JPS6025758B2 - Cleaning device for reactor control rod drive device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to maintenance and inspection work related to a multi-tube structure control rod drive device (hereinafter referred to as CRD) that drives control rods in a reactor pressure vessel, including replacement, disassembly, cleaning, assembly, This invention relates to inspection equipment, and in particular to CRD disassembly and cleaning equipment aimed at reducing the work period, workers, and radiation exposure by semi-automating the disassembly and cleaning work.

Conventional CRD maintenance and inspection work is roughly divided into {1'' CRD replacement work and '2} CRD disassembly, cleaning, and assembly work, and is performed manually. However, among the maintenance and inspection work for boiling water reactors, It had the disadvantages of having the worst working conditions, requiring a large number of workers, and requiring a large amount of radiation exposure.

However, the CRD replacement work has already been significantly improved by using a CRD remote replacement device, and it is now urgent to continue to improve the CRD disassembly, cleaning, and assembly work.

The present invention is a device for disassembling and cleaning a CRD, in which the radiation exposure of workers is relatively high among CRD disassembly, cleaning, and assembly operations. The purpose is to eliminate work that requires labor from the operator, except for removal work. The first feature of the present invention is that 'a) a water tank for cleaning the reactor control shank drive device, {b- a rail for moving the trolley installed in the water tank and on which the control shank drive device is mounted;' c) A trolley for mounting a control shaft drive device mounted on a rail, 'd)
A clamp unit for the control rod drive device provided on the truck; Clamp unit for assembly, {f bottle.

a cleaning water injection nozzle for cleaning the outer surface of the tube of the control rod drive device in a water tank; and (g) movable within the water tank and insertable into the tube of the control rod drive device;
The present invention includes a cleaning unit consisting of a lance equipped with a cleaning water spray nozzle for cleaning the inner surface of the tube in the water tank. A second feature is that the control shaft drive clamp unit [d} is provided with means for rotating the control shaft drive in the circumferential direction.

The third feature is that 'a) a water tank for cleaning the reactor control shank drive device, [b] a rail for moving the trolley installed in the tank and on which the control shank drive device is mounted, and 'c) a water tank for cleaning the reactor control shank drive device. A carriage for mounting a control beam drive device mounted on a rail, 'd} A clamp unit for the control beam drive device provided on the truck, {e- A clamp unit for the control beam drive device installed at a location different from the truck, A clamp unit for dismantling and assembling a movable control device that holds another part of the control device, a cleaning water injection nozzle for cleaning the outer surface of the tube of the 'f seat U control device in a water tank, and (g) the above-mentioned (h) a cleaning unit consisting of a lance that is movable within the water tank, insertable into the tube of the control shaft drive device, and equipped with a cleaning water spray nozzle for cleaning the inner surface of the tube in the water tank;
The clamp installed in the aquarium.

The fourth feature is that the filter includes a filter cleaning nozzle unit that sprays cleaning water in a circular direction or an acute angle direction onto the outside of the cylindrical filter taken out from the control shaft drive device by unit 'd} and (d). A filter cleaning nozzle unit (h) is provided independently in the water tank, surrounds or liquid-tightly seals the filter, and is attached to a filter cleaning cap that partially has a cleaning water outlet. It lies in the fact that it is a good thing.

The fifth feature is {a) a water tank for cleaning the Genko reactor control rod drive device, [b] a rail for moving the trolley laid in the water tank and carrying the control pole drive device, and tc) the rail. a carriage for mounting a control twill drive device mounted on the top; a clamp unit for the control twill drive device provided on the carriage;
'e - A clamp unit for disassembling and assembling the control beam drive device that is installed at a different location from the trolley, holds another part of the control beam drive device, and is movable; (g) a nozzle for cleaning the outer surface of the tube of the device; (g) movable within the water tank, insertable into the tube of the control shaft drive device, and equipped with a nozzle for spraying cleaning water onto the inner surface of the tube; (h) spraying cleaning water in the direction of the koji or in the acute angle direction onto a cylindrical filter installed in the water tank and taken out from the control drive device by the clamp units 'd} and 'te}; Filter cleaning nozzle unit (
The present invention is characterized in that it includes: i) a cover for surrounding the strainer provided in the control shaft drive device; and (j) a washing water injection unit for washing the strainer installed within the cover.

The structure of the device according to the present invention will be explained below with reference to the drawings.

A schematic structure of the device of the present invention is shown in FIG. 1, and a schematic diagram of the CRD is shown in FIG. 2. The water tank 1 is designed to allow the CRD to be washed underwater.

When cleaning the outer filter 31 and strainer 34, which are thought to have particularly high radiation levels, use adapter nozzle units 2 and 8 with a sealed structure to prevent the cleaning water from spreading to other locations as much as possible. ing. Filter cleaning nozzle unit 2, i.e.
The nozzle unit 2 for cleaning the outer filter and inner filter is attached to a ring cover 51 as shown in FIG.
, a nozzle 52, a self-sealing coupling 53 and a high pressure hose 54. This device is placed over the outer filter 31 and high pressure water is jetted from the nozzle 52 to roughly wash the inside of the outer filter 31 and the inside of the inner filter 55. Crud and wash water will be drained to the equipment drain system inside the reactor building. The cleaning water injection nozzle unit 8 for cleaning the rings baser and strainer consists of a half cover 61, a nozzle 62, a self-sealing coupling 63, and a high pressure hose 64, as shown in FIG. This device is placed over the strainer 34 and the CRD flange portion 35, the half-split cover 61 is fixed with a stopper, and high-pressure water is injected from the nozzle 62.
Perform a rough cleaning of the inside and the ○ ring baser 33. The crud and wash water will be drained into the equipment drain system inside the reactor building.
The water tank 1 is equipped with a level switch, overflow piping, and drain piping in addition to each unit.

A motor 3 with a variable speed gearbox is attached outside the water tank 1 and drives a cart 4. The trolley 4 runs on two rails installed inside the water tank 1. The rotation of the motor 3 is transmitted to the sprocket and chain and converted into linear motion. The object to be cleaned is a CRD clamp unit installed on a trolley, that is, a clamp unit 5 by moving brackets with rollers placed on the left and right sides by the back and forth movement of a cylinder.
Clamps various tubes with different outer diameters.

In addition, the back and forth movement of the cylinder is converted into circular movement by the rack and pinion, and the circular movement is converted into circular movement by the pinion and rack.
The structure is such that the bracket is gripped and released by converting it into a linear motion with two opposite movements. Further, by rotating the rollers provided on the clamp unit 5 on which the object to be cleaned is placed, the object to be cleaned is rotated. The rollers are rotated by an air motor, and a speed reduction mechanism is provided in the middle. When placing the object to be cleaned on a trolley, a cradle is used when necessary. The clamp unit 6 installed at a different location from the truck, that is, the right-hand end clamp unit 6 is connected to the lift drive unit 41 in FIG.
and a clamp drive section 43. Lift drive unit 4
1, after the rotational force of the air motor is decelerated by a gearbox, it is transmitted to three locations by a bevel gearbox 42,
Furthermore, the clamp drive unit 4 is connected via the lift rack and pinion.
Lift 3. An electromagnetic clutch 44 is installed in each clamp drive unit 43, and any clamp drive unit 4
3 lifts can be controlled individually. When the clamp drive unit 43 moves the clamp cylinder 45 up and down, the cam follower 47 attached to the clamp plate 46 moves in the diagonal groove, and the clamp plate 46 opens and closes parallel to the clamp guide bar to move the object to be cleaned. It has a structure that allows it to be clamped. When pulling out the object to be cleaned, pull out the
This can be done by moving the truck 4 after fixing it with a separately provided pull-out clamp unit 7. The clamping operation can be performed by converting the back and forth movement of the cylinder into circular movement using a rack and pinion, and moving the brackets placed on the left and right with respect to the object to be cleaned. The nozzle for cleaning the tube consists of a cleaning water injection nozzle 9a for cleaning the inner surface of the CRD tube and a cleaning water injection nozzle 10 for cleaning the outer surface, and cleaning may be performed simultaneously.

The inner surface cleaning nozzle 9a is attached to the tip of the lance 9b, and the entire length of the inner wall of the tube is cleaned by running the cart 4 carrying the tube while spraying high pressure water from the nozzle 9a onto the inner wall surface of the tube. During other work, the nozzle 9a is moved to a position where it does not interfere with the cart 4 using a air cylinder. The outer surface cleaning nozzle 10 is fixed at the center of the water tank, and when a CRD component passes directly under the nozzle 10, high-pressure water is sprayed from the nozzle to clean the outer surface. Incidentally, in the cleaning operation, one side is cleaned by the forward movement of the cart 4, then the part is rotated half a turn, and the remaining half side is cleaned by the backward movement of the cart 4. (The entire outer periphery is cleaned in one round trip.) The piping unit mainly consists of a high-pressure cleaning line, a low-pressure water line, and an air line.

The high pressure washing line consists of a high pressure hose, swivel joint,
Consists of valves and high pressure piping. The low pressure water line includes an overflow pipe, a drain pipe, and a drain pump. The air line is used to operate each cylinder, a motor, etc. The air line of the cleaning tank connected to the trolley 4 uses a Shinflex hose, and the cable carrier 11 is used together with the electrical cable to enable the trolley 4 to be moved.

In the present invention, the small parts cleaning tank unit 12 may be installed separately. This unit 12 consists of a cleaning tank and an ultrasonic oscillator. 4. Put the parts inside the CRD into the cleaning tank of this device, and then start the ultrasonic oscillator while letting the cleaning liquid flow into the cleaning tank. The drying tank unit 13, which cleans every detail of the parts by the generated ultrasonic waves, consists of a drying tank and a hot air generator opening/closing unit. Open the lid using an air cylinder, place the CRD disassembled parts on the drying tank floor, close the lid, and dry the parts by blowing hot air from the hot air generator at the end of the drying tank.

The air inside the pot is discharged into the duct inside the furnace building. High pressure pump 1
Reference numeral 4 is a horizontal, three-lotus plunger pump type, which repeats the suction and discharge strokes by the movement of the plunger to pressurize the discharged water.

Pressure adjustment equipment consists of an accumulator, safety valve, bypass valve, pressure gauge, etc. Accessories for high-pressure pumps include suction strainer, water tank, and high-pressure washing outlet valve (3
It consists of a one-way switching valve) and an ultra-high pressure hose. The electrical component unit 15 consists of an operation panel, a device main body control panel, a terminal box, and a high-pressure pump control panel.

Next, an example of the operation and working time of the apparatus of the present invention is shown in the following table.

Further, the operation steps of the apparatus will be explained with reference to FIGS. 6 to 17. Table * After removal, it is disassembled into each part, and after cleaning, the CRD body is transported to the drying tank unit 13 by crane operation onto the trolley unit 4, and then the clamp unit is moved to the drying tank unit 13. 5, the CRD is clamped onto the trolley unit 5 (FIG. 6).

In the clamped CRD, parts of the outer filter 31, inner filter 55, strainer 34, and O-ring baser 33, which have a high radiation dose, are cleaned with high-pressure water using the nozzle units 2 and 8 of a sealed structure (
Figure 7). Cleaned small parts outer filter 31,
Uncoupling spring rod 56, coupling stopper 3
2 and the inner filter 55 are removed from the CRD body using removal tongs or the like, and transported to the small parts cleaning tank unit 12. After removing the ring flange 36, press the push tongs 1
Parts of the piston tube 37 and index tube 38 are pulled out using 6 (FIG. 8). The truck 4 is moved to the right, and the pulled-out portion of the piston tube 37 is clamped by the pulled-out clamp unit 7. Next, by moving the cart 4 to the left, the piston tube 37 and the index tube 38 are extracted, and at the same time, the extracted index tube 38 (including the piston tube 37 inside) is sequentially clamped by the right-moving clamp unit 6'. Go (Figure 9). When the piston tube 37 and index tube 38 are removed, the guide cap 3 is removed.
9. Remove the collet assembly 40, and take out the strainer 34, O-ring baser 33, and ball retainer 41 with the clamp unit 5 unclamped. The removed small parts are transported to the small parts washing tank unit 12 (FIG. 10). With the CRD main body clamped, move the trolley 4 to the right, clean one side of the CRD main body with the outer surface cleaning nozzle 10 and the inner surface cleaning nozzle 9a, then rotate the CRD main body 180 degrees and move the trolley 4 to the left. The entire surface of the CRD body is cleaned by
(Fig. and Fig. 12). The clamp unit 5 is placed in an unclamped state on the cart 4 moving to the left, and the CRD body is transported to the drying tank unit 13 (FIG. 13). Next, the cart 4 is moved to the right, and the index tube 38 (inside the piston tube 37
(including the piston tube 37 inside) is transferred onto the carriage 4, and the index tube 38 (including the piston tube 37 inside) is clamped by the clamp unit 5 (FIG. 14). Next, the piston tube 37 is pulled out from the index tube 38 in the same manner as the piston tube 37 and index tube 38 were pulled out from the CRD body with the drive piston 43 loosened (FIG. 15). CR
D In the same way as cleaning the main body, clean the index tube 38.
After cleaning, it is transported to the drying tank unit 13. The piston tube 37, which is clamped by the right-hand clamp unit 6, is moved onto the carriage 4, and after being clamped by the clamp unit 5, the stop piston 44 is removed (FIG. 16). Remove the drive piston 42 with the clamp unit 5 unclamped (No. 17)
figure). The piston tube 37 is cleaned in the same manner as the CRD body and the index tube 38, and after cleaning, it is transported to the drying tank unit 13. CRD disassembly and cleaning using the above operating steps can be carried out by a total of two people, an operator of the device and a work assistant.

In addition, because small parts are dismantled manually, and large parts are dismantled and cleaned remotely and automatically, no worker effort is required. Based on the first feature of the present invention, the CRD can be installed underwater using the water tank {a}, the rail 'b} installed in the water tank, the loading trolley 'c}, and the clamp unit [d} installed on the trolley. , and can be moved within the aquarium.

Further, the outer surface of each tube constituting the CRD can be cleaned by the cleaning water jet nozzle [f} that cleans the outer surface of the tube. Furthermore, a cleaning unit (
According to g), a spray nozzle can be inserted into each tube constituting the CRD, and the entire inner surface of each tube can be cleaned by spraying cleaning water from the nozzle. In addition, since the CRD disassembly and assembly clamp unit {e) disassembles, assembles, or cleans each tube that makes up the CRD, it is possible to disassemble, clean, and assemble the CRD by underwater remote control. This makes it possible to minimize the radiation exposure of workers due to the CRD-attached crud, in combination with the water shielding effect in the aquarium. Furthermore, there is no need to worry about radioactive contamination of the surrounding area due to splashing of washing water. or,
Based on the second feature, it is equipped with a clamp unit {d' that can rotate the CRD in the circumferential direction, and when cleaning the CRD, the CRD mounted on the loading cart [c] is moved back and forth in the water tank {a). By rotating the clamp unit [d}, the entire inner and outer surfaces of each tube constituting the CRD can be cleaned.

Further, in the work of removing set screws from various small parts such as the filter ring baser of the CRD, the screws can be moved upward by rotating the CRD, which has the advantage of making the above work easier. Based on the third feature, the filter cleaning nozzle unit (h)
In D, cleaning water can be directly injected to the inner filter portion and outer filter portion, where the amount of adhered crud is the largest and the radiation dose is high, making it possible to perform extremely effective cleaning.

Furthermore, based on the fourth feature, when cleaning the inner filter portion and outer filter portion with high radiation dose, the filter cleaning cap provided on the filter cleaning nozzle unit (h) removes the cladding peeled off by cleaning from the water tank. Diffusion throughout the interior of the room can be prevented. or,
Based on the fifth feature, the strainer cleaning water injection nozzle unit (i) can clean the highly contaminated strainer section.

Moreover, since the cover (i) is provided, as in the case of the fourth feature, it is possible to prevent the cladding peeled off by cleaning from spreading throughout the interior of the water tank 'a'. The present invention is as described above, and by employing the present invention, the following effects can be obtained compared to the current working method.

Working time...2'3 Number of workers: 1/2 Radiation dose...1/2

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a control pole drive mechanism disassembly and cleaning device according to an embodiment of the present invention, Fig. 2 is a schematic diagram of a control pole drive mechanism, and Fig. 3 is a schematic diagram of a filter rough cleaning adapter nozzle unit. 4 is a detailed sectional view of the O-ring baser and adapter nozzle unit for rough cleaning of the strainer, FIG. 5 is a detailed view of the right row end clamp unit, and FIGS. 6 to 17 are details of this embodiment It is an explanatory diagram of the operation of the control salary drive mechanism disassembly and cleaning apparatus. DESCRIPTION OF SYMBOLS 1...Water tank, 2...Nozzle unit for filter cleaning, 3...Motor, 4...Dolly, 5...Clamp unit, 6... ... Clamp unit set up in a different place from the trolley, 7...
Pull-out clamp unit, 8...Cleaning water injection nozzle unit for strainer cleaning, 9a...Nozzle for cleaning the inner surface of the tube, 10...Nozzle for cleaning the outer surface of the tube, 11...Cable bearer , 12...Small parts cleaning tank unit, 13...Drying tank unit, 14...High pressure pump, 15...Electrical component unit, 16...Pushing Tongs. 3rd Diagram Kōzu N Ship's Disciple's Diagram Disciple's Diagram Heart Vertical Butterfly Diagram Station Diagram Ship's Diagram ○ Ship's Crucian Diagram

Claims (1)

[Scope of Claims] 1 (a) A water tank for cleaning the reactor control rod drive device, (b) A rail for moving a trolley laid in the water tank and on which the control rod drive device is mounted, (c) (d) a control rod drive device mounting truck mounted on the rail; (d) a control rod drive device clamp unit provided on the truck; (e) a control rod drive device mounting truck installed at a different location from the truck; A clamp unit for dismantling and reassembling the control rod drive unit that holds another part of the drive unit and is movable; (f) a cleaning water injection nozzle for cleaning the outer surface of the tube of the control rod drive unit in a water tank; and (g) ) A cleaning unit comprising a lance movable within the water tank, insertable into the tube of the control rod drive device, and equipped with a cleaning water spray nozzle for cleaning the inner surface of the tube in the water tank. A cleaning device for the reactor control rod drive system. 2. Cleaning of a nuclear reactor control rod drive device according to claim 1, characterized in that the control rod drive device clamp unit (d) is provided with means for rotating the control rod drive device in the circumferential direction. Device. 3 (a) A water tank for cleaning the reactor control rod drive device, (b) A rail for moving the trolley laid in the water tank and carrying the control rod drive device, (c) Placed on the rail. (d) a clamp unit for the control rod drive device provided on the truck; (e) a separate part of the control rod drive device installed at a different location from the truck; (f) a cleaning water injection nozzle for cleaning the outer surface of the tube of the control rod drive device in a water tank; and (g) a movable clamp unit for dismantling and reassembling the control rod drive device; (h) a lance installed in the water tank and capable of being inserted into the tube of the control rod drive and having a cleaning water spray nozzle for cleaning the inner surface of the tube in the water tank; For the cylindrical filter taken out from the control rod drive device by clamp units (d) and (e),
A cleaning device for a nuclear reactor control rod drive device, comprising a filter cleaning nozzle unit that sprays cleaning water in an axial direction or an acute angle direction. 4. The filter cleaning nozzle unit (h) is provided independently in the water tank, surrounds or liquid-tightly seals the filter, and is attached to a filter cleaning cap that partially has a cleaning water outlet. A cleaning device for a nuclear reactor control rod drive device according to claim 3, characterized in that the cleaning device is a cleaning device for a nuclear reactor control rod drive device according to claim 3. 5 (a) a water tank for cleaning the reactor control rod drive device, (b) a rail laid in the water tank for moving the trolley on which the control rod drive device is mounted, and (c) a water tank installed on the rail. (d) a clamp unit for the control rod drive device provided on the truck; (e) a control rod drive device mounting truck installed at a location different from the truck; A clamp unit for dismantling and assembling the control rod drive device that can be held and moved, (f) a cleaning water injection nozzle for cleaning the outer surface of the tube of the control rod drive device, (g)
(h) a cleaning unit comprising a lance that is movable within the water tank, insertable into the tube of the control rod drive device, and equipped with a nozzle for spraying cleaning water onto the inner surface of the tube; (h) the clamp unit installed in the water tank; (d
) and (e) a filter cleaning nozzle unit that sprays cleaning water in an axial direction or an acute angle direction onto the cylindrical filter taken out from the control rod drive; (i) a strainer provided in the control rod drive; 1. A cleaning device for a nuclear reactor control rod drive device, comprising: a cover for enclosing a strainer; and (j) a cleaning water injection unit for cleaning a strainer installed in the cover.