JPH11109083A - Upper lattice plate narrow part vt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an upper lattice plate narrow part VT device that can fully bring an underwater camera to an upper lattice plate narrow part being formed by a shroud and an upper lattice plate. SOLUTION: A VT device body 1 is installed on a shroud 20. The base-edge part of an operation arm 2 that can freely enter the shroud 20 is connected to the VT device body 1. A camera-mounted arm 3 that can freely enter an upper lattice plate narrow part 20n is rotatably connected to a tip part 2x of the operation arm 2. An underwater camera 4 for picking up the image of the inside of the upper lattice plate narrow part 20n is mounted to the camera-mounted arm 3. An image-processing device 5 for receiving an image from the underground camera 4 is connected to the underwater camera 4. An angle-adjusting mechanism 6 for adjusting the connection angle between both arms 2 and 3 is connected between the operation arm 2 and the camera-mounted arm 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactor installed in a reactor having an upper lattice plate and a shroud forming an upper lattice plate narrow portion, and for observing and inspecting the upper lattice plate and the shroud. It relates to a VT device.

[0002]

2. Description of the Related Art In general, the internal structural members of a boiling water reactor need to be made of a material having sufficient corrosion resistance and strength in high-temperature and high-pressure water. Steel or a nickel-based alloy is used.

[0003] Replaceable furnace structural members can be maintained by replacing them with new members in consideration of material deterioration due to prolonged exposure to a high-temperature, high-pressure environment. However, it is an issue how to deal with material deterioration of non-replaceable in-furnace structural members due to prolonged exposure to a high-temperature, high-pressure environment.

[0004] Fuel support members such as an upper lattice plate and a shroud are further subjected to neutron irradiation under a severe environment of high temperature and high pressure water. Reactor water flows from the upper part to the lower part outside the upper lattice plate and the shroud, and reactor water flows from the lower part to the upper part inside. For this reason, those fluid pressures give stress to the fuel support member.
Therefore, it is considered that these structural members are particularly fast in material deterioration. Furthermore, the welded part of the furnace internals,
Potential stress corrosion cracking has also been pointed out due to the sensitization and residual stress of the material due to heat input during welding.

[0005] As a technique for maintaining non-replaceable in-furnace structural members, a surface modification technique for in-furnace structural members has been developed. In order to use such a surface modification technique, it is necessary to check the surface condition of the furnace internal structure in advance.

FIG. 8 is a diagram showing a conventional VT device for checking the surface condition of the furnace internals. As shown in FIG. 8, a conventional VT device 50 includes a VT device main body 51 and a VT device.
A wire rope 52 having a base end connected to the apparatus main body 51 and suspended in the reactor pressure vessel 31;
The underwater camera 53 and the underwater illuminator 54 mounted on the front end of the camera 2 and a display television 51a connected to the underwater camera 53 and receiving an image from the underwater camera 53.

On the other hand, as shown in FIG. 8, a shroud 20 is generally housed in a reactor pressure vessel 31, and the shroud 20 is composed of an upper shell 20a, an intermediate shell 20b, and a lower shell 2
0c. An upper lattice plate 32 is provided on the upper inside of the upper shell 20 a of the shroud 20, and the lower surface of the lower shell 20 c of the shroud 20 is supported by a core support plate 33. A jet pump 34 is provided in the reactor pressure vessel 31 in addition to the shroud 20.

In the conventional VT device 50, as shown in FIG. 8, the upper cover (not shown) of the reactor pressure vessel 31 is removed, and the VT device main body 51 is installed on the operation floor 35 above the shroud 20, and a wire is provided. A rope 52 is used by being suspended in the reactor pressure vessel 31.

The conventional VT device 50 includes a wire rope 52
The underwater camera 53 mounted on the tip of the shroud 20 and the inner and outer surfaces of the shroud 20 in the reactor pressure vessel 31 and the upper grid plate 32
Of the outer surface of the camera. The image captured by the underwater camera 53 is projected on the image television 51a. The test diagnostician diagnoses the image projected on the display television 51a with the naked eye, and if necessary, performs a penetrant inspection test, an ultrasonic inspection test, or the like.

As another VT device, an underwater swimming type camera robot in which an underwater camera freely swims has been proposed.

[0011]

However, in the above-mentioned conventional VT device 50 and the underwater swimming type camera robot, the narrow portion in the reactor pressure vessel 31, especially the shroud 2
There is a problem that it is difficult to bring the camera close to the upper lattice plate narrow portion 20n formed by the upper lattice plate 32 and the upper lattice plate 32, and a detailed image of this portion cannot be obtained. Further, since the welded portions of the shroud 20 and the upper lattice plate 32 are also generally narrow, it is not possible to obtain a more detailed image by bringing the camera closer.

The present invention has been made in view of the above points, and an upper lattice plate that allows an underwater camera to be sufficiently close to a narrow portion of an upper lattice plate formed by a shroud and an upper lattice plate. It is an object to provide a narrow section VT device.

[0013]

SUMMARY OF THE INVENTION The present invention relates to an upper grid plate narrow section VT apparatus installed in a reactor having an upper grid plate forming a narrow section of an upper grid plate and a shroud.
A VT device main body installed on the shroud, a base end connected to the VT device main body, an operation arm that can freely enter the inside of the shroud, and rotatably connected to a distal end portion of the operation arm;
A camera mounting arm that can freely enter the narrow part of the upper lattice plate,
An underwater camera mounted on the camera mounting arm and imaging the narrow part of the upper lattice plate, and connected to the underwater camera,
An upper lattice, comprising: an image processing device that receives an image from an underwater camera; and an angle adjustment mechanism that is interposed between an operation arm and a camera mounting arm and that adjusts a connection angle between the two arms. This is a VT device with a narrow plate.

According to the present invention, the camera mounting arm can be inserted into the narrow portion of the upper lattice plate by adjusting the connection angle of the camera mounting arm with respect to the operation arm by the angle adjusting mechanism.

The present invention also relates to a VT device having an upper lattice plate narrow portion which is installed in a reactor having an upper lattice plate forming a narrow portion of the upper lattice plate and a shroud. A base end is connected to the apparatus main body, and an operation arm that can enter into the shroud, a camera mounting arm that is connected to a distal end of the operation arm, and that can enter into the narrow portion of the upper lattice plate, and are mounted on the camera mounting arm. An underwater camera that captures the inside of the narrow portion of the upper lattice plate, and an image processing device that is connected to the underwater camera and receives an image from the underwater camera, and moves the operation arm along the top of the shroud to the top of the shroud An upper lattice plate narrow portion VT characterized by having a moving mechanism.
Device.

According to the present invention, since the operating arm is moved along the upper end of the shroud by the moving mechanism, the camera mounting arm connected to the operating arm and having the underwater camera mounted thereon can also move in the circumferential direction along the shroud wall surface. Yes, the movement of the camera mounting arm is not hindered by the shroud wall.

The present invention also relates to a VT device having a narrow upper lattice plate forming a narrow portion of an upper lattice plate and a shroud, wherein the VT device main body is provided on a shroud; A base end is connected to the apparatus main body, and an operation arm that can enter into the shroud, a camera mounting arm that is connected to a distal end of the operation arm, and that can enter into the narrow portion of the upper lattice plate, and are mounted on the camera mounting arm. An underwater camera that captures an image inside the narrow portion of the upper lattice plate, and an image processing device that is connected to the underwater camera and receives an image from the underwater camera, the operation arm includes at least a pair of arm members that slide with respect to each other. A pair of arm members slidably moved by a driving mechanism to extend and retract the operation arm, wherein the upper lattice plate narrow portion VT is provided.
Device.

According to the present invention, since the operation arm is expanded and contracted by the pair of arm members, the camera mounting arm connected to the operation arm and mounting the underwater camera can move up and down along the shroud wall surface. The movement of the camera mounting arm is not hindered by the shroud wall.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

First, referring to FIGS. 5 to 7, a boiling water reactor (BWR) 30 in which the narrow VT device 10 according to the present invention is used will be described. Boiling water reactor 3
0 is a reactor pressure vessel (RPV) 3 as shown in FIG.
1 houses a cylindrical shroud 20. The shroud 20 is supported and erected on a shroud support leg 21 installed in a reactor pressure vessel 31.

In the shroud 20, a core 41 on which the fuel assemblies 40 are loaded is disposed. At the bottom of the reactor pressure vessel 31, a control rod drive mechanism (CRD) housing 42h is provided.
The lower end of the control rod guide tube 42g is connected to h.
A fuel assembly support bracket (not shown) is incorporated at the upper end of the control rod guide tube 42g. Control rod guide tube 42
The control rod 42 is provided so as to be freely inserted into and removed from the reactor core 41 through the g.

The upper part of the fuel assembly 40 is an upper lattice plate 32.
, And a lower portion thereof is supported by a fuel assembly support bracket and is loaded in the core 41. One fuel assembly support bracket supports four fuel assemblies. The fuel assembly 40 is supported laterally by the core support plate 32.

A shroud head 22 is provided above the shroud 20, a steam-water separator 24a is provided above the shroud head 22 via a standpipe 23, and a steam drying unit is provided above the steam-water separator 24a. Vessel 24b
Is provided.

In addition, a plurality of jet pumps 8 are provided at predetermined intervals in the circumferential direction in an annular gap between the inner peripheral surface of the reactor pressure vessel 31 and the outer peripheral surface of the shroud 20. Further, between the shroud 20 and the upper lattice plate 32, an upper lattice plate narrow portion 20n is formed.

Next, referring to FIG. 1 and FIG. 2, a first embodiment of the upper lattice plate narrow portion VT device according to the present invention will be described. As shown in FIG. 1 and FIG. 2, an upper lattice plate narrow portion VT device 10 according to the present invention includes a VT device main body 1 provided on a shroud 20 forming an upper lattice plate narrow portion 20n.
It has. The VT device body 1 has a shroud 2
An operation arm 2 that can enter the inside of the operation arm 2 is connected to the lower end 2x of the operation arm 2. A camera mounting arm 3 that can enter the upper lattice plate narrow portion 20n is rotatably connected by a pin member 2p. .

An underwater camera 4 and an underwater illuminator 7 are mounted on the camera mounting arm 3, and the upper lattice plate narrow portion 2
0n can be imaged. The underwater camera 4 is connected to an image processing device 5 that receives an image from the underwater camera 4.

As shown in FIGS. 2A and 2B, the operation arm 2 is a pair of upper and lower arm members 2a and 2b which slide with respect to each other.
And a bent portion 2c that is bent and connected to the lower arm member 2b at an obtuse angle, and the lower end 2x described above is located at the lower end of the bent portion 2c. The operation arm 2 has a V at an upper arm member 2a (a base end of the operation arm 2).
It is connected to the T device main body 1. The camera mounting arm 3 has a camera mounting portion 3a connected to the lower end 2x of the operation arm 2 and a bent portion 3b that can be seen to overlap the bent portion 2c of the operation arm 2 in FIG. Further, a cylinder mounting portion 3c is provided at an upper end of the bent portion 3b.

Between the operation arm 2 and the camera mounting arm 3, an angle adjusting mechanism 6 for adjusting the connection angle between the two arms 2, 3 is interposed. The angle adjusting mechanism 6 includes a side portion 2s of the operation arm 2 and a cylinder mounting portion 3 of the camera mounting arm 3.
and the angle adjusting cylinders 6a and 6b connected to the cylinders c and c. When the angle adjusting cylinders 6a and 6b are shortened, the bent portion 2c of the operation arm 2 and the bent portion 3b of the camera mounting arm 3 are overlapped. At this time, the operation arm 2 and the camera mounting portion 3a Become parallel (see FIG. 1). When the angle adjusting cylinders 6a and 6b are extended, the bent portion 2c of the operation arm 2 and the camera mounting portion 3a of the camera mounting arm 3 are in a straight line (FIG. 2A).
(B)).

The operating arm 2 has a pair of upper and lower arm members 2a and 2b which slide with each other as described above, and the lower arm member 2b is moved by an upper and lower cylinder 2m as an up and down driving mechanism. It is slidable with respect to the member 2a. That is, the operation arm 2 expands and contracts by the relative movement of the pair of upper and lower arm members 2a and 2b,
When the upper arm member 2a is fixed, the lower arm member 2b can move up and down.

The image processing device 5 is installed in the VT device main body 1, but may be a normal display television or a device capable of executing an image processing program.

Next, referring to FIGS. 1, 6 and 7, the support mechanism of the VT device main body 1 and the operation arm 2 will be described. Here, FIG. 6 is an enlarged view of an upper lattice plate narrow portion 20n formed by the shroud 20 and the upper lattice plate 32, and FIG. 7 is a plan view thereof. As shown in FIG. 6, an intermediate ring 20 m and a cylindrical upper shroud body 20 a are welded and fixed to the upper end of the shroud 20 concentrically with the shroud 20. A core sparger 25 is provided on the inner periphery of the upper shroud body 20a. An upper ring 20u and a rail ring 20r are further provided integrally and concentrically with the shroud 20 at the upper end of the upper shroud body 20a.

As shown in FIGS. 6 and 7, twelve pedestals 20s are provided at predetermined intervals in the circumferential direction on the intermediate ring 20m, and the upper lattice plate 32 is disposed on these pedestals 20s. I have. A plurality of brackets 26a protruding inward are provided on the inner peripheral surface of the shroud upper body 20a.
And wedges 26b are provided at predetermined intervals in the circumferential direction in two upper and lower stages.

On the other hand, as shown in FIG.
A plurality of wedges 27 projecting outward and abutting the wedges 26b are arranged at predetermined intervals on the outer peripheral surface of the. For this reason, the upper lattice plate 32 is prevented from shifting in the circumferential direction. A plurality of bottom wedges 32k are arranged at predetermined intervals in the circumferential direction at the bottom of the upper lattice plate 32. For this reason, an intermediate portion between the adjacent bottom wedges 32k is an opening 32s communicating the upper lattice plate narrow portion 20n and the inside of the shroud 20.

As shown in FIG. 1, a moving mechanism 11 for moving the VT device body 1 and the operation arm 2 along the upper end of the rail ring 20r at the upper end of the shroud is provided on a rail ring 20r provided at the upper end of the shroud. ing. The moving mechanism 11 includes a moving roller 11r that rolls along the upper end of the rail ring 20r at the upper end of the shroud 20.
And a guide 11g supported by the moving roller 11r and holding the upper arm member 2a of the operation arm 2, and a turning motor 11m for driving the moving roller 11r. The turning motor 11m is also held by the guide 11g. Also, the guide 11g is a rail ring 20.
It has an engaging portion 11e that slidably engages with the r. In addition, the engaging portion 11 of the moving roller 11r and the guide 11g
e indicates the rail ring 20 when the camera mounting portion 3a of the camera mounting arm 3 is located within the upper lattice plate narrow portion 20n.
It is arranged to abut and engage with r.

Further, an auxiliary moving mechanism 13 is provided on the arm member 2b below the narrow portion VT device 10 of the upper lattice plate. The auxiliary moving mechanism 13 includes an auxiliary roller 13r that rolls along the inner peripheral surface of the upper ring 20u, and an auxiliary roller 13r.
and an auxiliary motor 13m for driving r.

Next, the operation of the present embodiment having the above configuration will be described. First, the operation arm 2 is suspended in the shroud 20. Initially, the angle adjusting cylinders 6a and 6b maintain the shortened state, and therefore, the bent portion 2c of the operation arm 2 and the bent portion 3b of the camera mounting arm 3
And the operation arm 2 and the camera mounting portion 3a are kept parallel to each other.

When the camera mounting portion 3a of the camera mounting arm 3 approaches the upper lattice plate narrow portion 20n, the angle adjusting cylinders 6a and 6b are extended as shown in FIG.
The bent portion 2c of the operation arm 2 and the camera mounting portion 3a of the camera mounting arm 3 are made straight. In this state, the camera mounting part 3 of the camera mounting arm
Insert a. As shown in FIG. 2, when a core sparger 25 exists above the narrow portion 20 n of the upper lattice plate, the angle adjusting cylinder 6 a is provided so that the camera mounting arm 3 does not interfere with the core sparger 25.
Adjust 6b.

As shown in FIG. 2B, when the pin member 2p that supports the operation arm 2 and the camera mounting arm 3 enters the upper lattice plate narrow portion 20n, the angle adjusting cylinder 6
a, 6b are shortened. As a result, the operation arm 2 and the camera mounting unit 3a return to the parallel state.

Next, the position of the operating arm 2 is adjusted, and the engaging portion 11e of the guide 11g is engaged with the upper end of the rail ring 20r. At this time, the moving roller 11r contacts the upper end of the rail ring 20r. At the same time, the auxiliary roller 1
3r is in contact with the inner peripheral surface of the upper ring 20u.

From this state, the underwater camera 4 mounted on the camera mounting arm 3 starts imaging. The image captured by the underwater camera 4 is transmitted to the image processing device 5. If the image processing device 5 that receives the image is a normal display television, the test diagnosing person diagnoses the situation by looking at the image with the naked eye. If the image processing device 5 is a device that can execute an image processing program, a situation diagnosis is automatically performed.

Next, the operation arm 2 to which the camera mounting arm 3 is connected is moved while the imaging by the underwater camera 4 is continued. In the circumferential direction, the operation arm 2 supported by the moving roller 11r can be moved by rolling the moving roller 11r along the upper end of the rail ring 20r at the upper end of the shroud 20. At this time, guide 11
The engaging portion 11e of g guides the movement trajectory. Moving roller 1
1r is driven by a turning motor 11m. Also, the auxiliary roller 13 is assisted by the auxiliary motor 13m.
By driving the auxiliary roller 13r with respect to the inner peripheral surface of the upper ring 20u, the operation arm 2 can be moved more smoothly.

Although the upper lattice plate narrow portion 20n is formed in an annular shape, since the operation arm 2 moves along the upper end of the rail ring 20r, the camera mounting arm connected to the operation arm 2 and mounting the underwater camera 4 is provided. 3 also shroud 20
, And the movement of the camera mounting arm 3 is not hindered by the shroud 20.

The vertical movement of the camera mounting arm 3 is as follows.
This is performed by driving the vertical cylinder 2m to slide the lower arm member 2b with respect to the upper arm member 2a. Therefore, the camera mounting arm 3 can be moved up and down without affecting the relationship between the moving mechanism 11 provided on the upper arm member 2a and the rail ring 20r.

By the movement of the camera mounting arm 3 as described above, the inside of the narrow portion of the upper lattice plate 20n can be imaged in a short distance and without fail.

As described above, according to the present embodiment, since the connection angle of the camera mounting arm 3 with respect to the operation arm 2 can be adjusted by the angle adjusting mechanism 6, the camera mounting arm 3 is inserted into the upper lattice plate narrow portion 20n. It is possible. Further, since the operation arm 2 is moved along the shroud 20 by the moving mechanism 11, the camera mounting arm 3 connected to the operation arm 2 and mounted with the underwater camera 4 can also move in the circumferential direction along the wall surface of the shroud 20. Therefore, the movement of the camera mounting arm 3 is not hindered by the shroud wall surface. Further, since the operation arm 2 is expanded and contracted by the pair of arm members 2a and 2b, the camera mounting arm 3 connected to the operation arm 2 and mounting the underwater camera 4 can also move up and down along the shroud 20 wall surface. The movement of the camera mounting arm 3 is not hindered by the shroud 20 wall surface.

Next, with reference to FIG. 3, a description will be given of a second embodiment of the narrow portion VT device of the upper lattice plate according to the present invention.
An upper lattice plate narrow portion V according to the second embodiment shown in FIG.
The T device 60 includes the operation arm 2 and the camera mounting arm 3
1 is different from that of FIG. 1 and FIG.
Is substantially the same as the first embodiment shown in FIG. In FIG. 3, the same portions as those of the first embodiment shown in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 3, the upper lattice plate narrow portion VT
The device 60 includes an operation arm 62 having a pair of arm members 62a and 62b, and a camera mounting arm 63. The arm member 62b below the operation arm 62 is linear. A shaft gear portion 62s is formed on the lower arm member 62b, and a nut 66n is engaged with the shaft gear portion 62s. Shaft gear part 62s
Is connected to a shaft rotation motor 66 via a transmission gear 66g.
m is connected, and the shaft gear 62s is rotated by driving the shaft rotation motor 66m. When the shaft gear portion 62s rotates, the nut 66n moves up and down according to the rotation direction.

Further, as shown in FIG.
The camera mounting arm 63 of the T device 60 has a straight portion 63b and a bent portion 63a bent at an obtuse angle, and the underwater camera 4 is mounted on the bent portion 63a. Straight section 6
3b is fixed to the nut 66n, so that the camera mounting arm 3 moves up and down following the up and down movement of the nut 66n.

The upper lattice plate narrow portion VT device 60 according to the second embodiment shown in FIG. 3 includes an angle adjustment mechanism 6 for adjusting the angle between the operation arm 2 and the camera mounting arm 3;
Although no auxiliary moving mechanism 13 is provided, these mechanisms may be provided in the second embodiment.

The VT device 60 for the narrow portion of the upper lattice plate shown in FIG.
According to this, only the camera mounting arm 3 can be moved up and down, and the vertical position adjustment of the underwater camera 4 within the upper lattice plate narrow portion 20n is easy. Therefore, it is particularly effective when imaging a vertical welding line portion.

Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment shown in FIG.
And narrow portion VT of upper lattice plate in second embodiment
In the devices 10 and 60, the operation arms 2 and 62
Is connected to a gripping arm 70 having a gripping tool 71. FIG. 4 is a sectional view of the gripping arm 70 connected to the operation arms 2 and 62. As shown in FIG. 4, a joint 73 for connecting to the operation arms 2 and 62 is formed at the base end of the gripping arm 70, and the joint 73 has a case 7.
4 is connected, and the cylinder 72 is housed in the case 74. A moving rod 75 is connected to the cylinder 72, and the moving rod 75 penetrates the case 74,
A gripping tool 71 is formed at the tip. The cylinder 72 can be remotely operated. The grip 71 is the ring 7
1h and a claw member 71c.
Is moved up and down to move the claw member 71c to the ring portion 71h.
You can get in and out of. For this reason, the claw member 71c
Opening and closing operation can be obtained. The moving rod 75 is attached to the cylinder 7
2 is driven up and down.

By using the gripping arm 70 shown in FIG. 4, it is possible to grasp and remove the foreign matter in the upper lattice plate narrow portion 20n together with the imaging of the upper lattice plate narrow portion 20n.

[0053]

As described above, according to the present invention, the camera mounting arm can be inserted into the narrow portion of the upper lattice plate by adjusting the connection angle of the camera mounting arm with respect to the operation arm by the angle adjusting mechanism. is there. Therefore, it is possible to take an image of the inside of the narrow portion of the upper lattice plate in a short distance and in detail.

Further, according to the present invention, since the operating arm is moved along the upper end of the shroud by the moving mechanism, the camera mounting arm connected to the operating arm and mounted with the underwater camera is also moved circumferentially along the shroud wall surface. The movement of the camera mounting arm is not hindered by the shroud wall.

According to the present invention, since the operation arm is extended and contracted by the pair of arm members, the camera mounting arm connected to the operation arm and mounted with the underwater camera can also move up and down along the shroud wall surface. The movement of the camera mounting arm is not hindered by the shroud wall.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an upper lattice plate narrow portion VT device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a state in which a camera mounting arm is inserted into a narrow portion of an upper lattice plate in the first embodiment of the present invention.

FIG. 3 is a schematic sectional view showing an upper lattice plate narrow portion VT device according to a second embodiment of the present invention.

FIG. 4 is a schematic sectional view showing a gripping arm according to a third embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view illustrating a peripheral portion of a shroud and an upper lattice plate.

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a schematic sectional view of a boiling water reactor.

FIG. 8 is a schematic sectional view showing a conventional VT device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 VT apparatus main body 2 Operation arm 2a Upper arm member 2b Lower arm member 2x Operation arm lower end part 2m Vertical cylinder 3 Camera mounting arm 4 Underwater camera 5 Image processing device 6 Angle adjustment mechanism 6a cylinder 6b cylinder 7 Underwater lighting fixture 10 Upper part Lattice plate narrow part VT device 11 Moving mechanism 11m Rotating movement motor 11r Moving roller 11g Guide 20 Shroud 20n Upper lattice plate narrow part 30 Boiling water reactor 32 Upper lattice plate 50 VT device 51 VT device body 51a Display TV 52 Wire rope 53 Underwater Camera 54 Underwater Lighting Tool 60 Upper Lattice Plate Narrow Section VT Device 62 Operation Arm 62b Lower Arm Member 63 Camera Arm 70 Holding Arm 71 Holding Tool

Claims (7)

[Claims] An upper lattice plate narrow portion VT device installed in a nuclear reactor having an upper lattice plate forming a narrow portion of an upper lattice plate and a shroud, wherein a VT device main body installed on the shroud; A base end is connected, an operation arm that can enter the shroud freely, and a camera mounting arm that is rotatably connected to the distal end of the operation arm and that can enter the narrow portion of the upper lattice plate, and is mounted on the camera mounting arm. And an underwater camera connected to the underwater camera to receive images from the underwater camera; an image processing device connected to the underwater camera and interposed between the operation arm and the camera mounting arm; And an angle adjusting mechanism for adjusting a connection angle. 2. The VT device according to claim 1, wherein the angle adjusting mechanism comprises an angle adjusting cylinder connected to the operation arm and the camera mounting arm. 3. An VT device having an upper lattice plate narrow portion which is installed in a reactor having an upper lattice plate and a shroud forming an upper lattice plate narrow portion, comprising: a VT device main body installed on the shroud; An operation arm connected to the base end and freely entering the shroud, a camera mounting arm connected to the distal end of the operation arm and freely entering the upper lattice plate narrow part, and an upper lattice mounted on the camera mounting arm An underwater camera that captures an image of the inside of the narrow board, and an image processing device that is connected to the underwater camera and receives an image from the underwater camera. A moving mechanism that moves the operation arm along the upper end of the shroud at the upper end of the shroud. An upper lattice plate narrow portion VT device provided. 4. A moving mechanism comprising: a moving roller rolling along an upper end of a shroud; a guide supported by the moving roller and holding an operation arm; and a turning motor for driving the moving roller. The narrow portion VT of the upper lattice plate according to claim 3, characterized in that:
apparatus. 5. A narrow VT device for an upper lattice plate installed in a reactor having an upper lattice plate and a shroud forming an upper lattice plate narrow portion, wherein a VT device main body installed on the shroud, and a VT device main body. An operation arm connected to the base end and freely entering the shroud, a camera mounting arm connected to the distal end of the operation arm and freely entering the upper lattice plate narrow part, and an upper lattice mounted on the camera mounting arm An underwater camera that captures an image of the inside of the narrow plate, and an image processing device that is connected to the underwater camera and receives an image from the underwater camera, includes an operation arm including at least one pair of arm members that slide with respect to each other. An upper lattice plate narrow portion VT device, wherein the arm members slide with respect to each other by a drive mechanism to expand and contract the operation arm. 6. The VT device according to claim 1, wherein a gripping arm having a gripping tool is connected to the operation arm. 7. The VT device according to claim 1, wherein an underwater lighting device is provided on the camera mounting arm.