CA2766575C - Pallet for nuclear reactor retube - Google Patents

Abstract

A pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end-face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other. The pallet includes an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies. The pallet also includes an electrical cable connectable to the tool and a hydraulic hose for providing a pressurized fluid to the tool. The pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame, electrical cable and hydraulic hose.

Description

Attorney Docket No. 027813-9035-CA00 PALLET FOR NUCLEAR REACTOR RETUBE
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to U.S. Provisional Patent Application No.
61/432,981, filed January 14,2011.
BACKGROUND

[0002] The present invention relates to nuclear reactors. More particularly, the invention relates to equipment used in maintenance of nuclear reactors, such as for retubing a nuclear reactor. Typically, equipment for retubing operations is heavy and bulky. One piece of equipment includes a tool for performing one of the many functions performed during the retubing operation, as well as all of the electrical and hydraulic equipment associated with that tool. Each time a new function is performed, requiring a new tool, all of the equipment for the old tool must be uninstalled, and all of the equipment for the new tool must be installed in its place. This is time consuming and inefficient.
SUMMARY

[0003] In one embodiment, the invention provides a pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end-face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other. The pallet includes an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies. The pallet also includes at least one of an electrical cable connectable to the tool and a hydraulic hose for providing a pressurized fluid to the tool. The pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame, sensor cable and hydraulic hose.

[0004] In another embodiment, the invention provides a pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an Attorney Docket No. 027813-9035-CA00 end face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other. The pallet includes an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies. The pallet also includes a ram drive for pushing and pulling the tool towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes. The ram drive includes a ram drive connector for coupling to the tool. The pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame and ram drive connector.

[0005] In another embodiment, the invention provides a pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other. The pallet includes an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies. The pallet also includes a Z-axis drive for moving the elongated frame towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes.
The pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame.

[0006] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1 is a perspective view of a reactor core.

[0008] FIG. 2 is a perspective view of a fuel channel assembly.

Attorney Docket No. 027813-9035-CA00

[0009] FIG. 3 is a perspective view illustrating a pallet and a heavy worktable positioned on a retube platform for a nuclear reactor retubing operation.

[0010] FIG. 4 is an exploded perspective view of the pallet coupled to a top of the worktable.

[0011] FIG. 5 is an exploded perspective view of the pallet illustrated in FIG. 4.

[0012] FIG. 6 is a perspective view of a portion of the pallet illustrated in FIG. 4.

[0013] FIG. 7 is a perspective view of a Z-drive portion of the pallet illustrated in FIG. 5.

[0014] FIG. 8 is a perspective view of a ram drive portion of the pallet illustrated in FIG. 6.

[0015] FIG. 9 is a magnified view of a portion of the ram drive illustrated in FIG. 8

[0016] FIG. 10 is a magnified view of a tool coupled to the ram drive illustrated in FIG. 5.

[0017] FIG. 11 is a schematic illustration of a portion of the ram drive illustrated in FIG. 8.
DETAILED DESCRIPTION

[0018] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

[0019] FIG. 1 is a perspective of a reactor core of a CANDUTM-type reactor 6. The reactor core is typically contained within a vault that is sealed with an air lock for radiation control and shielding. A generally cylindrical vessel, known as a calandria 10, contains a heavy-water moderator. The calandria 10 has an annular shell 14 and a tube sheet 18 at a first end 22 and a second end 24. The tube sheets 18 include a plurality of bores that accept a fuel channel assembly 28. As shown in FIG. 1, a number of fuel channel assemblies 28 pass through the tube sheets 18 of calandria 10 from the first end 22 to the second end 24 along a corresponding axis A, which is shown in FIG. 2.

Attorney Docket No. 027813-9035-CA00

[0020] FIG. 2 is a cut-away view of the fuel channel assembly 28. As illustrated in FIG. 2, each fuel channel assembly 28 is surrounded by a calandria tube ("CT") 32. The CT 32 forms a first boundary between the heavy water moderator of the calandria 10 and the fuel bundles or assemblies 40. The CTs 32 are positioned in the bores on the tube sheet 18. A
CT rolled joint insert 34 within each bore is used to secure the CT 32 to the tube sheet 18.

[0021] A pressure tube ("PT") 36 forms an inner wall of the fuel channel assembly 28. The PT 36 provides a conduit for reactor coolant and the fuel bundles or assemblies 40. The PT 36, for example, generally holds two or more fuel assemblies 40 and acts as a conduit for reactor coolant that passes through each fuel assembly 40. An annulus space 44 is defined by a gap between the PT 36 and the CT 32. The annulus space 44 is normally filled with a circulating gas, such as dry carbon dioxide, helium, nitrogen, air, or mixtures thereof.
The annulus space 44 and gas are part of an annulus gas system. The annulus gas system has two primary functions.
First, a gas boundary between the CT 32 and PT 36 provides thermal insulation between hot reactor coolant and fuel within the PTs 36 and the relatively cool CTs 32.
Second, the annulus gas system provides an indication of a leaking CT 32 or PT 36 via the presence of moisture, deuterium, or both in the annulus gas.

[0022] An annulus spacer or garter spring 48 is disposed between the CT 32 and PT 36. The annulus spacer 48 maintains the gap between the PT 36 and the corresponding CT
32, while allowing the passage of the annulus gas through and around the annulus spacer 48. Maintaining the gap helps ensure safe and efficient long-term operation of the reactor 6.

[0023] As also shown in FIG. 2, an end fitting SO is attached around the fuel channel assembly 28 outside of the tube sheet 18 at each end 22, 24. At the front of each end fitting 50 is a closure plug 52. Each end fitting 50 also includes a feeder assembly 54. The feeder assemblies 54 feed reactor coolant into or remove reactor coolant from the PTs 36. In particular, for a single fuel channel assembly 28, the feeder assembly 54 on one end of the fuel channel assembly 28 acts as an inlet feeder, and the feeder assembly 54 on the opposite end of the fuel channel assembly 28 acts as an outlet feeder. As shown in FIG. 2, the feeder assemblies 54 can be attached to the end fitting 50 using a coupling assembly 56 including a number of screws, washers, seals, and/or other types of connectors.

=

Attorney Docket No. 027813-9035-CA00

[0024] Coolant from the inlet feeder assembly flows along a perimeter channel of the end fitting 50 until it reaches a shield plug 58. The shield plug 58 is contained inside the end fitting 50 and provides radiation shielding. The shield plug 58 also includes a number of openings that allow the coolant provided by the inlet feeder assembly to enter an end of a PT 36. A shield plug 58 located within the end fitting 50 at the other end of the fuel channel assembly 28 includes similar openings that allow coolant passing through the PT 36 to exit the PT
36 and flow to the outlet feeder assembly 54 through a perimeter channel of another end fitting 50 at the opposite face of the reactor 6. As shown in FIG. 1, feeder tubes 59 are connected to the feeder assemblies 54 that carry coolant to or away from the reactor 6.
100251 Returning to FIG. 2, a positioning hardware assembly 60 and bellows 62 are also coupled to each end fitting 50. The bellows 62 allows the fuel channel assemblies 28 to move axially. The positioning hardware assemblies 60 are used to set an end of a fuel channel assembly 28 in either a locked or unlocked position. In a locked position, the end of the fuel channel assembly 28 is held stationary. In an unlocked position, the end of the fuel channel assembly 28 is allowed to move. A tool can be used with the positioning hardware assemblies 60 to switch the position of a particular fuel channel assembly 28.
[0026] The positioning hardware assemblies 60 are also coupled to an end shield 64. The end shields 64 provide additional radiation shielding. Positioned between the tube sheet 18 and the end shield 64 is a lattice sleeve or tube 65. The lattice tube 65 encases the connection between the end fitting 50 and the PT 36 containing the fuel assemblies 40.
Shielding ball bearings 66 and cooling water surround the exterior the lattice tubes 65, which provides additional radiation shielding.
100271 It should be understood that although a CANDUTm-type reactor is illustrated in FIGS.
1 and 2, the methods and systems described below for retubing a reactor also applies to other types of reactors containing similar components as illustrated in FIGS. 1 and 2.
100281 During a retubing of the reactor core 6, many of the major components of the reactor core 6 are removed and replaced. Other components are inspected and/or repaired. For example, all of the fuel channel end fittings 50 are removed, all of the calandria tube inserts 34 are removed, the calandria tubes 32 are removed, the pressure tubes 36 are severed from the bellows =
Attorney Docket No. 027813-9035-CA00 62 and removed, and the associated annular spacers (e.g., garter springs) 48 are removed.
Various machine tools and material handling equipment must be provided adjacent end faces 68 of the reactor core 6. In order to accommodate tooling and materials used for at least these processes during a retube, a pallet 72 is provided adjacent each end of the reactor core 6. The pallet 72 is designed to serve as a modular base for mounting and supporting various tooling systems and can be controlled by one or more workstations.
100291 The pallet 72 may be supported on a retube platform ("RTP") 74 erected adjacent each end 68 of the reactor core 6. In some constructions, the pallet 72 may be mounted to a worktable 70 that is movable across the retube platform 74 (see FIGS. 3-4).
The pallet 72 includes a longitudinal axis B (FIG. 4) that is aligned substantially parallel to the axes A of the fuel channel assemblies 28. Once installed, the pallet 72 can remain on the RTP 74 or worktable 70 for the majority of the removal series.
100301 FIG. 5 illustrates an exploded view of the pallet 72. The pallet 72 includes an elongated frame including a base 76 and a carriage 77. The base 76 receives a Z-axis drive 84 and a ram drive 94. Electrical panels 79, or junction boxes, and a water-based hydraulic assembly 81 are coupled to the base 76. The pallet 72 may also include a lateral drive 85 for effectuating side-to-side movement, i.e., X-axis movement, of certain tools.
100311 The lateral drive 85 is used for material handling purposes.
When components, such as PTs 36 or CTs 32 are removed from the reactor core 6, they are placed into a long thin-walled tube located on the pallet 72, called a transfer can (not shown). The working position of a transfer can is in alignment with the ram drive 94. To facilitate efficient transfer can movement, a loading position is provided on the lateral drive 85 to allow an empty transfer can to be placed there at the same time the pallet 72 also supports a loaded a transfer can.
Once the loaded transfer can is removed from the pallet 72, the lateral drive 85 then moves the unloaded transfer can laterally to align it with the working axis of the pallet drives 84, 94.
The pallet tools are able to pass through the transfer can to reach into the reactor core 6. The purpose of the transfer cans is to provide some containment around the removed reactor component in order to limit contamination spread and to provide standardized features for handling and subsequent processing of the removed material.

Attorney Docket No. 027813-9035-CA00 100321 As shown in FIG. 6, the base 76, or elongated bed, is constructed from hollow beams 78. In other constructions, the base 76 may be constructed from other types of beams or other suitable structures, such as C-shaped beams, as illustrated in FIGS. 4-5. A
base 80 of the pallet 72 is provided with an interface 82 for coupling to the worktable 70 or RTP
74, as described above. For example, as shown in FIG. 6, the interface 82 may include brackets, or a key, configured to engage with keyways or mating slots on the worktable 70 or RTP
74. The pallet 72 is secured to the worktable 70 or RTP 74 using threaded fasteners. In other constructions, other suitable interfaces may be employed. Guide surfaces 126 incorporated with the base 76 and carriage 77 align the working axis of the end fitting flask 50, calandria tube insert flask 34, and calandria tube-pressure tube-garter spring 48 with the working axis of the pallet 72 and with the working axis of the tool thereon for easy installation.
100331 As illustrated in FIGS. 5 and 7, the Z-axis drive 84 is provided to advance and retract the pallet 72 relative to the worktable 70, or RTP 74, to which it is mounted (and relative to the reactor 6) in a Z-direction. More specifically, the Z-axis drive 84 advances and retracts the carriage 77 relative to the base 76. The Z-direction is defined parallel to the longitudinal axes of the fuel channel assemblies 28, i.e., towards and away from the end faces 68 of the reactor core 6. The Z-axis drive 84 includes a lead screw and guide system 86 coupled to the base 76, which is mounted on the top of the worktable 70 or RTP 74. The lead screw and guide system 86 includes a screw 88, such as an ACME screw, and a block and nut assembly 89.
The block and nut assembly 89 includes a traveling nut, such as a bronze ACME nut, mounted inside a block.
The block and nut assembly 89 travels axially along the screw 88, i.e., in the Z-axis direction, when the screw is rotated and is self locking to prevent the assembly 89 from being back driven.
The carriage 77 is coupled to the block and nut assembly 89, particularly to the block, for movement in the Z-axis direction relative to the base 76. The Z-axis drive 84 also includes a motor 92, such as a servomotor, coupled to the screw 88 for rotating the screw 88 to effect the linear motion of the pallet 72. In the illustrated construction, two motors 92 are employed, one at each axial end of the screw 88, for redundancy. Motor redundancy is particularly useful in a nuclear reactor environment in which motors are potentially exposed to radiation, which may cause motor failure. A control system, such as a remote control system 93 illustrated schematically in FIG. 4, controls the Z-axis drive 84.

Attorney Docket No. 027813-9035-CA00 [0034] Because the Z-axis drive 84 is located between the pallet 72 and the worktable 70 or RTP 74, the upper structure of the pallet 72 is strengthened to support heavy flasks, and space is made available in front of the pallet 72 for guide sleeves and shield tubes.
The pallet 72 may function as a base tool and accommodate different tools or accessories for calandria tube insert release, calandria tube insert removal, and the calandria tube-pressure tube-garter spring removal series.
[0035] The pallet 72 further includes the ram drive 94, which can advance and retract accessory heads coupled to the pallet 72 with respect to the pallet 72. The ram drive 94 may include a drive assembly 96 (FIG. 8), such as a chain drive assembly. In the illustrated construction, the ram drive 94 includes a chain 98, which is preferably a semi-rigid or "push pull" chain configured for push and pull operation. For example, the chain 98 is a push pull chain manufactured by Serapid, Inc. In some constructions, the chain 98 uses links that pivot freely one way, but lock in the opposite direction to form a rigid ram that can be pushed (see FIG. 11). The chain 98 forms a straight ram when the front end of the chain is guided straight inside a retrieval head 106 or other accessory tool. The ram drive 94 includes a motor 110 operably coupled to drive a chain drive shaft 112 (FIG. 11). In the illustrated construction (FIG.
8), the motor 110 includes two servomotors coupled to a 90 degree dual input gear box 114 for redundancy. Motor redundancy is particularly useful in a nuclear reactor environment in which motors are potentially exposed to radiation, which may cause motor failure.
The gear box 114 converts rotation of the motor 110 into rotation of the chain drive shaft 112, which is coupled to a sprocket 116 that engages the links of the chain 98 for driving the chain 98. A control system, such as remote control system 93 shown in FIG. 4, controls the drive assembly 96. In other constructions, other types of ram drives may be employed to push and pull the tool towards and away from the end face 68 of the nuclear reactor core 6.
[0036] The chain 98 may be stored or substantially enclosed within the bed or base 76 of the pallet 72. The chain 98 provides a long straight ram that includes a fold 100 at an intermediate point in the chain 98 coupled with a reaction plate roller 120. A first end of the chain 98 is fixed at an anchor 102, which is fixed with respect to the base 76 of the pallet 72.
As illustrated in FIG. 9, a second end of the chain 98 is coupled to a connector, such as a quick release pin 104 and bracket 105, for coupling to the retubing tool, such as the calandria tube retrieval head 106.

Attorney Docket No. 027813-9035-CA00 The retrieval head 106 (FIGS. 5 and 10), or other tool being employed, includes a connection plate 108 extending from the retrieval head 106 or other tool. The connection plate 108 couples to the quick release pin assembly 104 and has a substantially rectangular cuboid shape having an aperture therein. The rectangular cuboid shape of the connection plate 108 is received by the bracket 105 such that apertures in the connection plate 108 and bracket 105 align to receive the pin 104 therethrough, thereby coupling the connection plate 108 to the bracket 105. Thus, the retrieval head 106, or other tool being employed, is coupled to the ram drive 94 for linear motion towards and away from the nuclear reactor 6, i.e., in the Z-direction. The retrieval head 106 defines a longitudinal axis C that is aligned by the guide surfaces 126 to be substantially parallel to the axes A of the fuel channel assemblies 28, or in some cases, as necessary, substantially aligned with an axis A of a fuel channel assembly 28. As the first end of the chain 98 is fixed at the anchor 102 and the second end moves axially to drive the retrieval head 106, the fold 100 moves axially with the reaction plate roller 120 within the base 76 of the pallet 72. The reaction plate roller 120 acts as an idle gear for managing the different lengths of the chain 98, e.g., to prevent the chain 98 from folding over on itself in an uncontrolled manner or from bending too sharply beyond a minimum bend radius of an electrical cable 122 and hydraulic hoses 124, which will be described in greater detail below.
100371 As illustrated in FIG. 9, an electrical cable 122, or cables, and a hydraulic hose 124, or hoses, provide a conduit for electrical cables and hydraulic fluid, respectively, to the tool or accessory coupled to the ram drive 94, as needed. For example, the electrical cables may include sensor cables for sensors associated with the tool and power cables for powering the tool, e.g., for powering an electric motor of the tool, as well as other electrical cables. In some constructions, a wireless system may communicate data from the sensors. The hydraulic hose 124 may include two hydraulic hoses. The electrical cables 122 and hydraulic hoses 124 thread along the chain 98 to the quick release pin assembly 104 at the front end of the chain 98. The cables 122 and hoses 124 move with the chain 98 alongside the chain 98, i.e., are fixed with respect to the chain 98. The accessory heads, such as the retrieval head 106 shown in FIG. 10, mount to the quick release pin assembly 104 and, if necessary, connect to an end of the electrical cables 122 and hydraulic hoses 124. Another end of the electrical cables 122 may connect to the electrical panels 79, and another end of the hydraulic hoses 124 may connect to the hydraulic Attorney Docket No. 027813-9035-CA00 assembly 81, which provides a pressurized fluid to the hydraulic hoses 124 and ultimately to the retrieval head 106 or other tool. In some constructions, the hydraulic assembly 81 is a water hydraulic assembly, as opposed to oil, to assure no oil is leaked into the reactor 6 when the accessory heads enter the reactor 6. In other constructions, the hydraulic assembly 81 may be an oil hydraulic assembly.
100381 The chain 98 can clear permanent vault structures while producing a straight ram that points towards the reactor 6. The pallet 72, including the ram drive 94 may be operated by the remote control system 93 shown in FIG. 4. The electrical panels 79, which are coupled to the pallet 72, interface with the ram drive 94, the Z-axis drive 84, the electrical cables 122, the lateral drive 85 and the remote control system 93. In some constructions, the wireless system may communicate the control signals to the pallet 72.
[0039] The pallet 72 is configured to operate within the confined space defined by any permanent vault structures in front of the end faces 68 of the reactor core 6.
The pallet 72 is transported into the vault using a vault trolley system, reactor area cranes, and floor dollies for installation on the worktable 70 or RTP 74. Once the pallet 72 has been installed and commissioned on the worktable 70, for example, for pressure tube removal, it remains on the worktable 70 so that it can be used for calandria tube insert release, calandria tube insert removal, and calandria tube removal.
[0040] In operation, an operator installs a first of the retubing tools on the pallet 72 by connecting the tool to the pin 104 and bracket 105. Thus, the first of the retubing tools is configured for movement towards and away from the end face 68 of the reactor core 6, as described above, by way of the ram drive 94 and also by way of the Z-axis drive 84. If necessary, the operator also connects the sensor cable 122 to the first of the retubing tools and, if necessary, the operator also connects the hydraulic hose 124 to the first of the retubing tools.
When another of the retubing tools is required for performing another portion of the retubing operation, the operator disconnects the first of the retubing tools and installs a second of the retubing tools on the pallet 72 in the same manner as described above for the first of the retubing tools. Thus, a first fuel channel assembly 28 component can be inserted or removed, i.e., a first retubing operation can be performed, using a first of the tools, and a second retubing operation Attorney Docket No. 027813-9035-CA00 can be performed using a second of the tools (etc.) without having to move the drive components (e.g., the ram drive 94 and the Z-axis drive 84) for the tool, the electrical components for the tool (e.g., the electrical cables 122 and the electrical panels 79 for the tool), and the hydraulic components for the tool (e.g., the hydraulic hoses 124 and the hydraulic assembly 81). In other words, the pallet 72 eliminates the need for each tool to have its own drive components, electrical components and hydraulic components, which are heavy, laborious and time consuming to move each time a new tool must be employed in the retubing operation.
[0041]
Thus, the invention provides, among other things, a single pallet operable to provide drive components, electrical components and hydraulic components for various insert and removal tools and accessories. Various features and advantages of the invention are set forth in the following claims.

Claims (24)

What is claimed is:

1. A pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end-face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other, the pallet comprising:
an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies; and at least one of an electrical cable connectable to the tool and a hydraulic hose for providing a pressurized fluid to the tool;
wherein the pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame and the same electrical cable and/or hydraulic hose.

2. The pallet of claim 1, further comprising a hydraulic assembly coupled to the elongated frame for supplying the pressurized fluid to the hydraulic hose.

3. The pallet of claim 2, further comprising an electrical panel coupled to the elongated frame for receiving the electrical cable.

4. The pallet of claim 1, further comprising a ram drive for pushing and pulling the tool towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes, the ram drive including a ram drive connector for coupling to the tool.

5. The pallet of claim 4, wherein the ram drive connector includes a quick release pin and bracket for coupling to the tool.

6. The pallet of claim 5, wherein the ram drive further comprises:

a push pull chain, the ram drive connector being coupled to a free end of the push pull chain; and a drive assembly including a motor for driving the push pull chain towards and away from the end face of the nuclear reactor core.

7. The pallet of claim 4, wherein the ram drive further comprises:
a push pull chain; and a drive assembly including a motor for driving the push pull chain towards and away from the end face of the nuclear reactor core;
wherein the electrical cable and the hydraulic hose are threaded alongside the push pull chain for movement with the push pull chain.

8. The pallet of claim 4, further comprising a control system for controlling the ram drive to move the tool towards and away from the end face of the nuclear reactor core.

9. The pallet of claim 1, further comprising a Z-axis drive for moving the elongated frame towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes.

10. The pallet of claim 1, wherein the electrical cable includes a sensor cable.

11. The pallet of claim 1, wherein the pallet includes the electrical cable and the hydraulic hose.

12. The pallet of claim 1, further comprising a wireless system configured to wirelessly communicate at least one of a control signal and sensor data.

13. A pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other, the pallet comprising:
an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies; and a ram drive for pushing and pulling the tool towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes, the ram drive including a ram drive connector for coupling to the tool;
wherein the pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame and ram drive connector.

14. The pallet of claim 13, wherein the ram drive connector includes a quick release pin and bracket for coupling to the tool.

15. The pallet of claim 14, wherein the ram drive further comprises:
a push pull chain, the connector coupled to a free end of the push pull chain;
and a drive assembly including a motor for driving the push pull chain towards and away from the end face of the nuclear reactor core.

16. The pallet of claim 15, wherein the motor includes first and second motors for redundancy and wherein the drive assembly further comprises a 90 degree dual input gear box for converting rotational motion of a motor drive shaft into rotational motion of a perpendicularly aligned shaft for driving the push pull chain.

17. The pallet of claim 13, further comprising a control system for controlling the ram drive to move the tool towards and away from the end face of the nuclear reactor core.

18. The pallet of claim 13, further comprising a Z-axis drive for moving the elongated frame towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes.

19. The pallet of claim 13, further comprising a wireless system configured to wirelessly communicate at least one of a control signal and sensor data.

20. A pallet for supporting one of a plurality of tools for a nuclear reactor retubing operation, the pallet positionable adjacent to an end face of a nuclear reactor core having a plurality of fuel channel assemblies having longitudinal axes aligned substantially parallel to each other, the pallet comprising:
an elongated frame extending generally parallel to the longitudinal axes of the fuel channel assemblies for supporting one of the tools for the nuclear reactor retubing operation, the frame having guide surfaces for aligning the tool parallel to the longitudinal axes of the fuel channel assemblies; and a Z-axis drive for moving the elongated frame towards and away from the end face of the nuclear reactor core in a direction substantially parallel to the longitudinal axes;
wherein the pallet is configured to interchangeably accommodate another of the plurality of tools using the same elongated frame.

21. The pallet of claim 20, wherein the Z-axis drive includes a lead screw and guide system.

22. The pallet of claim 21, wherein the Z-axis drive further comprises a first motor coupled to a first end of the screw and a second motor coupled to a second end of the screw, the first and second motors providing redundancy for driving the lead screw and guide system.

23. The pallet of claim 20, further comprising a local electrical panel for interfacing to the Z-axis drive.

24. The pallet of claim 20, further comprising a wireless system configured to wirelessly communicate at least one of a control signal and sensor data.