JPH0660952B2 - Inspection and repair equipment for steam generator tubes in nuclear power plants - Google Patents

Description

The present invention relates to an apparatus for inspecting and repairing a tube of a steam generator of a nuclear power plant.

[Conventional technology]

An inspection and repair device for a tube (passage) of a steam generator of a nuclear power plant is disclosed in, for example, European Patent Application Publication Nos. 0008386 and 0138583. The device for inspection and repair can be inserted into the inside of the steam generator through a manhole provided in the outer case of the steam generator and attached to the tube sheet of the steam generator during inspection and repair.

The device for inspection and repair is a robot consisting of an arm assembly that operates while attached to the tubesheet of the steam generator. The device includes an upper plate and a lower plate connected by a guide bar, a carriage is movable up and down along the guide bar, and a shoulder portion having an upper arm rotatably connected to the carriage. An elbow having a lower arm rotatably connected,
An arm assembly consisting of a wrist to which inspection and repair tools can be connected is connected. The wrist can be moved in a three-dimensional space under remote control for inspection and repair, and can be in a position facing away from the carriage.

In order to secure the device for inspection and repair to the tubesheet of the steam generator, the upper plate of the device is equipped with span fingers which are intended to be fixed in the two passages of the tubesheet. ing.

[Problems to be Solved by the Invention]

Inspections and repairs must be performed on all passages in the tubesheet. With the device in which the span fingers are fixed in the passage of the tube sheet, passages other than those in which the span fingers are engaged can be inspected and repaired, but inspection and repair of passages in which the span fingers are engaged are not possible. There was a problem that it could not be implemented unless the span finger moved from that passage to another passage. The movement of the span finger means the movement of the entire device, and it takes time to move the entire device in the atmosphere of radioactivity.
This is a costly job. The above-mentioned European Patent Application Publication No. 0008386 discloses a device which enables such movement, but the device requires a large support plate having a large number of holes to fit the passages of the tube sheet, It was complicated and difficult to use. The present invention aims to solve these problems.

[Means for Solving the Problems]

An apparatus for inspecting and repairing tubes of a steam generator of a nuclear power plant according to the present invention is a device that can be attached to a tube sheet of a steam generator,
A shoulder portion having an upper plate and a lower plate connected by a guide bar, the carriage being capable of moving up and down along the guide bar, and a shoulder portion having an upper arm rotatably connected to the carriage; An arm assembly including an elbow portion having a freely connected lower arm and a wrist portion to which an inspection and repair tool can be connected can be connected, and the wrist portion can face the carriage away from the carriage. The arm assembly includes drive means for remotely operating the inspection and repair tools, and the upper plate is connected to the wrist in an inspection and repair device that can be secured by span fingers in the two passages of the tubesheet. A yoke, which can receive the fixing member of the auxiliary tool, is attached to the shoulder, and the auxiliary tool can be fixed in another passage of the tube sheet. It comprises two additional span fingers, is characterized in that it has to be able to move the span fingers of the upper plate to another set of passages of the tube sheet.

[Action effect]

According to the above arrangement, an auxiliary tool with two additional span fingers which can be fixed in the other passages of the tubesheet is usually supported on a yoke provided on the shoulder of the carriage of the device. When the span finger engaged in the passage of the tube sheet is moved to another passage, the auxiliary tool is connected to the wrist portion of the device, and the wrist portion is operated so that the additional span finger provided in the auxiliary tool is attached to the tube. Insert into another passage in the seat and secure it there. In this state, the span finger of the main body can be pulled out from the passage of the tube sheet and fixed to another passage of the tube sheet. Therefore, the auxiliary tool can be returned to the yoke, and an inspection or repair tool can be attached to the wrist for inspection and repair. Thus, according to the present invention, the tube of the steam generator of the nuclear power plant can be efficiently inspected and repaired with a relatively simple structure.

The invention is further explained below on the basis of the drawings, which show by way of example one embodiment of the device of the invention.

〔Example〕

The device shown in FIG. 1 comprises an upper plate 1 and a lower plate 2, which are connected by two guide bars 3 and 4. The carriage 5 can move along the guide bars 3 and 4. This movement is brought about by the carriage 5 comprising a threaded sleeve (not shown) mounted on a spindle 6 extending therethrough, which spindle 6 is rotationally driven by drive means 7.

The upper plate 1 comprises two span fingers 8 which can be fixed in passages 9 in the tubesheet 10 of the steam generator. The term span fingers means a fixing means which can be inserted when they are of small diameter and which can be expanded after insertion so that a firm fixation is obtained between these two parts. To be understood.

The bottom plate 2 has two vertically adjustable support legs 11 and 12
And with this help the device is a span finger 8
Can be extended for insertion into the passage 9.

The carriage 5 comprises a receiving dovetail portion 13 designed in a known manner so as to receive the insert dovetail portion 14 of the shoulder 15 of the arm assembly 16, which arm assembly
16 is an upper arm 15 ', an elbow 17 and a lower arm 1
7'and a wrist portion 18 are provided. Here, the upper arm 15 ′ and the lower arm 17 ′ are not expressed according to the vertical relationship in the drawings, but the shoulder portion 15, the elbow portion 17, and the wrist portion.
It was used in correspondence with the term 18 (ie, the upper arm 15 'corresponds to the upper arm between the shoulder and elbow in humans). The drive means 19 allow the upper arm 15 'to rotate about a vertical shaft relative to the shoulder 15,
Also, between the lower arm 17 'and the upper arm 15' and the wrist 18
And a lower arm 17 ', respectively, likewise rotatable about a vertical shaft. In this way, the wrist portion 18 can accurately reach all points in the three-dimensional space together with the carriage 5.

Parts 1 to 13 are inserted into the inside of the steam generator through a manhole provided in the outer case of the steam generator, and the upper plate 1 is pulled up to the height of the tube sheet 10 of the steam generator, and two span fingers 8 are attached. Has tube sheet 10
After being fixed in their respective passages 9, the parts 14 to 19 are attached to the carriage 5 with the aid of the dovetail joints 13/14. A known release lever 20 is provided to release the joint again upon removal of the device.

At its end, the wrist 18 comprises a receiving dovetail portion 21 arranged in a known manner, from which tools for inspection or repair can be hung.

With the help of the cable 22, the camera and the monitoring device (not shown), this whole device, which can be considered as a robot, can be controlled remotely.

According to the invention, the receiving dovetail part 21 of the wrist 18 is
Inserting the auxiliary tool 23 shown in FIGS.
It can also be used to position 24.

The auxiliary tool 23 comprises two guide bars 27, 28 connected by end partitions 25 and 26. A screw spindle 29 is arranged between these bars, this spindle 29 being the drive means.
It can be driven by 30 and thereby with the aid of a threaded sleeve fixedly mounted in a table 31, this table can be moved back and forth along the guide bar. The cables needed to drive the carriage are connected to a connector 32 and then extend through a cable gutter 33 to a drive means 30.

The insert dovetail portion 24 of the auxiliary tool 23 is attached to the outer surface of the vertical portion of the corner member 34. The horizontal portion of the angle member 34 is attached to the underside of the table 31 and the fixing member 35 is provided below the horizontal portion. The fixing member 35 is as shown by the dotted line in FIG. Yoke mounted on shoulder 15 if the remote control is correct
You can enter 36 naturally. The fixing member 35 is a yoke
Once placed in 36, the securing member can then be expanded so that a rigid connection to the yoke is formed.

The additional span fingers 37 and 38 are the end bulkheads of the auxiliary tool 23.
Mounted on 25 and 26, so that the robot is temporarily suspended from these additional span fingers 37 and 38, after which the span fingers 8 of the upper plate 1 are transferred to another set of passages 9 of the tubesheet 10. Can be programmed to. With the aid of the invention, the robot can thus be quickly transferred to another position with respect to the tube sheet, so that the tube on which the upper plate span finger 8 is located can also be inspected or repaired.

It goes without saying that during these operations many precautions must be taken to eliminate radioactive contamination of the environment and personnel. One of the precautions is to mount a sensor 39 on top of the end bulkheads 25 and 26, which assess whether the auxiliary tool 23 has reached its target.

The end bulkheads 25 and 26 are replaceable so that the additional span fingers 37 and 38 have the correct pitch and diameter for the passage of the tubesheet 10.

Other embodiments of what are shown in the drawings are also within the scope of the following claims.

[Brief description of drawings]

FIG. 1 is a perspective view of an apparatus for inspection and repair without auxiliary tools, and FIGS. 2 to 4 are a rear view, a plan view and a side view of an auxiliary tool of the present invention. DESCRIPTION OF SYMBOLS 1 ... Upper plate, 2 ... Lower plate, 3, 4 ... Guide bar, 5 ... Carriage, 6 ... Spindle, 7 ... Driving means, 8 ... Span fingers, 9 ... Passage, 10 ... Tube sheet, 15 ... Shoulder, 18 … Wrist, 23… Auxiliary tool, 25, 26… End partition, 27, 28… Guide bar, 31… Table, 35… Fixing member, 37, 38… Additional span finger, 39… Sensor.

Claims (4)

[Claims] 1. A device which can be mounted on a tube sheet (10) of a steam generator for inspecting and repairing tubes of the steam generator of a nuclear power plant, which is connected by guide bars (3, 4). Upper plate (1)
And a lower plate (2), the carriage (5) can move up and down along the guide bar,
A shoulder (15) having an upper arm (15 ') rotatably connected, an elbow (17) having a lower arm (17') rotatably connected, and an inspection or repair tool are connected An arm assembly (16) comprising a wrist part (18) which can be engaged with the wrist part so that the wrist part can face the carriage away from the carriage, the carriage and the arm assembly for remotely operating the inspection or repair tool. Of the auxiliary plate connected to the wrist (18) in an inspection and repair device which is equipped with a drive means of the upper plate and can be fixed in the two passages (9) of the tube sheet (10) by the span fingers (8). A yoke (36) capable of receiving the fixing member (35) of the tool (23)
Is attached to the shoulder (15), and the auxiliary tool is provided with two additional span fingers (37, 38) that can be fixed in the other passages of the tube sheet (10), and the span finger of the upper plate (1) The inspection and repair device characterized in that (8) can be moved to another passage of the tube sheet. 2. An auxiliary tool (23) is composed of two guide bars (27, 28) connected by end partition walls (25, 26), and is connected to a fixing member (35) along the guide bars. The table (31) can be moved and additional span fingers (3
Inspection and repair device according to claim 1, characterized in that 7,38) are mounted on the end bulkheads (26,26). 3. The end bulkheads (25,26) of the auxiliary tool (23) are replaceable, whereby additional span fingers (37,38)
2. The pitch distance of the tube sheet is adapted to the tube pitch of the tube sheet (10).
Or the inspection and repair device described in 2. 4. Inspection and repair device according to one of claims 1 to 3, characterized in that the proximity sensor (39) is mounted on the top of the end partition (25, 26).