes the spring to be displaced inwardly of the spacer cell opening to increase the spacer spring force.

Spacer spring force adjustment tool and method of adjusting the spacer spring force

A tool kit for adjusting the angular orientation of water rods about respective axes in a nuclear fuel bundle includes a washer wrench, socket, orientator wrenches, orientator gauges and an orientator cap. The washer wrench has opposed jaws having parallel surfaces and reliefs at junctures between the surfaces and the base of the jaws to inhibit rounding off corners of tie bars connected to the water rods. The socket has a corresponding D-shaped recess as the tie bar ends to facilitate rotational adjustment thereof. Orientator wrenches have witness notches for aligning the flats of the tie bars. The orientator gauges comprise a series of gauge bodies each having a pair of axially parallel openings with stepped margins to the openings such that one opening is axially offset from the margin defining the entrance to the other opening. The orientator cap has complementary-shaped openings for receiving the upper ends of the tie bars to maintain the orientation of the tie bars and water rods during shipment of the fuel bundle.

Tool kit for fabricating, inspecting and handling a nuclear fuel bundle

The extraction tool includes an inner rod pivotally mounting at its distal end a pair of collet sections having mechanical clamping jaws. An outer tube may be advanced and retracted axially relative to the inner rod by a locking tube nut threaded on a sleeve forming part of the inner rod. The inner rod and outer tube are non-rotationally engaged with one another. By axially displacing the outer tube relative to the inner rod, the collet sections are movable between collet-open and closed positions such that the jaws of the collet can respectively grasp and release the barbed end of the end plug of the fuel rod.

Tool for retracting fuel rods from and inserting fuel rods into a nuclear fuel assembly and methods therefor

A guide assembly is seated at the upper end of a channel for a nuclear fuel bundle. The guide assembly includes a lower guide plate with an opening corresponding in dimension to the dimension of the spacers of the fuel bundle to be inserted. The lower guide plate mounts depending locators to locate the guide apparatus on the channel. An upper guide plate spaced above the lower guide plate mounts rollers spaced from the lower guide plate a distance corresponding to the distance between the first and second spacers of the fuel bundle. The fuel bundle is lowered through the guide apparatus by engagement of the spacers with the rollers and in the channel opening to ensure the fuel bundle is guided into the channel without damage to either.

Methods for guiding a fuel bundle into a channel

The spacer envelope measurement system includes a generally U-shaped fixture having support plates extensible into positions overlying the spacer for supporting the fixture from the spacer. Extensible heads are carried by the fixture for engaging the spacer, followed by the heads of measurement gauges whereby, upon extending the heads into clamping engagement with the spacer along opposite sides thereof, the measurement gauges accurately determine the lateral dimensions of the irradiated spacer. A spacer bar clamp member is pivotal between positions opening the fixture opposite the base leg of the U-shaped fixture, enabling the bundle to reside within the U-shaped opening and a second position closing the opening for aligning the fixture and the bundle. The measurements are taken under water in a nuclear fuel service pool.

Nuclear fuel bundle spacer envelope dimension measuring system and

The spring force measurement system includes a draw rod standard, an insertion tube and an extension tube, together with a cable received through the tubes connecting the standard and a load cell, in turn connected by the cable to a winch. The draw rod standard is located in the fuel bundle below the spacer having a spring whose spring force is to be measured. By drawing the standard through the spacer cell, the spring force is computed using the measured tension in the connecting cable as the standard is withdrawn and the known values of the coefficient of friction between the spacer spring projection and the draw rod standard and the combined weight of the cable and draw rod standard. The measuring process is repeated for next higher spacers.

Nuclear fuel bundle spacer spring force measurement system

The length gauge includes an elongated standards rod, an indicator location block carrying a gauge and an indicator set block. The set block is applied to the location block and the gauge is zeroed out at a known distance between the movable element on the gauge and a reference surface. Water rods are assembled to a tie plate and the gauge is used to measure the length of the adjustable length water rods. The location block receives in a recess a portion of the tie bar of the water rod. The standards rod engages the tie plate and the gauge pin engages the opposite end of the standards rod. Any deviation in the length of the water rod from a designed length is indicated on the gauge.

Length gauge for in situ measurement of water rod lengths in nuclear

An extraction tool for removing a partial length fuel rod from a fuel bundle assembly, wherein the partial length fuel rod has an upper end plug, the tool comprising an extension rod having a pair of gripper jaws mounted at one end thereof, the gripper jaws shaped and sized to engage the upper end plug; and a locking tube slidably received over the extension rod and engageable with the gripper jaws to lock the gripper jaws to the upper end plug.

Extraction tool for partial length fuel rods in nuclear fuel assemblies

End plugs for nuclear fuel rods are provided with a spot weld along the interior end face of the end plugs to seal any streamer openings or passages along the axis of the end plugs, thereby maintaining the fuel rods sealed at its opposite ends. The spot welds are applied by an automated laser welding system in which pallets of end plugs are supported on X-Y positioning tables below a laser movable in a vertical direction. By successively locating the end plugs in the pallet below the laser, the spot welds are formed along the axis of the end plugs and along the interior faces thereof sealing the end plugs.

Apparatus and methods for sealing end plugs for nuclear fuel rods

To measure fuel rod-centering forces exerted by double-acting springs assembled with different pairs of ferrules in a nuclear fuel bundle spacer, a gauge is provided to include an alignment rod and a probe carried by a handle for insertions into the ferrules of a ferrule pair. The alignment rod loads the side of the spring acting in its ferrule, while the other spring side exerts its fuel rod-centering force on a plunger mounted in the probe. The plunger is mechanically linked to a load cell which provides an electrical readout of the spring force.

Growing community of inventors

Wilmington, NC, United States of America

William C Peters