JP2763438B2 - Radiation transmission test equipment for double pipe structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double pipe structure for a nozzle weld of an internal pump (hereinafter referred to as "RIP") attached to a lower part of, for example, an ABWR type reactor pressure vessel (hereinafter referred to as "RPV"). The present invention relates to an apparatus for inspecting by a test.

[0002]

2. Description of the Related Art Conventionally, as a radiation source for a radiation transmission test,
Using a radioisotope or a panoramic X-ray generator, the source position (the focal position in the case of the X-ray generator) is so simple that it is located inside the inner tube and almost opposite to the welding position of the inner tube. Position using a support, attach a rectangular film to the tip of a thin rod, etc., and insert it through the access opening in the gap between the inner and outer pipes so that it is almost outside the welded part, and shoot one by one However, it was impossible to perform a precise inspection, such as evaluating the size of the protrusion of the back surf from the film density.

[0003]

The degree of defect discrimination in a transmission photograph obtained by a radiation transmission test of a metal material is generally superior to that obtained using an X-ray generator than that obtained using a radioisotope. I have. In inspection of important structures such as RPV, it is necessary to take an image with an X-ray generator having a high degree of defect discrimination.

[0004] On the other hand, in an internal source imaging method of a circumferential weld, in order to perform a precise inspection such as evaluating a protrusion size of a back side from a film density, a relative relationship between a weld position and a source position is required. Must be arranged and photographed uniformly over the entire circumference. In the above-mentioned prior art, it is difficult to finely adjust the focal position of the panoramic X-ray generator on the center axis of the inner tube and on a plane formed by the welding center axis with high accuracy. Also, since the gap between the pipes is narrow, and one of the gaps is closed, a rectangular film is to be installed from the access opening at a position several tens of times apart from the gap size, It is difficult to wrap the film around the entire periphery of the weld while wrapping the end. Therefore,
The entire circumference is divided into several shots, and it is difficult to uniformly set the positional relationship between each film and the weld.

A first object of the present invention is to inspect a double tube structure using a panoramic X-ray generator by setting the focal position of the panoramic X-ray generator on the center axis of the inner tube, and An object of the present invention is to provide a radiation transmission test apparatus capable of positioning accurately on a plane formed by a welding central axis.

A second object of the present invention is to avoid double divisional imaging in inspection of a double tube structure using a panoramic X-ray generator, to enable simultaneous imaging of the entire circumference, and to achieve an annular shape. It is an object of the present invention to provide a radiation transmission test apparatus capable of accurately positioning a film holder that can be assembled and disassembled in a gap between an outer tube and an inner tube.

[0007]

SUMMARY OF THE INVENTION In order to achieve the first and second objects, the present invention provides a method for manufacturing a vehicle, wherein the gap between the inner pipe and the outer pipe is narrow, and at least one of the gaps is closed. In a radiation transmission test apparatus of a double pipe structure for performing a radiation transmission test on a welded portion of an inner pipe of a double pipe structure having an access opening in an outer pipe, a panoramic X-ray generator, A first device for positioning the focal position of the X-ray generator on the center axis of the inner tube and on a plane formed by the welding center axis, and a gap between the outer tube and the inner tube through the access opening; A second device for positioning an annularly formed film on the outside of the inner tube welded portion of the second device,
Is a ring that can be assembled and disassembled annularly at the access opening.
Film holder and opening for film holder access
Has a belt that can be moved to a predetermined position by operation from the
And an access opening that forms a guide for movement.
An arm that can be raised and disassembled and this access opening
Standing and disassembly is possible, and arm can be attached and detached.
That having a and possible support ring.

Further, in the above-mentioned radiation transmission test apparatus,
The first device preferably includes first positioning means for positioning the focal position of the panoramic X-ray generator on the central axis of the inner tube, and the focal position of the panoramic X-ray generator is formed by the welding central axis. Second positioning means for positioning on a plane to be formed, wherein the first positioning means has a guide member whose guide surface is a tapered surface having a center line on a focal position, and A guide portion of a double pipe structure having a tapered surface with which a guide surface is fitted, wherein the second positioning means drives a panoramic X-ray generator in the pipe axis direction and is formed by a welding central axis. It is composed of a drive mechanism for positioning on a plane to be formed.

[0009]

[0010]

Further, in the radiation transmission test apparatus, preferably, a rack for rotating the film holder and the arm by an operation from the access opening is cut on an outer periphery of the support ring.

[0012]

Further, in order to achieve the second object, the present invention provides a radiation transmission test apparatus, comprising: a film holder which can be assembled and disassembled in an annular shape at the access opening; have a means for positioning on the outside of the inner tube weld gap between the outer tube and the inner tube through the access opening, the positioning means, the film
Operate the holder from the access opening to the specified position.
Having a belt to be moved by means of
Arm that can be assembled and disassembled with an access opening,
Assembly and disassembly are possible with this access opening, and
Arm mounting and dismounting Ru <br/> be possessed a support ring possible.

[0014]

According to the present invention, by providing the first device having the above structure, the focal position of the panoramic X-ray generator is accurately positioned on the center axis of the inner tube, and the panoramic X-ray generator is provided. Can be accurately positioned on a plane formed by the welding central axis. Further, by providing the second device having the above configuration, the film holder capable of being assembled and disassembled in an annular shape at the access opening can be used to weld the film between the outer tube and the inner tube through the access opening. Can be positioned accurately outside the part.

[0015]

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

FIG. 1 shows an ABWR type reactor pressure vessel ( hereinafter referred to as R).
PV hereinafter) 1 is a cross-sectional view of the whole. R PV1 includes a nozzle portion 1A which a through hole is formed, the reactor pressure vessel internal pump (hereinafter RIP hereinafter) casing 2 has a structure which is inserted into the through hole of the nozzle portion 1A. FIG. 2 shows a detailed sectional view of this part. The RIP casing 2 is welded in the middle of the through hole via the nozzle portion 1A and the welding portion 3. This welded portion forms a double pipe structure, the gap between the pipes is narrow, and one (upper end) of the gap is closed. The other end (lower end) of the gap is also closed, but the nozzle portion 1 of the RPV 1 corresponding to the outer tube
A is provided with an opening 4 for access into the gap.

The apparatus according to the present embodiment is for performing a radiation transmission test on the welded portion 3, and its overall configuration is shown in FIGS.
Shown in In the radiation transmission test of the welded part 3 by the apparatus of the present embodiment, the panoramic X-ray generator 5 is installed inside the nozzle,
The film is removed from the access opening 4 through the RIP casing 2.
And positioning it in the gap between the nozzle of RPV1 and shooting
This is performed by the so-called internal source method. Hereinafter, the device of this embodiment will be described in detail.

The radiation transmission test apparatus of the present embodiment comprises a radiation source positioning device 50 shown in FIG. 3 and a film positioning device 51 shown in FIG.

In FIG. 3, the source positioning device 50 is
X-ray generator holding support 7 and X-ray generator driving mechanism 8
A guide member 7A (shown in an umbrella shape in the figure) having a tapered surface is provided at the bottom of the X-ray generation device holding support 7, and the X-ray generation device driving mechanism 8 includes a motor 8
a , a nut 10 for vertical movement and a detent 11.

The panoramic X-ray generator 5 is connected to an X-ray generator driving mechanism 8 via an X-ray generator holding support 7. The panoramic X-ray generator 5, the X-ray generator driving mechanism 8, and the X-ray generator holding support 7 are previously assembled integrally. At the time of this assembling, assembling bolts, screws, and liners (not shown) such that the central axis of the panoramic X-ray generator 5 at the focal position 6 in the tube axis direction coincides with the central axis of the tapered surface of the guide member 7A. Fine-tune with. Here, a guide portion 1B having a tapered surface into which the tapered surface of the guide member 7A fits is formed at the upper end of the nozzle portion 1A. When the guide member 7A is positioned at the upper end of the nozzle, the guide member 7A
And the central axis of the nozzle necessarily coincides with the central axis of the nozzle. Accordingly, when the guide member 7A is positioned at the upper end of the nozzle, as a result, the central axis of the panoramic X-ray generator 5 at the focal position 6 in the tube axis direction coincides with the central axis of the nozzle. The work of positioning the central axis is greatly simplified.

After positioning the X-ray generator holding support 7 on the upper end of the nozzle of the RPV 1, the X-ray generator driving mechanism 8 is operated. A screw is cut at the tip of the rotating shaft 9 of the X-ray generator driving mechanism 8, and a nut 10 for vertical movement is engaged with the screw, and the rotation is restrained by a detent 11, so that a panoramic X-ray generation is performed. Fine adjustment of the vertical movement of the container 5 is performed. Therefore, by operating the X-ray generator driving mechanism 8, the focal position 6 can be easily adjusted on a plane formed by the welding central axis.

On the other hand, the film positioning device 51
As shown in FIG.
3. It is composed of an assembled ring type film holder 14.

The assembling type support ring 12 can be divided into several ring segments 12A and 12C in the circumferential direction, and is inserted one by one from the access opening 4 and connected to each other to form a ring-shaped portion under the gap. Assemble to 12
C is one ring segment having a connection portion with the assembling arm 13, and 12 A is a plurality of ring segments having no connection portion with the assembling arm 13. These inner diameters are slightly larger than the outer diameter of the RIP casing 2,
The outer diameter is slightly smaller than the inner diameter of the nozzle of the RPV 1, and a rotation rack is cut on the outer periphery of each.

The assembled ring type film holder 14 is
Similarly to the assembling type support ring 12, those divided into several holder segments 14A and 14B in the circumferential direction are inserted one by one from the access opening 4 and connected to each other to be assembled into a ring shape. 14B is an assembling arm 13
And two holder segments having a connection portion with
14A is a plurality of holder segments having no connection with the assembling arm 13. Holder segment 1
The connecting portion is released so that the roll film 16 packed in the pack is taken in and out so that 4B is located at the position of the access opening 4. At this time, the roll film 16 having a length corresponding to the circumferential length of the assembled ring type film holder 14 is packed in a pack, and the roll film 16 is pushed along the groove of the assembled type ring type film holder 14 to be easily mounted. Can be. FIG. 5 shows a cross-sectional view of this mounted state.
Each of the holder segments 14A and 14B has a U-shaped cross section, and the roll film 16 is pushed into the groove between them.

Each of the assembling arms 13 has an arm segment 13A, 1A having a length such that the length of each arm can enter through the access opening 4 and can be assembled by the access opening 4.
The structure can be divided into 3B and 13C. 13B is an uppermost one arm segment having a connection portion with the assembling ring type film holder 14, 13C is a lowermost one arm segment having a connection portion with the assembling support ring 12, 13A is a plurality of arm segments located between 13B and 13C, which do not have a connection with the assembling type support ring 12. When all of them are assembled, the tip of the uppermost arm segment 13B reaches the upper end of the gap. FIG. 6 is a plan view of the uppermost arm segment 13B and the assembled ring type film holder 14, and FIG. 7 is a sectional view of the lowermost arm segment 13C. Each of the arm segments 13A, 13B, and 13C forms a guide that allows the assembling ring-shaped film holder 14 to move up and down, and has toothed rollers 18, 24 incorporated in the uppermost arm segment 13B and the lowermost arm segment 13C. The moving toothed belt 17 is rotated by the belt, and the assembled ring type film holder 14 fixed to the slider 19 can be moved up and down. The lowermost arm segment 13C is a drive shaft end 15 for rotating the moving toothed belt 17.
have.

The procedure for assembling the assembling type support ring 12, the assembling type arm 13, and the assembling type ring type film holder 14 of the film positioning apparatus will be described below. First, the ring segments 12A and 12C are inserted one by one from the access opening 4, and the assembling type support ring 12 is assembled. At this time, the ring segment 12C is previously assembled integrally with the arm segment 13C having the drive shaft end 15, and is inserted last through the access opening 4 to assemble the assembling type support ring 12. Next, the holder segments 14A and 14B are similarly inserted one by one from the access opening 4, and the ring type film holder 14 is assembled.
Assemble. Similarly, at this time, the holder segment 14B
Is assembled in advance integrally with the uppermost arm segment 13B, and is finally inserted through the access opening 4 to assemble the assembling type film holder 14.
The mounting of the film is performed immediately before mounting the holder segment 14B. After assembling the assembling type support ring 12 and the assembling type ring type film holder 14, the assembling type arm 13 is attached. Uppermost arm segment 13
The arm segments 13A are inserted one by one from the access opening 4 while lifting the assembling type film holder 14 with B, and finally the arm segments 13C integrated with the assembling type support ring 12 are connected and assembled. The expression arm 13 is completed. The film positioning device 51 is assembled according to such a procedure.

A bevel gear 22a is attached to the drive shaft end 15, and the power from the assembling ring type film holder up / down drive mechanism 20 meshes with the bevel gear 22b attached to the tip of the flexible shaft 23 so that the drive shaft end 15 is driven. It is conveyed to 15. As a result, the assembled ring-type film holder 14 with the film mounted thereon moves upward in the gap. Assembled ring type film holder 14
Can be easily adjusted from the relationship between the number of rotations of the drive shaft end 15 and the amount of movement of the holder.

On the other hand, as shown in FIG. 8, the assembling type support ring 12 uses a rack cut on the outer periphery and uses the film positioning mechanism controller 2 at the position of the access opening 4.
6 by the assembling ring rotating mechanism 25 that operates according to the command
It can rotate in the gap. Assembling type support ring 12
Is rotated, the assembling arm 13 and the assembling ring type film holder 14 also rotate within the gap. From the position of the assembling arm 13, the relative positional relationship between the circumferential position of the welded portion and the image of the welded portion projected on the film can also be easily compared. That is, at the time of local photographing using a short film after photographing the entire periphery of the welded portion, the assembling ring type film holder 14 previously assembled in an annular shape at the access opening 4 is connected to the outer tube and the inner tube. From the access opening 4 of the gap, positioning can be accurately performed outside the target portion of the inner pipe welded portion.

FIG. 9 is a block diagram of the entire apparatus of the present embodiment. The motor 8a of the X-ray generator driving mechanism operates according to a command from the X-ray generator driving mechanism controller 27, and detects the vertical position of the panoramic X-ray generator 5 based on a signal from the X-ray generator driving mechanism 8. I do. Assembling type ring rotation mechanism 25
Operates according to the command of the film positioning mechanism controller 26 to rotate the assembly type support ring 12 as described above. The assembling ring type film holder vertical drive mechanism 20
Operated by a command from the film positioning mechanism controller 26, the assembling ring type film holder 14 is moved up and down. Assembled support ring 1 based on signal from assembled ring rotation mechanism 25
The rotation angle of 2 can be determined by a signal from the assembling ring holder vertical drive mechanism 20.
Can be detected by the film positioning mechanism controller 26.

After adjusting the panoramic X-ray generator 5 and the assembled ring type film holder 14 to predetermined positions,
By operating the line generation controller 28, X-rays are generated and the imaging state is set.

According to this embodiment, the panoramic X-ray generator 5 is positioned at the upper end of the nozzle with the guide member 7A adjusted so that the central axis thereof coincides with the central axis in the tube axis direction at the focal position 6 of the panoramic X-ray generator 5 so that the panoramic X-ray generator 5 is positioned. The focal position 6 of the expression X-ray generator 5 can be accurately positioned on the central axis of the inner tube. Furthermore, X
By operating the line generator driving mechanism 8, the focal position 6 of the panoramic X-ray generator 5 can be accurately positioned on a plane formed by the welding center axis. Further, the film is mounted on the assembling ring type film holder 14 and the assembling type support ring 12 which is rotatable by itself and the assembling arm 13 having the moving toothed belt 17 are connected to the assembling type film holder. The ring type film holder 14 can be accurately positioned outside the welded portion of the inner tube in the gap between the outer tube and the inner tube through the access opening 4. Therefore, it is possible to avoid several times of divisional imaging, to perform simultaneous imaging of the entire circumference, and to perform a highly accurate inspection of the welded portion of the inner pipe.

[0032]

According to the present invention, in the inspection of a double tube structure using a panoramic X-ray generator having a high degree of defect discrimination, the focal position is set on the center axis of the inner tube and on the center axis of the weld. It is possible to accurately position a film holder which can be positioned accurately on a plane to be formed, and which can simultaneously shoot the entire circumference by avoiding several divisional shootings. Therefore, high-precision inspection of the welded portion of the inner pipe is possible, and the fine adjustment mechanism reduces the time required for setting the radiation source. This is effective in improving the efficiency and economy.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an entire ABWR type RPV 1. FIG.

FIG. 2 is a detailed view of a welded portion of a RIP casing 2;

FIG. 3 shows a radiation source positioning device 5 according to an embodiment of the present invention.
0 is a sectional view.

FIG. 4 is an external view of a film positioning device 51 according to one embodiment of the present invention.

FIG. 5 is a cross-sectional view of the holder segment 14A of FIG.

FIG. 6 is a plan view of the arm segment 13B and the holder segment 14A of FIG.

FIG. 7 is a cross-sectional view of the arm segment 13C of FIG.

FIG. 8 is a perspective view of the assembled ring rotating mechanism 25.

FIG. 9 is a block diagram of the entire apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ABWR type reactor pressure vessel 1A Nozzle part 1B Guide part 7 X-ray generator holding support 7A Guide member 8 X-ray generator drive mechanism 8a Motor 9 Rotary shaft 10 Vertical movement nut 11 Detent 12 Assembly type support ring 12A, 12C Ring segment 13 Assembled arm 13A-C Arm segment 14 Assembled ring type film holder 14A, 14B Holder segment 15 Drive shaft end 17 Toothed belt for movement 18 Toothed roller 19 Slider 20 Assembled ring type film holder vertical drive mechanism 22a, 22b Bevel gear 23 Flexible shaft 24 Toothed roller 25 Assembled ring rotation mechanism 26 Film positioning mechanism controller 27 X-ray generator drive mechanism controller 28 X-ray generation controller 50 Source positioning device (first device) 51 Ilm positioner (second device)

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01B 15/00-15/06 G21C 17/00-17/14

Claims (4)

(57) [Claims] A gap between an inner pipe and an outer pipe is narrow, at least one of the gaps is closed, and an inner pipe welding portion of a double pipe structure having an access opening in the outer pipe. In a radiation transmission test apparatus of a double pipe structure for performing a radiation transmission test by using a panoramic X-ray generator, the focal position of the panoramic X-ray generator is set on the central axis of the inner tube and with the welding central axis. A first device for positioning a film formed on a plane to be formed, and a second device for positioning a film formed in an annular shape outside the inner pipe welding portion in a gap between the outer pipe and the inner pipe through the access opening. is composed of a, the second device is set in an annular shape at said access opening
A film holder that can be set up and disassembled, and the film holder
Position the holder by operating it from the access opening.
With a belt to move to
That can be assembled and disassembled at the access opening.
And the access opening can be assembled and disassembled.
And a support ring capable of attaching and detaching the arm.
Radiographic examination apparatus according to claim Rukoto to have a. 2. A radiation transmission test apparatus for a double pipe structure according to claim 1, wherein said first apparatus is a panoramic X-ray apparatus.
First positioning means for positioning the focal position of the line generator on the central axis of the inner tube, and second positioning means for positioning the focal position of the panoramic X-ray generator on a plane formed by the welding central axis Wherein the first positioning means comprises a guide member having a guide surface having a tapered surface having a center line on a focal position, and a taper surface to which the guide surface of the guide member fits. The second positioning means comprises a driving mechanism for driving the panoramic X-ray generator in the pipe axis direction and positioning the panoramic X-ray generator on a plane formed by the welding center axis. A radiation transmission test apparatus characterized by being performed. 3. The radiation transmission test apparatus for a double-pipe structure according to claim 1 , wherein the support ring is formed by cutting a rack for rotating the film holder and the arm by an operation from the access opening. A radiation transmission test apparatus characterized in that: 4. A gap between an inner pipe and an outer pipe is narrow, at least one of the gaps is closed, and an inner pipe weld of a double pipe structure having an access opening in the outer pipe. A radiation transmission test apparatus having a double tube structure for performing a radiation transmission test by using a film holder that can be assembled and disassembled in an annular shape at the access opening, and removing the film holder through the access opening. have a means for positioning on the outside of the inner tube weld gap between the tube and the inner tube, the position
Determining means for opening the film holder for the access.
There is a belt that can be moved to a predetermined position by operating from the mouth.
And said access opening forming a guide for movement
Arm that can be assembled and disassembled in the part, and the access opening
Can be assembled and disassembled with the arm.
Remove radiographic examination apparatus, wherein a is closed and the supporting ring possible.