JPH10319170A - In-reactor inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attempt raising efficiency of inspection work in between upper grid side wall and shroud inner wall in a reactor pressure vessel. SOLUTION: A stay 50 freely movable in radial direction of a shroud is hung from a running body 30 running on a shroud upper flange 4. In the middle of the stay 50, a copying wheel 49 is provided via an air cylinder 48 in the middle of the stay 50. At the lower end, a holding arm 68 rotated up and down direction by a driving part 51 is supported via the rotary shaft 60. To the holding arm 68, an inspection means 70 is provided, which is moved along the holding arm 68 with a rotation axis for reciprocal motion penetrating inside the rotary shaft 60, a belt and a pulley.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactor inspection apparatus used in a reactor pressure vessel.

[0002]

2. Description of the Related Art FIG. 12 shows a cylindrical shroud 1 in a reactor pressure vessel, an upper lattice plate 6 installed substantially concentrically in the shroud 1, and a circuit around the inner wall of the shroud 1. FIG. 2 shows a partial cross section of a pipe-shaped core sparger 10 and an installation state of a bracket 11 holding the core sparger 10.

The shroud 1 has a multi-stage cylindrical shape, and is generally divided into three parts: a cylindrical upper body 2, an intermediate body 3, and a lower body (not shown).

[0004] A flange 5 is provided at the boundary between the cylinders as a connecting plate between the cylinders, and the portions in contact with each other are welded and integrated.

The upper lattice plate 6 has a cylindrical rim 7,
The rim 7, the upper grid plate flange 8, and the grid plate 9 are integrally formed by welding. The grid plate 9 is combined with the grid plate 9, and the upper grid plate flange 8 is provided on the upper and lower surfaces of the rim 7. I have. In particular, the present invention is suitable for an apparatus that inspects a welding line of an upper lattice plate in a reactor pressure vessel from an outer peripheral surface of the upper lattice plate.

It is necessary to inspect the circumferential welding line connecting the rim 7 and the upper grid plate flange 8 by applying ultrasonic inspection means to the rim 7 from the viewpoint of quality assurance. 6 is narrow, and a core sparger 10 and a bracket 11 for holding the core sparger are present above the gap. The existence of the core sparger obstructs the inspection means and the inspection means enters between the shroud 1 and the upper grid plate 6. It was difficult to make it.

FIG. 13 shows a conventional shroud upper flange 4.
1 shows an example of an in-furnace inspection device that travels.

A conventional reactor inspection apparatus is disclosed in Japanese Patent Application Laid-Open No. H08-11469.
As described in Japanese Patent Application Publication No. 4 (1994) -104, a traveling body 15 including a guide wheel 17 provided to be able to travel on a shroud upper flange 4 by a driving wheel 16 and to be able to move in a circumferential direction on the shroud upper flange, A stay 18 is attached to the body 30 and extends in the axial direction below the shroud 1.
A support device 19 is attached to the stay 18 at a right angle so as to be able to reciprocate, and an inspection device 20 is attached to a tip of the support device so as to be able to approach the shroud 1 to constitute an inspection apparatus.

The inspection means 20 is supported by the support means 19.
The outer wall surface of the upper body 2 is inspected by moving the traveling body 30 in the circumferential direction of the shroud 1 while pressing the.

With such an inspection apparatus, the stay 18 has a plurality of bendable mechanisms, so that it is possible to inspect the welding line of the intermediate cylinder 3 and the flange 5 in addition to the upper cylinder 2.

However, the inspection means is required to enter the narrow gap between the shroud 1 and the upper lattice plate 6 while avoiding interference with the core sparger 10 existing above the gap and the bracket 11 holding the core sparger. Is not disclosed.

[0012]

Conventionally, the traveling body 15 is installed on the upper shroud flange 4, and the inspection means 20 is inserted between the inner wall surface of the reactor pressure vessel and the outer wall surface of the shroud via the stay 18, Inspecting reactor pressure vessels and shroud welding lines.

When the upper lattice plate 6 in the shroud 1 is inspected by such an apparatus, the inner wall surface of the shroud 1 has an interference object such as the core sparger 10 and the upper lattice plate 6, and particularly the core splinter purger. 10 and upper lattice plate 6
Since the space between the upper lattice plate 6 and the upper surface is narrow, it is difficult to arrange the inspection means on the outer wall surface of the upper lattice plate 6.

Further, at least one or more power sources must pass between the core sparger 10 and the upper surface of the upper lattice plate 6, and stays and inspection means including the power source are provided between the core sparger 10 and the upper part. It is difficult to pass between the lattice plate 6 and the upper surface.

As described above, there has been a problem that the inspection apparatus which can be applied to the outside of the shroud 1 cannot be applied to the inspection inside the shroud 1 conventionally.

Therefore, a narrow place in the reactor pressure vessel,
In particular, interfering objects such as core spargers and brackets that support the core splinter sparger and allow it to easily and quickly pass between the core sparger and the top of the upper grid plate to allow inspection between the upper grid plate side wall and the shroud inner wall. It is desired to provide an inspection apparatus in a nuclear reactor capable of improving the efficiency of inspection work by easily avoiding the inspection means in a short time even when the inspection means is encountered.

Accordingly, an object of the present invention is to provide a reactor inspection apparatus capable of improving the efficiency of inspection work inside a shroud in a reactor pressure vessel.

[0018]

A first means for achieving the object of the present invention is a moving means movably mounted on a structure in a reactor pressure vessel, and an inspection means supported by the moving means. In the reactor inspection device provided with, a holding arm is vertically mounted on the moving means inside the shroud in the reactor pressure vessel and is movably mounted in the radial direction of the reactor pressure vessel, and the holding arm is provided with the holding arm. An inspection apparatus in a nuclear reactor characterized by being equipped with the inspection means,
The entire reactor inspection system can be moved by moving the moving means along the structure inside the reactor pressure vessel, the holding arm moves in the radial direction of the reactor pressure vessel, and the holding arm moves vertically at the destination. The inspection means rotated on the surface and supported by the holding arm is opposed to the inspection position. Can be reached without interference with the surrounding reactor internals.

The second means is an in-reactor inspection apparatus characterized in that the first means is provided with a means for pressing the inspection means against an object to be inspected. In addition, in the case of the ultrasonic flaw detection inspection means or the like which requires that the inspection means is pressed against the inspection object by the pressing means and the inspection means is in close contact with the inspection object and the inspection means is pressed against the inspection object. of,
A reliable inspection can be performed. Similarly, the third means is an in-reactor inspection apparatus according to the first means or the second means, wherein the inspection means is provided on the holding arm so as to be movable in the longitudinal direction of the holding arm. In addition to the effect of the means or the second means, the inspection means moves along the holding arm to change the inspection position of the inspection means, so that the scanning area and the degree of freedom of scanning of the inspection means are expanded.

Similarly, the fourth means comprises a traveling body movably mounted on an upper flange of a cylindrical shroud installed so as to surround the upper lattice plate in the reactor pressure vessel, and a moving means for moving the shroud from the traveling body. A device guide frame that is extended to the center of the cylindrical shape and is mounted on the traveling body, and is supported to be reciprocally movable from the device guide frame to the direction in which the guide frame extends so that the device is suspended downward from the inside of the shroud. A stay, a driving unit for reciprocatingly driving the stay from the traveling body along the device guide frame, a cylinder horizontally mounted with a piston rod facing a middle part of the stay in a vertical direction, and a protruding end of the piston rod. A scanning wheel rotatably mounted on the shaft, and a lower portion of the stay, which is horizontally oriented in a cylindrical radial direction of the shroud, and is rotatable. A rotary transmission shaft having a hollow structure, a rotary shaft for reciprocating motion rotatably inserted into the hollow of the rotary transmission shaft, and a rotary transmission shaft and a rotary shaft for reciprocating motion mounted below the stay. , A holding arm fixedly mounted at right angles to the rotation transmission shaft, and a belt wrapped around each rotating wheel rotatably mounted on the reciprocating rotation shaft and the rotating end of the holding arm. Inspection means mounted on the holding arm so as to be movable in the longitudinal direction of the holding arm and connected to the belt;
The traveling body travels along the upper part of the shroud to move the position of the entire reactor interior inspection apparatus, and the driving means moves the stay along the apparatus guide frame to the inside of the shroud. When moved to the wall, the holding arm in the horizontal position moves in the same direction as the stay moves, and is positioned above the gap between the shroud and the upper grid plate, avoiding the reactor internal structure above it. After that, the holding arm is rotated just below by rotating the rotation transmission shaft with the prime mover, and the detection means supported by the holding arm is positioned between the upper lattice plate and the inner wall surface of the shroud. When the piston rod protrudes toward the inner wall surface of the shroud and is stretched, the stay and the device below the stay are pushed toward the cylindrical center of the shroud by the reaction force. When the detecting means is pressed against the side surface of the upper lattice plate, and the prime mover rotates the reciprocating rotary shaft in the pressed state, the rotating wheel also rotates, the belt is driven in the vertical direction, and the inspection means connected to the belt is also used. The scanning position in the vertical direction can be changed by being driven simultaneously along the holding arm, and when the scanning position in the horizontal direction of the detecting means is changed, it is performed by moving the traveling body, and in a narrow place between the shroud and the upper lattice. An inspection is performed on the side of the upper lattice plate while changing the position of the detecting means that has entered.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

Conventionally, the shroud 1 is provided so as to concentrically surround the upper lattice plate 6 in the reactor pressure vessel.

An inspection apparatus in a nuclear reactor according to an embodiment of the present invention installed in the shroud 1 is as follows.

The in-reactor inspection apparatus has the following main components.

Shroud upper flange 4 of shroud 1
The traveling body 30 detachably mounted thereon, the device guide frame 37 installed on the traveling body 30 toward the center of the shroud 1, and the shroud 1
A stay 50 suspended in the axial direction of the shroud 1 and movable in the radial direction of the shroud 1, a drive unit 51 attached to the lower end of the stay 50, a rotation transmission shaft 60 rotatably mounted below the drive unit 51, and a rotation transmission shaft Drive unit 5
1, a reciprocating rotary shaft 61 rotatable with respect to both the rotation transmission shaft 60 and the rotation transmission shaft 60, a holding arm 68 provided at the tip of the rotation transmission shaft 60 and fixed, an inspection means 70 reciprocally attached to the holding arm 68, And so on.

A more specific explanation is as follows.

As shown in FIGS. 1 and 2, the main frame 31 detachably mounted on the upper shroud flange 4 includes:
As shown in FIG. 3, the drive wheels 32 are moved through the frame 39 so as to be able to move along the circumferential direction of the upper shroud flange.
Is attached. A handle 38 is provided at an upper portion of the main frame 31, and a motor 34 for driving the drive wheels 32 via a V-belt 35 is provided at a lower portion as a motor.

At least two or more guide wheels 33 are attached to the frame 39 so as to be pressed against both side surfaces of the upper shroud flange 4 in order to prevent the traveling body 30 from falling off.

An encoder 36 is mounted on one of the guide wheels 33.

An apparatus guide frame 37 is provided on the main frame 31 toward the center of the shroud 1. The apparatus guide frame 37 moves in the radial direction of the shroud 1 with respect to the traveling body 30 via guide wheels 52. A free stay 50 is attached.

A ball screw 53 is provided on the upper portion of the stay 50. A lead screw 40 is attached to the traveling body 30 toward the radial center of the shroud 1 on the main frame 31 so as to mesh with the ball nut 53, and the lead screw 40 rotates. As a result, the ball nut 53 moves, and the stay 50 integrated with the ball nut 53 can move in any direction of the above-described radius according to the rotation direction of the lead screw 40.

A stopper 42 is provided at the end of the shroud 1 in the radial center direction of the lead screw 40 to prevent the ball nut 53 and the stay 50 from falling off the lead screw 40.

An air cylinder 48 is attached to the middle part of the stay 50 in the vertical direction at a height in the radial direction of the shroud 1 and the piston rod is in a horizontal position facing the inner wall surface side of the shroud 1. Has a copying wheel 49 rotatably provided.

At the end of the piston rod of the air cylinder 48 on the side of the copying wheel 49, a proximity sensor 69 is disposed before and after in the traveling direction of the copying wheel 49, and the proximity sensor 69 is supported by the piston rod of the air cylinder 48. Before the copying wheel 49 hits an obstacle, the proximity sensor 69 hits the obstacle, causes a switching operation, notifies the existence of the obstacle, and urges the stopping operation of the traveling body 30. Alternatively, the switching operation may include a control circuit that stops the prime mover that controls the traveling of the traveling body 30, and the automatic stop may be performed.

A driving section 51 is attached to the lower end of the stay 50.

As shown in FIG. 4, a motor 54 and a motor 55 are provided inside the drive section 51 as a prime mover.

A worm screw a57 is attached to a rotary drive shaft of the motor 54, and the worm wheel a56 is engaged with the worm screw a57 at right angles as shown in FIG.

The worm wheel a56 is attached to one end of the rotation transmission shaft 60 having a hollow inside on the drive unit 51 side.

The rotation transmission shaft 60 is rotatably supported by the drive unit 51 by a bearing 62 provided on the drive unit 51.

The holding arm 68 is formed integrally with one end of the rotation transmitting shaft 60 on the side opposite to the driving portion 51 via a collar 63, and is provided rotatable about the rotation transmitting shaft 60 with respect to the driving portion 51. .

A worm screw b is provided on the shaft of the motor 55.
A worm wheel b58, which is fitted with and meshes with the worm wheel b59, is disposed at a right angle to the worm screw b59, penetrates through the inside of the rotation transmission shaft 60, and is provided rotatably with respect to the rotation transmission shaft 60. 61 is attached to one end of the drive unit 51 side.

The reciprocating rotary shaft 61 is rotatably supported by a drive unit and a rotation transmitting shaft 60 by a bearing 64 provided inside the holding arm 68.

A pulley 65 is fixedly attached to one end of the reciprocating rotary shaft 61 on the side opposite to the drive section 51, and one end (rotating end) of the holding arm 68 on the opposite side to the reciprocating rotary shaft 61. A pulley 66 is rotatably attached, and a wrap belt 67 is wrapped between the pulleys 65 and 66.

Accordingly, when the motor 54 is driven, the rotation transmitting shaft 60 is rotated, and the holding arm 68 can be rotated in the vertical direction about the rotation transmitting shaft 60. When the motor 55 is driven, the reciprocating rotary shaft 61 is rotated. And wrap around belt 6
7 Driven along the holding arm.

FIG. 7 shows the holding arm 68 and the inspection means 7 shown in FIG.
It is DD sectional drawing which showed the connection with 0.

The inspection means 70 is an ultrasonic flaw inspection means, and includes a probe shoe 71 using ultrasonic waves and a television camera 7.
2 and the inspection unit frame 73.

An inspection section frame 73 is attached to one end of a probe shoe 71 on which an ultrasonic probe 74 is molded, and a flat plate 76 is attached to a side surface of the probe shoe 71.
The television camera 72 is attached via the.

The middle part of the inspection unit frame 73 is held by the holding arm 68 so as to be slidable in the longitudinal direction of the holding arm 68 and not to fall off. The inspection frame 73 is fixed to the wrapping belt 67 by a pin 75. When the winding belt 67 is driven, the inspection means is also driven in the same direction as the driving direction of the winding belt 67.

Next, the mounting method and operation of the in-furnace inspection apparatus configured as described above will be described.

FIG. 8 shows a state immediately after the in-reactor inspection apparatus is installed on the upper flange of the shroud, FIG. 9 shows a state immediately after passing through the narrow portion between the core sparger and the upper lattice plate, and FIG. 2 shows a state in which the inspection means is directed to the outer wall surface of the upper lattice plate rim following the state of FIG.

When the in-furnace inspection apparatus is installed in the shroud 1, first, the apparatus is hung on a handle 38 by a not-shown rope or the like by a hoist or the like of a refueling truck (not shown), and the apparatus is hung in the furnace.

At this time, in order to prevent the inspection means 70 and the holding arm from interfering with the upper lattice plate, the holding arm 68 is rotated so that the longitudinal direction is horizontal as shown in FIG.

Shroud upper flange 4 of furnace inspection device
When the air cylinder 48 is suspended, the piston rod of the air cylinder 48 is contracted so as not to interfere with the upper shroud flange 4 and the core sparger 10.

Outer guide wheels on the outer surface of the shroud of the guide wheels 33 are largely separated from the outer surface of the upper shroud flange 4 to facilitate installation of the apparatus.
The device is placed on the shroud upper flange 4.

Monitoring when the traveling body 30 is placed on the upper shroud flange 4 is performed by an underwater TV camera or the like (not shown) prepared separately from the in-reactor inspection apparatus.

When the traveling body 30 rides on the shroud 1, the guide wheels 33 on the outer surface of the shroud among the guide wheels 33 provided at positions facing each other with the upper flange 4 of the shroud interposed therebetween are pressed by an air cylinder or the like (not shown). It is made to adhere to the outer surface of the upper shroud flange 4 by means.

As a result, the inspection apparatus in the nuclear reactor is pressed from the outer surface and the inner surface of the upper shroud flange 4, and the device does not fall off the shroud 1.

After being installed in the shroud 1, the in-reactor inspection apparatus operates as follows and approaches the inspection site.

First, the driving unit 51 and the holding arm 68 are moved in the circumferential direction of the shroud 1 by the traveling body 30 so that the holding arm 68 and the inspection means 70 do not interfere with the bracket 11. Circumferential position detection
In consideration of slippage of the drive wheel 32, the control is performed by an encoder 36 connected to a guide wheel 33 provided separately from the drive system.

When the target position is reached, the drive unit 51 and the holding arm 68 are moved toward the inner wall surface in the radial direction of the shroud 1 by the lead screw 40 as shown in FIG.
It is passed between the core sparger 10 and the upper surface of the upper lattice plate 6.

The radial position of the shroud 1 is detected by an encoder (not shown) connected to a motor for rotating the lead screw 40.

The inspection means 70 is the core sparger 1
After passing between 0 and the upper surface of the upper lattice plate 6, as shown in FIG. 10, the inspection arm 70 reaches the outer wall surface of the upper lattice plate rim 7, which is a region to be inspected, so that the holding arm 68 becomes vertical. Then, the rotation transmission shaft 60 is rotated by the motor 54 in the drive unit 51.

The rotation angle of the holding arm 68 is
This is performed by an encoder (not shown) connected to a motor 54 for rotating 0.

After the inspection means 70 approaches the inspection site,
The air cylinder 48 is pressed against the inner wall of the shroud, and the inspection means 70 is pressed by the pressing pressure. Drive unit 51
By rotating the motor 55 inside, the inspection means 70 is scanned in the vertical direction, and by the operation of the motor 34 and the drive wheels 32, the inspection means 70 is scanned in the circumferential direction of the upper lattice plate 6 to remove the outer wall of the upper lattice plate rim 7. Perform an inspection.

The scanning position of the inspection means 70 is
This is performed by an encoder (not shown) connected to a motor 55 that rotates a reciprocating rotary shaft 61 inside the unit.

The position at which the holding arm 68 interferes with the bracket 11 is determined as shown in FIG. 6 by a signal from a proximity sensor 69 provided at the end of the air cylinder 48 on the side of the copying wheel 49 to determine whether or not the bracket 11 has contacted. Or by sequence control based on the position data of the bracket 11 input in advance.

After the holding arm 68 reaches the bracket 11, the device is deformed to the state shown in FIG.
2 is rotated in the circumferential direction with respect to the shroud 1 and passes through the bracket 11.

After passing through in this manner, the state is returned to the state shown in FIG. 2 and the inspection is restarted.

In this procedure, one round of the shroud 1 is performed, and after the inspection is completed, the apparatus is removed in a procedure reverse to the installation.

Therefore, according to the present embodiment, an apparatus suitable for confirming the soundness of the welding line on the outer wall surface of the upper lattice plate 6 is obtained.

In this embodiment, an example is shown in which the television camera 72 and the ultrasonic probe 74 are mounted on the inspection means 70. However, other inspection means include an eddy current probe, a laser surveying instrument, an infrared camera, It does not hinder the use of such as.

Although the pulley 65, the pulley 66, the wrapping belt 67, and the air cylinder are used as the pressing means as the reciprocating means, it does not hinder the replacement with a lead screw or the like.

FIG. 11 shows an example in which the inspection means of the present invention is mounted on the opposite side. That is, the inspection means 70 shown in FIG. 1, FIG. 2, FIG.
And inspect the welded portion of the shroud 1 with the upper trunk 2 and the flange 5.

The inspection means is pressed by a lead screw.
The movement of the drive unit 51 toward the inner wall of the shroud 1 by the rotation of 40 is performed, or an air cylinder 77 separately attached to the holding arm 68 and a copying wheel 78 attached to the tip of the air cylinder 77.

Therefore, according to the present embodiment, an apparatus suitable for confirming the soundness of the welding line of the upper trunk 2 and the flange 5 of the shroud 1 is obtained.

In this embodiment, the running body 30 as the circumferential moving means is installed on the upper shroud flange 4 and runs. However, the running body 30 is mounted on the upper grid plate flange 8.
It may be installed on the upper surface and run.

As described above, according to the embodiment of the present invention, the inspection means can be inserted into the inspection part in a short time even in a very narrow place in the reactor pressure vessel, for example, between the core sparger and the upper surface of the upper lattice plate. Positioning becomes possible, and furthermore, it is possible to press the inspection means and scan reliably along the surface of the inspection site.

Further, even if the inspection means encounters an interfering object such as a bracket for supporting the core sparger, it is possible to easily avoid the interference in a short time. Efficiency can be improved.

[0079]

According to the first aspect of the present invention, even if the inspection means encounters the interference means with the inspection means due to the rotational movement on the vertical plane and the horizontal movement on the horizontal plane, the inspection means can be easily avoided in a short time. , The radiation dose received by the worker in the inspection work can be reduced, and the efficiency of the inspection work can be improved.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the inspection means is pressed against the object to be inspected so that the inspection can be surely performed and the inspection device in the reactor pressure vessel of the in-reactor inspection apparatus. Can be fixed.

According to the third aspect of the present invention, in addition to the effect of the first or second aspect, the inspection means is moved along the holding arm at the inspection position to enlarge the scanning area of the inspection means. Can be.

According to the fourth aspect of the present invention, even if the inspection means encounters an interfering object in the reactor pressure vessel, it can easily avoid it in a short time and inspect the narrow space between the shroud and the upper lattice plate. The inspection means can be reliably and easily guided to the inspection position by pushing the inspection means to the upper lattice plate, thereby reducing the radiation dose received by the worker in the inspection work and the efficiency of the inspection work. Improvement can be achieved.

[Brief description of the drawings]

FIG. 1 is a front view showing a state in which an inspection apparatus according to an embodiment of the present invention is installed on a shroud in a reactor pressure vessel and an inspection operation is performed.

FIG. 2 is a side view of FIG.

FIG. 3 is an enlarged view taken in the direction of arrows AA in FIG. 1;

FIG. 4 is a sectional view taken along the line BB of FIG. 1;

FIG. 5 is a sectional view taken along the line CC of FIG. 4;

FIG. 6 is a sectional view taken along the line DD in FIG. 1;

FIG. 7 is a sectional view taken along the line EE of FIG. 4;

FIG. 8 is a side view showing a state immediately after the in-reactor inspection apparatus according to the embodiment of the present invention is installed on a shroud in a reactor pressure vessel.

FIG. 9 is a side view showing a state immediately after the inspection means of the in-reactor inspection apparatus according to the embodiment of the present invention has passed through a narrow portion between the core sparger and the upper lattice plate upper surface.

FIG. 10 is a side view showing a state where the inspection means is directed to the outer wall surface of the upper lattice plate rim following the state of FIG. 9;

FIG. 11 is a side view showing an embodiment in which an inspection apparatus in a nuclear reactor according to another embodiment of the present invention is applied to inspection of a weld line of an upper shell of a shroud and a flange.

FIG. 12 is a perspective view showing how a shroud installed in a reactor pressure vessel and a reactor internal structure installed therein are engaged with each other.

FIG. 13 is a perspective view of a structure of a conventional in-reactor inspection apparatus for inspecting an outer surface of a shroud in a reactor pressure vessel using a traveling body installed on a shroud upper flange and a mast installed on the traveling body.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Shroud, 2 ... Upper trunk, 3 ... Middle trunk, 4 ... Shroud upper flange, 5 ... Flange, 6 ... Upper lattice plate, 7
... Rim, 8 ... Upper grid plate flange, 9 ... Grid plate, 10 ...
Core sparger, 11 bracket, 30 traveling body, 31 main frame, 32 driving wheel, 33 guide wheel, 34, 41, 54, 55 motor, 35 V-belt, 36 encoder, 37 device Guide frame, 3
8 Handle, 39, 76 Frame, 40 Lead Screw, 42 Stopper, 48, 77 Air Cylinder, 49, 78 Copy Wheel, 50 Stay, 51 Drive Unit, 52 Support Wheel, 53 Ball Nut, 56 ... Worm wheel a, 57 ... Worm screw a, 58 ...
Worm wheel b, 59 ... Worm screw b, 6
0: rotation transmission shaft, 61: rotation shaft for reciprocating motion, 62, 6
3, 64: bearing, 65, 66: pulley, 67: wrapping belt, 68: holding arm, 69: proximity sensor, 70
... inspection means, 71 ... probe shoe, 72 ... television camera, 73 ... inspection unit frame, 74 ... ultrasonic probe, 75
…pin.

Continued on the front page (72) Inventor Shigeru Kajiyama 7-2-1, Omika-cho, Hitachi City, Ibaraki Pref.

Claims (4)

[Claims] 1. An in-reactor inspection apparatus comprising: moving means movably mounted on a structure in a reactor pressure vessel; and inspection means supported by the moving means, wherein a shroud in the reactor pressure vessel is provided. An inspection apparatus in a nuclear reactor, characterized in that a holding arm is mounted on the moving means so as to be vertically movable and movable in a radial direction of the reactor pressure vessel inside the moving means, and the inspection means is provided on the holding arm. 2. An inspection apparatus according to claim 1, further comprising means for pressing said inspection means against an inspection object. 3. An inspection system in a nuclear reactor according to claim 1, wherein the inspection means is provided on the holding arm so as to be movable in a longitudinal direction of the holding arm. 4. A traveling body movably mounted on an upper flange of a cylindrical shroud installed to surround an upper lattice plate in a reactor pressure vessel, and a cylindrical center of the shroud from the traveling body. A device guide frame that is extended in the traveling direction and is mounted on the traveling body, and a stay that is supported from the device guide frame so as to be reciprocally movable in the direction in which the guide frame extends and that hangs downward from the inside of the shroud; A driving means for reciprocatingly driving the stay from the traveling body along the device guide frame, a cylinder mounted horizontally with a piston rod directed to an intermediate portion in the up-down direction of the stay, and a rotatable rotatable end of the piston rod. A scanning wheel mounted thereon, and a hollow structure rotatably mounted at a lower portion of the stay so as to be horizontally rotatable in a cylindrical radial direction of the shroud. A rotary transmission shaft, a reciprocating rotary shaft rotatably inserted into the hollow of the rotary transmission shaft, and a prime mover mounted below the stay for driving the rotary transmission shaft and the reciprocating rotary shaft to rotate. A holding arm fixedly mounted at right angles to the rotation transmitting shaft, a belt wrapped around each rotating wheel rotatably mounted on the reciprocating rotation shaft and a rotating end of the holding arm, and the holding arm. Inspection means mounted movably in the longitudinal direction of the holding arm and connected to the belt.