KR102212469B1 - Inspection device for steam generator - Google Patents

Abstract

An object of the present invention is to provide a steam generator inspection apparatus capable of inspecting the presence or absence of foreign substances in a gap in a heat transfer pipe bundle.
An embodiment of the present invention for solving the above problems is a flange installed in a handhole of a steam generator, a frame installed in the flange, a pulley installed in the frame, and the steam generator through the handhole. The guide rail installed along the outside of the inner heat transfer tube bundle, the moving part wound around the pulley and movable on the guide rail, the driving part for driving the pulley, and the moving part so as to be able to move forward and backward between the heat transfer tube bundle. It provides a steam generator inspection apparatus including a camera unit to be installed.

Description

Steam generator inspection device {INSPECTION DEVICE FOR STEAM GENERATOR}

The present invention relates to a steam generator inspection apparatus, and more particularly, to a steam generator inspection apparatus capable of inspecting the presence or absence of foreign substances in gaps in heat transfer pipe bundles.

In general, in a nuclear power plant, the steam generator generates the steam required to generate power from the steam turbine and generator.

Inside the steam generator, there are a number of heat transfer pipes in the form of bundles, and these heat transfer pipes perform heat exchange between the primary system tree containing radioactivity and the secondary system tree that runs the turbine, and It has a function of separating.

Looking at the steam generation process of the steam generator, the primary system water heated while passing through the reactor flows through the inside of the heat transfer pipe of the steam generator along the pipe, and the secondary system water supplied to the outside of the heat transfer pipe crosses the outside of the heat transfer pipe and crosses the pipe wall of the heat transfer pipe. The primary and secondary system water exchanges heat between them. Through this, the heat-exchanged primary system water is circulated back to the nuclear reactor along the closed circuit duct, and the secondary system water is converted into steam.

As described above, high-temperature and high-pressure radioactive water (primary system water) flows through the heat transfer pipe inside the steam generator, and non-radioactive water (secondary system water) flows outside, so if there is damage to the heat transfer pipe, it penetrates the inside of the heat transfer pipe. As radioactive water (primary system water) leaks to the outside, it is mixed with non-radioactive water (secondary system water), and as a result, non-radioactive water (secondary system water) is converted into steam, and the entire supplied area is radioactively contaminated. May result. Therefore, securing the soundness of the heat transfer tube is a top priority and important task in the operation of a nuclear power plant.

However, the secondary system water supplied to make steam in the conventional steam generator is supplied through filtration and chemical treatment, but it can be introduced into the steam generator along with foreign matter and sludge generated through various paths while circulating inside the pipe. In addition, impurities introduced or generated through various paths as described above become scale on the outer surface of the heat transfer tube, thereby reducing heat exchange power and causing damage to the heat transfer tube.

To this end, the removal of scale on the surface of the heat transfer tube is an essential means for ensuring the efficiency of the steam generator and the integrity of the heat transfer tube, and conventionally, the situation is manually checked using a small endoscope camera to check the surface condition of the heat transfer tube.

However, such equipment is used in such a way that the operator manually pushes the endoscope camera through the guide rail into the gap of the heat transfer tube, so it is cumbersome for the operator to manually push and take out the endoscope camera for confirmation, and it is difficult to find and check the desired location. There is a problem that there may be parts that have not been confirmed.

In addition, since the vicinity of the steam generator is a high radiation area, it is difficult for workers to perform efficient visual inspection or removal of foreign substances due to exposure to radiation.

Republic of Korea Patent Publication No. 10-2018-0080734 (published on July 13, 2018)

An object of the present invention is to provide a steam generator inspection apparatus capable of inspecting the presence or absence of foreign substances in gaps in a heat transfer pipe bundle.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. There will be.

An embodiment of the present invention for solving the above problems is a flange installed in a handhole of a steam generator, a frame installed in the flange, a pulley installed in the frame, and the steam generator through the handhole. The guide rail installed along the outside of the inner heat transfer tube bundle, the moving part wound around the pulley and movable on the guide rail, the driving part for driving the pulley, and the moving part so as to be able to move forward and backward between the heat transfer tube bundle. It provides a steam generator inspection apparatus including a camera unit to be installed.

According to an embodiment of the present invention, the guide rail may be installed along the outer side of the heat transfer tube bundle facing the dividing plate inside the steam generator.

According to an embodiment of the present invention, the guide rail may be formed in a straight line.

According to an embodiment of the present invention, it may further include a bracket installed on the flange to fix the guide rail.

According to an embodiment of the present invention, the moving part may include a moving body hingedly connected to a plurality of moving units, and a plurality of wheels coupled to the moving body and moving on the guide rail.

According to an embodiment of the present invention, the camera unit may be rotatably installed on the moving unit.

According to an embodiment of the present invention, the camera unit may include a wire, a probe coupled to the front of the wire, and a first camera installed toward the front of the probe.

According to an embodiment of the present invention, the camera unit may further include a second camera installed toward the side of the probe.

According to an embodiment of the present invention, each of the plurality of moving units includes a pair of plates arranged to face each other, each plate has two pinholes, and the plurality of moving units are adjacent plates One pinhole is disposed so as to overlap, and may be hinged to each other by a plurality of pins coupled to pass through the pinholes facing each other.

According to an embodiment of the present invention, a head portion coupled to any one of the plurality of pins may be further included, and the wire may penetrate the head portion.

According to an embodiment of the present invention, the pin and the head may be integrally formed.

According to an embodiment of the present invention, it may further include a pair of rollers installed on the moving part and passing through the wire.

According to an embodiment of the present invention, it is installed on the moving unit, it may further include a direction changing unit for changing the direction of the moving unit.

According to an embodiment of the present invention, the direction change unit may include a link coupled to the front of the moving unit and an actuator connected to the link.

According to an embodiment of the present invention, it is installed on the moving unit, may further include a position fixing unit for fixing the position of the moving unit.

According to an embodiment of the present invention, the position fixing part may be expandable and contracted in a direction closer to or away from the partition plate.

According to an embodiment of the present invention, the position fixing part may be formed of a rubber material.

According to an embodiment of the present invention, the height of the inspection device may be 30 mm or less.

According to the present invention, the moving unit can be moved forward and backward by the driving unit on the guide rail installed along the outside of the heat transfer tube bundle inside the steam generator, and the position of the moving unit can be easily fixed by the position fixing unit. After fixing the position of the moving part, the camera part can be moved forward and backward between the heat transfer tube bundles to easily inspect the presence or absence of foreign matter in the gap of the heat transfer tube bundle.

In addition, by moving the moving part along the outer side of the heat transfer pipe bundle facing the dividing plate inside the steam generator, not only can the inspection proceed on a straight portion, but also the curved portion can be inspected by changing the direction of the moving portion.

Accordingly, it is possible to efficiently perform visual inspection without the worker being exposed to the high radiation area.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a cross-sectional view showing a steam generator in which the steam generator inspection apparatus of the present invention is to be installed.
Figure 2 is a cross-sectional perspective view of a steam generator inspection apparatus according to an embodiment of the present invention as viewed from the outside of the steam generator installed in the steam generator.
3 is a side view as viewed from the inside of the steam generator in a state in which the steam generator inspection apparatus according to an embodiment of the present invention is installed in the steam generator.
Figure 4 is another side view of the steam generator inspection device of Figure 3;
Figure 5 is a perspective view of the steam generator inspection device of Figure 4;
Figure 6 is a perspective view showing the moving body separated from Figure 5;
7 is an enlarged view of another side view of a part of FIG. 4.
8 is a side view showing a state in which the moving part is moved forward in FIG. 3.
9 is a side view showing a state in which the moving part is moved forward in FIG. 8;

Hereinafter, a preferred embodiment of a steam generator inspection apparatus of the present invention will be described with reference to the accompanying drawings.

In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of users and operators, and the following examples do not limit the scope of the present invention, It is merely exemplary of the elements presented in the claims.

In order to clearly describe the present invention, parts irrelevant to the description have been omitted, and the same reference numerals are assigned to the same or similar components throughout the specification. Throughout the specification, when a certain part "includes" a certain component, it means that other components may be further provided without excluding other components unless otherwise stated.

The steam generator inspection apparatus according to an embodiment of the present invention is installed through the hand hole 12 of the steam generator 10, and as will be described in detail below, the moving part 500 is a heat transfer tube bundle 20 inside the steam generator. It moves through the guide rail 400 between the and the partition plate 30, and the camera unit 600 moves forward and backward between the heat transfer tube bundles 20 to inspect the presence or absence of foreign matter in the gap of the heat transfer tube bundle.

Hereinafter, looking at the steam generator inspection apparatus according to an embodiment of the present invention with reference to FIGS. 1 to 9, a flange 100, a frame 120, a pulley 200, a driving unit 300, and a guide It may include a rail 400, a moving unit 500 and a camera unit 600.

As shown in FIG. 2, a flange 100 may be installed in the hand hole 12 of the steam generator, and a frame 120 may be installed in the flange 100. The frame 120 may be fixedly installed in the hand hole 12 of the steam generator through the flange 100, and the frame 120 is installed outside the steam generator 10.

A pulley 200 is rotatably installed on the frame 120, and the pulley 200 may be rotated by a driving unit 300. Depending on the embodiment, the driving unit 300 may be a servo motor, and at this time, the driving unit 300 drives the pulley 200 by receiving a control signal to determine the position (moving distance) of the moving unit 500 Can be controlled.

A guide rail 400 is installed along the outside of the heat transfer tube bundle 20 inside the steam generator through the hand hole 12. In particular, as shown in FIG. 3, the guide rail 400 may be installed along the outer side of the heat transfer tube bundle 20 facing the dividing plate 30 inside the steam generator. Accordingly, the moving part 500 may be moved between the heat transfer tube bundle 20 and the partition plate 30 inside the steam generator through the guide rail 400.

In this embodiment, the guide rail 400 is formed in a straight line. That is, the guide rail 400 may be installed in a straight section corresponding to section A in the steam generator 10 shown in FIG. 1.

According to an embodiment, a bracket 140 installed on the flange 100 may be further included to fix the guide rail 400.

The moving part 500 is wound around the pulley 200 and is movable on the guide rail 400. When the pulley 200 is rotated by the driving unit 300 to release the moving unit 500, the moving unit 500 advances in the inner direction of the steam generator, and when the moving unit 500 is wound, the moving unit 500 moves backward in the outer direction of the steam generator.

Specifically, referring to FIGS. 3 to 6, the moving unit 500 is coupled to a moving body 520 and the moving body 520 to which a plurality of moving units are hingedly connected to each other, and the guide rail 400 It may include a plurality of wheels 540 moving on the top. In this way, the moving body 520 is composed of a plurality of moving units that are hinged to each other so that the direction change is possible, so that the moving unit can be moved to a curved section as well as a straight section. That is, the moving unit 500 may move from the steam generator 10 shown in FIG. 1 to the section B as well as section A where the guide rail 400 is installed. The plurality of wheels 540 may be disposed on both sides of the moving body 520 in a plurality of pairs along the direction of the guide rail 400.

In this embodiment, each of the plurality of moving units includes a pair of plates 522 arranged to face each other, and each plate 522 is provided with two pinholes, and the plurality of moving units are adjacent plates. The pinholes 522 are disposed so as to overlap each other, and may be hingedly connected to each other by a plurality of pins 524 coupled to pass through the pinholes facing each other.

More specifically, in this embodiment, the moving body 520 is formed as a roller chain. It goes without saying that the moving body 520 may further include a roller, a bush, etc. in addition to the plate 522 and the pin 524.

In this case, an attachment 526 is provided on a pair of plates disposed on the outside of the plurality of moving units, and the plurality of wheels 540 may be coupled to the moving body 520 through the attachment 526. .

The moving part 500 is provided with a camera part 600 so as to be able to move forward and backward between the heat transfer tube bundles 20.

Specifically, as shown in FIG. 7, the camera unit 600 includes a wire 610, a probe 620 coupled to the front of the wire 610, and the probe 620 installed toward the front. It includes a first camera 630.

The wire 610 is wound around a separate pulley disposed outside the steam generator 10 and wound or unwound according to the rotation of the pulley, so that the probe 620 can be moved forward and backward. It goes without saying that the pulley on which the wire 610 is wound may also be installed on the frame 120 according to an embodiment.

A pair of roller units 650 may be installed in front of the moving unit 500, and in detail, in this embodiment, the pair of roller units 650 are in the foremost moving unit of the moving body 520 It is coupled through an attachment 526. As the wire 610 penetrates between the pair of roller parts 650 and the pair of roller parts 650 rotates, the wire 610 may smoothly move forward and backward.

A first camera 630 is installed on the probe 620 toward the front, and as the probe 620 moves forward and backward through the steam pipe bundle 20, the first camera 630 By photographing the space, the operator can visually inspect the presence of foreign substances between the steam pipe bundles 20 and whether there is damage.

Moreover, according to an embodiment, the camera unit 600 may be rotatably installed on the moving unit 500. A head portion 660 coupled to any one of the plurality of pins 524 may be further included, and the wire 610 may be disposed to pass through the head portion 660. In this embodiment, the pin 524 and the head portion 660 are integrally formed.

Accordingly, the direction in which the wire 610 enters between the steam pipe bundles 20 may be adjusted. That is, the wire 610 may not only enter in a direction perpendicular to the longitudinal direction of the moving body 520, but may also enter at a different angle as shown in FIG. 9.

In addition, according to an embodiment, the camera unit 600 may further include a second camera 640 installed toward the side of the probe 620.

Through this, when it is difficult for the camera unit 600 to enter the line between the steam pipe bundles 20 in which a tie rod is arranged inside the steam generator 10, the second camera is installed toward the side by entering the proximity line. Through 640, the line where the tie rod is placed can be inspected.

According to an embodiment, it is installed on the moving part 500 and may further include a position fixing part 700 for fixing the position of the moving part 500. The position fixing part 700 may be coupled to the moving body 520 through an attachment 526.

The position fixing part 700 can be expanded or contracted in a direction closer to or away from the partition plate 30, and in this embodiment, the position fixing part 700 is formed of a plurality of air tubes. The position fixing part 700 is preferably formed of a rubber material to protect the partition plate 30.

In this way, after moving the moving unit 500, the position of the moving unit is fixed through the position fixing unit 700, and the camera unit 600 enters between the steam pipe bundles 20, so that the inspection can be performed stably.

In addition, according to an embodiment, it is installed in the moving unit 500 and may further include a direction changing unit 800 for changing the direction of the moving unit 500.

The direction change unit 800 includes a link 820 coupled to the front of the moving unit 500 and an actuator 840 coupled to the link 820. Specifically, in the present embodiment, the link 820 is coupled to the pair of roller units 650, but is not limited thereto, and may be directly connected to the moving body 520. The actuator 840 may be coupled to the moving body 520, and the link 820 is connected to the output shaft 842 of the actuator 840.

Therefore, when the actuator 840 does not protrude the output shaft 842, the front of the moving part 500 is maintained straight by the link 820, but as shown in FIG. 8, the actuator 840 When the output shaft 842 is protruded, the link 820 is bent from the output shaft and the front direction of the moving part 500 can be changed. Accordingly, when the moving unit 500 passes from section A to section B, the forward direction is bent and can be easily moved from a straight section to a curved section.

After the moving part 500 enters the curved section, that is, the B section, as shown in FIG. 9, the actuator 840 is driven so that the output shaft 842 does not protrude again, and the moving part 500 It can maintain the straightness ahead. Even in a curved section, the position of the moving part 500 may be fixed by the position fixing part 700.

When the moving part 500 moves in section A, the camera part 600 moves forward and backward in a direction perpendicular to the direction in which the moving part 500 moves, that is, the x direction shown in FIG. (20) Inspect the gap.

At this time, even when the moving part 500 moves in section B, the head part 660 rotates to maintain the inspection direction of the camera part 600. That is, as shown in FIG. 9, the entry direction of the wire 610 may be adjusted so that the head portion 660 rotates so that the wire 610 may enter the x direction.

The height of the inspection apparatus may be limited so that the inspection apparatus of the present invention is inserted between the split plate 30 and the steam pipe bundle 20 of the steam generator to allow smooth movement and inspection. In particular, it is preferable that the height from the guide rail 400 to the highest component except for the position fixing part 700 is within 30mm.

In the present embodiment, the height from the guide rail 400 to the direction change part 800 may be formed within 30 mm. However, the present invention is not limited thereto, and when the pair of roller units 650 is formed higher than the direction change unit 800, the height from the guide rail 400 to the pair of roller units 650 is It may be formed within 30mm.

At this time, the height from the guide rail 400 to the position fixing part 700 is smaller than the distance between the dividing plate 30 of the steam generator and the steam pipe bundle 20 before the position fixing part 700 is increased, As it increases, the distance between the split plate 30 of the steam generator and the steam pipe bundle 20 may be equal to or greater.

Moreover, it may further include a control unit for controlling the inspection apparatus of the present invention. When the driving unit 300 is a servo motor, the controller may control the position (moving distance) of the moving unit 500 by transmitting a control signal thereto and driving the pulley 200. In addition, the controller may receive, store, and process an image captured by the camera unit 600.

Hereinafter, a method of inspecting between bundles of heat transfer pipes of a steam generator using the inspection apparatus of the present invention will be briefly described.

First, the inspection device of the present invention is installed through the hand hole 12 of the steam generator, and the camera unit 600 is transferred between the heat transfer tube bundles 20 while moving the moving unit 500 by driving the pulley 200. , It is possible to inspect between the heat transfer pipe bundles 20 by reversing.

Specifically, in the steam generator 10 shown in FIG. 1, after the moving part 500 enters the inside of the steam generator through the hand hole 12, the position is located for each line between the heat transfer pipe bundles 20. The position is fixed by the governmental part 700, and after fixing, the camera part 600, more precisely, the wire 610 advances between the steam pipe bundles 20 to perform the inspection. When the inspection of one line is completed, the wire 610 moves back to the original position and then the moving unit 500 moves to the next line.

Once the inspection device of the present invention is installed in the hand hole 12 of the steam generator, the area corresponding to 1/4 of the steam generator can be inspected. That is, since the hand holes 12 of the steam generator are formed to face each other on both sides, an inspection device is installed in one hand hole to perform an inspection of a quarter area, and then an inspection device is installed in the opposite hand hole to be /4 area can be inspected. Then, after rotating the steam generator by 180°, the same inspection can be conducted, and a total of four inspections can be conducted for one steam generator.

According to the present invention, the moving unit 500 can be moved forward and backward by the driving unit 300 on the guide rail 400 installed along the outer side of the heat transfer tube bundle 20 inside the steam generator, and the position fixing unit 700 ), the position of the moving part can be easily fixed. After the position of the moving part 500 is fixed, the camera part 600 moves forward and backward between the heat transfer tube bundles, so that the presence or absence of foreign matter in the gap of the heat transfer tube bundle 20 can be easily inspected.

In addition, the moving part 500 moves along the outer side of the heat transfer pipe bundle 20 facing the dividing plate 30 inside the steam generator, so that the inspection can be performed on a straight part, as well as the direction of the moving part 500 It is also possible to inspect the curved part.

Accordingly, it is possible to efficiently perform visual inspection without the worker being exposed to the high radiation area.

The present invention is not limited to the specific embodiments and description described above, and any person with ordinary knowledge in the technical field to which the present invention pertains without departing from the gist of the present invention claimed in the claims can implement various modifications And, such modifications are within the scope of protection of the present invention.

10: steam generator 12: hand hole
20: heat transfer tube bundle 30: partition plate
100: flange 120: frame
140: bracket 200: pulley
300: drive unit 400: guide rail
500: moving part 520: moving body
522: plate 524: pin
526: attachment 540: multiple wheels
600: camera unit 610: wire
620: probe 630: first camera
640: second camera 650: a pair of roller units
660: head part 700: position fixing unit
800: direction switching unit 820: link
840: actuator 842: output shaft

Claims (19)

A flange installed in the handhole of the steam generator;
A frame installed on the flange;
A pulley installed on the frame;
A guide rail installed along the outside of the heat transfer tube bundle inside the steam generator through the hand hole;
A moving part wound around the pulley and movable on the guide rail;
A driving unit for driving the pulley; And
Includes; a camera installed in the moving part to enable forward and backward between the heat transfer tube bundle,
The camera unit is rotatably installed on the moving unit, the steam generator inspection device. The method of claim 1,
The guide rail is installed along the outside of the heat transfer pipe bundle facing the dividing plate inside the steam generator. The method of claim 2,
The guide rail is made of a straight line, steam generator inspection device. The method of claim 2,
A bracket installed on the flange to fix the guide rail;
The steam generator inspection apparatus further comprising a. The method of claim 2,
The moving part,
A moving body in which a plurality of moving units are hingedly connected to each other; And
A plurality of wheels coupled to the moving body and moving on the guide rail;
Containing, steam generator inspection device. A flange installed in the handhole of the steam generator;
A frame installed on the flange;
A pulley installed on the frame;
A guide rail installed along the outside of the heat transfer tube bundle inside the steam generator through the hand hole;
A moving part wound around the pulley and movable on the guide rail;
A driving unit for driving the pulley;
A camera unit installed on the moving unit to enable forward and backward movement between the heat transfer tube bundles; And
Including, a steam generator inspection device installed on the moving part, for changing the direction of the moving part. The method of claim 5,
The camera unit,
wire;
A probe coupled to the front of the wire; And
A first camera installed toward the front of the probe;
Containing, steam generator inspection device. The method of claim 7,
The camera unit,
A second camera installed toward the side of the probe;
Further comprising a steam generator inspection device. The method of claim 7,
Each of the plurality of moving units includes a pair of plates arranged to face each other, and each plate has two pinholes,
The plurality of moving units are disposed so that one pinhole overlaps adjacent plates, and are hingedly connected to each other by a plurality of pins coupled to pass through the pinholes facing each other. The method of claim 9,
Further comprising a; head portion coupled to any one of the plurality of pins,
The wire is characterized in that through the head portion, steam generator inspection device. The method of claim 10,
The pin and the head portion, characterized in that formed integrally, steam generator inspection apparatus. The method of claim 7,
A pair of roller parts installed on the moving part and through which the wire passes;
Further comprising a steam generator inspection device. The method of claim 5,
A direction changing unit installed on the moving unit and configured to change the direction of the moving unit;
Further comprising a steam generator inspection device. The method of claim 13,
The direction change unit,
A link coupled to the front of the moving part; And
An actuator connected to the link;
Containing, steam generator inspection device. The method of claim 5,
A position fixing unit installed on the moving unit and configured to fix the position of the moving unit;
Further comprising a steam generator inspection device. The method of claim 15,
The location fixing unit is expandable and contractible in a direction closer to or away from the partition plate, a steam generator inspection device. The method of claim 16,
The position fixing part is formed of a rubber (rubber) material, steam generator inspection device. The method of claim 13,
A steam generator inspection apparatus, characterized in that the height of the inspection apparatus is 30 mm or less. A flange installed in the handhole of the steam generator;
A frame installed on the flange;
A pulley installed on the frame;
A guide rail installed along the outside of the heat transfer tube bundle inside the steam generator through the hand hole;
A moving part wound around the pulley and movable on the guide rail;
A driving unit for driving the pulley;
A camera unit installed on the moving unit to enable forward and backward movement between the heat transfer tube bundles; And
And a position fixing unit installed on the moving unit and configured to fix the position of the moving unit.

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