JP4300513B2 - Furnace bottom cleaning device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaning device that cleans the inner surface of the bottom of a reactor pressure vessel.
[0002]
[Prior art]
The bottom of the reactor pressure vessel is hemispherical on the outer surface side, and the inner surface side is a concave hemispherical surface having a small radius corresponding to the thickness of the vessel. It is inevitable that dust containing radioactive material accumulates on such a furnace bottom. In order to clean such dust, it is conceivable to extend the suction hose to the inner surface of the furnace bottom and suck the dust accumulated on the furnace bottom together with the reactor water.
[0003]
[Problems to be solved by the invention]
However, a large number of short cylindrical portions (CRD stubs) for passing through a control rod drive mechanism (hereinafter referred to as CRD) are projected at regular intervals on the bottom of the furnace. Therefore, it is extremely troublesome to suck and clean between the CRD stubs with a hose without much time and requires a lot of time and labor.
Then, this invention makes it a subject to provide the cleaning apparatus which can clean the furnace bottom part inner surface rapidly and reliably.
[0004]
[Means for Solving the Problems]
The present invention according to claim 1 has a traveling wheel (2) that rolls in contact with the inner surface of the furnace bottom (1) on the lower surface, and adjacent CRD stubs that protrude from the inner surface of the furnace bottom (1). An apparatus body (4) having a narrower width than between the minimum facing surfaces of 3),
A suction port (5) facing the furnace bottom (1) is provided on the lower surface of the front part, the rear part is pivotally supported by the apparatus body (4), and the drive means (6) supports the apparatus body (4). An oscillating suction body (7) that is oscillated and narrower than the minimum facing surface ;
A first camera (10) with a light for confirming the cleaning position is pivotally supported on the upper part of the apparatus main body (4) via the mounting member on the apparatus main body (4).
This is a furnace bottom cleaning device provided with a float (27) in which the first camera (10) floats upward and is positioned at a predetermined angle .
[0005]
The present invention according to claim 2 is the method according to claim 1,
A tip guide body (8) that is positioned in front of the oscillating suction body (7) and that is linearly guided between stub rows of adjacent CRD stubs (3) as the apparatus main body (4) moves. There is a furnace bottom cleaning device which is attached to the device body (4) via a connecting member (9).
[0007]
According to a third aspect of the present invention, in the first or second aspect ,
A furnace bottom cleaning device provided with a second camera (11) with a light for viewing the furnace bottom (1) on the swing suction body (7).
A fourth aspect of the present invention provides the method according to any one of the first to third aspects,
A positioning pipe (13) having a housing guide (12) which is removably fitted into the opening of the CRD stub (3) at the tip;
The positioning pipe (13) is provided with a hose guide (14),
The tip of the suction hose (15) guided up and down by the hose guide (14) is a furnace bottom cleaning device connected to the swing suction body (7).
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a furnace bottom cleaning device of the present invention, and is an explanatory view showing a state in which it is guided to the furnace bottom, FIG. 2 is a perspective view of a positioning pipe 13 for guiding the cleaning device, and FIG. FIG. 4 is an explanatory view showing a cleaning state of the cleaning device, FIG. 5 is a plan view thereof, FIG. 6 is a bottom view thereof, FIG. 7 is a left side view thereof, and FIG. FIG. 9 is an explanatory view showing a rotation range of the swing suction body 7, FIG. 9 is an explanatory view showing a cleaning state by the swing suction body 7 along with the progress of the apparatus main body 4, and FIG. 10 swings the swing suction body 7. FIG. 11 is an explanatory view showing an example of a procedure for cleaning the furnace bottom.
[0009]
As shown in FIG. 1, the cleaning device has a device main body 4, a swing suction body 7, a tip guide body 8, a guide rod 25, and a suction hose 15, and these are connected to a first operation pole 20. Guided to pipe 13.
As shown in FIGS. 4 and 6, the apparatus main body 4 has a pair of traveling wheels 2 spaced apart from each other as shown in FIGS. 4 and 6, and rolls in contact with the bottom 1 of the reactor pressure vessel. The inside of the apparatus main body 4 is formed hollow, and a pipe joint 30 projects from the rear end thereof, and the distal end portion of the suction hose 15 is fastened and fixed thereto via a fastening band (not shown).
[0010]
The rear end upper surface of the swing suction body 7 is connected to the lower surface of the front end portion of the apparatus main body 4 so that the rear end surface of the swing suction body 7 is rotatable and the interiors communicate with each other. The upper part of the swing suction body 7 is formed as shown in FIG. 10, and its opening is connected to the opening of the apparatus main body 4 and is rotatably attached. A driven gear 22 is fixed to the outer periphery of the rear end opening edge of the swing suction body 7 via a screw 29. The idle gear 24 meshes with the driven gear 22, and the drive gear 23 meshes with the idle gear 24. The drive gear 23 is fixed to the rotary shaft of the rotary actuator 6a. The rotary actuator 6a is driven to reciprocate in the circumferential direction. The rotary actuator 6a is fixed to the apparatus body 4 as shown in FIGS.
[0011]
Next, as shown in FIGS. 4 and 6, the swing suction body 7 is provided with a ball 26 rotatably projecting on the front and back of its lower surface, and on both sides adjacent to the front ball 26, the swing suction body 7. The suction port 5 opens on the lower surface of the. Then, the reactor water at the bottom of the furnace sucked from the suction port 5 passes through the inside of the oscillating suction body 7 and the inside of the apparatus body 4 and is discharged to the outside of the pressure vessel through the suction hose 15. As shown in FIG. 4, a second camera 11 with an illumination light is attached to the upper end of the oscillating suction member 7 downwardly via an attachment fitting 31.
Next, a first camera 10 with a light is pivotally supported on the upper surface of the apparatus body 4 via a connecting rod 33 in the longitudinal direction of the apparatus body 4. The first camera 10 is fixed downward on a mounting frame 34 attached to the upper end of the connecting rod 33. Further, a float 27 is fixed to the mounting frame 34.
[0012]
Next, a tip guide body 8 is pivotally supported on the top surface of the tip portion of the apparatus main body 4 via a connecting member 9 so that the tip side in FIG. Similarly, a guide rod 25 is pivotally supported by a fixed angle. The apparatus main body 4 and the swing suction body 7 are elongated as shown in FIG. 9, and the width of the apparatus main body 4 is formed slightly smaller than the interval between the minimum facing surfaces of a pair of adjacent CRD stubs 3. Further, the width of the swing suction body 7 is smaller than the width of the apparatus main body 4.
Further, as shown in FIG. 5, the width of the tip guide body 8 is substantially equal to the width of the apparatus body 4, and the diameter of the guide rod 25 is smaller than the width of the tip guide body 8.
[0013]
Next, the positioning pipe 13 for guiding the main part of the apparatus will be described. This is for guiding the swinging suction body 7 of the present apparatus to the furnace bottom and moving it along a certain direction on the furnace bottom. At the tip of the positioning pipe 13, a hanging guide 12 is projected and fixed downward via a mounting bracket 31. A cylindrical portion provided on one side of the mounting plate 35 is inserted in the intermediate portion of the positioning pipe 13, and is prevented from moving in the axial direction by the stop collar 18 of the positioning pipe 13. A pair of hose guides 14 are provided above and below the other side of the mounting plate 35, and a suction hose 15 is inserted into the hose guide 14 so as to be movable up and down as shown in FIG. In addition, the edge part of the inner surface of the hose guide 14 is formed in a circular arc shape in cross section to prevent damage to the outer surface of the hose.
A connecting portion 36 is provided at the upper end of the positioning pipe 13, and the lower end of the first operation pole 20 is connected to the connecting portion 36 in series as shown in FIG.
[0014]
A second operation pole 21 is attached to the upper portion of the suction hose 15 via an attachment band 37. The second operation pole 21 pushes the suction hose 15 downward, whereby the apparatus reaches the furnace surface along the positioning pipe 13, and then the suction hose 15 is further pushed forward, It moves in contact with the inner surface of the furnace bottom.
As shown in FIG. 2, a third camera 17 with a light is attached to the attachment plate 35 of the positioning pipe 13 via a bracket 16.
[0015]
【how to use】
Next, an example of a procedure for cleaning the furnace bottom with the cleaning device will be described. First, as shown in FIG. 1, with the suction hose 15 inserted through the hose guide 14 of the positioning pipe 13, the first operation pole 20 and the second operation pole 21 are made parallel to each other and pushed downward. Thereby, this apparatus is inserted into the inside of the reactor pressure vessel from above. At this time, the upper lid of the pressure vessel is opened, and the fuel rod, control rod, and control rod drive mechanism are removed.
In this state, the apparatus is lowered into the reactor water and inserted into one cell of the upper lattice plate 19 (FIG. 1) disposed in the middle of the pressure vessel. At this time, the first camera 10 is rotated upward by the float 27 and is positioned close to and parallel to the apparatus main body 4. For this reason, the entire apparatus easily passes through one opening of the upper lattice plate 19.
[0016]
Next, when the positioning pipe 13 reaches the furnace bottom, the handling guide 12 is fitted to the CRD stub 3 of the furnace bottom 1 as shown in FIG. At this time, the CRD stub 3 to be fitted is preferably located at the periphery of the furnace bottom 1 in FIG. For example, a, b · c to k · l. Inserting into one of these, the second operating pole 21 is then moved downward in FIG. Then, it is pushed by the suction hose 15 as shown in FIG. 4, and the traveling wheels 2 of the apparatus body 4 are guided to the furnace bottom 1 and move forward.
[0017]
As shown in FIG. 9, the apparatus body 4 enters between the pair of CRD stubs 3 and goes straight as indicated by the arrows in FIG. As shown in FIGS. 1 and 4, a tip guide body 8 and a guide rod 25 are arranged at the tip of the apparatus body 4 via a connecting member 9, and they are guided linearly between a number of CRD stubs 3. Because. At this time, the positions of the apparatus main body 4 and the swing suction body 7 are confirmed by the first camera 10 with a light. Then, the rotary actuator 6a of the driving means 6 is driven, and the swing suction body 7 moves to the left and right as shown in FIGS. At this time, in FIG. 9, since the CRD stub 3 is adjacent to a part of the rotation range of the swing suction body 7, the CRD stub 3 cannot be rotated any further by contact with the CRD stub 3. Move in the direction.
[0018]
The rotation range of the oscillating suction body 7 changes from a solid line state to a chain line state as the apparatus main body 4 advances. As a result, the furnace bottom is cleaned within the range indicated by the cleaning range 38. That is, a suction port 5 is formed in the lower surface of the front end of the swing suction body 7 as shown in FIG. It is guided outside. The cleaning state is displayed on the monitor television by a light-equipped second camera 11 (FIG. 4) provided at the tip of the swing suction body 7. Therefore, in FIG. 11, when cleaning is performed from a to an arrow as an example, the horizontal imaginary line is cleaned in the drawing, and then the next row is similarly cleaned from b. And the bottom of the furnace can be cleaned as much as possible by sequentially cleaning between adjacent rows.
[0019]
[Operation and effect of the invention]
The furnace bottom cleaning device of the present invention is formed so that the traveling wheel 2 provided on the lower surface of the narrow apparatus body 4 rolls in contact with the inner surface of the furnace bottom 1, so that it protrudes from the inner surface of the furnace bottom 1. It is possible to move between the CRD stubs 3. Then, the swing suction body 7 whose rear portion is pivotally supported by the device main body 4 is swung to the left and right via the driving means 6 so that both sides in the traveling direction of the device main body 4 are made as wide as possible. It moves and sucks the dust in the furnace bottom 1 together with the reactor water, so that the furnace bottom 1 can be cleaned in a wide range.
Furthermore, since the first camera 10 with the light for confirming the cleaning position is provided in the apparatus main body 4, the position of the apparatus main body 4 can be confirmed, and the furnace bottom 1 can be easily cleaned without any flaws . In addition, since the first camera 10 is pivotally attached to the apparatus main body 4, when the cleaning apparatus is guided downward from above the furnace, the inside of the upper lattice plate 19 positioned in the middle of the furnace can be easily obtained. Can pass through. And since the float 27 was provided in the 1st camera 10, it becomes easy to confirm the position of a cleaning apparatus by positioning it at a predetermined angle at the time of cleaning.
[0020]
In the above configuration, the distal end guide body 8 can be disposed in front of the swing suction body 7 via the connecting member 9. Thereby, the main body 4 is moved linearly between the stub column of CRD stub 3 can be a furnace bottom 1 so as not to leave the cleaning efficiently cleaned.
[0022]
In any of the above configurations, the second camera 11 with a light for viewing the furnace bottom 1 can be provided on the swing suction body 7. Thereby, the cleaning state of the furnace bottom 1 during cleaning and after cleaning can be confirmed.
In any one of the above-described configurations, the handling guide 12 is provided at the lower end of the positioning pipe 13, is detachably fitted into the opening of the CRD stub 3, and the suction hose 15 is moved up and down on the hose guide 14 of the positioning pipe 13. It can be guided freely and its tip can be connected to the swing suction body 7. Thereby, the specific range of the furnace bottom 1 can be reliably cleaned by this cleaning device.
[Brief description of the drawings]
FIG. 1 is a perspective view of a furnace bottom cleaning apparatus according to the present invention, illustrating a state in which the apparatus is guided to the furnace bottom.
FIG. 2 is a perspective view of a positioning pipe 13 for guiding the cleaning device.
FIG. 3 is an explanatory view showing a positioning state of the positioning pipe 13;
FIG. 4 is a front view showing a cleaning state in the furnace bottom 1 of the cleaning apparatus.
FIG. 5 is a plan view of the same.
FIG. 6 is a bottom view of the same.
FIG. 7 is a left side view of the same.
FIG. 8 is an explanatory view showing a rotation range of the swing suction body 7 of the cleaning device.
FIG. 9 is an explanatory view showing a cleaning range by the swing suction body 7 of the cleaning device.
FIG. 10 is an exploded explanatory view of the driving means 6 of the swing suction body 7 of the cleaning device.
FIG. 11 is an explanatory view showing an example of a cleaning order of the furnace bottom 1 by the cleaning device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Furnace bottom 2 Traveling wheel 3 CRD stub 4 Apparatus main body 5 Suction port 6 Driving means 6a Rotary actuator 7 Swing suction body 8 Tip guide body 9 Connecting material
10 First camera
11 Second camera
12 Handling guide
13 Positioning pipe
14 Hose guide
15 Suction hose
16 Bracket
17 Third camera
18 stop color
19 Upper lattice plate
20 First operation pole
21 Second operation pole
22 Driven gear
23 Drive gear
24 idle gear
25 guide bar
26 balls
27 Float
29 screw
30 fittings
31 Mounting bracket
32 cable
33 Connecting rod
34 Mounting frame
35 Mounting plate
36 Connection
37 Mounting band
38 Cleaning range

Claims (4)

The bottom of the furnace bottom (1) has a traveling wheel (2) that rolls in contact with the inner surface, and is wider than the minimum facing surface of the adjacent CRD stub (3) protruding from the inner surface of the furnace bottom (1). Narrow device body (4),
A suction port (5) facing the furnace bottom (1) is provided on the lower surface of the front part, the rear part is pivotally supported by the apparatus main body (4), and is driven by the drive means (6) with respect to the apparatus main body (4). An oscillating suction body (7) that is oscillated and narrower than between the minimum facing surfaces ;
A first camera (10) with a light for confirming the cleaning position is pivotally supported on the upper part of the apparatus main body (4) via an attachment member on the apparatus main body (4).
A furnace bottom cleaning device in which a float (27) is provided on the first camera (10) so that it floats upward and is positioned at a predetermined angle . In claim 1,
A tip guide body (8) positioned in front of the oscillating suction body (7) and linearly guided between stub rows of adjacent CRD stubs (3) as the apparatus main body (4) moves. However, the furnace bottom cleaning apparatus attached to the apparatus main body (4) through the connecting member (9). In claim 1 or claim 2 ,
A furnace bottom cleaning device provided with a second camera (11) with a light for viewing the furnace bottom (1) on the swing suction body (7). In any one of Claims 1-3 ,
A positioning pipe (13) having a housing guide (12) that is removably fitted into the opening of the CRD stub (3) at the tip;
The positioning pipe (13) is provided with a hose guide (14),
A furnace bottom cleaning device in which a tip of a suction hose (15) guided by the hose guide (14) to be movable up and down is connected to the swing suction body (7).

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