JPS6093996A - Inspection device for external appearance of fuel aggregate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for visually inspecting a fuel assembly of a nuclear reactor.

In general, fuel assemblies d are taken out from the reactor during periodic inspections of nuclear power generation equipment, and are transferred to a spent fuel bit in a refueling handling building located adjacent to the reactor containment vessel. The spent fuel is stored in a built-in spent fuel rack and taken out to an inspection bit in the same building to be inspected for defects in fuel consumption. This inspection includes a shipping inspection and a visual inspection of the outer periphery of the fuel assembly using a television camera. Shipping inspection is a method in which the fuel assembly is placed in a sealed container, circulation/arm pipes are connected to the bottom and top of the container, water is circulated in the container using a pump, and radioactive substances in the circulating water are analyzed. If there is a defect such as a crack in the reed or fuel tube, the radioactive material inside will leak into the circulating water and be detected. However, although this method allows the presence of defects to be known, it is not possible to know the location and condition of the defects. For this reason, defects in the fuel rods of the fuel assembly are detected by visual inspection of the outer periphery using the above-mentioned television camera.

However, this television camera could only detect defects in the outermost fuel rods of the fuel assembly.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to provide a fuel assembly visual inspection system fff that is capable of visually inspecting the fuel rods inside the fuel assembly. be.

That is, the present invention includes a visual inspection device main body that is moved up and down along a fuel assembly suspended in water, and a visual inspection device that projects from the visual inspection device main body and is inserted into the gap between the fuel rods of the fuel assembly. A fiber scope probe section that takes an image of the surface of a fuel rod and transmits this image through an optical fiber bundle, and a probe moving mechanism that moves this fiber scope probe section in a horizontal plane relative to the appearance inspection apparatus main body. It is something. Therefore, this 7-eye scope probe has a small diameter and is flexible, so it can be inserted into the gap between the fuel rods of the fuel assembly, and this fiber scope probe can be moved in a horizontal plane by the probe movement mechanism, so this fiber scope probe can be inserted into the gap between the fuel rods of the fuel assembly. The probe can be inserted at any position inside the fuel assembly, and the appearance of the fuel rods inside the fuel assembly can be easily and reliably inspected.

The present invention will be described in detail below with reference to the drawings. 1 to 10 show a first embodiment of the present invention. First, the first
This device will be schematically explained with reference to the figures.

That is, in the figure, 1 is a fuel assembly, and this fuel assembly is suspended by a crane hook 2 in water in a pit 3 such as an inspection pit or a spent fuel pit. This fuel assembly 1 includes an elongated frame 3.
7 is attached via clamps 39 and 4θ provided at both the upper and lower ends. The frame 37 allows the appearance inspection apparatus main body 4 to be moved up and down.

It is slidably guided along the axial direction of the fuel assembly l. In this appearance, the inspection device main body 4 is suspended by a wire rope 5 of a winch (not shown). This visual inspection device main body 4 includes a probe moving mechanism 6,
A fiberscope probe section 7 is provided. This device includes a fiberscope transmission section 8, an industrial television transmitter 9, and a light source H1 that sends light to the fiberscope.
0. A VTR 17 for recording the image from the transmitter 9 and a television receiver 12 for monitoring the image are provided.
The light source device 1θ, the VTR 71, and the television receiver 2 are placed on the operation floor J3. The fiber scope glove part 7 is inserted into the gap between the fuel rods 14, and can be moved in a horizontal plane by the probe drive mechanism 6. Also, the fiber scope glove part 7 can be moved in the horizontal plane by the probe drive mechanism 6, and can be inspected in the vertical direction by moving the wire row f5 up and down with a winch. It is moved together with the device main body 4. The probe section 7 is also configured to be able to be pulled out from between the fuel rods 14 and moved in a direction perpendicular to the plane of the paper. Further, by rotating the fuel assembly 1 by 180 degrees and performing the same inspection, the remaining half of the fuel rods 4 can be inspected. Hikoo 16 indicates a grid that binds the fuel rods 14.

Next, the structure of the appearance inspection apparatus main body 4 will be explained with reference to FIGS. 2 to 7. That is, this appearance inspection device main body 4
The support plate noah is connected and fixed with guide rod No. 8 to form a frame that becomes the pace. A comb fitting 9 is passed through the guide rod 18. The metal fitting J9 is connected to the connecting plate 2 via the connecting metal fitting 20, and the connecting plate 2 connects the two connecting metal fittings 20 to integrate them. A bevel guide member 22 is fixed under the connecting plate 2, and a slider 23 is slidably fitted in the bevel guide member 22. The slider 23 is additionally equipped with the aforementioned fiberscope glove section 7. In addition, the cylinder 24 has two connecting fittings 20
The rod 25 of the piston is connected to one end of a connecting rod 27 via a connecting piece 26, and the other end is fixed to the slider 23 described above. In addition, spring 2
8 is for buffering the fiber scope glove portion 7. and.

If piston rod 25 is moved in the direction of arrow
2 in the direction of the arrow X, the fiberscope probe section 7 is moved in the direction of the arrow X. Further, a piston cylinder 29 is inserted and fixed between two supporting plates, and a rod 30 of the piston is connected to one end of a connecting rod 32 via a connecting piece 3, and the other end is connected to one end of a connecting rod 32. Fixed. Therefore, by moving the piston rod 30 in the direction of the arrow Y, the connecting rod 32 can be moved in the direction of the arrow Y via the connecting piece 3, and the connecting rod 32 is fixed to one of the fittings 9. Since it is, you can move this as well. Since the two comb fittings 19 are connected by the connecting plate 2, the two comb fittings 19 are simultaneously guided by the guide rod 18 together with the connecting plate 2 and moved in the direction of arrow Y. Further, since the sliding guide member 22 is fixed to the connecting plate 2, the sliding guide member 22 also moves in the direction of the arrow Y together with the slider 23 fitted therein. Therefore, the fiberscope probe section 7 attached to the slider 23 can be moved in the direction of the arrow Y.

Note that the spring 83 is for buffering the fiberscope glove portion 7 in the Y direction.

Further, on the two support plates J7, a shim plate 34 is fixed, and a metal fitting 35 is attached to the shim plate 34. Further, the side surface of the support plate 12 has a guide ear 3 having a hole.
6 is attached and the guide post 38 fixed to the frame 37 mentioned above is passed through the hole of the guide bracket 36.

Therefore, this visual inspection device is movably attached to the four-piece frame 37. Therefore, the hanging metal fitting 35 is lowered with a wire rod and the visual inspection device main body 4 is attached to the guide column 3 using a winch.
8, the 7-eye path scoop glove portion 7 can also be moved in two directions, that is, in the up and down directions. Then, the frame 37 with the above-mentioned appearance inspection device 4 attached is lowered with a winch (not shown) and brought close to the fuel assembly, and the uppermost and lowest grid slots are gripped with 2 pumps 39.40. is configured to do so.

Four upper nozzles are attached to the upper end of the fuel assembly 1, and a lower nozzle 42 is attached to the lower end. In FIG. 1 is lowered into the water of the bit. Furthermore, when the frame 37 is suspended by a winch (not shown) and brought close to the fuel assembly J, the lower end of the frame 37 is tilted to the fuel assembly J first by the tilting device 44 using buoyancy.
After the lower end clamp 40 of the frame 37 contacts the fuel assembly 1, if the frame 32 is gradually brought closer to the fuel assembly J, the upper clamp 39
In this state, cranks f, 99 and 40 can tighten the grid 16, thereby tightening the frame 37 and fuel assembly 1.
It is structured so that additional issues can be published in parallel.

45 is a piston cylinder 24. : Shows the hydraulic or pneumatic hose for z9.49, and the hose for piston cylinder 49 has a cover 46.

Further, the structure of the clamp 39 is shown in FIGS. 8 to 10. That is, an L-shaped frame 47 attached to the frame 37 has an additional plate 48 for applying it to the grid 16 of the fuel assembly J.
The frame 37 is brought closer to the fuel assembly 1 while visually inspecting it using the illumination light and television camera (both not shown) attached to the grid 7, and the relative position between the clamp 39 and the uppermost grid The contact plate 48 is configured to be brought into contact with the contact plate 48. Then, the rack 5o is moved by the cylinder 49, the pinion 5o is rotated, and the shaft 52 is rotated.
The grip PJ6 is pressed from two directions with a presser foot 53 fixed to the grip PJ6. Okay, lower end clamp 4
0 also has the cylinder 49, rack 5o and binion 51 in the frame 4.
Clamp 39 as described above except that it is attached to the underside of 7.
It has the same structure as . By tightening the lowermost grid 16 with the clamp 4o similar to the clamp 39, the frame 37 can be firmly attached to the fuel assembly 1.

In the first embodiment of the present invention configured as described above, the fiber Skog probe section 7 is inserted into the gap between the fuel rods 10 and 14, and the grid 16 and the grid 16 are connected to each other for each fuel rod 4. After inspecting from bottom to top between
The next fuel rod 14 is inspected, and when that row is finished, the fiberscope probe section 7 is pulled out and inserted into the next gap, and the same inspection is carried out, and when one section between the grids is finished, it is moved to the next section. If the entire length of the fuel assembly is inspected, half of the fuel rods 14 will be inspected over the entire length.

Also, remove the frame 37 from the fuel assembly, rotate the fuel assembly 1 180°, add the frame 32 again,
If the same inspection as above is carried out, the fuel rod 1 inside the fuel assembly
It is possible to carry out 9 visual inspections over the entire length of 4.

The addition and removal of Naori Ranno 39 and 40, and the operation of the fiberscope probe section 7 are all carried out in deep water, so the illumination lights and TV camera (not shown) attached to the frame 32 are used while watching TV. It will be done.

The state of the fuel rods projected by the fiberscope globe section 7 is recorded on the VTR 1 via the fiberscope transmission section 8 by the action of the industrial television transmitter 9 and the light source device Jθ, and is also recorded on the television. It can be confirmed by displaying it on the display J2.

Note that FIG. 11 shows a second embodiment of the present invention. In this second embodiment, the frame 37 of the first embodiment is omitted, and the appearance inspection device main body 4 is replaced by a crane wire rope 5.
The structure is similar to that of the first embodiment described above, except that the appearance inspection apparatus main body 4 is directly suspended by the crane and raised and lowered up and down by the crane. Note that in FIG. 11, parts corresponding to the first embodiment are designated by the same reference numerals, and the explanation thereof will be omitted.

As described above, the present invention comprises a visual inspection device h'' main body that is moved up and down along a fuel assembly suspended in water, and a gap between the fuel rods of the fuel assembly that is protruded from the visual inspection device main body. A fiberscope probe unit is inserted into the fuel rod to take images of the surface of these fuel rods and transmits this image through an optical fiber bundle, and a globe movement unit moves the fiberscope probe unit in a horizontal plane with respect to the above-mentioned appearance and inspection equipment body. This fiberscope probe has a small diameter and flexibility, so it can be inserted into the gap between the fuel rods of a fuel assembly, and the probe moving mechanism allows the fiberscope probe to be moved on a horizontal surface. Since the fiber scope can be moved inside the fuel assembly, it is possible to enter the glove part, and the appearance of the fuel rods inside the fuel assembly can be easily and reliably inspected.

[Brief explanation of drawings]

1 to 10 show a first embodiment of the present invention, in which FIG. 1 is a schematic diagram of the overall configuration, FIG. 2 is a side view of the appearance inspection device main body and frame, and FIG. 3 is the same as that of FIG. 11-■ Arrow view,
Fig. 4 is a perspective view of the visual inspection device main body, Fig. 5 is a plan view of the visual inspection device main body, Fig. 6 is a view taken along the V+-V+ arrow in Fig. 5, and Fig. 7 is a -■-■ diagram in Fig. 5. 8 is a plan view of the clamp, FIG. 9 is a side view of the clamp, and FIG. 1013 is a view taken along the line X--X in FIG. 9. FIG. 11 is a schematic diagram of a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Fuel assembly, 3... Pit, 4... Appearance inspection device main body, 6... Globe moving mechanism, 8... Fiber scope glove part, 2... Television receiver, 1
4... Fuel rod, 18... Guide rod, 23... Slider, 24.29... Piston cylinder, 37... Frame, 38... Guide column, 39.40... Clamp. Applicant Sub-Agent Patent Attorney Takehiko Suzue 14- Figure 7 ■ Figure 5 Figure 6 Figure 8

Claims (1)

[Claims] A visual inspection device body that is moved up and down along a fuel assembly suspended in water, and a visual inspection device that protrudes from the visual inspection device body and is inserted into the gap between the fuel rods of the fuel assembly and inspects the surface of these fuel rods. The present invention is equipped with a fiberscope probe section that takes an image of the object and transmits the image through an optical fiber bundle, and a glove movement mechanism that moves this fiberscope glove section in a horizontal plane with respect to the above-mentioned external appearance and the main body of the inspection device. Appearance inspection device for fuel assemblies that determines percentage characteristics.