JPH0469568A - Inspection device for nuclear reactor pressure vessel - Google Patents

Abstract

PURPOSE:To enable nondestructive inspection nearby a weld line even if the weld line is formed in a narrow place by rotating a rotary support table vertically and switching its attitude. CONSTITUTION:When the inspection device for the nuclear reactor pressure vessel needs to be inserted into a narrow part, etc., the length direction of the rotary support table is set to the up-down direction as an inserting direction through the operation of a rotary driving means 15 and the rotary support table 16 is passed through the narrow part; and then the rotary driving means 15 is put in operation again to change the length direction of the rotary support table 16 to the horizontal direction, and the fixation and position setting of respective parts are performed. An inspection equipment 17 is put in scanning motion in a target direction by the circumference-directional movement of the nuclear reactor pressure vessel 1 by a travel means 18 and the up-down movement by an elevation driving means 13 to perform the nondestructive inspection.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inspection device for a nuclear reactor pressure vessel, and in particular, the present invention relates to an inspection device for a nuclear reactor pressure vessel. This is to conduct a wall inspection.

"Prior Art J" As shown in FIGS. 6 to 8, inside a reactor pressure vessel 1 such as a boiling water reactor, a reactor core 2, a tsuyuroud 3,
A core tube 4, a jet pump 5, various piping, etc. are provided.

As shown in FIG. 7, the side wall of the reactor pressure vessel 1 has a structure in which a plurality of steel plates are joined together at welding lines W. Although the soundness of the pressure vessel 1 was sufficiently confirmed during manufacture, it is necessary to repeatedly confirm the soundness of welded joints and their vicinity during periodic inspections.

Conventionally, during periodic inspections, etc., each welding point (for example, the 7th
When the weld line W) in the illustrated example is subjected to destructive inspection, it is carried out by, for example, bringing a probe of an ultrasonic flaw detector into contact with the outer surface of the reactor pressure vessel 1.

"Problem to be Solved by the Invention" However, after the nuclear reactor is in a state where construction is completed, many piping and equipment are installed around the reactor pressure vessel l, so the outside of each weld line W is There may be cases where it is not possible to secure space for inspection. In such a situation, inspection equipment must be inserted into the reactor pressure vessel 1, but as mentioned above, there are various types of equipment inside the reactor pressure vessel 1. Therefore, the welding line W between the jet pumps 5 and the like becomes a narrow space, which is accompanied by technical difficulties. Such equipment for inspecting the narrow space inside the reactor pressure vessel 1 has not yet been developed.

An object of the present invention is to enable destruction inspection in the vicinity of the weld line even when the weld line is formed in a narrow space such as between internal structures of a reactor pressure vessel. It is something.

``Means for Solving the Problem J'' In order to solve the problem, the system is suspended from the upper edge of the internal structure of the reactor pressure vessel, and the lower end is inserted into the vicinity of the inspected part of the reactor pressure vessel. a lifting guide rod disposed along the vertical direction on the supporting stand; a moving stand that is vertically movably supported by the lifting guide rod and moved up and down by an lifting drive means; A rotary support table that is vertically rotatably supported and whose posture can be changed by a rotary drive means and given a difference in vertical and horizontal dimensions, and a rotary support table that is movably supported in its longitudinal direction and inspects the inner surface of a reactor pressure vessel inspection equipment,
The reactor pressure vessel inspection apparatus is configured to include a traveling means mounted on a rotating support table and for moving the inspection equipment along the inspection site.

"Operation J: When inserting inspection equipment into the reactor pressure vessel, this is done by suspending the support pedestal from the upper edge of the internal structure. When the lifting drive means is activated, the movable pedestal is connected to the lifting guide rod. Move up and down along.

When inserting the inspection device into a narrow space, the rotation drive means is operated to align the longitudinal direction of the rotating support with the vertical direction, so that it can be easily inserted into or passed through the narrow space. As the process progresses, after inserting the rotating support into the required location, align the longitudinal direction of the rotating support with the inspection direction,
Thereafter, a destructive inspection is performed by scanning the inspection equipment in the target direction using the traveling means and the elevating drive means.

"Embodiment" Hereinafter, an embodiment of the reactor pressure vessel inspection apparatus according to the present invention will be described with reference to FIGS. 1 to 8.

In the figure, reference numeral 10 is a reactor pressure vessel inspection device, 11 is a support frame, 12 is an elevating guide rod, 13 is an elevating drive means,
14 is a moving frame, 15 is a rotation drive means, 16 is a rotation support base, 17 is an inspection device, 18 is a traveling means, 19 is an upper fixing means, 20 is a lower fixing means, 21 is a scanning position sensor, 2
2 is an underwater camera.

The support frame 11, as shown in FIGS. 1 and 2,
Lifting tool 23 for suspending the entire reactor pressure vessel l
a hook stopper 24 that is placed on the upper edge of the core shroud 4, which is one of the internal structures of the core shroud 4, and is attached in a suspended state;
The hook includes a hook part 25 located outside the stop part 24, a lifting guide rod 12 arranged along the top and bottom to guide the movable platform 14 downward, and a core installed on the hook part 25. An upper fixing means 19 consisting of an air cylinder or the like for horizontally holding the shroud (internal structure) 4; An insertion guide section 26 for positioning; a lower fixing means 20 consisting of an air cylinder or the like disposed near the insertion guide section 26 and for positioning by pressing against the outer peripheral surface of the internal structure 4; It has a guide roller 27 which is integrally attached near the insertion guide part 26 and rolls on the inner surface of the reactor pressure vessel l to facilitate vertical movement.

As shown in FIGS. 1 and 2, the lifting drive means 13 is rotated and moved by a rotational drive source 28 such as an electric motor mounted on the upper part of the support frame 11. It has a ball screw 29 that screws into the ball nut portion of the pedestal 14.

The movable frame 14, as shown in FIGS. 3 and 4,
The mounting that is attached to the ball nut of the lifting drive means 13 is a bracket 30, the link mechanism 31 supported by the bracket 30, and the support base that is attached to the tip of the link mechanism 31 and connected to the rotation drive means 15. 32
A pair of parallel cylinders 33, which are interposed between the bracket 30 and the support stand 32 and are made of an air cylinder or the like for drawing out the support stand 32 horizontally outward, are also attached to the bracket 30 and the support stand 32. and a pressing spring 34 that is interposed between the support base and the support base and moves the support base horizontally outward by a resilient force.

As shown in FIG. 3, the rotation drive means 15 is, for example, a stepping motor mounted on a movable frame, and is used to vertically rotate the rotation support 16 back and forth within a range of 180 degrees.

As shown in FIGS. 4 and 5, the rotation support table 16 includes a narrow support plate 35 that is vertically rotated by the rotation driving means 15, and a support plate 35 that slightly protrudes from both ends of the support plate 35 in the longitudinal direction. A pair of side frames 36 provided in the same direction, a pair of parallel guide rods 37 installed between the pair of side frames 36, and a running device for scanning and moving the inspection equipment 17 along the guide rods 37. means 18 and a scanning position sensor 21 for detecting the scanning position of the testing device 17;
It is Shino who has. The traveling means 18 includes a rotary drive source 38 mounted on the support plate 35 and a rotary drive source 38 mounted on the support plate 35.
a ball screw 39 rotated by the rotational force of 8;
It has a feed block 40 that is screwed onto the ball screw 39 and on which the inspection equipment 17 is mounted, and the scanning position sensor 21 is composed of a rotary encoder or the like that detects the rotation angle of the ball screw 39. be.

Note that, as shown in FIG. 2, the underwater camera 22 is installed at an appropriate location such as the lower part of the support pedestal 11 so as to image the lower part when inserted.

In the reactor pressure vessel inspection device configured as described above, the inspection device 17 is inserted into the reactor pressure vessel l,
When performing a non-destructive inspection near the weld line (inspection target location) W, the insertion guide section 26 at the bottom of the support frame 11 is appropriately selected and adapted to the guide 113a of the shroud 3, etc. 23 to suspend the inspection equipment 17 into the narrow space outside the core shroud 3 in the reactor pressure vessel 1, position it using the insertion guide part 26, and attach the hook stop part 24 to the core shroud 4. The device is placed on the upper edge of the device and suspended as a whole, as shown in FIGS. 1 and 2.

When it is necessary to insert the reactor pressure vessel inspection device 10 into a narrow space as shown in FIG. After passing through the narrow part in the vertical direction, the rotary drive means 15 is operated again to align the longitudinal direction of the rotary support base 16 with the horizontal direction, as shown in FIG. Fixation and position settings are performed.

The support pedestal 11 is fixed by the upper fixing means 19 and the lower fixing means 20, and the height of the inspection equipment 17 supported by the movable pedestal 14 is set by operating the lifting drive means 13, as shown in FIG. As shown, due to the operation of the link mechanism 31 and the elastic force of the suppression spring 34, the inspection equipment 1
7 is brought out so as to come into contact with the inner surface of the reactor pressure vessel 1, and then the inspection equipment 17 is moved by moving in the circumferential direction of the reactor pressure vessel 1 by the traveling means 18 and moving in the vertical direction by the lifting drive means 13. Destructive inspection is performed by scanning in the target direction.

Then, at each target position, as shown by the arrows in FIG. 5, ultrasonic waves are irradiated in the right direction from the inspection equipment I7 at three locations, for example, at an incident angle of 0 degrees, an incident angle of 45 degrees, and an incident angle of 60 degrees. Ultrasonic manipulation testing will be performed. Furthermore, when the rotating support base 16 is rotated 180 degrees, the direction of ultrasonic irradiation is to the left, and by rotating the orientation of the inspection machine and instrument 17 by 90 degrees clockwise or counterclockwise, The ultrasonic irradiation direction is upward or downward, and ultrasonic flaw detection can be performed on the inspection target location (welding line) W from four directions.

On the other hand, when the reactor pressure vessel inspection device 10 is to be extracted from the reactor pressure vessel 1, the above-mentioned reverse procedure is performed.

"Effects of the Invention" As explained above, in the reactor pressure vessel inspection device according to the present invention, the rotary support table is vertically rotated to change the posture, so that narrow gaps between internal structures can be avoided. By sending the inspection equipment to the inspection target location such as the part, etc., and then using the traveling means and the elevating drive means in combination, it is possible to easily conduct a destruction inspection of the welded joint in the narrow part or the vicinity. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the reactor pressure vessel inspection device according to the present invention, FIG. 2 is a view taken along the line ■■ in FIG. 1, and FIG. A side view showing the relationship with the rotating support part, FIG. 4 is a view taken along the ■-IV line in FIG. 3,
Figure 5 shows ■-v in Figure 4 showing the rotating support stand and inspection equipment.
6 is a partially omitted plan view showing an example of a narrow part of a reactor pressure vessel in a boiling water reactor to which the reactor pressure vessel inspection device is applied; FIG. ■ in Figure 6
-■ A developed view of the inner surface of the reactor pressure vessel showing the narrow part and the weld line based on the line arrow view, and Figure 8 is a part showing the state of insertion of the reactor pressure vessel inspection device into the narrow part. FIG. 1...Reactor pressure vessel, 2...Reactor core,
3... Shroud, 3a... Guide groove, 4
... Core shroud (internal structure), 5...
...Jet pump, 10...Inspection device for reactor pressure vessel, 11...Support frame, 12...Elevating guide rod, 13...Elevating drive means, 14
...Moving frame, 15...Rotation drive means, 16.
... Rotating support stand, 17... Inspection equipment, 18...
... Traveling means, I9 ... Upper fixing means, 20
...Lower fixing means, 21...Scanning position sensor, 22...Underwater camera, 23...
Hanging tool, 24... Hanging stop part, 25... Hook part, 26... Insertion guide part, 27...
・Guide roller, 28... Rotation drive source, 29.
... Pole screw, 30 ... Mounting bracket, 31 ... Link mechanism, 32 ... Support stand, 33 ... Parallel cylinder, 34 ... ...Press spring, 35...Plate, 36... Side frame,
37... Guide rod rotation drive source, 39...
・Ball screw, 40-door block, W...Welding line (inspected area/support door, 38...fi). Applicant Ishikawajima Harima Heavy Industries Co., Ltd. Figure 3 Figure 4 Figure 8 JP-A-4-ES+5CS (6)

Claims (1)

[Claims] A support frame that is suspended from the upper edge of the internal structure of the reactor pressure vessel and whose lower end is inserted into the vicinity of the inspection point of the reactor pressure vessel; an elevating guide rod provided therein; a movable pedestal that is vertically movably supported by the elevating guide rod and raised and lowered by an elevating drive means; A rotating support provided with dimensional differences, an inspection device that is supported movably on the rotating support in the longitudinal direction and inspects the inner surface of the reactor pressure vessel, and an inspection device that is mounted on the rotating support and moves along the inspection point. 1. An inspection device for a nuclear reactor pressure vessel, comprising a traveling means for moving inspection equipment.