JPH01201198A - Flange sheet surface polisher - Google Patents

Abstract

PURPOSE:To improve working efficiency and to decrease exposure by constituting the polisher in such a manner that a magnet belt to be rotated by a motor mounted on a traveling carriage travels while said belt is attracted to bolts studded on the outside surface of a sheet surface and that the traveling carriage self-travels along the sheet surface. CONSTITUTION:The flange sheet surface polisher is so constituted that the magnet belt 23 is attracted to the stud bolts studded on the outside circumference of the sheet surface when the magnet belt 23 is rotated and that a polisher 33 travels and moves on the sheet surface when the magnet belt is successively rotationally moved. Namely, the polisher 33 is mounted on the traveling carriage 17. The polisher 33 progresses while the stud bolts are attracted by the magnet belt 23. The stud bolts constitute the orbit of the polisher 33. Cleaning and polishing of the main flange sheet surface of a reactor pressure vessel which are heretofore executed manually by an operator using grinding wheel are thus automatically executed with an electric motor as a driving source according to this device. The working efficiency is thereby improved and the operator's exposure is decreased.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a flange sorting surface polishing device for cleaning and removing dust such as O-ring roots attached to the main flange seat surface of a nuclear reactor pressure vessel. .

[Conventional technology]

As shown in Figure 6, the reactor pressure vessel consists of an upper lid 1 and a body 2.
are connected by a stud bolt 4 and a nut 5 via an O-ring (3 in FIG. 9), thereby sealing the entire pressure vessel.

7 and 8 are enlarged detailed views of section A in FIG. 6, showing details of the state of connection by the stud bolt 4. FIG. The stud bolt 4 is connected by the threaded portion 8 of the body flange 7 and the threaded portion 8 of the stand bolt 4 meshed together. Further, the stud bolt 4 passes through a through hole 10 formed in the upper lid flange 9, and a threaded portion 11 at the other end of the stud bolt 4 protrudes above the upper lid flange 9. A washer 6 and a nut 5 are attached to this threaded portion 11, and the upper lid 1 and the body 2 are tightly tightened by a stud bolt 4 via an O-ring (3 in FIG. 9).

FIG. 9 is a detailed enlarged view of section B in FIG. 8, showing the sealed state of the reactor pressure vessel by the O-ring 3 on the seat surface. The O-ring 3 is attached to the groove 13 formed on the seat surface 12 of the upper cover flange 9, and is pressed against the seat surface 12 of the fuselage flange 7. Thereafter, by tightening the fuselage flange 7 and the upper lid flange 9 with the stud bolts 4, the Olinog 3 is crushed into an elliptical shape.
Due to the reaction force, the seat surface 12. ．． 12 is sealed. Furthermore, the outer surface of the O-ring 3 is plated with silver, and this plating fills the gap between the QIJ song, the seat surface 12, and the surface of the groove 13 where the O-ring is attached, improving sealing performance.

By the way, the top cover 1 of the reactor pressure vessel is opened and closed once a year for regular inspection, and before the top cover 1 is closed, the
Ring 3 is replaced with a new one. At this time, 1. It is necessary to remove dust such as silver plating adhering to the seat surface 12 of the fuselage flange 7, and to clean and polish the seat surface 12. Furthermore, the O-ring mounting groove 13 of the upper lid flange 9 also needs to be cleaned and polished in the same manner.

■The 5y-tooth surface 12 of the integral flange 7 is used to inject water into the reactor pressure vessel 15 located in the reactor chamber 116 below the operation floor 14, as shown in FIGS. 10 and 11.
Polishing and cleaning work will be carried out in full condition. However, since the seat surface 12 is located inside the stud bolts 4 standing on the fuselage flange 7, polishing and cleaning of the seat surface 12 must be done manually between the stud bolts 4.4. Must be. Therefore, in order to minimize exposure to radiation from inside the reactor pressure vessel 15, workers lower their posture, put their hands through the gaps between the stud bolts 4.4, and directly use the grindstone to clean and polish. There is.

In addition, related to this type of device, for example, Japanese Utility Model Application Publication No. 134200/1983 and Japanese Utility Model Application No. 61/09778.
6% etc. are mentioned.

[Problems to be Solved by the Invention] The above-mentioned prior art forces the worker to take an unreasonable posture when cleaning and polishing the seat surface 12 of the fuselage flange 7 during the work or when checking after the work. Moreover, since it is a highly contaminated area, workers are wearing protective clothing and dust masks, and the work requires them to insert their hands through narrow gaps between the stud bolts 4.4, resulting in very poor work efficiency. Also,
There is also the problem of internal radiation exposure for workers due to the scattering of dust from cleaning.

On the other hand, in Japanese Utility Model Application Publication No. 60-134200, a scraper for removing the deposits is installed on a traveling cart that is movably placed on the flange surface, and the scraper is disposed near the scraper to remove the deposits that have been peeled off. a vacuum cleaner that suctions the flange, a rotating brush that is disposed after the scraper and polishes the flange surface, and a flange cleaning device that is disposed at the rear stage C1 of the rotary brush and has a extraction means that removes deposits from the flange. Equipment is shown.

However, in the above-mentioned device, sufficient consideration is not given to the condition that the stud bolts 4 are lined up on the outer circle of the flange seat surface 12 of the fuselage flange 2 of the reactor pressure vessel. Although it is possible to clean and polish the seat surface 12 after removing all of the star and nodopol I-4, the work of removing the star and nodopole I-4 and then re-embedding them will result in a new worker's radiation 'f11.
This is not economical and efficient because it results in high exposure and increases the overall working time.

On the other hand, although it is unknown in Japanese Utility Application No. 61-097786, a telescoping arm is attached to a frame attached to the upper part of the fuselage flange 2 of the reactor pressure vessel, a cleaning part is attached to one end of this telescoping arm, and the telescoping arm is attached to one end of the telescoping arm. The structure is such that the arm rotates around the center of the seat surface. The cleaning section includes a wire brush for cleaning the sheet surface, an electric motor for rotating the wire brush, a dust cover for preventing dust from scattering, a suction port, and the like. In this device, consideration has been given to the stud bolts that stand on the outer periphery of the seat surface, and the cleaning device can be set from inside the reactor pressure vessel via a mount. However, in order to set up the cleaning equipment, it is necessary to set up a large pedestal with the same dimensions as the reactor pressure vessel diameter during work, which not only causes additional radiation exposure for workers for setting up the pedestal, but also It is not economical or efficient because it takes a long time to work. Furthermore, it is necessary to secure a space to store the large mount after the work is completed.

An object of the present invention is to provide a flange sheet cleaning device that not only mechanizes and automates the work, but also improves the cleaning efficiency of the flange sheet surface where bolts of nuclear reactor pressure vessels and the like stand, and reduces the radiation exposure of workers. It's about doing.

[Means to solve the problem]

The above-mentioned purpose is to move a traveling trolley carrying a polishing tool and a vacuum unit along the fuselage seat surface to polish and clean the fuselage flange surface. This is achieved by installing a grindstone belt that runs while adhering to the bolt and a motor that drives the grindstone belt, and a traveling cart that runs along the bolt.

[Effect]

Rotated by a motor mounted on the traveling truck, the stone heald travels while adhering to the bolts Q standing on the outer surface of the seat surface, and thereby the traveling truck moves by itself along the seat surface.

Along with this self-propelled operation, the flange and surface are polished and cleaned by a roller grindstone mounted on a traveling cart, and the dust generated at this time is sucked by the YoF unit.
Never give up on the work environment.

Therefore, the stud bolt 4 remains embedded in the fuselage flange while the work is being carried out. There is no need to set up a new mount or the like in the 7972 part of the fuselage in order to run 4 l.

New additional work to configure the device is minimized.

〔Example〕

Embodiments of the present invention will be explained with reference to FIGS. 1 to 3.

Fig. 1 is a side view showing the whole of the present invention, Fig. 2 is a plan view of Fig. 1, and Fig. 3 is a view taken from arrow 1-1 in Fig. 2. It is a diagram.

This flange sheet 233 is the fuselage flange 7
A traveling trolley 1 that can run on the notebook surface 12 (47・g)
7, and a grinding unit 19 mounted on this running 11 Coffun 1 '7, which polishes the O-ring "i!" on the seat surface 12 and removes any dirt such as grudges that have adhered to it. A running function includes a vacuum unit 31 that sucks dust generated after polishing, a magnetic belt drive motor 22, and a magnetic heald 23 driven by this motor 22, and wheels 27 that facilitate smooth running of the traveling trolley 17. It is mainly composed of.

Next, details of each of these components will be explained. First, the grinding unit 19 will be explained with reference to FIGS. 1 and 2. The grinding unit 19 provides a roller grindstone 21 for grinding the sheet surface 12 of the body flange 7, a grindstone drive motor 20 for rotating the roller grindstone 21, and a sufficient pressing force to the roller grindstone 21, and also controls the position of the grinding unit 19. Grinding unit holder 26 fixed on the seat surface 12
It consists of The grinding unit) 19 is pivotally supported on the traveling carriage 17 by a bin 28, and is configured to be rotatable using the bin 28 as a support. The roller grindstone 21 is located on the sheet surface 12, and this roller grindstone 21 is connected to the grindstone drive motor 20.
The sheet surface 12 is polished by rotation. Roller whetstone 2
Sufficient pressing force during polishing in step 1 is applied by a grinding unit presser 26 supported by a bin 28 on a traveling carriage 17. Although not shown in the drawings, the grinding unit holding tool 26 has a built-in spring, which always presses the support member of the grinding unit 19 toward the seat surface 12 side of the body flange 7 with a constant force, thereby holding the roller grindstone 21 in the seat. Face 12
The structure is such that it is pressed against the Therefore, even if the loaf whetstone 21 is worn out by polishing, a certain pressing force can be maintained within a certain range.

Furthermore, when polishing and cleaning work is performed using a rotating brush such as the device disclosed in Japanese Utility Model Application Publication No. 60-134200, the rotating brush scratches the sheet surface 12, and these scratches cause the polishing performance to deteriorate. Although there is a risk of leakage to the outside of the reactor pressure vessel 15, when polishing with the roller grindstone 21 according to the present invention, damage to the notebook surface 12 can be prevented. By removing the tool 26 from the carriage 17, twisting it, and lifting the grinding unit F-19, it can be easily replaced with another roller grindstone 21. If the roller grindstone 21 is worn out, or if you want to change the roughness of the roller grindstone 21, the roller grindstone 21 can be replaced from the grinding unit 19.

Next, the vacuum unit 31 will be explained with reference to FIGS. 4 and 5. The vacuum unit]・to 31 and the traveling trolley 1'7 are constructed separately, and the traveling trolley 1'7 is constructed separately.
is provided with a suction port 30 located immediately on the blade side in the running direction of the roller grindstone 21, and the suction port 30 and the power 1-muyuyunoto 31
is connected to by a flexible hose 29. Dust generated during polishing with the roller grindstone 21 is removed from the suction port 30.
This prevents the reactor water from contaminating the reactor water by being sucked in quickly by the vacuum unit 31 via two flexible hoses, scattering onto the sheet surface 12, or falling into the inside of the reactor 1 [power vessel 15]. .

Next, the traveling function of the polishing device 33 will be explained using the first and second circles.

The polishing device 33 includes a pair of magnetic belt drive motors 22 attached to the front and rear ends of the traveling carriage 17, respectively.
When the magnetic belt 23 is rotated, the magnet heald 23 sequentially rotates while adhering to the stand bolts 4 standing on the outer periphery of the sealing surface 12. A polishing device 33 runs on top.

That is, the listening device 33 is mounted on the traveling cart 17, the polishing device 33 moves while adsorbing the stand bolts 4.4 with the grindstone belt 23, and the stand bolts 4, 4 form the orbit of the polishing device 33. .

Note that during the annual periodic inspection, a part of the stud bolt 4 is removed from the fuselage flange 7 in order to transport the fuel rods out of the reactor pressure vessel 15, but a dummy bolt is installed in the part where the stud bolt 4 is removed. (The dummy bolt is similar to the stud bolt 4.) L does not have to be very long, as long as it is long enough to attract the grindstone belt 23. ) is attached. Therefore, in the part where the stand bolt 4 has been removed, the running bogie 1'7 runs while the magnetic belt is attracted to the dummy bolt.

Here, the driving torque of the magnetic belt driving motor 22 is:
(Since the magnetic force of the n-stone belt 23 is set to exceed the attraction force between the stud bolt 4, the running function is not hindered.Furthermore, the outer surface of the magnetic belt 23 always has multiple Since the polishing device 33 runs while adsorbed to the stud bolt 4.4 of the polishing device 33, the risk of the polishing device 33 itself falling inside the seat surface 12 (inside the reactor pressure vessel 15) is prevented.

Further, since the positions of the stand bolts 4 are all set at constant intervals with respect to the O-ring contact surface to be polished on the seat surface 12, the stud bolts 4 also serve the function of positioning the traveling carriage 17.

Grinding wheel drive motor 20 and magnetic belt drive motor 2
The ON-OFF operation of Suinona No. 2 is carried out by remote control by a worker who is monitoring the stud bolt 4 from outside through the power cable 24.

In addition, in the embodiment of the present invention, the fuselage flange 7 and the flange 7 are
As described above, the seat surface 12 of the upper lid flange 9 is polished and cleaned using the polishing device 33, but due to the high radioactivity level near the fuselage flange 7, the upper lid flange 9, which is temporarily placed away from the reactor core by removing the top lid 1 during regular inspections. The radioactivity level in the vicinity is about 20:1, so in this embodiment, the polishing device 33 is limited to polishing and cleaning the fuselage flange 7, which has a high radioactivity level. Since the upper cover flange 9 has a low radioactivity level and there is little need for an automatic sheet surface polishing device, it is not necessarily necessary to apply the device of the present invention.

Further, the distance in the running direction of the magnetic belt may be any distance that allows it to simultaneously attract at least two or more bolts planted on the seat surface.

r effect] As described above, according to the present invention, the cleaning and polishing of the main flange seat surface of the reactor pressure vessel, which was conventionally done manually by workers using a grindstone, can be done automatically using an electric motor as the drive source. It can be done in a specific manner.

Thereby, it is possible to improve work efficiency and reduce radiation exposure of workers. Further, since the dust scattered during cleaning is collected by the vacuum unit, the spread of contamination of the work place and the contamination of the human body due to radioactivity can be kept to a minimum. Further, additional work in addition to conventional manual work can be kept to a necessary minimum. For example, there is no need to pull out or reset stand bolts, or to set up a large frame for device setup.

[Brief explanation of the drawing]

Fig. 1 is a side view showing one embodiment of the flange sheet surface polishing device of the present invention, Fig. 2 is a plan view of Fig. 1, Fig. 3 is a view taken along the arrow 1-1 in Fig. Fig. 1 is an explanatory diagram showing how the device is used, Fig. 5 is a sectional view showing the position where the seat surface polishing device is used during regular inspections, Fig. 6 is a sectional view of the reactor pressure vessel, Figs. Figure 8 is a detailed view of part A in Figure 6, and Figure 9
The figure shows the relationship between the flange seat surface and the O-ring.
10 is a sectional view of the reactor pressure vessel body during periodic inspection, and FIG. 11 is a partial perspective view showing details of D section in FIG. 10. ]...Top lid, 2...Body, 3...
・・OIJ song 4・・・・・・Stand bolt, 5・
...Nando, 6...Wano Soya, 7...
...Body flange, 12...Flange note surface, 13...O-ring mounting groove, 17...
・Travel 11 bogie, 19...Grinding unit, 20・
... Grinding wheel disturbance motor, 21 ... Roller grinding wheel, 22 ... Magnetic belt drive motor, 23
... Magnet belt, 24 ... Electric cable, 26 ... Grinding unit holder, 27 ...
...Wheel, 28...Pin, 29...
Flexible hose, 30...Suction port. Agent Masaru Yomoto, Patent Attorney - Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] (1) A traveling truck equipped with a polishing tool for polishing the surface of the fuselage flange and a vacuum unit for sucking dust is moved along the surface of the fuselage sheet to polish and clean the surface of the fuselage flange, in which the polisher is a roller. A flange sheet surface polishing device comprising a grindstone, the traveling carriage being equipped with a grindstone belt that runs while adhering to a bolt, and a motor for driving the grindstone belt, so that the traveling carriage runs along the bolt. .