Cutting device

Abstract

To provide a device capable of removing safely, an obstacle when taking out, fuel which has been used, from a fuel storage rack.SOLUTION: There is provided a cutting device X for removing an object which is an obstacle when taking out, fuel which has been used, from a fuel storage rack which is formed of a plurality of rack cells, the device comprises: a device main body 1; a fixing mechanism 2; and a control part 3. The device main body 1 comprises: a movement mechanism 11; and a cutting mechanism 12. The movement mechanism 11 can move the cutting mechanism 12 in a three-dimensional manner, and the cutting mechanism 12 includes a substantially rod-shaped cutting tool main body 12a, the cutting tool main body 12a can cut a direction which is substantially orthogonal to a longitudinal direction of the cutting tool main body. The fixing mechanism 2 can fix the device main body 1 to the fuel storage rack. The control part 3 remotely operates the fixing mechanism 2, the movement mechanism 11, and the cutting mechanism 12.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus for removing obstacles during spent fuel removal operations. [Background technology]

[0002] As a result of the Great East Japan Earthquake that occurred in March 2011, a hydrogen explosion occurred at Unit 3 of the Fukushima Daiichi Nuclear Power Plant, and debris from the reactor building damaged by the explosion was scattered as rubble on the fuel storage racks in the spent fuel pool.

[0003] The rubble had gotten into the gaps between the channel box covering the fuel assemblies and the channel fasteners fastening the channel box to the fuel assemblies, as well as the gaps between the channel box and the rack cell, hindering the work of removing the spent fuel.

[0004] However, there has never been a suitable device to safely remove the rubble that has gotten into the gaps between the channel box and the channel fastener, and between the channel box and the rack cell on the fuel storage rack, which is located in a special location at a depth of approximately 7 meters in the spent fuel pool. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] none Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and an object to be achieved is to provide an apparatus that can safely remove obstacles when removing spent fuel from a fuel storage rack. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a cutting device for removing an object that obstructs the removal of spent fuel from a fuel storage rack that is composed of a plurality of rack cells, the cutting device comprising: The apparatus includes a device body, a fixing mechanism, and a control unit, and the device body has a moving mechanism and a cutting mechanism; the moving mechanism is configured to be able to move the cutting mechanism three-dimensionally, and the cutting mechanism includes a substantially rod-shaped cutting tool main body; the cutting tool body is configured to be capable of cutting in a direction substantially perpendicular to a longitudinal direction thereof, and the fixing mechanism is configured to be capable of fixing the device body to the fuel storage rack, The control unit is configured to be able to remotely control the fixing mechanism, the moving mechanism, and the cutting mechanism.

[0008] According to the present invention, a roughly rod-shaped cutting tool can be remotely controlled from a control unit to enter narrow spaces and perform cutting, making it possible to safely cut and remove obstacles without damaging the channel box contained in the fuel storage rack.

[0009] In a preferred embodiment of the present invention, the movement mechanism includes an X-axis movement device, a Y-axis movement device, and a Z-axis movement device for linearly moving the cutting mechanism on each axis.

[0010] With this configuration, obstacle removal work can be carried out efficiently on a fuel storage rack made up of a plurality of rack cells arranged in a grid pattern.

[0011] In a preferred embodiment of the present invention, the X-axis movement device, the Y-axis movement device, and the Z-axis movement device each include an instrumentation unit capable of measuring the amount of movement on each axis of the cutting mechanism.

[0012] With this configuration, the spatial position of the cutting mechanism can be expressed in spatial coordinates and grasped numerically, thereby improving the accuracy and efficiency of work.

[0013] In a preferred embodiment of the present invention, the instrumentation section is configured so that compressed gas can be injected thereinto.

[0014] By using this configuration, the internal pressure of the instrumentation unit can be kept higher than the external water pressure by injecting compressed gas, making it possible to prevent water from entering the instrumentation unit and ultimately preventing submersion and failure of instrumentation equipment.

[0015] In a preferred embodiment of the present invention, the cutting mechanism includes a camera unit capable of photographing the area of ​​the cutting tool body to be cut.

[0016] With this configuration, the user can safely remove the obstacle while visually checking the condition of the obstacle and the channel box.

[0017] In a preferred embodiment of the present invention, the camera unit includes a plurality of camera bodies and a camera fixing unit, and the camera fixing unit is configured to be able to change the arrangement of the plurality of camera bodies.

[0018] With this configuration, even if the installation orientation of the device is changed, the camera can be positioned to suit each orientation.

[0019] In a preferred embodiment of the present invention, the control unit is configured to be able to automatically control the movement mechanism and the cutting mechanism based on input cutting parameters.

[0020] With this configuration, the obstacle cutting work is performed automatically based on the cutting parameters input in advance, allowing for fine cutting that would be difficult to perform manually. This makes it possible to prevent vibration of the cutting tool body and entanglement of the channel box.

[0021] In a preferred embodiment of the present invention, the control unit is configured to be able to perform an increment operation on the movement mechanism.

[0022] This configuration allows for easy fine adjustment of the cutting start position, improving the accuracy and safety of the work.

[0023] In a preferred embodiment of the present invention, the control unit is configured to be able to automatically control the movement mechanism so that the cutting mechanism is located at the center of gravity of the device body.

[0024] With this configuration, the center of gravity can be easily adjusted when installing the device on a crane, improving the safety and efficiency of crane operations.

[0025] In a preferred embodiment of the present invention, the fixing mechanism includes a plurality of main fixing devices, each of which is a substantially columnar body that can be inserted into the rack cell.

[0026] With this configuration, the device according to the present invention can be easily installed on a fuel storage rack by inserting the main fixing device into the rack cell.

[0027] In a preferred embodiment of the present invention, each of the plurality of primary fixing devices includes an auxiliary fixing device for fixing the primary fixing device within the rack cell.

[0028] With this configuration, the main fixing device inserted into the rack cell is fixed more firmly, so that the device according to the present invention can sufficiently withstand the reaction force during cutting. [Effects of the Invention]

[0029] According to the present invention, it is possible to provide an apparatus that can safely remove obstacles when removing spent fuel from a fuel storage rack. [Brief explanation of the drawings]

[0030] [Figure 1] 1A and 1B are a schematic perspective view and a side view of a cutting device according to an embodiment of the present invention. [Figure 2] 1A and 1B are a perspective view, a plan view, and an example of camera arrangement of a cutting mechanism according to an embodiment of the present invention; [Figure 3] 1 is an example of a cutting operation according to an embodiment of the present invention. [Figure 4] 1 is a schematic diagram of a fixing mechanism according to an embodiment of the present invention. [Figure 5] 10 is an example of an operation screen displayed on a control unit according to an embodiment of the present invention. [Figure 6] 10 is an example of an operation screen displayed on a control unit according to an embodiment of the present invention. [Figure 7] 10 is an example of an operation screen displayed on a control unit according to an embodiment of the present invention. [Figure 8] 10 is an example of an operation screen displayed on a control unit according to an embodiment of the present invention. [Figure 9] 1 is a schematic perspective view of a cutting device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] Hereinafter, a cutting device according to an embodiment of the present invention will be described with reference to Figures 1 to 9. Note that the embodiment described below is an example of the present invention, and the present invention is not limited to the following embodiment. Also, the symbol X indicates a cutting device according to an embodiment of the present invention.

[0032] In addition, in Figures 1 to 9, pipes for supplying compressed gas, hydraulic oil, etc. to each part, and wiring for transmitting video and other signals, power supply, etc. are not shown, but the appropriate connection relationship of these pipes and wiring will be easily understood by those skilled in the art.

[0033] As shown in FIG. 1(A), the cutting device X includes a device body 1, a fixing mechanism 2, and a control unit 3.

[0034] The device body 1 has a moving mechanism 11 and a cutting mechanism 12. The moving mechanism 11 includes an X-axis moving device 11a, a Y-axis moving device 11b, and a Z-axis moving device 11c. The cutting mechanism 12 will be described in detail later.

[0035] The X-axis moving device 11a includes a hydraulic motor om, an instrumentation unit is, a ball screw bs, and a slide rail sr.

[0036] That is, the X-axis moving device 11a converts the rotational motion of the hydraulic motor om into linear motion using the ball screw bs, thereby linearly moving the Y-axis moving device 11b, the Z-axis moving device 11c, and the cutting mechanism 12 in the X-axis direction. The slide rail sr also assists this linear movement.

[0037] Furthermore, the instrumentation unit is can measure the amount of movement in the X axis from the amount of rotation of the hydraulic motor om, etc., and can therefore measure the X coordinate of the cutting mechanism 12 based on this.

[0038] The instrumentation unit is also provided with a connection port cn through which compressed gas can be injected into the instrumentation unit is. This allows the internal pressure of the instrumentation unit is to be maintained higher than the external pressure, and prevents water from entering the instrumentation unit is, especially when it is underwater.

[0039] The Y-axis moving device 11b and the Z-axis moving device 11c are also realized by the same configuration as the X-axis moving device 11a.

[0040] The Y-axis moving device 11b can linearly move the Z-axis moving device 11c and the cutting mechanism 12 in the Y-axis direction, and the Y coordinate of the cutting mechanism 12 can be measured by the instrumentation unit is.

[0041] The Z-axis moving device 11c can move the cutting mechanism 12 linearly in the Z-axis direction, and the Z coordinate of the cutting mechanism 12 can be measured by the instrumentation unit is.

[0042] Therefore, by the cooperation of the X-axis moving device 11a, the Y-axis moving device 11b, and the Z-axis moving device 11c, the cutting mechanism 12 can be moved three-dimensionally, and the spatial coordinates of the cutting mechanism 12 can be measured from the amount of movement on each axis measured by the instrumentation unit is of each device.

[0043] The fixing mechanism 2 has a first main fixing device 21 and a second main fixing device 22, which are substantially columnar bodies, and these are attached to the device body 1 via a base ba.

[0044] The control unit 3 has a main breaker for controlling the power supply to the device main body 1 and the fixing mechanism 2, and a touch panel (not shown) for controlling other operations, and is installed in a location separate from the device main body 1 and the fixing mechanism 2.

[0045] 1(B) is a side view (partially omitted) of device X, seen from the AA′ direction. First main fixing device 21 includes a plurality of pillars 21 a and auxiliary fixing device 21 b, and second main fixing device 22 similarly includes a plurality of pillars 22 a and auxiliary fixing device 22 b.

[0046] 2(A) and 2(B), the cutting mechanism 12 includes a cutting tool body 12a and a camera unit 12b, as well as a hydraulic motor om for rotationally driving the cutting tool body 12a.

[0047] The cutting tool body 12a may be a grinder-shaped one that can rotate horizontally and vertically, but an end mill that can easily get into narrow spaces and perform delicate processing is preferably used.

[0048] Camera unit 12b includes a plurality of camera bodies 12b11, 12b12, and 12b13, and a plurality of camera fixing units 12b21, 12b22, 12b23, 12b24, and 12b25, respectively. In addition, a general underwater camera and its accessories can be suitably used for each camera body and the transmission line for the video signal.

[0049] Furthermore, as shown in Figure 2(C), the positions of the camera bodies 12b11, 12b12, and 12b13 can be selected from multiple camera fixing parts 12b21, 12b22, 12b23, 12b24, and 12b25, making it possible to optimally position them according to the orientation of the cutting mechanism 12.

[0050] Figure 3(A) is a top view of the obstacle removal work, and the channel box fb covering the spent fuel is fastened to the fuel assembly by a channel fastener cf located at one corner of its upper end. The channel fastener cf is a device that not only connects the channel box fb and the fuel assembly with its screw threads, but also has a pair of two-sided leaf springs whose purpose is to maintain the spacing between the fuel assemblies inside the reactor.

[0051] FIG. 3(B) is a side view of the work. The rack guide portion Lg at the top of the fuel rack is narrower than the inner diameter of the rack cell, and during normal fuel removal, the leaf spring of the channel fastener cf comes into contact with and is pushed against the rack guide portion Lg, bending it inward as the fuel is removed. However, as shown in Figure 3(B), if an obstacle ob gets inside the leaf spring of the channel fastener cf, even if the rack guide portion Lg comes into contact with the leaf spring of the fastener when the fuel is pulled up, the leaf spring cannot be pushed down due to the obstacle ob, and the leaf spring cannot pass through the rack guide portion Lg.

[0052] That is, if an obstacle ob gets into the gap between the channel fastener cf and the channel box fb, it will interfere with the rack guide portion Lg, making it impossible to remove the channel box fb (spent fuel).

[0053] That is, the device X cuts the diagonally shaded portion of the rack guide portion Lg to release the interference between the channel fastener cf and the rack guide portion Lg, thereby enabling the channel box fb (spent fuel) to be removed.

[0054] Furthermore, the cutting tool body 12a can cut the east face of the rack guide portion Lg at position p1 and the north face of the rack guide portion Lg at position p2, so it can handle any situation where an obstacle ob gets into either face of the channel fastener cf.

[0055] As shown in Figures 4 and 1(A), the first main fixing device 21 is configured so that multiple pillar-shaped bodies 21a surround the auxiliary fixing device 21b, so that the entire device is approximately pillar-shaped and its outer dimensions are slightly smaller than the inner diameter of the rack cell. Therefore, as shown in FIG. 4, simply by inserting the first main fixing device 21 into the rack cell fc, the base ba and therefore the device main body 1 (not shown) can be roughly fixed onto the fuel storage rack fL.

[0056] The auxiliary fixing device 21b includes a hydraulic cylinder os, a conversion mechanism co, and a tension member tm.

[0057] Since the direction of the force is converted by the conversion mechanism co, when the hydraulic cylinder os is lowered, as shown in FIG. 4(A), a force acts to retract the tensioning portion tm. Also, as shown in Figure 4(B), when the hydraulic cylinder os rises, a force acts on the tension portion tm so that it protrudes, and the tension portion tm comes into contact with the rack guide portion Lg, thereby obtaining a fixing force. The user can control the up and down movement of the hydraulic cylinder os from the control unit 3 and switch the auxiliary fixing device 21b between the fixed state and the non-fixed state from the control unit 3.

[0058] The second main fixing device 22 is configured in the same manner as the first main fixing device 21, and the fixing mechanism 2 has a plurality of main fixing devices 21, 22, so that the device X can be fixed more firmly.

[0059] 5 to 8 are examples of operation screens displayed on the touch panel of the control unit 3. FIG.

[0060] FIG. 5(A) shows the main screen w1 used when operating the device X, and allows control of each operation in the cutting work.

[0061] In this embodiment, by pressing any one of the buttons i11 to i15, it is possible to control the start, continuation, pause, restart, and end of the cutting operation of the device X based on the settings displayed on the screen.

[0062] Moreover, by pressing the button i16, the cutting mechanism 12 of the device X can be moved to the origin position on the spatial coordinate system.

[0063] Moreover, by pressing the button i17, the cutting operation of the device X can be forcibly terminated.

[0064] Furthermore, by pressing the button i18, a page switching tab (not shown) is displayed, from which it is possible to move to other pages such as various setting screens.

[0065] FIG. 5(B) is a setting screen w2, which allows the user to select the operation type and rack type for cutting work.

[0066] In this embodiment, the type of operation can be selected from cutting operation in the XY directions, cutting operation in the Z direction, and movement of the center of gravity position by pressing buttons i21 to i23.

[0067] In addition, the rack type can be selected as either a 20-body rack or a 30-body rack by pressing buttons i24 and i25.

[0068] Finally, the setting change is confirmed by pressing button i26.

[0069] FIG. 6(A) is a setting screen w3, which allows the user to select the device direction and cutting surface for cutting work.

[0070] In this embodiment, the installation direction of the device can be selected from 0°, 90°, 180°, and 270° by pressing buttons i31 to i34. In this embodiment, the position where the hydraulic motor om of the Y-axis moving device 11b faces north as shown in Figure 3(A) is defined as 0°, and the installation direction of the device is defined as 90°, 180°, and 270° counterclockwise from there.

[0071] In addition, either the north or east face can be selected as the cutting face by pressing buttons i35 and i36.

[0072] Finally, press button i37 to confirm the setting changes.

[0073] FIG. 6(B) is a setting screen w4, which allows the cutting start position and cutting stop position in the cutting work to be set based on spatial coordinates.

[0074] In this embodiment, numerical input is accepted by pressing each numerical value in the start position coordinate display section i41, and the spatial coordinates of the start position are set based on the input value. The numeric values ​​may be input using a numeric keypad on a touch panel or physical buttons, but any method that allows appropriate numeric value input may be used.

[0075] The spatial coordinates can also be set in the stop position coordinate display section i42 by the same operation, and finally, the start position and stop position are confirmed by pressing the button i43.

[0076] FIG. 7(A) is an inching operation screen w5 for the cutting mechanism 12, and as shown here, the control unit 3 can inching the cutting mechanism 12 at high or low speed while checking the current coordinates of the cutting mechanism 12.

[0077] Therefore, the user can select any axis and speed, and while pressing either "forward" or "reverse," can operate the moving mechanism 11 in an incrementing motion so that the cutting mechanism 12 moves slightly on the selected axis, making it easy to determine the appropriate cutting start position coordinates.

[0078] FIG. 7(B) is a setting screen w6, which allows the user to select a machining mode for cutting work.

[0079] In this embodiment, any of the processing modes, manual, automatic one-step, automatic one-cycle, and fully automatic, can be selected by pressing buttons i61 to i64, and can be confirmed by pressing button i65.

[0080] In the "fully automatic" mode, cutting is performed based on the cutting parameters set on the parameter setting screen w7, which will be described later.

[0081] In this embodiment, one cycle consists of three steps: infeed, cutting, and return. That is, in the "automatic one-cycle" mode, the fully automatic cutting operation is performed and stopped for each cycle. In the "automatic one-step" mode, the fully automatic cutting operation is performed and stopped for each step.

[0082] In addition, in the "Automatic One Cycle" and "Automatic One Step" modes, when the cutting operation stops after each cycle or step, you can choose to continue or end the cutting operation by pressing either button i12 or i15 on screen w1.

[0083] This allows the user to proceed with the cutting process while checking the status for each cycle or step, thereby improving the safety and accuracy of the work.

[0084] FIG. 8(A) is a parameter setting screen w7, which allows the user to set cutting parameters for cutting work.

[0085] The cutting depth setting unit i71 accepts numerical input and allows the user to set the cutting depth and return distance of the cutting tool body 12a. This enables cutting with very shallow cutting depths and return distances that would be difficult to achieve manually, and reduces chatter vibrations during cutting.

[0086] Furthermore, the cycle number setting section i72 can accept numerical input and set the number of cycles for the fully automatic cutting operation.

[0087] Furthermore, the workpiece thickness setting section i73 accepts numerical input and allows the thickness of the object to be cut, that is, the workpiece, to be set. Furthermore, if the product of the difference between the cutting depth and return depth set up to this point and the number of cycles exceeds the thickness of the workpiece, a warning message (not shown) will be displayed, thereby preventing dangerous cutting operations from being performed.

[0088] As shown in FIG. 8(B), the control unit 3 is configured to be able to automatically control the moving mechanism 11 so that the cutting mechanism 12 is located at the center of gravity of the device body 1 based on preset center of gravity coordinates.

[0089] Therefore, the user can simply press "Start Movement" to move the cutting mechanism 12 to the center of gravity of the device main body 1, thereby improving safety and work efficiency when lifting the device with a crane.

[0090] 9, the device X is installed on a fuel storage rack fL by lifting with a crane. Therefore, the device X further includes a substantially box-shaped frame fr, which has a lifting hook sh and a hook receiving base hr. This makes it easier to perform slinging work when lifting with a crane, improving work efficiency.

[0091] According to this embodiment, the approximately rod-shaped cutting tool body 12a can be remotely controlled from the control unit 3 to enter narrow spaces and perform cutting, making it possible to safely cut and remove obstacles without damaging the channel box fb (spent fuel) stored in the fuel storage rack fL.

[0092] Furthermore, since the moving mechanism 11 includes an X-axis moving device 11a, a Y-axis moving device 11b, and a Z-axis moving device 11c, the cutting mechanism 12 can be moved linearly on the fuel storage rack fL, which is composed of multiple rack cells arranged in a grid pattern, allowing for efficient obstacle removal work.

[0093] Furthermore, since the X-axis moving device 11a, the Y-axis moving device 11b, and the Z-axis moving device 11c each include an instrumentation unit is that can measure the amount of movement on each axis of the cutting mechanism 12, the spatial position of the cutting mechanism 12 can be grasped numerically, improving the accuracy and efficiency of the work.

[0094] Furthermore, since the instrumentation unit is configured so that compressed gas can be injected into it, the internal pressure of the instrumentation unit is can be kept higher than the external water pressure by injecting compressed gas, thereby making it possible to prevent water from entering the instrumentation unit is and ultimately preventing instrumentation equipment from being submerged and causing malfunction.

[0095] Furthermore, since the cutting mechanism 12 includes a camera unit 12b capable of photographing the area to be cut by the cutting tool body 12a, the user can safely remove obstacles while visually checking the cutting status.

[0096] Furthermore, the camera unit 12b includes a plurality of camera bodies 12b11, 12b12, 12b13 and camera fixing parts 12b21, 12b22, 12b23, 12b24, 12b25, and is configured so that the position of each camera body can be changed. Therefore, even if the installation orientation of the device is changed, it is possible to position each camera according to each orientation.

[0097] Furthermore, the control unit 3 is configured to automatically control the moving mechanism 11 and cutting mechanism 12 based on the input cutting parameters, allowing for fine cutting that would be difficult to perform manually. This makes it possible to prevent vibration of the cutting tool body and entanglement of the channel box.

[0098] Furthermore, since the control unit 3 is configured to be able to perform increment operation of the moving mechanism 11, fine adjustment of the cutting start position can be easily performed, thereby improving the accuracy and safety of the work.

[0099] Furthermore, the control unit 3 is configured to automatically control the moving mechanism 11 so that the cutting mechanism 12 is located at the center of gravity of the device body 1, which makes it easy to adjust the center of gravity when installing the device X by crane, thereby improving the safety and efficiency of crane operations.

[0100] Furthermore, the fixing mechanism 2 has a plurality of main fixing devices 21 and 22, which are roughly cylindrical bodies that can be inserted into the rack cell, so that the main fixing devices 21 and 22 can be inserted into the rack cell and the device X can be easily installed on the fuel storage rack fL.

[0101] Furthermore, since the multiple main fixing devices 21 and 22 each include an auxiliary fixing device 21b and 22b for fixing the main fixing devices 21 and 22 within the rack cell, the device X is firmly fixed and can sufficiently withstand the reaction force during cutting.

[0102] It should be noted that the configurations and functions shown in the above-described embodiments are merely examples and can be modified in various ways based on design requirements and the like. [Explanation of symbols]

[0103] X cutting equipment 1. Device body 11 Moving mechanism 11a X-axis moving device 11b Y-axis moving device 11c Z-axis moving device 12 Cutting mechanism 12a Cutting tool body 12b Camera section 2 Fixing mechanism 21 First main fixing device 21a Column 21b Auxiliary fixation device 22 Second main fixing device 22a Column 22b Auxiliary fixation device 3. Control Unit is Instrumentation Department fb channel box (spent fuel) cf channel fastener Obstacles

Claims

1. A cutting device for removing an object that obstructs the removal of spent fuel from a fuel storage rack that is composed of a plurality of rack cells, The device comprises a device body, a fixing mechanism, and a control unit, the device body has a moving mechanism and a cutting mechanism, the movement mechanism includes an X-axis movement device, a Y-axis movement device, and a Z-axis movement device for linearly moving the cutting mechanism on each axis, and the cutting mechanism includes a cutting tool body; the fixing mechanism is configured to be able to fix the device main body to the fuel storage rack, the control unit is configured to be able to remotely control the fixing mechanism, the moving mechanism, and the cutting mechanism, the X-axis movement device, the Y-axis movement device, and the Z-axis movement device each include an instrumentation unit capable of measuring the amount of movement on each axis of the cutting mechanism; The cutting device, wherein the instrumentation unit is configured to be able to inject compressed gas thereto.

2. A cutting device for removing an object that obstructs the removal of spent fuel from a fuel storage rack that is composed of a plurality of rack cells, The device comprises a device body, a fixing mechanism, and a control unit, the device body has a moving mechanism and a cutting mechanism, the moving mechanism is configured to be able to move the cutting mechanism three-dimensionally, The cutting mechanism includes a cutting tool body and a camera unit capable of photographing a cutting target area of ​​the cutting tool body, the camera unit includes a plurality of camera bodies and a camera fixing unit; the camera fixing unit is configured to be able to change the arrangement of the plurality of camera bodies, the fixing mechanism is configured to be able to fix the device main body to the fuel storage rack, The control unit is configured to be able to remotely control the fixing mechanism, the moving mechanism, and the cutting mechanism.

3. A cutting device for removing an object that obstructs the removal of spent fuel from a fuel storage rack that is composed of a plurality of rack cells, The device comprises a device body, a fixing mechanism, and a control unit, the device body has a moving mechanism and a cutting mechanism, the moving mechanism is configured to be able to move the cutting mechanism three-dimensionally, and the cutting mechanism includes a cutting tool body; the fixing mechanism includes a plurality of main fixing devices that enable the device body to be fixed to the fuel storage rack; the control unit is configured to be able to remotely control the fixing mechanism, the moving mechanism, and the cutting mechanism, The cutting device, wherein the plurality of primary fixing devices are generally columnar bodies that can be inserted into the rack cells.

4. 4. The cutting device according to claim 1, wherein the cutting tool body is generally rod-shaped and configured to be capable of cutting in a direction generally perpendicular to its longitudinal direction.

5. 5. The cutting device according to claim 1, wherein the control unit is configured to be able to automatically control the movement mechanism and the cutting mechanism based on input cutting parameters.

6. 6. The cutting device according to claim 1, wherein the control unit is configured to be able to perform an incrementing operation on the movement mechanism.

7. 7. The cutting device according to claim 1, wherein the control unit is configured to automatically control the moving mechanism so that the cutting mechanism is located at the center of gravity of the device body.

8. The cutting device of claim 3 , wherein the plurality of primary fixation devices includes secondary fixation devices for fixing the primary fixation devices within the rack cells.

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