JP3485984B2 - Furnace inspection system and furnace inspection method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for inspecting a reactor pressure vessel and a method for inspecting the same, and particularly to inspecting welding lines on inner and outer walls of a reactor pressure vessel of a light water cooling type reactor and reactor internal structures. and an inspection method of a furnace inspection system and its for inspecting.

[0002]

2. Description of the Related Art A fuel assembly, a reactor internal structure, a control rod, a steam separator, a steam dryer, a core spray sparger, etc. are usually installed in a reactor pressure vessel of a boiling water reactor. However, when inspecting and inspecting the reactor pressure vessel, the shroud head and other equipment of the structure fixed in the reactor pressure vessel are removed.

The internal structure of the reactor comprises a shroud forming an internal tank, a shroud head, a core support plate for laterally supporting the core, and an upper lattice plate. The shroud consists of an upper shell, a middle shell, and a lower shell. The lower shell is supported by a welded structure on a shroud support that is made integral with the reactor pressure vessel. A jet pump is installed in the annulus space between the reactor pressure vessel and the shroud.

Conventionally, when performing visual inspection (hereinafter referred to as UV inspection) or ultrasonic flaw detection test inspection (hereinafter referred to as UT inspection) of the welding line on the inner wall of the reactor pressure vessel or the inner and outer walls of the shroud, the inspection target or Dedicated inspection equipment was installed according to the inspection location, and individual inspection was performed.

For example, in the case of an inner wall of a reactor pressure vessel, an arm that moves in the circumferential direction around a dedicated guide installed on the upper end of the shroud upper shell or the inner wall of the reactor pressure vessel and expands and contracts between the adjacent jet pumps of the annulus portion, There is a device for performing inspection by lowering a VT inspection camera or a UT probe by a guide. This scans vertically or circumferentially within the allowable range between the jet pumps, and the horizontal extension mechanism is extended between the jet pumps and the inner wall of the reactor pressure vessel for scanning.

Since the jet pump and the inner wall of the reactor pressure vessel are connected by the riser brace and the elbow of the jet pump riser pipe, it is impossible to move in the circumferential direction with the guides and arms that move up and down in the vertical direction extended. is there. Therefore, in order to move in the circumferential direction, each time it is necessary to contract upward and avoid them.

Also, the outer wall of the shroud is moved in the circumferential direction with the upper end portion of the upper shell of the shroud as a track, similarly to the inner wall of the reactor pressure vessel, and for the VT inspection by the arms and guides that expand and contract between the adjacent jet pumps of the annulus portion. There is known a device for inspecting by lowering a camera or a UT probe.

In this device, an inspection unit is attached to the tip of an arm in a state where thin plates are connected, and the jet pump riser brace or riser bracket is moved to move in the circumferential direction. Therefore, the arm is used to avoid the gap between the jet pump and the outer wall of the shroud. There is no need to raise and lower. However,
The part that can be inspected is the welding line of the shroud middle part,
Not applicable to weld lines on shroud lower shell.

Further, in the inner wall of the shroud, there is an upper grid plate when inspecting the welding line of the intermediate body, and it cannot move in the circumferential direction like the above-mentioned two places. Therefore, the inspection device is provided at the tip of the operation pole. There is known a device which is attached to the shroud through the upper lattice plate, fixed and fixed to the inner wall of the shroud to inspect by the scanning degree of freedom of the inspection device body.

In such a device, in order to move the inspection device in the circumferential direction, the inspection device must be lifted and moved above the upper lattice plate each time. Further, there is also known an inspection device in which a vertical welding line is sucked and fixed on an inspection surface and the inspection unit is scanned by a moving mechanism in the vertical direction.

[0011]

In a device such as a device for inspecting the inner wall of a reactor pressure vessel, in which the elevating guide and the arm must be extended and contracted by bypassing the jet pump, one round is required for the inspection of the horizontal welding line. You have to avoid the jet pump and move it up and down at least 10 times, so
There is a drawback that the inspection time is increased and, for example, the regular inspection work process is not shortened.

Further, in a device installed and moved by using an operation pole such as a device for inspecting the inner wall of the shroud, in order to move the shroud in the circumferential direction, the device must be lifted above the upper lattice plate. There is a drawback that it increases and does not lead to shortening of the regular inspection work process.

Further, the operation pole is long, and the weight of the pole itself is large, which makes it difficult to handle.
It is necessary to handle the previous inspection device for more than 20 m, and there is a drawback that the pole is bent due to the viscosity of water and the visibility is poor and the workability is extremely poor.

In order to carry out such an inspection work, the worker is required to have the skill, and it is necessary to sufficiently perform the training, and there is a problem that the skill must be secured. Especially when working on the lower shroud body, the working environment becomes considerably worse,
Work becomes difficult.

As described above, the number of inspection devices increases in an in-furnace inspection system in which a device corresponding to each inspected part is prepared and the work is performed individually, and the entire system is required to inspect all parts. However, in addition to the large scale and complexity, an operator for each device is also required for each device, which causes a problem of high cost.

In an apparatus for inspecting the inner wall of the reactor pressure vessel and the outer wall of the shroud, when both circumferential guides are provided at the upper end of the upper shroud shell, a plurality of in-reactor inspection apparatuses cannot be installed at the same time. There is a drawback that work cannot be performed in parallel, and the number of regular inspection work steps increases, for example. Also, since it is almost impossible to proceed with the inspection of the inner surface of the shroud in parallel at the same time, the work period becomes longer,
For example, there is a problem that the regular inspection work process increases.

The present invention has been made to solve the above-mentioned problems, and handles VT inspection and UT inspection of each welding line of the inner wall of the reactor pressure vessel and the inner and outer walls of the shroud automatically and remotely to handle the in-reactor inspection device. The work load and skill of workers are reduced to improve work efficiency and reduce the radiation exposure during work, and each in-core inspection device is not prepared for each inspection object. It is possible to perform universally in, installation of the in-furnace inspecting device, and less work time required for inspection, for example, in-reactor inspecting system and its inspecting device and position detecting device and its To provide an inspection method.

[0018]

The invention according to claim 1 of the present invention (hereinafter referred to as the first invention) includes an inner wall of a reactor pressure vessel of a light water cooling type reactor, an upper shell, an intermediate shell and a lower shell.
In-reactor inspection system that inspects the inner and outer walls of the shroud
In, the reactor pressure vessel inner wall and the shroud outer wall
Jet pump installed between the reactor and the reactor pressure vessel
Between the inner walls, the jet pump and the shroud outer wall
Mounted on the upper shell of the shroud
The upper grid plate and the shroud intermediate cylinder lower part
Can be passed through the holes in the core support plate
After touching the inspection target area after moving to
In-furnace inspector for scanning and placed on top of the shroud
Inside the furnace provided on the rotatable turntable
A position detection device that detects the position of the device and controls travel,
Control unit for controlling the position detecting device of the above, and the position detecting device
And an operating unit for operating the.

The invention according to claim 2 of the present invention (hereinafter referred to as the second
Of the invention), the in- furnace inspection device propels the inside of the furnace.
And because of the propulsion unit, a suction unit for contacting the test object, a moving mechanism for moving the upper inspected, inspection pairs
Features and inspection sensor for inspecting an elephant sites, a scanning mechanism for scanning the test sensor, by comprising a laser beam reflector for detecting the position of the front Symbol furnace inspection apparatus main body tracking And

The invention according to claim 3 of the present invention (hereinafter referred to as the third
Of the invention) is provided in the main body of the inspection device in the furnace.
To detect the inclination of the illuminant and the main body of the in-furnace inspection device
And an inclination angle detection unit .

The invention according to claim 4 of the present invention (hereinafter referred to as the fourth
Of the invention), the suction portion is a motor shaft of the propulsion unit.
The adsorption chamber that can move in parallel with the
And a blade attached to the tip .

The invention according to claim 5 of the present invention (hereinafter referred to as the fifth
Invention), the propulsion device is a motor and
It consists of the attached propeller and the inside of the reactor pressure vessel.
Up-down, left-right, forward-backward translation and vertical axis relative to the face
A machine that gives freedom of movement around and around the normal axis
It is characterized by being attached to the structure .

The invention according to claim 6 of the present invention (hereinafter referred to as the sixth
Invention), the moving mechanism has at least two drive units.
It is composed of moving wheels, and the traveling direction is up and down and left and right
Each wheel rotation shaft is configured so that it can be freely turned.
Characterized in that it comprises Te.

The invention according to claim 7 of the present invention (hereinafter referred to as the seventh aspect)
The invention of) is applied to the contact surface of the inspection sensor.
Adjustable angle of the moving mechanism, propulsion unit and suction unit
It is characterized in that it is configured in .

The invention according to claim 8 of the present invention (hereinafter referred to as the eighth
Invention)), the inspection sensor is installed in the furnace inspection device.
The present invention is characterized in that a scanning mechanism that operates and scans in the main body is provided .

The invention according to claim 9 of the present invention (hereinafter referred to as the ninth
Invention)) , a support wheel is attached to the main body of the in-core inspection device.
It is characterized by being provided .

[0027]

[0028]

The invention described in claim 10 of the present invention (hereinafter the 10
Invention)), the position detection device is a laser light projection.
It is characterized by having a light receiving portion and a tracking position detecting portion .

[0030]

[0031]

The invention according to claim 11 of the present invention (hereinafter referred to as the 11th invention)
Invention)), the position detecting device is
Emitting light emitting element and reflecting from this light emitting element
Laser light reception and reception equipped with a light receiving element that receives laser light
The optical part and the laser light which exceeds the arbitrary receiving level of the laser light
A light receiving detection circuit that detects only the emitted light, and the laser light
Measure the time from light emission to detection of light reception and convert it to distance
Rangefinder and laser light reflection that reflects the laser light
The plate and the reflected light from this laser light reflector are detected and
Measures the time from the projection of the laser light to the reflection and detection
Then, convert it into a distance and measure the position of the in-core inspection device body.
And a tracking position detection unit .

The invention according to claim 12 of the present invention (hereinafter referred to as the 12th invention)
Of the invention), the tracking position detection unit is
A TV monitor that projects the light emitted from the light emitters provided on the inspection device body.
The image that captures the video shot by this TV camera.
The image input device and the image processing device connected to the image input device.
It is characterized by consisting of

[0034]

The invention according to claim 13 of the present invention (hereinafter referred to as the thirteenth aspect)
Invention)) using an in- core inspection system to cool light water
Of the reactor pressure vessel inner wall and shroud inner and outer walls
A method for conducting an inspection, comprising:
Move the inside of the power container to move it to the vicinity of the inspection target
After the movement of the
Scannable and rotatable on top of the shroud
Attached to a rotating table
The furnace is detected by a position detection device that detects the
The inspection is performed while detecting the position of the internal inspection device .

[0036]

[0037]

[Action]

(First Invention) A first invention is an in-reactor inspection system for performing VT and UT work on an inner wall of a reactor pressure vessel and an inner and outer wall of a shroud of a light water cooling type reactor, wherein an in-reactor inspection device is a jet pump and a reactor. It can pass between the inner wall of the pressure vessel and between the outer wall of the jet pump and the outer wall of the shroud, and has an outer size that allows the lattice of the upper lattice plate and the holes of the core support plate to pass through. The inspection sensor is scanned along the weld line by contacting the target site.

The in-furnace inspection device is controlled by the control panel and operated by the operation panel. The position detection device is installed on the upper part of the shroud upper body for detecting the position of the in-core inspection device and controlling traveling. Therefore, the traveling control is performed while grasping the position of the in-core inspection device by the position detection device,
Perform VT and UT inspection of each welding line.

(Second invention) In the in-furnace inspection system, the in-furnace inspecting apparatus is a propulsion device for swimming movement, a suction section for adsorbing the in-reactor inspecting apparatus main body to the inspected object, and keeping the inspected object in contact. Moving mechanism to move, VT work and UT
An inspection sensor for performing work, a scanning mechanism for operating and scanning the inspection sensor with respect to the in-core inspection apparatus body, a laser light reflection plate for detecting and tracking the position of the in-core inspection apparatus, and the inside of the furnace An inclination angle detection unit for detecting the inclination of the inspection apparatus body.

It is possible to approach the object to be inspected while swimming by the propulsion device and further press the in-furnace inspection apparatus main body until it comes into contact with the object to be inspected. And, when fixing the in-furnace inspection device body, it is sucked and fixed by the suction part,
The inspection sensor is scanned by the scanning mechanism. When the main body of the apparatus is not fixed, the moving mechanism moves along the welding line while scanning the inspection sensor while being in contact with the inspection object.

The laser light is reflected by the laser light reflection plate, and the position detecting device measures and tracks the position of the in-core inspection device main body, and detects the position of the inspection device main body together with the inclination angle from the inclination angle detection part. Run control.

(Third invention) In the in-furnace inspection device, a propulsion device for swimming movement, a suction part for adsorbing the in-reactor inspection device main body to the inspection object, and a moving mechanism for moving the in-furnace inspection device body in contact with the inspection object. An inspection sensor for performing the VT work and the UT work, a scanning mechanism for operating and scanning the inspection sensor with respect to the in-core inspection apparatus body, and a laser light reflection plate for detecting the position of the in-core inspection apparatus. , A tracking light emitter and an inclination angle detector for detecting the inclination of the inspection apparatus body.

The propulsion device makes it possible to approach the object to be inspected while swimming, and further press the in-furnace inspection device body until it comes into contact with the portion to be inspected. Then, when fixing the apparatus main body, it is sucked and fixed by the suction unit, and the inspection sensor is scanned by the scanning mechanism. When the main body of the apparatus is not fixed, the moving mechanism moves along the welding line while scanning the inspection sensor while being in contact with the inspection object.

The laser light is reflected by the laser light reflection plate, the position of the in-furnace inspecting apparatus main body is measured by the position detecting device, and the position of the in-reactor inspecting apparatus main body is detected in accordance with the tilt angle from the tilt angle detecting section. Run control. Further, the in-core inspection device is tracked by the position detection device with the luminous body provided in the in-core inspection device as a mark.

(Fourth Invention) At least one chamber, which is operable in parallel with the propulsion axis of the propulsion unit, is arranged in the suction section to have a suction function for a site to be inspected. With the propulsion device approaching the inspection target portion and the moving mechanism of the in-furnace inspection device body in contact with the inspection target portion, the adsorption chamber is projected and brought into contact with the inspection target portion surface. Then, since the pressure inside the adsorption chamber becomes negative due to the action of the propulsion device to remove the fluid, the in-furnace inspection apparatus main body can be adsorbed and fixed to the inspection target portion.

(Fifth Invention) The propulsion unit is composed of a motor and a propeller, and is arranged vertically, horizontally, and vertically with respect to a vertical surface in the furnace.
It has translational freedom in the front-back direction and freedom of movement about the vertical axis and rotation about the normal axis. With these degrees of freedom of movement, it swims to each inspection object in the furnace and enters the narrow area.
Then, the part to be inspected is approached and contacted.

(Sixth Invention) The moving mechanism is composed of at least two driving wheels, and each wheel rotating shaft is rotatable so that the traveling direction can be changed between the vertical direction and the horizontal direction. After the in-furnace inspecting device is brought into contact with the inspection object, the direction of the wheel is changed and the device is moved vertically or horizontally.
Further, the wheel rotating shaft is controlled by the traveling control command from the in-furnace inspection device to adjust the traveling direction.

(Seventh Invention) In the in-furnace inspecting device, the angles of the moving mechanism, the propulsion unit and the suction unit can be adjusted with respect to the contact surface of the inspecting sensor.
Since the inner surface of the reactor pressure vessel and the inner wall of the shroud and the outer wall of the shroud are bent differently in the surface to be inspected, the angle is adjusted to follow the curvature. Also, when the plants have different curvature dimensions, the angle is adjusted to follow the curvature.

(Eighth Invention) In the in-furnace inspecting apparatus, a propulsion device for swimming movement, a moving mechanism for moving the in-reactor inspecting apparatus main body while in contact with an object to be inspected, and VT work and UT work are performed. It is composed of an inspection sensor and a scanning mechanism for operating and scanning the inspection sensor with respect to the in-furnace inspection apparatus main body. The propulsion device is used for swimming movement, and the in-furnace inspection device main body is pressed against the inspection object and moved by the movement mechanism to perform the inspection.

(Ninth invention) In the in-furnace inspection device, a propulsion device for swimming movement, a support wheel when the in-reactor inspection device main body is brought into contact with an object to be inspected, an inspection for performing VT work and UT work Sensor and a scanning mechanism for operating and scanning the inspection sensor with respect to the inspection apparatus main body. The propulsion device swims and moves, and the inspection device body is pressed against the inspection target. After that, the vehicle is moved by the propulsion device while applying the supporting wheels, and the inspection is performed.

[0051]

[0052]

( Tenth Invention) In the position detecting device of the in-core inspection system, a base installed on an upper end of a shroud upper body, a revolving table that revolves on the base about a center of rotation of the shroud, and an in-core inspection A laser beam projector / receiver for detecting the position of the device body, a tracking position detector for tracking the in-core inspection device body, a laser beam projector / receiver and a tracking position detector And a tracking mechanism installed on the turning table.

The turning table and the tracking mechanism are operated to measure the positions of the laser light projecting section and the tracking position detecting section toward the main body of the in-core inspection apparatus to measure the position of the main body of the in-core inspection apparatus. The position is detected and the position on the inspection target is grasped.

[0055]

[0056]

[0057]

( Eleventh Invention) In the position detecting device, a laser beam is projected from the light emitting element of the laser beam projecting / receiving section, and the reflected laser beam is received by the light receiving element. The received light detection circuit detects only the reflected light that exceeds an arbitrary received light level, measures the time from light projection to received light detection, converts it into a distance, and detects the distance between the position detection device and the in-core inspection device.

Further, in the tracking position detecting section, the reflected light of the laser beam projected by the issuing element of the laser beam projecting / receiving section is photographed by the television camera. Then, image processing of the video is performed, the deviation between the designated coordinates of the video, for example, the central coordinates and the coordinates to be received and displayed is obtained by the deviation detector, and the movement amount of the tracking mechanism is calculated and controlled so that the deviation amount is eliminated. The tracking is always performed so that the positional relationship between the in-core inspection device and the position detection device is kept constant.

[0060] In (twelfth invention) the position detecting device, and projecting the laser beam from the light emitting element of the laser light emitting and receiving unit, for receiving the laser light that is reflected by the light receiving element. The light receiving detection circuit detects only the reflected light that exceeds an arbitrary light receiving level, and the distance between the position detection device and the in-core inspection device is detected by measuring the time from light projection to light reception detection and converting it into a distance. .

Further, in the tracking position detecting section, the projection of the light emitting body provided in the in-furnace inspecting device is photographed by the television camera. Then, image processing of the video is performed, the shift detector obtains the shift between the designated coordinates of the video, for example, the center coordinate and the coordinate for receiving and displaying, and the movement amount of the tracking mechanism is calculated and controlled so that the shift amount is eliminated. The tracking is always performed so that the positional relationship between the in-core inspection device and the position detection device is kept constant.

[0062]

( Thirteenth Invention) In order to inspect the welding line between the inner wall of the reactor pressure vessel and the inner and outer walls of the shroud, the in-reactor inspection device is moved to the vicinity of the inspection object by swimming and brought into contact with the inspection object. After the contact, the inspection is carried out by the inspection sensor mounted on the in-core inspection device body while moving by the traveling driving force generated by the pressing force.
Further, the position of the in-furnace inspection device is detected and the traveling is controlled by the positioning device to fix the inspection site.

[0064]

[0065]

Embodiments of the in-core inspection system, the in-core inspection device, the position detecting device and the in-core inspection method according to the present invention will be sequentially described with reference to FIGS. 1 to 7. In the present embodiment, the in-furnace inspection system is roughly divided into an in-furnace inspecting device and a position detecting device. Therefore, first, an in-furnace inspecting system according to an embodiment will be described with reference to FIG.
5 to 5, the in-furnace inspecting apparatus will be described in detail, the position detecting apparatus will be described in detail with reference to FIGS. 6 and 7, and the in-reactor inspecting method will be incorporated at the same time in the description.

That is, in FIG. 1, reference numeral 1 indicates a reactor pressure vessel, and a shroud 2 is installed in the reactor pressure vessel 1. The shroud 2 includes a large diameter shroud upper body 2a, a medium diameter shroud middle portion body 2b, and a small diameter shroud lower body 2c. The shroud upper shell 2a has an upper plate incorporated therein, and the shroud lower shell 2c has a core support plate incorporated therein.
c is connected to the shroud support 3, and the shroud 2 is supported in the reactor pressure vessel 1 by the shroud support 3.

An annulus portion 4 is formed between the inner wall of the reactor pressure vessel 1 and the outer wall of the shroud 2, and a jet pump 5 is installed in the annulus portion 4. An operation floor 6 is laid above the reactor pressure vessel 1.

The inspection target portion in the reactor pressure vessel 1 is 1
In-furnace inspecting devices 7 are arranged, and FIG. 1 shows a state in which the in-furnace inspecting devices 7 are moved to and scattered at arbitrary inspection target parts.

Further, a base 8 is installed on the upper end of the shroud upper body 2a, and the position of the in-core inspection device 7 is detected on this base 8 to move the in-core inspection device 7 to a predetermined inspection target portion. A position detector 9 is provided.

The position detecting device 9 is provided with a base 8, a turning table 10 attached to the base 8, a tracking mechanism 11 attached to the lower surface of the turning table 10, and a lower part of the tracking mechanism 11. The laser light projecting / receiving unit 12 and the tracking position detecting unit 13 are provided.

The in-furnace inspection device 7 and the position detection device 9 are connected to a control panel 15 installed on the operation floor 6 by a cable 14, and the control panel 15 is connected to an operation panel 16. The control panel 15 is a control unit for controlling the in-furnace inspection device 7 and the position detection device 9, and the operation panel 16 is an operation unit for operating the in-furnace inspection device 7 and the position detection device 9. It should be noted that the control panel 16 may be integrated with the operation unit.

The in-reactor inspecting device 7 is arranged at an inspection target portion on the inner wall surface of the reactor pressure vessel 1 and the inner and outer surfaces of the shroud 2,
While moving, a visual inspection (VT) or ultrasonic flaw detection test (UT) around each horizontal and vertical welding line of each inspection target site is performed. The turning table 10 is arranged on the base 8 so as to be turnable with respect to the center of the shroud 2.

The tracking mechanism 11 is used when the in-reactor inspection device 7 is located on the inner wall of the reactor pressure vessel 1 and the outer wall of the shroud 2 in the annulus portion 4 and when it is located on the inner wall of the shroud 2. It is provided in the peripheral portion and the center of the base 8, respectively.

Laser light projector / receiver 12 and tracking position detector
Reference numeral 13 tracks the in-furnace inspection device 7 to detect the position. The operation and control of the in-furnace inspection device 7 and the position detection device 9 are performed on the operation floor 6 by the control panel 15 and the operation panel 16.

Next, referring to FIG. 2 to FIG.
An example will be described. The in-core inspection device 7 shown in FIG. 2 is a vertically long rectangular in-core inspection device main body (hereinafter referred to as the main body) 17
And a main body frame 18 integrally provided with the main body 17 on both sides of the main body 17. The main body 17 is provided with a UT probe 19 as an inspection sensor and a VT camera 20 in the vertical and horizontal directions. An up / down scanning mechanism 21 as a scanning mechanism of the inspection sensor and a left / right scanning mechanism 22 are provided so as to be movable, and a pair of light emitting elements 23 is attached to the upper end surface of the main body 17.

The vertical scanning mechanism 21 includes a screw rod 24 and this screw rod.
It has a guide member 21a which moves up and down along the screw of 24, and a motor 25 which drives this guide member 21a, and the UT attached to the guide member 21a by the rotation of the motor 25 incorporated in the vertical scanning mechanism 21. The probe 19 and the VT camera 20 move up and down. The left / right scanning mechanism 22 has a spur gear 26 on the lower surface of the guide member 21a, and when the spur gear 26 is rotated by a motor 25, the UT probe 19 and the VT camera 20 are rotated.

On the other hand, a propulsion device 27, a moving mechanism 28, a corner reflector 29 as a laser reflection plate for reflecting laser light, a float 30, and an emitting element 23 are attached to the main body frame 18. The light emitting element 23 and the corner reflector 29 is provided on a side surface of the upper surface and the body frame 18 in the furnace inspection apparatus main body 17 for position detection and tracking by the position detection device 9.

In particular, two sets are provided in the upper part so that the laser beam can be projected through the upper lattice plate and the core support plate and the light beam can be received from the issuing element 23 so that the light beam can be projected and received even if one of them is blocked. There is. A tilt angle detector (not shown) is provided to detect the tilt during travel control. A float 23 is provided in the upper part, and the center of buoyancy is always above the center of gravity, and the body moves while swimming while maintaining the posture shown in FIG.

As shown in FIG. 3 (a), the propulsion unit 27 is provided with a suction unit 31. Since the propulsion device 27 performs swimming movement, the motor 32 provided in the cylindrical member 34 and the motor 32
It consists of a propeller 33 that rotates by 32, and is up and down, left and right with respect to a vertical wall. There is a freedom to move back and forth, and a total of six are provided on the main body frame 18.

The motor 32 is attached via a support member 35 to a cylindrical member 34 as a main body member of the propulsion device 27 provided on the main body frame 18 in a protruding manner. A bearing is provided on the outer peripheral surface of the cylindrical member 34.
A slide cylinder 37 is provided via 36, and an adsorption chamber 38 is provided between the slide cylinder 37 and the cylindrical member 34 via an O-ring.

A blade 40 is attached to the tip of the suction chamber 38, and an inclined cam groove 41 is formed on the side surface as shown in FIG. 3B. This cam groove 41 has a protrusion
42 is inserted, and the protrusion 42 is provided on the inner surface of the tip end portion of the sliding cylinder 37.

A rotating pulley is provided on the outer surface of the sliding cylinder 37.
43 is attached, a timing belt 44 is stretched around the rotation pulley 43, and the timing belt 44 is a rotation motor.
Rotate by 45. The rotary motor 45 is provided with an encoder 46.

The structure of the suction unit 31 will be described in more detail with reference to FIGS. 3A and 3B. The suction unit 31 is provided with a suction chamber 38 that slides back and forth on the cylindrical member 34 of the propulsion unit 27. A blade 40 is provided at the tip of the chamber 38 to give a suction function to an inspection target site, and the suction chamber 38 is sealed by a cylindrical member 34 and an O-ring 39.

A cam groove 41 is formed in the suction chamber 38, the projection 42 of the slide cylinder 37 is inserted into the cam groove 41, and the slide cylinder 37 slides to move the suction chamber 38 back and forth. To do.

That is, when the rotation motor 45 is driven by the control of the encoder 46 and the sliding cylinder 37 slides through the timing belt 44, the projection 42 slides in the circumferential direction, and the cam groove 41 follows this. Adsorption chamber 38
Slides in the axial direction.

Next, the moving mechanism 28 will be described with reference to FIGS.
Will be described. The moving mechanism 28 moves to the object to be inspected after swimming and moves while contacting the object to be inspected. As shown in FIG. 2A, four moving mechanisms 28 are provided on the main body frame 18, and each wheel is swung to move up, down, left and right. Direction, and further adjusts the traveling direction. In this embodiment, the case of four wheels is shown.

FIGS. 4 (a) and 4 (b) are a front view and a side view showing the structure of the driven wheels, and FIGS. 4 (c) and 4 (d) are a front view and a side view showing the structure of the drive wheels. . 4 (a), (b)
, The wheel 47 is supported by a support shaft 48 and rotates, the support shaft 48 is connected to a bracket 49 via a suspension 50 such as a spring, and the bracket 49 is rotatably supported by a bearing 51 and turns with respect to the main body frame 18. It is possible.

The bracket 49 is driven by a drive pulley 52, a timing belt 53, and a turning motor 54, and an encoder
The turning angle and the turning speed are controlled by 55 and the like. Control is performed so that the direction of the wheel 47 is changed according to the traveling direction of the in-furnace inspection device 7.

In FIGS. 4 (c) and 4 (d), the wheel 47 is driven by the rotation motor 56 to rotate with respect to the support shaft 48 fixed to the bracket 49. The direction of the wheel 47 is controlled in the same manner as the driven wheel to control the turning angle and the turning speed, and the direction of the wheel 47 is changed according to the traveling direction of the in-core inspection device 7.

In this embodiment, four wheels are used, and if all are used as driving wheels, one wheel may float due to the unevenness of the surface to be inspected. Therefore, by using at least two diagonal wheels as driven wheels and the rest as driving wheels, or by using all as driving wheels and providing a suspension 50 on at least one wheel, it is possible to absorb surface irregularities and bring all wheels into contact. It is possible to move easily.

After the in-furnace inspecting device 7 is pressed against the inspected part by the propulsion device 27, the suction chamber 38 is slid and the blade 40 is moved as described above, as shown in FIG. 5 (a). When it is pressed against the inspection target site, the propeller 33 of the propulsion device 27 removes the fluid, so that the pressure in the adsorption chamber 38 becomes a negative pressure.
Can be adsorbed. As shown in FIG.
When the suction chamber 38 is returned, the in-core inspection device 7 is pressed against the inspection target site by the propulsive force of the propulsion device 27.

Next, a distance measuring method using laser light in the position detecting device 9 will be described with reference to FIG. FIG. 6 is a conceptual diagram showing the measurement principle. A light projecting lens 57 and a light receiving lens 58 which are the laser light projecting and receiving section 12 of the position detecting device 9.
Is a light emitting element 60 and a light receiving element 61 through an optical fiber 59
It is connected to the. The light emitting element 60 and the light receiving element 61 are connected to a time measuring device 62 to form a laser range finder 63. The time measuring device 62 measures the time from the projection of the laser light to the reception of the laser light and converts it into a distance.

Here, the laser light projected from the light emitting element 60 is transmitted by the optical fiber 59, and the laser light projection unit
Light is projected from the 12 projection lenses 57 to the corner reflector 29 of the in-core inspection device 7. The laser light reflected by the corner reflector 29 is captured by the light receiving lens 58, and the optical fiber
It is transmitted by 59 and reaches the light receiving element 61.

Here, the transmission distance of the optical fiber 59 is Lf,
Assuming that the distance to be detected is Lx, the height difference between the high-corner reflector and the low-corner reflector is Δl, and the respective transmission times are Tf, Tx, and Δt, the time from light projection to light reception is shown in FIG. As shown in (b), the corner reflector 29 having a high height has a value of 2 (Tf + Tx), and the corner reflector 29 having a low height has a value of 2 (Tf + Tx + Δt) 2. Here, Tf and Δt are known and given. Therefore, Lx can be converted from Tx and detected by the laser rangefinder 63. Where the corner reflector 29
The reason why the two types with different heights are provided is to enable the distance measurement even if one of them is blocked by an obstacle or the like.

Next, a method of tracking the in-core inspection device by the position detection device will be described with reference to FIG. FIG. 7 is a conceptual diagram showing a tracking method of the in-core inspection device 7. The in-core inspection device 7 is provided with the light emitting element 23, and the TV camera 65, which is the tracking position detection unit 13 of the position detection device, has a filter 64.
This light emitting element 23 is photographed via.

Then, the photographed image is input to the image processing device 67 through the image input device 66, and image processing is performed to obtain the deviation between the designated coordinates of the image, for example, the center coordinates and the coordinates to be received and displayed. The drive control device 68 controls the tracking mechanism 11 and the turning table 10 shown in FIG. 1 so that the amount of deviation is eliminated. As a result, it is possible to always keep the positional relationship between the in-core inspection device 7 and the position detection device 9 constant.

Next, an in-reactor inspection method for inspecting the weld line between the inner wall of the reactor pressure vessel 1 and the inner and outer walls of the shroud 2 by such an in-reactor inspection system will be described. That is, in FIG. 1, first, the in-reactor inspection device 7 is swim-moved in water in the reactor pressure vessel 1 to move to or near the inspection target portion and contact the inspection target portion. As described above, the in-furnace inspection device 7 always swims in an upright state as shown in FIG.

Since the in-reactor inspection device 7 can pass between the jet pump 5 and the inner wall of the reactor pressure vessel 1 and between the jet pump 5 and the outer wall of the shroud 2 in the annulus portion 4, it swims between the adjacent jet pumps 5. From there, each inspection target site is contacted, and in the shroud 2, it passes through the upper lattice plate and core support plate and is installed near each welding line.

When inspecting a horizontal welding line, the main body 17 is applied to the inspection target portion by the propulsive force of the propulsion device 27 of the in-core inspection device 7.
The UT probe 19 of the inspection sensor and the VT camera 20 perform the inspection while moving along the welding line with the moving mechanism 28 by the traveling driving force generated by the pressing force.

For the inspection of the vertical welding line, the suction unit 31 is pressed by the propulsion unit 14 and then the method described with reference to FIG.
In this way, the in-furnace inspection device 7 is adsorbed and fixed to the inspection target portion.
After fixing, the UT probe 19 and the VT camera 20 are installed along the welding line by the vertical scanning mechanism 21 and the horizontal scanning mechanism installed on the main body 17.
To scan for inspection.

At this time, in the inspection of the vertical welding line, the welding line may be located in the annulus portion in such a narrow area that the in-reactor inspection device 7 cannot pass through due to the jet pump riser brace or the jet pump riser blanket. Therefore, as shown in FIG. 2, the guide member of the vertical scanning mechanism 21 is made thinner than the width of the in-furnace inspection device body 17 so as to project vertically, and the UT probe 19 and the VT camera are provided at that portion.
Access 20 for inspection.

In addition to the above, the pressing means and the moving means of the in-furnace inspecting device 7 for pressing the in-furnace inspecting device 7 to the inspecting target by the propulsion device 27 and moving the in-furnace inspecting device 7 by the propulsion device 27 A method in which the in-furnace inspection device 7 is slid while being in contact with the inspection object by the part 31 and moved by the moving mechanism 28, and the in-furnace inspection device 7 is slid in contact with the inspection object by the adsorbing part 31 and the propulsion device 27 There is a way to move.

As shown in FIG. 1, the position detecting device 9 is installed on the shroud upper body 2a, and each of the in-core inspection devices 7 is installed.
On the inner wall of the reactor pressure vessel 1 and on the outer wall of the shroud 2 of the annulus portion 4, and the shroud 2
Swivel table 10 in case it is placed on the inner wall
A tracking mechanism 11 is arranged around and in the center, and the position of the in-core inspection device 7 is detected by the laser light projecting / receiving unit 12 and the tracking position detecting unit 13 at the tip.

In the annulus unit 4, the laser light projecting / receiving unit 12 and the tracking position detecting unit 13 are tracked so that the in-furnace inspection device 7 can be seen from directly above, and the laser light projecting / receiving unit 12 vertically moves a distance. And the turning angle of the turning table 10 are detected, the position of the in-core inspection device 7 on the inspection target portion, that is, the azimuth and height of the in-core inspection device can be grasped.

[0105] When the furnace inspection device 7 is disposed in the shroud 2 inside wall, place the mast to stretch to the center of the shroud 2, for tracking the position detecting section and the laser light emitting and receiving portion 12 at its distal end The position on the inner wall of the shroud 2 (direction and height of the in-core inspection device) is grasped from the distance measurement, the amount of expansion and contraction of the mast, and the rotation angle by providing 13 to track by the expansion and contraction of the mast and the rotation of the tip. It

As described in the above embodiments, according to the in-reactor inspection system, the inspecting apparatus, the position detecting apparatus, and the inspecting method, the VT inspection and UT of each welding line on the inner wall of the reactor pressure vessel and the inner and outer walls of the shroud are performed. It is necessary to reduce the amount of work and skill of workers who perform inspections by automatic remote control to improve work efficiency, reduce the exposure dose during work, and prepare each in-core inspection device for each inspection target. Instead, it is possible to use one in-furnace inspection device for general purpose, and it is possible to reduce the work time required for the arrangement of the inspection device and the inspection, and it is possible to shorten the periodic inspection process, for example.

Next, a second embodiment of the present invention will be described.
In the in-core inspection device 7 shown in FIG. 2, the angles of the moving mechanism 28, the propulsion unit 27, and the adsorption unit 31 can be adjusted with respect to the contact surfaces of the UT probe 19 and the VT camera 20 which are inspection sensors. As described above, the structure is such that it is connected to the body frame 18 by a hinge or the like.

With this, it is possible to adjust the difference in curvature between the inner wall of the reactor pressure vessel 1 and the inner and outer walls of the shroud 2, and it is also applicable when the nuclear reactor power plant and the shroud have different curvature dimensions. There is an effect. The other configurations and functions are the same as those of the first embodiment, and the description thereof will be omitted.

Next, a third embodiment of the present invention will be described with reference to FIG. In the position detecting device 9, when the in-core inspection device 7 is arranged on the inner wall of the shroud 2, the laser light projecting / receiving part 12 and the tracking position detecting part 13 are located at a position corresponding to the radius of the shroud 2 on the turning table 10. To install.

Since the main body 17 of the in-core inspection device 7 is constrained on the inner wall surface of the shroud 2, a laser for position detection is projected from above through the lattice of the upper lattice plate and the holes of the core support plate to track the same. The turning table 10 is turned and tracked by the working position detection unit 13.

With such a configuration, position detection and tracking can be performed even when fuel, reactor internals, etc. are present in the central portion of the shroud 2, and the tracking function is simplified, so that control is possible. Responsiveness can be improved and reliability can be increased. The other configurations and functions are the same as those in the first embodiment, and the description thereof will be omitted.

Next, a fourth embodiment of the present invention will be described.
In the position detecting device 9, when the in-core inspection device 7 is tracked by the tracking position detecting part 13, the reflected light of the laser light projected by the light projecting lens 57 of the laser light projecting / receiving part 12 is as shown in FIG. Take a picture with the TV camera 65.

Then, the image is input to the image input device 66, and the image processing device 67 performs image processing of the image to obtain the deviation between the designated coordinates of the image, for example, the center coordinates and the coordinates to be received and displayed, and eliminate the deviation amount. By calculating the movement amount of the tracking mechanism 11 and controlling the drive control device 68, the in-core inspection device 7
And the position detection device 9 are tracked so as to keep the positional relationship constant.

According to such a configuration, the in-core inspection device 7
Since the light emitting element 23 is not necessary,
Is simplified. The rest of the configuration and functions are similar to those of the first embodiment, so the description thereof will be omitted.

Next, a fifth embodiment of the present invention will be described. The propulsion unit 27 of the in-furnace inspection device 7 constituted by a water jet. By using a fluid having a large inertia as a driving source for movement, it is possible to improve the movement ability and increase the pressing force. Other configurations and functions are first
Since it is the same as the embodiment described above, the description thereof will be omitted.

[0116]

According to the first aspect of the present invention, the work amount and the skill level of a worker who automatically and remotely conducts VT inspection and UT inspection of each welding line on the inner wall of the reactor pressure vessel and the inner and outer walls of the shroud. It is possible to improve the work efficiency and reduce the exposure dose during work, and it is possible to use one inspection device for general purpose instead of preparing each inspection device for each inspection target. The work time required for installation and inspection can be reduced, and thus, for example, the periodic inspection process can be shortened.

According to the second invention, since the position detection and tracking can be performed only by projecting the laser light, the in-core inspection apparatus main body can be simplified. According to the third aspect of the present invention, the position detection by the laser beam and the tracking performed by capturing the light emitting body are separately performed, so that accuracy, responsiveness and reliability are improved.
According to the fourth aspect of the present invention, since the propulsion device has the adsorption function, the structure and structure of the in-core inspection device can be simplified and the weight can be reduced.

According to the fifth aspect of the present invention, the drive source supplied for movement is electric, and a hose or the like that greatly hinders the movement of the inspection apparatus body is not connected. It is easy to control and can be maneuverable. According to the sixth aspect of the invention, since the vehicle is moved by the wheels, reliable and smooth traveling movement is possible.

According to the seventh aspect of the present invention, since the inspection target surface is bent differently between the reactor pressure vessel inner wall and shroud inner wall and the shroud outer wall, it is possible to adjust the angle to follow the curvature. , It is possible to adjust the angle to follow the curvature even when the plants have different curvature dimensions, and also to adjust the angle to follow the curvature when the plants have different curvature dimensions. Since it is possible, the range of application will be dramatically expanded.

According to the eighth aspect of the present invention, the propulsion device can be moved by swimming, and the in-core inspection device main body can be pressed against the inspection object and moved by the movement mechanism to perform the inspection. It is possible to ensure reliable and smooth traveling movement by the corresponding traveling driving force.

According to the ninth aspect of the invention, the wheels are swimming-moved by the propulsion device, and further, the in-core inspection device main body is pressed against the object to be inspected. The degree of freedom in driving is reduced and the operation required for inspection can be achieved only by the propulsion device, so that the structure of the inspection device is simplified and the controllability is improved.

[0122]

According to the tenth aspect of the invention, the position of the moving in-furnace inspection device is directly detected from the outside with reference to the in-furnace internal structure, so that the accurate position can be detected.

[0124]

[0125]

According to the eleventh invention, since the position detection and tracking can be performed only by projecting the laser light, the in-core inspection apparatus main body is simplified, and according to the twelfth invention, the position detection and tracking by the laser light are separated. Accuracy, responsiveness and reliability are improved by dividing into

[0127]

According to the thirteenth invention, by performing scanning while moving, a wide area inspection can be performed in a short time, and the inspection time is shortened and the work efficiency is improved, so that the periodic inspection process can be shortened. become.

According to the nineteenth invention, the scanning mechanism of the in-core inspection device body scans the inspection sensor along the welding line to inspect, and the positioning device detects the position of the in-core inspection device body. By fixing the in-furnace inspection apparatus main body by performing the identification of the inspection portion, reliable and highly accurate scanning of the inspection sensor becomes possible.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of an in-reactor inspection system according to the present invention in a partial block and side view.

2A is a plan view showing an embodiment of the in-core inspection apparatus according to the present invention, and FIG. 2B is a side view of FIG.

3 (a) is a vertical cross-sectional view showing a partially enlarged side view of a propulsion unit and its surroundings in the in-core inspection device of FIG. 2;
(B) is a side view showing the adsorption chamber in (a).

4 (a) is an enlarged front view showing a driven wheel and its surroundings of a moving mechanism in the in-core inspection device of FIG. 2;
2A is a side view showing a partial cross section in FIG. 2A, and FIG.
The drive wheel of the moving mechanism in FIG., And the front view which expands and shows the periphery, (d) is a side view which shows with a partial cross section in (c).

5 (a) is a side view showing, in a partial cross section, a suction state in which the in-furnace inspection device in FIG. 2 is attached to an inspection target portion,
(B) is a side view which shows in a partial cross section the pressing state by a propulsion machine in (a).

6A is a conceptual diagram showing the measurement principle of distance measurement by a laser beam of the position detection device according to the in-core inspection system in FIG. 1, and FIG. 6B is a waveform diagram in FIG.

FIG. 7 is a conceptual diagram showing a tracking block of a position detection device according to the in-core inspection system in FIG.

FIG. 8 is a vertical cross-sectional view showing another embodiment of the in-core inspection system according to the present invention in a partial block and side view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Reactor pressure vessel, 2 ... Shroud, 2a ... Shroud upper shell, 2b ... Shroud middle shell, 2c ... Shroud lower shell, 3 ... Shroud support, 4 ... Annulus part, 5 ... Jet pump, 6 ... Operation floor,
7 ... furnace inspection device, 8 ... base, 9 ... position detection device, 10
... Swivel table, 11 ... Tracking mechanism, 12 ... Laser projecting / receiving section, 13 ... Tracking position detecting section, 14 ... Cable, 15 ... Control panel, 16 ... Operation panel, 17 ... Inspection apparatus main body, 18 ... Main frame , 19 ... UT probe, 20 ... VT camera, 21 ... Vertical scanning mechanism, 21a ... Guide member, 22 ... Horizontal scanning mechanism, 23 ... Light emitting element, 24 ... Screw rod, 25 ... Motor, 26 ... Spur gear, 27 … Propulsion device, 28… Moving mechanism, 29… Corner reflector, 30… Float, 31… Adsorption part, 32… Motor, 33… Propeller, 34… Cylindrical member, 35… Supporting member, 36… Bearing, 37… Sliding cylinder , 38 ... suction chamber, 39 ... O-ring, 40 ... blade, 41 ... cam groove, 42 ... protrusion, 43 ... rotation pulley, 44 ...
Timing belt, 45 ... Rotating motor, 46 ... Encoder, 47 ... Wheel, 48 ... Support shaft, 49 ... Bracket, 50
… Suspension, 51… Bearings, 52… Drive pulley,
53 ... Timing belt, 54 ... Rotating motor, 55 ... Encoder, 56 ... Rotating motor, 57 ... Emitter lens, 58 ... Light receiving lens, 59 ... Optical fiber, 60 ... Light emitting element, 61 ... Light receiving element,
62 ... Time measuring device, 63 ... Laser distance meter, 64 ... Filter, 65 ... Television camera, 66 ... Image input device, 67 ... Image processing device, 68 ... Drive control device.

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-2-154148 (JP, A) JP-A-2-216389 (JP, A) JP-A-62-245153 (JP, A) JP-A-60- 214253 (JP, A) JP 62-854 (JP, A) JP 6-138281 (JP, A) Actual development 55-157759 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G21C 17/003 G21C 17/08 G21C 19/02

Claims (13)

(57) [Claims] 1. An in-reactor inspection system for inspecting an inner wall of a reactor pressure vessel of a light water-cooled reactor and an inner and outer wall of a shroud having an upper shell, an intermediate shell and a lower shell, said inner wall of the reactor pressure vessel and outer wall of the shroud. and between the installed jet pump the reactor pressure vessel inner wall between the jet pump and the grating and the shroud of the upper grid plate provided to allow a top cylinder of the shroud passing between the shroud outer wall intermediate the holes in the core support plate provided on the barrel bottom is <br/> can pass, and furnace inspection apparatus for scanning a test sensor in contact with the inspected portion after moving to the examination target region, wherein Rotatable swivel located on top of shroud
A position detection device that detects traveling control the position of said furnace inspection apparatus provided in the table, and a control unit for controlling the position detecting device, that it has an operation section for operating the position detector Characteristic in-reactor inspection system. 2. The in- furnace inspection device propels the inside of the furnace.
And propellers fit, and suction portion for contacting a test object,
A moving mechanism for moving on the inspection target and the inspection target part
A test sensor for testing position, and characterized by including a scanning mechanism for scanning the test sensor, the laser beam reflector for detecting the position of the front Symbol furnace inspection apparatus main body tracking The in-reactor inspection system according to claim 1 . And wherein the furnace inspection device provided in the main body emitting light <br/> body, and characterized by including a tilt angle detector for detecting a tilt of the furnace main testing device The in-reactor inspection system according to claim 2. 4. The adsorption unit comprises an adsorption chamber movable in parallel with the motor shaft of the propulsion unit, and a blade attached to the tip of the chamber. In-furnace inspection system . Wherein said propulsion device is composed of a propeller which is mounted a motor and this motor, up and down relative to prior Symbol reactor pressure vessel in a vertical plane, the left and right around the normal axis around longitudinal translation and vertical axis The in-reactor inspection system according to claim 2, wherein the in-reactor inspection system is attached to a mechanism that imparts rotational freedom of rotation. Wherein said moving mechanism is constituted by at least two drive wheels, progress direction vertically and claims the wheel rotary shaft of each to be changed in the lateral direction is characterized by being freely configured swivel Item 2. The in-reactor inspection system according to Item 2. 7. The angle of the moving mechanism, the propulsion unit and the suction unit is adjustable with respect to the contact surface of the inspection sensor.
The in-core inspection system according to claim 2, characterized in that
Mu . 8. furnace inspection system according to claim 2, characterized by being provided with a scanning mechanism for scanning by operating the test sensor in the furnace inspection apparatus main body. 9. furnace inspection system according to claim 2, characterized by being provided with support wheels into the furnace main testing device
Mu . Wherein said position detecting device, furnace inspection system according to claim 1, comprising a laser light emitting and receiving portion and the tracking position detection unit. Wherein said position detecting device includes a laser light emitting and receiving portion having a receiving element for receiving the laser beam reflected from the light emitting element and the light-emitting element emits a laser beam, any of the laser beam Light receiving detection circuit for detecting only the reflected light exceeding the light receiving level, a distance meter for measuring the time from the projection of the laser light to the detection of the received light, and a distance meter for reflecting the laser light. And for detecting the reflected light from this laser light reflection plate, measuring the time from the projection of the laser light until it is reflected, and converting it into a distance to measure the position of the in- core inspection device body claims characterized in Rukoto that Yusuke a position detection unit, the
In-furnace inspection system described in 10 . 12. The tracking position detection unit includes a TV camera for projecting the projection light of the light emitting body provided in the furnace main testing device, an image input device for capturing an image captured by the television camera, the image Image processing device connected to input device
Furnace inspection of claim 10, wherein the Toka Ranaru
System . 13. A light water cooling type using an in-reactor inspection system.
A method for performing inspection of the reactor pressure vessel inner wall of the reactor and the shroud outer wall, a furnace inspection apparatus, the reactor pressure
Move the inside of the container to the vicinity of the inspection target
After moving, touch the inspection target part and attach the inspection sensor.
Scannable and rotatable on top of the shroud
Position of the in-core inspection device attached to the turning table
Furnace inspection method and performing inspection while detecting the position of said furnace inspection apparatus I by the position detection device that detects traveling control.