JP2023009419A - Steam generator inspection device, and steam generator inspection method - Google Patents

Abstract

To provide a steam generator inspection device that can efficiently inspect an outer surface of a heat transfer pipe a steam generator has over a wide range.SOLUTION: An inspection device 100 of a steam generator inspects the steam generator that includes a heat transfer pipe 32 extending in a vertical direction Z inside a trunk 2, and a pipe supporting plate 33 having a flow slot 36, and supporting the heat transfer pipe relative to the trunk. The inspection device comprises: an inspection cable 110 that is inserted into the inside part of the trunk from a hand hole 24 located in a lower part of the trunk, and has, at a tip, an inspection probe 111 for inspecting an outer surface of the heat transfer pipe; a holding mechanism 120 that movably holds the inspection cable in a longitudinal direction of the inspection cable, is movable in the vertical direction with the heat transfer pipe as a guide, and can pass the flow slot of the pipe supporting plate; and an elevation mechanism 130 that causes the holding guide mechanism to move in the vertical direction.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a steam generator inspection device and a steam generator inspection method.

For example, in a nuclear power plant using a pressurized water reactor (PWR), a steam generator is used to generate steam for driving a turbine connected to a generator. In this type of steam generator, the primary cooling water supplied from the nuclear reactor flows inside the heat transfer tubes accommodated inside the body, and the secondary cooling water flows outside the heat transfer tubes. In the heat transfer tubes, the high-temperature primary cooling water heats the secondary cooling water, thereby generating steam to be supplied to the turbine.

One of the inspection items of a nuclear power plant is quality inspection of heat transfer tubes of steam generators. For example, in Patent Document 1, although not intended for steam generators used in nuclear power plants, the posture of an inspection device inserted inside a tubular inspection object is stabilized by fixing with a balloon. Thus, a technique for improving inspection quality is disclosed.

JP-A-10-239593

One of the inspection items for steam generators is an observation inspection of the outer surface of heat transfer tubes. For example, in the steam generator described above, foreign matter may be mixed in the secondary cooling water, and the foreign matter may accumulate around the heat transfer tubes, or the outer surface may be damaged due to collision of the foreign matter with the heat transfer tubes. Sometimes. In order to detect such abnormalities, conventionally, an inspection probe (for example, an imaging device such as a CCD camera capable of imaging the outer surface) is externally inserted through a hand hole provided on the side surface of the body of the steam generator. ) to inspect the outer surface of the heat transfer tube placed inside the body. However, since the interior of the body is partitioned by a plurality of tube support plates for supporting the heat transfer tubes, the accessible range of the inspection probe inserted from the handhole is limited. In recent years, quality requirements for steam generators have been increasing, and it is required to efficiently inspect the outer surface of heat transfer tubes over a wider range.

The present disclosure has been made to solve the above problems, and includes a steam generator inspection device capable of efficiently inspecting the outer surface of a heat transfer tube of a steam generator over a wide range, and a steam generator inspection. The purpose is to provide a method.

A steam generator inspection apparatus according to the present disclosure includes a vertically extending heat transfer tube inside a vertically extending body, and supporting the heat transfer tube with respect to the body so that heat flows through the interior of the body. and a tube support plate having a flow slot through which a medium can pass in a vertical direction. and an inspection cable having an inspection probe for inspecting the outer surface of the heat transfer tube, and the inspection cable is held so as to be movable in the longitudinal direction, and can be moved vertically using the heat transfer tube as a guide. and a holding guide mechanism that can pass through the flow slot of the tube support plate, and an elevating mechanism that vertically moves the holding guide mechanism.

A method for inspecting a steam generator according to the present disclosure is a method for inspecting a steam generator using the inspection device, comprising: a guiding step of guiding the holding guide mechanism to a predetermined region in the vertical direction by the lifting mechanism; and an inspection step of inspecting the outer surface of the heat transfer tube with the inspection probe in a predetermined area.

A steam generator inspection apparatus according to the present disclosure includes a vertically extending heat transfer tube inside a vertically extending body, and supporting the heat transfer tube with respect to the body so that heat flows through the interior of the body. and a tube support plate having a flow slot through which a medium can pass in a vertical direction. an inspection cable having an inspection probe for inspecting the outer surface of the heat transfer tube, a first guide portion extending toward the inside of the body from a hand hole located at the bottom of the body, and the second It has a second guide part that curves and extends from the tip of one guide part to the first guide part, and guides the inspection cable along the first guide part and the second guide part in order. and a guide member.

A method for inspecting a steam generator according to the present disclosure is a method for inspecting a steam generator using the inspection device, wherein the first guide part is directed from a hand hole located at the bottom of the body toward the inside of the body. an installation step of installing the guide member so that the guide member extends along the length of the body and the tip of the second guide portion is arranged at a predetermined position inside the body; and the inspection cable guided by the guide member. and an inspection step of inspecting the outer surface of the heat transfer tube with the inspection probe by advancing from the tip of the second guide portion.

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a steam generator inspection apparatus and a steam generator inspection method capable of efficiently inspecting the outer surface of a heat transfer tube of a steam generator over a wide range.

1 is a schematic configuration diagram showing a steam generator according to a first embodiment of the present disclosure; FIG. FIG. 2 is a plan sectional view showing a tube support plate and heat transfer tubes of the steam generator of FIG. 1; FIG. 2 is a perspective view showing a main part of the steam generator of FIG. 1 and an inspection device according to the first embodiment of the present disclosure; FIG. 4 is an enlarged perspective view showing a holding guide mechanism and an inspection cable of FIG. 3; FIG. 5 is an enlarged view of the holding guide mechanism of FIGS. 3 and 4 as seen from the left-right direction X; FIG. 5 is an enlarged view of main parts of the holding guide mechanism of FIGS. Figure 5 shows the process of the holding guide mechanism of Figures 3 and 4 passing through the flow slots in the tube support plate; FIG. 4 is a cross-sectional plan view showing a first example of the relative position between the flow slot of the tube support plate and the holding guide mechanism and the movement range of the holding part corresponding to the relative position in the inspection device of the first embodiment. FIG. 7 is a cross-sectional plan view showing a second example of the relative position between the flow slot of the tube support plate and the holding guide mechanism and the movement range of the holding part corresponding to the relative position in the inspection device of the first embodiment. FIG. 2 is a plan cross-sectional view showing a main part of the steam generator of FIG. 1 , a guide member of a first example of an inspection device according to a second embodiment of the present disclosure, and a first inspection example of an inspection method using the guide member; FIG. 11 is a side cross-sectional view showing a second inspection example of the inspection method using the principal part of the steam generator of FIG. 1 and the guide member of the first example of FIG. 10 ; FIG. 2 is a plan cross-sectional view showing a main part of the steam generator of FIG. 1, a guide member of a second example of an inspection device according to a second embodiment of the present disclosure, and an inspection method using the same; FIG. 3 is a side cross-sectional view showing a main part of the steam generator of FIG. 1 , a guide member of a third example of an inspection device according to a second embodiment of the present disclosure, and a first inspection example of an inspection method using the guide member; 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13; FIG. FIG. 15 is a side cross-sectional view showing a second inspection example of the inspection method using the principal part of the steam generator of FIG. 1 and the guide member of the third example of FIGS. 13 and 14; FIG. 16 is a cross-sectional plan view of FIG. 15 viewed from the XVI direction; 17 is a cross-sectional view taken along line XVII-XVII of FIG. 16; FIG. FIG. 4 is a side cross-sectional view showing a main part of the steam generator of FIG. 1, a guide member of a fourth example of the inspection device according to the second embodiment of the present disclosure, and an inspection method using the same; FIG. 19 is a plan cross-sectional view of FIG. 18 viewed from the XIX direction; 20 is a cross-sectional view taken along line XX-XX of FIG. 19; FIG. FIG. 3 is a side cross-sectional view showing a first inspection example of an inspection apparatus and an inspection method using the same according to a third embodiment of the present disclosure; FIG. 22 is a cross-sectional view taken along line XXII-XXII of FIG. 21; 23 is a side cross-sectional view showing a second inspection example of the inspection method using the main part of the steam generator of FIG. 1 and the inspection apparatus of FIGS. 21 and 22; FIG. FIG. 24 is a cross-sectional view taken along line XXIV-XXIV of FIG. 23; 2 is a perspective view showing a main part of the steam generator of FIG. 1 and an inspection device according to a fourth embodiment of the present disclosure; FIG. 26 is a side cross-sectional view showing an enlarged vicinity of the tip portion of the guide member of FIG. 25; FIG. 27 is a transparent perspective view showing the inside of the tip portion of the cable container of FIGS. 25 and 26; FIG.

<Embodiment>
(Steam generator configuration)
First, a steam generator to be inspected by the inspection apparatus according to this embodiment will be described.
A steam generator 1 of this embodiment shown in FIG. 1 is applied to, for example, a nuclear power plant. In the steam generator 1, heat is exchanged between the high-temperature primary cooling water heated in the nuclear reactor (not shown) and the secondary cooling water (medium) supplied from the outside. Steam is generated from the secondary cooling water. Electric power can be generated by sending the generated steam from the steam generator 1 to a turbine generator (not shown).
As shown in FIG. 1 , the steam generator 1 includes a body section 2 and a heat exchange section 3 . The steam generator 1 further includes a water supply unit 4 , a steam separator 5 , a water chamber mirror 6 and a moisture separator 7 .

(torso)
The trunk portion 2 is formed in a cylindrical shape extending in the vertical direction. The barrel 2 has a lower barrel 2a forming a lower half, an upper barrel 2b forming an upper half, and an upper mirror 2d provided at the upper end of the upper barrel 2b. A steam outlet 22 is formed in the upper mirror 2d. A pipe (not shown) for sending steam discharged from the body 2 to the turbine generator is connected to the steam discharge port 22 .

(direction definition)
In this embodiment, the direction in which the body 2 extends is called the up-down direction Z. As shown in FIG. A direction orthogonal to the up-down direction Z is called a left-right direction X. As shown in FIG. A direction orthogonal to the up-down direction Z and the left-right direction X is called a front-back direction Y (see FIGS. 2, 3, etc.). The front-rear direction Y in FIG. 1 is a direction perpendicular to the plane of the paper.

A tube sheet 8 is arranged at the lower end of the lower shell 2a. The tube sheet 8 closes the opening at the lower end of the lower shell 2a. The tube sheet 8 is formed with a plurality of tube holes 8a penetrating in the vertical direction Z. As shown in FIG.

Hand holes 23, 24 and 25 are provided on the side surface of the lower trunk 2a. The hand holes 23, 24, 25 are formed so as to pass through the wall of the lower trunk 2a, and are sealed by a sealing member 26 during normal times (when not inspected). In an abnormal state (inspection), the hand holes 23, 24, and 25 are opened by removing the sealing member 26. As shown in FIG. When the handholes 23, 24, 25 are open, the heat transfer tube group 32A of the heat exchange section 3, which will be described later, is arranged inside the lower shell 2a through the handholes 23, 24, 25 from the outside of the lower shell 2a. be accessible. The position and number of hand holes 23, 24, 25 provided in the barrel 2 may vary depending on the plant.

The hand holes 23, 24, and 25 of this embodiment include a first lower hand hole 23 and a second lower hand hole 24 positioned below the lower barrel 2a, and an upper hand hole 25 positioned above the lower barrel 2a. There is. The first lower handhole 23 is located below the second lower handhole 24 . The first lower hand hole 23, the second lower hand hole 24, and the upper hand hole 25 are provided two by two at positions facing each other in the radial direction (lateral direction X) of the cylindrical lower body 2a. there is That is, the first lower hand hole 23, the second lower hand hole 24, and the upper hand hole 25 are arranged two by two at positions spaced apart by approximately 180 degrees in the circumferential direction of the lower body 2a when viewed from the vertical direction Z. are placed.

(Heat exchange part)
The heat exchange part 3 is provided inside the lower shell 2a (the lower part in the shell part 2), and heat-exchanges high-temperature primary cooling water with secondary cooling water to cool it. The heat exchange section 3 includes a tube bundle outer cylinder 31 (wrapper tube), a heat transfer tube bundle 32A, a tube support plate 33, and a flow distribution plate 34 (FDB).
The tube bundle outer cylinder 31 is formed in a cylindrical shape extending in the up-down direction Z. As shown in FIG. The tube bundle outer cylinder 31 is arranged at a predetermined distance from the inner peripheral surface of the lower shell 2a. The lower end portion of the tube bundle outer cylinder 31 is located near the tube sheet 8 arranged at the lower end portion of the lower shell 2a. The upper end of the tube bundle outer cylinder 31 is connected to the lower end of the steam separator 5 .

The heat transfer tube bank 32A is provided inside the tube bank outer cylinder 31 . The heat transfer tube group 32A has a plurality of heat transfer tubes 32 extending in the vertical direction Z in an inverted U shape. Each heat transfer tube 32 is arranged to extend in the vertical direction Z from the upper end to the lower end of the lower shell 2a with the U-shaped arc portion directed upward. Both ends of each heat transfer tube 32 located on the lower end side of the lower shell 2a are inserted into the tube holes 8a of the tube plate 8 and fixed. As a result, both ends of each heat transfer tube 32 are opened below the tube sheet 8 . As shown in FIG. 2, the interval between the adjacent heat transfer tubes 32 is set to be small (for example, about 10 mm) except for the region where the flow slots 36 of the tube support plate 33, which will be described later, are formed. A large number of portions of the heat transfer tubes 32 extending in the up-down direction Z are arranged in the left-right direction X and the front-rear direction Y. As shown in FIG.

As shown in FIG. 1 , the tube support plate 33 is attached to the tube bundle outer cylinder 31 so that its plate thickness direction faces the vertical direction Z of the tube bundle outer cylinder 31 . A plurality (seven in the illustrated example) of the tube support plates 33 are arranged at intervals in the vertical direction Z. As shown in FIG. A plurality of tube support plates 33 support the heat transfer tubes 32 at their longitudinal intermediate portions. Specifically, the tube support plate 33 supports the heat transfer tubes 32 by inserting the heat transfer tubes 32 through the tube support plate 33 . The plurality of tube support plates 33 partition the inner space of the tube bundle outer cylinder 31 into a plurality of spaces aligned in the vertical direction Z. As shown in FIG.

As shown in FIG. 2, each tube support plate 33 is formed with a flow slot 36 penetrating in the plate thickness direction (vertical direction Z). The flow slot 36 is formed as an elongated hole with a long dimension in the left-right direction X. As shown in FIG. Further, the flow slots 36 are arranged in a row in the left-right direction X at intervals in the middle of the tube support plate 33 in the front-rear direction Y. As shown in FIG. The plurality of heat transfer tubes 32 described above are arranged so as to avoid the regions where the plurality of flow slots 36 are formed in the tube support plate 33 . Therefore, the distance between the heat transfer tubes 32 located on both sides of the region where the flow slots 36 are formed in the front-rear direction Y increases according to the size of the region where the flow slots 36 are formed.
As shown in FIG. 3 , a plurality of spaces of the tube bank outer cylinder 31 partitioned by the tube support plate 33 are connected to each other via flow slots 36 formed in the tube support plate 33 .

As shown in FIG. 1, the flow distribution plate 34 is arranged between the tube plate 8 and the lowermost tube support plate 33a (hereinafter referred to as the first tube support plate 33a). Like the tube support plate 33 , the flow distribution plate 34 is attached to the tube bank outer cylinder 31 so that the plate thickness direction faces the vertical direction Z of the tube bank outer cylinder 31 . The flow distribution plate 34 partitions the space in the vertical direction Z between the tube plate 8 and the first tube support plate 33a. An opening 37 penetrating in the vertical direction Z is formed in the central portion of the flow distribution plate 34 as viewed in the vertical direction Z. As shown in FIG. This opening 37 connects the spaces above and below the flow distribution plate 34 to each other. The size of the opening 37 of the flow distribution plate 34 when viewed in the vertical direction Z is larger than the size of the flow slot 36 of the tube support plate 33 .

The first lower hand hole 23, the second lower hand hole 24, and the upper hand hole 25 of the lower body 2a described above are positioned as follows with respect to the plurality of tube support plates 33 and the flow distribution plates 34, respectively. do. The first lower hand hole 23 is located between the tube sheet 8 and the flow distribution plate 34 in the vertical direction Z. As shown in FIG. In addition, the second lower hand hole 24 includes a first tube support plate 33a and a tube support plate 33b (hereinafter referred to as a second tube support plate 33b) adjacent to the upper side of the first tube support plate 33a in the vertical direction Z. located between The upper hand hole 25 is positioned above the uppermost tube support plate 33g in the vertical direction Z (hereinafter referred to as the seventh tube support plate 33g).

A flow passage 35 is formed in the heat exchange portion 3 . The flow passage 35 causes the secondary cooling water supplied from the water supply portion 4 to the inside of the lower shell 2a to flow down between the inner side of the lower shell 2a and the outer side of the tube bundle outer cylinder 31, and is folded back at the tube sheet 8. , inside the tube bundle outer cylinder 31, it is formed to pass through the opening 37 of the flow distribution plate 34 and the flow slot 36 (see FIGS. 2 and 3) of the tube support plate 33 and rise along the heat transfer tube bundle 32A. ing.

(water room mirror)
The water chamber mirror 6 is provided below the tube plate 8 . The interior of the water chamber mirror 6 is divided into an inlet side water chamber 6A and an outlet side water chamber 6B. One end of each heat transfer tube 32 communicates with the inlet-side water chamber 6A. On the other hand, the other end of each heat transfer tube 32 communicates with the outlet side water chamber 6B.

The water chamber mirror 6 is formed with an inlet nozzle 6Aa that opens the inlet side water chamber 6A to the outside of the water chamber mirror 6, and an outlet nozzle 6Ba that opens the outlet side water chamber 6B to the outside of the water chamber mirror 6. ing. A pipe (not shown) for sending the primary cooling water from the nuclear reactor to the heat exchange section 3 is connected to the inlet nozzle 6Aa. A pipe (not shown) is connected to the outlet nozzle 6Ba for returning the primary cooling water after heat exchange in the heat exchange section 3 to the reactor.

(water supply section)
The water supply unit 4 is provided inside the upper shell 2b (upper side of the heat exchange unit 3 in the shell 2). The water supply unit 4 introduces secondary cooling water from the outside of the body 2 and supplies the water to the heat exchange unit 3 .

(steam separator)
The steam separator 5 is provided inside the upper barrel 2b. The steam separator 5 separates the secondary cooling water, which is heated by the primary cooling water in the heat exchange section 3 and rises, into steam and hot water.

(moisture separator)
The moisture separator 7 is arranged above the steam separator 5 inside the upper shell 2b. The moisture separator 7 removes moisture from the steam separated by the steam separator 5 to bring it into a state close to dry steam.

In the steam generator 1, the primary cooling water heated in the nuclear reactor is sent to the inlet side water chamber 6A, circulated through the plurality of heat transfer tubes 32 of the heat exchange section 3, and reaches the outlet side water chamber 6B. . On the other hand, the secondary cooling water is supplied from the water supply unit 4 to the heat exchange unit 3, passes through the flow passage 35 of the heat exchange unit 3, and rises along the heat transfer tube group 32A. At this time, in the heat exchange section 3, heat is exchanged between the high-temperature primary cooling water and the secondary cooling water, and the cooled primary cooling water is returned to the reactor from the outlet side water chamber 6B. On the other hand, the secondary cooling water heated by the primary cooling water rises inside the tube bank outer cylinder 31 and is separated into steam and hot water in the steam separator 5 . Moisture is removed from the separated steam by the moisture separator 7, and then the steam is discharged to the outside of the barrel 2 through the steam outlet 22 and sent to the turbine generator.

<First Embodiment>
(Inspection device)
Next, an inspection apparatus 100 of a first embodiment for inspecting the steam generator 1 described above will be described with reference to FIGS. 3 to 9. FIG.
As shown in FIG. 3, the inspection device 100 of the first embodiment is a device for inspecting the outer surfaces of the heat transfer tubes 32 of the heat transfer tube group 32A housed in the lower shell 2a. The inspection apparatus 100 includes an inspection cable 110 , a holding guide mechanism 120 and an elevating mechanism 130 .

(Cable for inspection)
The inspection cable 110 shown in FIGS. 3, 4 and 6 is a flexible cable body having an inspection probe 111 at its tip. The inspection probe 111 can employ a device for inspecting the outer surface of the heat transfer tube 32 to be inspected. An imaging device such as a CCD camera capable of imaging the outer surface of the heat transfer tube 32 is used for the inspection probe 111 of the present embodiment. The inspection cable 110 includes a support cable for supporting the inspection probe 111, a power supply cable for supplying power to the inspection probe 111, a control signal cable for transmitting and receiving a control signal to and from the inspection probe 111, and an inspection of the inspection probe 111. A data transmission cable for data transmission of the results may optionally be included.
The inspection cable 110 is inserted through the second lower hand hole 24 into the lower torso 2a, as shown in FIG. 3, for example. The inspection cable 110 may be inserted into the lower trunk 2a through the first lower hand hole 23 (see FIG. 1), for example.

(Holding guide mechanism)
As shown in FIGS. 3-5, the holding guide mechanism 120 holds the inspection cable 110 movably in its longitudinal direction. The holding guide mechanism 120 mainly holds the tip side portion of the inspection cable 110 inserted through the first lower hand hole 23 or the second lower hand hole 24 . Further, the holding guide mechanism 120 is movable in the vertical direction Z with the heat transfer tube 32 as a guide. Further, the holding guide mechanism 120 is configured to be able to pass through the flow slots 36 of the tube support plate 33 . A specific configuration of the holding guide mechanism 120 will be described below.

As shown in FIGS. 4 to 6, the holding guide mechanism 120 includes a guide body 121, a pair of guide legs 122, a holding portion 123, and a moving mechanism .

(Guide body)
The guide body 121 is sized and shaped to pass through the flow slot 36 of the tube support plate 33 in the vertical direction Z. As shown in FIG. Each dimension of the guide body 121 in the left-right direction X and the front-rear direction Y is smaller than each dimension of the flow slot 36 (see FIGS. 8, 9, etc.). Further, the dimension of the guide body 121 in the horizontal direction X is approximately half the dimension of the flow slot 36 . The guide main body 121 is formed in the shape of a rectangular parallelepiped whose longitudinal direction is the vertical direction Z. As shown in FIG.

(a pair of guide legs)
As shown in FIGS. 4 and 5, the pair of guide legs 122 are provided so as to be retractable with respect to the guide body 121, respectively. The pair of guide legs 122 move between a deployed position P1 extending in opposite directions from the guide body 121 in the front-rear direction Y (first orthogonal direction) and a retracted position P2 housed inside the guide body 121. It is possible.
As shown in FIGS. 5 to 7, when the pair of guide legs 122 are arranged at the unfolded position P1, the dimension of the holding guide mechanism 120 in the longitudinal direction Y is larger than the dimension of the flow slot . Therefore, retention guide mechanism 120 cannot pass through flow slot 36 . On the other hand, when the pair of guide legs 122 are arranged at the retracted position P2, the dimension of the holding guide mechanism 120 in the longitudinal direction Y is equal to the dimension of the guide main body 121. becomes smaller. This allows retention guide mechanism 120 to pass through flow slot 36 .

In this embodiment, the driving force for moving the pair of guide legs 122 between the deployed position P1 and the retracted position P2 is the biasing force of a spring (not shown) or air pressure. The pair of guide legs 122 are biased toward the storage position P2 by the biasing force of the spring. Also, the pair of guide legs 122 moves from the retracted position P2 to the deployed position P1 against the biasing force of the spring due to the air pressure acting on the pair of guide legs 122 due to the supply of air. The driving force for moving the pair of guide legs 122 may be electric power, for example.

When the pair of guide legs 122 are arranged at the deployed position P1, the tip portions of the pair of guide legs 122 can contact the two heat transfer tubes 32 positioned on both sides of the guide body 121 in the front-rear direction Y. That is, in a state in which the pair of guide legs 122 are arranged at the deployed position P1, the holding guide mechanism 120 is sandwiched between the two heat transfer tubes 32 arranged in the front-rear direction Y, and the holding guide mechanism 120 is positioned between the two heat transfer tubes 32. can be held in between. Also, the pair of guide legs 122 contact the two heat transfer tubes 32 located on both sides of the guide body 121, so that the holding guide mechanism 120 can move in the vertical direction Z using these two heat transfer tubes 32 as guides. .

Furthermore, in this embodiment, the tip of each guide leg 122 is configured by a roller 127 rotatable about the left-right direction X as an axis. As a result, when the holding guide mechanism 120 is moved in the vertical direction Z with the pair of guide legs 122 arranged at the deployment position P1, the rollers 127 of the guide legs 122 roll on the heat transfer tubes 32, The holding guide mechanism 120 can be smoothly moved in the vertical direction Z by using the heat transfer tube 32 as a guide. The roller 127 of the present embodiment is formed in a constricted shape at an intermediate portion in the axial direction. As a result, the roller 127 can be suppressed or prevented from being displaced in the lateral direction X with respect to the heat transfer tube 32 , and the roller 127 can be stably held on the heat transfer tube 32 .

A plurality of pairs of guide legs 122 are arranged in the vertical direction Z of the guide body 121 . In FIGS. 4 and 5, three pairs of guide legs 122 are arranged at intervals in the vertical direction Z. As shown in FIG. The plurality of pairs of guide legs 122 are movable independently of each other between the deployed position P1 and the retracted position P2. That is, only a predetermined pair of guide legs 122 selected from the plurality of pairs of guide legs 122 can be moved between the deployed position P1 and the retracted position P2.

(Holding part)
As shown in FIGS. 4 and 6, the holding portion 123 is arranged at the end of the guide body 121 in the left-right direction X. As shown in FIGS. The holding portion 123 has a function of holding the inspection cable 110 movably in its longitudinal direction in the holding guide mechanism 120 . Specifically, the holding portion 123 has a tubular guide member 125 through which the inspection cable 110 can be inserted. This allows the inspection cable 110 to move in the longitudinal direction of the guide member 125 .

The guide member 125 has a first guide portion 1251 and a second guide portion 1252 . The first guide portion 1251 is formed in a tubular shape linearly extending in the up-down direction Z. As shown in FIG. The second guide portion 1252 is formed in a tubular shape that curves and extends from the upper end (tip) of the first guide portion 1251 . The tip of the second guide portion 1252 faces one side in the front-rear direction Y. As shown in FIG. The guide member 125 may be rotatable about the up-down direction Z so that the tip of the second guide portion 1252 can be selectively directed to either one side or the other side in the front-rear direction Y. The second guide portion 1252 may extend in the front-rear direction Y with respect to the first guide portion 1251 , but may be positioned outside the guide body 121 in the front-rear direction Y, for example, so as not to obstruct passage of the holding guide mechanism 120 through the flow slot 36 . preferably not overhang.
The guide member 125 guides the inspection cable 110 inserted into the lower trunk 2a from the first lower hand hole 23 or the second lower hand hole 24 along the first guide portion 1251 and the second guide portion 1252 in order. invite. The second guide portion 1252 guides the inspection cable 110 in the front-rear direction Y. As shown in FIG. As a result, the tip of the inspection cable 110 can be advanced from the tip of the second guide portion 1252 to one side (or the other side) in the front-rear direction Y. As shown in FIG.

(moving mechanism)
As shown in FIG. 4, the moving mechanism 124 moves the holding portion 123 closer to or away from the guide body 121 in the left-right direction X (second orthogonal direction). The movement mechanism 124 illustrated in FIG. 4 is a link mechanism having a pantograph structure provided between the guide body 121 and the holding portion 123 . The linkage has two links 126 that are rotatably connected across each other. Two link mechanisms are arranged in the front-rear direction Y with an interval therebetween.
Although not shown, the moving mechanism 124 of the present embodiment moves the holding portion 123 in the left-right direction X with respect to the guide body 121 using the biasing force of the spring and the air pressure as driving force. Specifically, the holding portion 123 is biased toward the guide main body 121 by the biasing force of the spring. Further, the holding portion 123 moves away from the guide main body 121 against the biasing force of the spring due to the air pressure acting on the holding portion 123 due to the supply of air. Note that the moving mechanism 124 may move the holding portion 123 with respect to the guide main body 121 using another driving force such as electric power.

(lifting mechanism)
As shown in FIG. 3, the lifting mechanism 130 is a mechanism for moving the holding guide mechanism 120 in the vertical direction Z. As shown in FIG. The lifting mechanism 130 of this embodiment has a support wire 131 and a reel 132 . The support wire 131 suspends and supports the holding guide mechanism 120 inside the lower trunk 2a. The support wire 131 is pulled out from the upper hand hole 25 to the outside of the lower torso 2a. A reel 132 is positioned outside the upper handhole 25 for winding and unwinding the support wire 131 . As a result, the support wire 131 is wound up by the reel 132, so that the holding guide mechanism 120 can be moved upward. In addition, the holding guide mechanism 120 can be moved downward by feeding out the support wire 131 from the reel 132 .
The support wire 131 is inserted into the lower barrel 2a through the upper hand hole 25 positioned above the seventh tube support plate 33g. Thereby, the lifting mechanism 130 can move the holding guide mechanism 120 in the vertical direction Z from above the seventh tube support plate 33g to below the flow distribution plate 34 .

The lifting mechanism 130 of this embodiment further includes a rail frame 133 and guide rollers 134 . The rail frame 133 is detachably attached to the lower trunk 2a while passing through both of the two upper hand holes 25 arranged in the horizontal direction X. As shown in FIG. The guide roller 134 is attached to the rail frame 133 so as to be movable in its longitudinal direction (lateral direction X). The support wire 131 inserted into the lower body 2a through the upper hand hole 25 is hooked on the guide roller 134, thereby deflecting the support wire 131 downward.
By adjusting the position of the guide roller 134 in the horizontal direction X, the lift mechanism 130 can adjust the position at which the holding guide mechanism 120 is suspended in the horizontal direction X. FIG.

(Steam generator inspection method)
Next, a method for inspecting the steam generator 1 by the inspection device 100 of this embodiment will be described.
In the method for inspecting the steam generator 1, the outer surfaces of the plurality of heat transfer tubes 32 of the heat transfer tube group 32A housed in the lower shell 2a are inspected. At the time of inspection, first, a guide step of guiding the holding guide mechanism 120 to a predetermined area by the lifting mechanism 130 is performed. The predetermined area is an area within the lower shell 2 a corresponding to the portion of the heat transfer tube 32 to be inspected by the inspection probe 111 .
In the guiding step, first, the position of the guide roller 134 is set so as to correspond to a predetermined area in the horizontal direction X. As shown in FIG. Thereby, the holding guide mechanism 120 suspended below the guide roller 134 by the support wire 131 can be arranged at a position corresponding to a predetermined area in the horizontal direction X. As shown in FIG.

Next, the holding guide mechanism 120 is guided to a predetermined area in the vertical direction Z by reeling out or winding the support wire 131 by the reel 132 of the lifting mechanism 130 . At this time, as shown in FIG. 5, a plurality of pairs of guide legs 122 are arranged at the deployed position P1 to hold the holding guide mechanism 120 between the two heat transfer tubes 32 . In this state, the holding guide mechanism 120 can move in the vertical direction Z using these two heat transfer tubes 32 as guides. When the holding guide mechanism 120 passes through the flow slots 36 of the tube support plate 33 when the holding guide mechanism 120 is moved in the vertical direction Z, as shown in FIG. The guide leg 122 may be arranged at the retracted position P2.

After the guiding step, an inspection step of inspecting the outer surface of the heat transfer tube 32 with the inspection probe 111 in a predetermined area is performed.
In the inspection step, as shown in FIG. 6, by advancing the inspection probe 111 from the tip of the second guide portion 1252 of the guide member 125 of the holding guide mechanism 120, the inspection probe 111 detects the heat transfer tube 32 located in the predetermined area. can be inspected.

Further, the position of the inspection probe 111 in the front-rear direction Y can be adjusted by moving the inspection cable 110 in the longitudinal direction with respect to the guide member 125 . Thereby, the outer surfaces of the plurality of heat transfer tubes 32 arranged in the front-rear direction Y in a predetermined area can be inspected. Further, by changing the orientation of the tip of the second guide portion 1252 of the guide member 125, the outer surface of the heat transfer tube 32 located on both sides of the holding guide mechanism 120 (flow slot 36) in the front-rear direction Y can be inspected. can.

Further, as shown in FIGS. 8 and 9, by moving the holding portion 123 holding the inspection cable 110 in the horizontal direction X with respect to the guide main body 121 by the moving mechanism 124 (see FIG. 4), can be adjusted. As a result, even if the guide body 121 is held at a predetermined position in the horizontal direction X by the pair of guide legs 122, the outer surface of the heat transfer tube 32 within a predetermined range in the horizontal direction X can be inspected by the inspection probe 111. becomes possible. Reference numerals R1 and R2 in FIGS. 8 and 9 denote inspectable ranges that can be inspected by the inspection probe 111 in the horizontal direction X, respectively, and correspond to moving ranges of the holding portion 123 .

In addition, since the holding part 123 is movable in the horizontal direction X with respect to the guide body 121, the plurality of flow slots 36 formed in the same tube support plate 33 are arranged at intervals. can be positioned between adjacent flow slots 36 in the left-right direction X. As a result, the inspection probe 111 can detect not only the outer surface of the heat transfer tube 32 positioned in the front-rear direction Y with respect to the flow slots 36, but also the heat transfer tube 32 positioned in the front-rear direction Y with respect to the gap between the adjacent flow slots 36. External surfaces can also be inspected.

For example, as shown in FIG. 8, when the guide body 121 is held at a predetermined position in the left-right direction X, the movement range of the holding portion 123 in the left-right direction X with respect to the guide body 121 is the flow slot in the left-right direction X. It is not necessary to cover the entire 36 gaps. In this case, for example, as shown in FIG. 9, the arrangement of the holding guide mechanism 120 may be horizontally reversed. As a result, even if the movement range of the holding part 123 in the left-right direction X does not cover the entire left-right direction X of the clearance of the flow slot 36, it is positioned in the front-rear direction Y with respect to the entire left-right direction X of the clearance of the flow slot 36. The outer surface of heat transfer tube 32 can be inspected.
Specifically, in FIG. 8, the inspectable range R1 in the horizontal direction X by the inspection probe 111 corresponds to only half of the clearance of the flow slot 36 in the horizontal direction X. As shown in FIG. On the other hand, in FIG. 9 in which the arrangement of the holding guide mechanism 120 is left-right reversed, the inspectable range R2 in the left-right direction X by the inspection probe 111 corresponds to the remaining half of the clearance of the flow slot 36 in the left-right direction X. FIG. Thereby, the outer surface of the heat transfer tube 32 positioned in the front-rear direction Y with respect to the entire left-right direction X of the gap of the flow slot 36 can be inspected.

In the inspection method of this embodiment performed as described above, the lifting mechanism 130 moves the holding guide mechanism 120 in the vertical direction Z and the horizontal direction X, and the moving mechanism 124 moves the holding portion 123 horizontally with respect to the guide main body 121 . By moving in the direction X, it is possible to inspect the entire outer surface of the plurality of heat transfer tubes 32 in the lower shell 2a.

According to the inspection apparatus 100 and the inspection method of the first embodiment, the holding guide mechanism 120 holding the inspection cable 110 is vertically moved by the lifting mechanism 130 so as to pass through the flow slot 36 of the tube support plate 33 . It is made movable in the direction Z. As a result, even if the inside of the lower trunk 2a is partitioned in the vertical direction Z by the tube support plate 33, it is possible to prevent the tube support plate 33 from restricting the accessible range of the inspection probe 111. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wide range.

Further, according to the inspection apparatus 100 and the inspection method of the first embodiment, the holding guide mechanism 120 is movable in the vertical direction Z using the heat transfer tubes 32 as guides. As a result, the holding guide mechanism 120 can be stably moved in the vertical direction Z at a desired position within the lower barrel 2a. Thereby, the inspection of the outer surface of the heat transfer tube 32 by the inspection probe 111 can be performed in a stable state.

Further, according to the inspection apparatus 100 of the first embodiment, the pair of guide legs 122 contact the two heat transfer tubes 32 positioned on both sides of the guide main body 121 in a state of being arranged at the deployment position P1. As a result, the holding guide mechanism 120 can be reliably moved in the vertical direction Z using the heat transfer tube 32 as a guide. Further, when the pair of guide legs 122 are arranged at the deployed position P1, the holding guide mechanism 120 can be sandwiched between the two heat transfer tubes 32, so that the posture of the holding guide mechanism 120 can be reliably stabilized. can. Thereby, the inspection of the outer surface of the heat transfer tube 32 by the inspection probe 111 can be performed in a stable state.
Further, according to the inspection apparatus 100 of the first embodiment, the pair of guide legs 122 are arranged at the storage position P2, so that the pair of guide legs 122 do not block the passage of the holding guide mechanism 120 to the flow slot 36. can be prevented.

Moreover, according to the inspection apparatus 100 of the first embodiment, the holding guide mechanism 120 includes a plurality of pairs of guide legs 122 . This allows the holding guide mechanism 120 to pass through the flow slots 36 of the tube support plate 33 in a stable condition. This point will be described below.
When passing the holding guide mechanism 120 through the flow slot 36, for example, as shown in FIG. 7, it is necessary to arrange the pair of guide legs 122 located inside the flow slot 36 at the retracted position P2. Here, if a plurality of pairs of guide legs 122 are arranged in the vertical direction Z, the other pairs of guide legs 122 positioned above or below the flow slot 36 (only the lower side in FIG. 7) are It can be arranged at the deployment position P1. Accordingly, even when the holding guide mechanism 120 is passed through the flow slot 36, the posture of the holding guide mechanism 120 can be stabilized.

Further, according to the inspection apparatus 100 of the first embodiment, the holding portion 123 that holds the inspection cable 110 can be moved in the horizontal direction X with respect to the guide main body 121 by the moving mechanism 124 . Therefore, even if the guide body 121 is held at a predetermined position in the horizontal direction X, the outer surface of the heat transfer tube 32 within a predetermined range in the horizontal direction X can be inspected by the inspection probe 111 . This makes it possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wide range. Specifically, it is possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wide range while reducing the number of times the guide body 121 is moved up and down within the lower shell 2a.

<Second embodiment>
Next, an inspection apparatus according to a second embodiment, which inspects the steam generator 1 shown in FIGS. 1 to 3, will be described with reference to FIGS. 10 to 20. FIG.

(Inspection device)
As shown in FIGS. 10 to 20, inspection devices 100A to 100D of the second embodiment are devices for inspecting the outer surfaces of a plurality of heat transfer tubes 32 housed in the lower shell 2a. , and a guide member 140 . The configuration of the inspection cable 110 is the same as that of the inspection apparatus 100 of the first embodiment.

(Guide member)
The guide member 140 has a first guide portion 141 and a second guide portion 142 . The first guide portion 141 linearly extends from the hand holes 23, 24 (first and second lower hand holes 23, 24) located in the lower portion of the lower barrel 2a toward the inside of the lower barrel 2a. The second guide portion 142 extends curvedly from the tip of the first guide portion 141 with respect to the first guide portion 141 . The guide member 140 guides the inspection cable 110 to the first guide portion 141 and the second guide portion 142 in order. The guide member 140 of the second embodiment is formed in a tubular shape through which the inspection cable 110 can be inserted.

The guide member 140 of the second embodiment includes a guide member 140A of the first example shown in FIGS. 10 and 11, a guide member 140B of the second example shown in FIG. There is a member 140C and a fourth example guide member 140D shown in FIGS. 18-20. The guide members 140A to 140D of each example and the inspection method of the steam generator 1 using the guide members 140A to 140D will be described below in order.

(Guiding member of the first example)
As shown in FIGS. 10 and 11, the guide member 140A of the first example includes a linearly extending tubular first guide portion 141A and a tubular second guide portion 142A curvedly extending from the tip of the first guide portion 141A. and have The second guide portion 142A is curved only once so that its tip faces in a direction perpendicular to the longitudinal direction of the first guide portion 141A. 10 and 11, the tip of the second guide portion 142A faces one side in the front-rear direction Y. In FIGS.

(Inspection method using the guide member of the first example)
Next, a method for inspecting the steam generator 1 by the inspection device 100A including the guide member 140A of the first example will be described.
In the inspection method using the guide member 140A of the first example, an installation step of installing the guide member 140A and an inspection step of inspecting the outer surface of the heat transfer tube 32 with the inspection probe 111 are performed in order.
In the installation step, the first guide portion 141A of the guide member 140A extends from the hand holes 23, 24 located at the bottom of the lower trunk 2a toward the inside of the lower trunk 2a, and the tip of the second guide portion 142A is extended toward the inside of the lower trunk 2a. The guide member 140A is installed so that it is arranged at a predetermined position inside the lower barrel 2a. The predetermined position is a position within the lower shell 2 a corresponding to the portion of the heat transfer tube 32 to be inspected by the inspection probe 111 .
In the inspection step, by advancing the inspection cable 110 guided by the guide member 140A from the tip of the second guide portion 142A, the inspection probe 111 inspects the outer surface of the heat transfer tube 32 located on the tip side of the second guide portion 142A. to inspect.

Next, two types of inspection examples of the inspection method by the guide member 140A of the first example will be described with reference to FIGS. 10 and 11, respectively.

(First inspection example)
In the first inspection example shown in FIG. 10, in the installation step, the guide member 140A is inserted through the second lower hand hole 24 into the interior of the lower trunk 2a with the second guide portion 142A side leading. After that, the guide member 140A is moved in the horizontal direction X along the upper surface of the first tube support plate 33a, so that the tip of the second guide portion 142A is arranged at a predetermined position inside the lower barrel 2a in the horizontal direction X. . Further, the guide member 140A is arranged so that the tip of the second guide portion 142A faces one side or the other side in the front-rear direction Y. As shown in FIG. Thereafter, in the inspection step, the inspection cable 110 is moved in the longitudinal direction with respect to the guide member 140A to adjust the position of the inspection probe 111 in the front-rear direction Y. As shown in FIG. As a result, the outer surfaces of all the heat transfer tubes 32 located on the upper surface side of the first tube support plate 33a can be inspected.

The first inspection example described above is not limited to the upper surface side of the first tube support plate 33a, but can also be used to inspect the outer surface of the heat transfer tubes 32 located on the upper surface side of the seventh tube support plate 33g and the upper surface side of the tube plate 8. Applicable. For example, when inspecting the outer surface of the heat transfer tube 32 on the upper surface side of the seventh tube support plate 33g, in the installation step, the guide member 140A is moved downward from the upper hand hole 25 located above the seventh tube support plate 33g. It can be inserted inside the barrel 2a. Further, for example, when inspecting the outer surface of the heat transfer tube 32 on the upper surface side of the tube sheet 8, in the installation step, the guide member 140A is moved from the first lower hand hole 23 located above the tube sheet 8 to the lower body. 2a can be inserted.

(Second inspection example)
In the second inspection example shown in FIG. 11, in the installation step, the guide member 140A is inserted through the first lower hand hole 23 into the interior of the lower trunk 2a with the second guide portion 142A side leading. After that, the first guide portion 141A of the guide member 140A is extended obliquely upward from the first lower hand hole 23 and passed through the opening 37 of the flow distribution plate 34 to extend the tip of the first guide portion 141A and the second guide portion 141A. The guide portion 142A is made to reach a predetermined position on the upper surface side of the flow distribution plate 34 . Also, although not shown, the guide member 140A is arranged such that the tip of the second guide portion 142A faces one side or the other side in the front-rear direction Y, as in the case of the first inspection example shown in FIG. Thereafter, in the inspection step, the inspection cable 110 is moved in the longitudinal direction with respect to the guide member 140A to adjust the position of the inspection probe 111 in the front-rear direction Y. As shown in FIG. As a result, the outer surface of the heat transfer tube 32 located in the partial area on the upper surface side of the flow distribution plate 34 can be inspected. Here, the partial region on the upper surface side of the flow distribution plate 34 is the region located on both sides of the opening 37 in the left-right direction X on the upper surface of the flow distribution plate 34 .

(Guiding member of the second example)
As shown in FIG. 12, similarly to the guide member 140A of the first example, the guide member 140B of the second example has a tubular first guide portion 141B extending linearly and a curved portion extending from the tip of the first guide portion 141B. and a tubular second guide portion 142B extending along the length thereof. However, in the guide member 140B of the second example, the second guide portion 142B is curved twice. In addition, the tip of the second guide portion 142B faces the opposite side of the first guide portion 141B in the longitudinal direction of the first guide portion 141B. Specifically, the second guide portion 142B extends in a direction orthogonal to the first guide portion 141B in the first curve, and extends in a direction along the first guide portion 141B in the second curve.

(Inspection method using the guide member of the second example)
Next, the inspection method of the steam generator 1 by the inspection device 100B including the guide member 140B of the second example will be described.
In the inspection method using the guide member 140B of the second example, the same installation step and inspection step as in the inspection method using the guide member 140A of the first example are sequentially performed. However, in the inspection method using the guide member 140B of the second example, the outer surface of the heat transfer tube 32 on the upper surface side of the tube sheet 8 is inspected.

Therefore, in the installation step, the guide member 140B is inserted into the lower shell 2a through the first lower hand hole 23 located above the tube sheet 8. As shown in FIG. Here, as shown in FIGS. 11 and 12, on the upper surface of the tube sheet 8, between the two first lower hand holes 23 aligned in the left-right direction X, which is an intermediate portion of the tube sheet 8 in the front-rear direction Y, the is provided with a tube lane block 81 . On the other hand, in the installation step, the guide member 140B is installed so that the second guide portion 142B does not interfere with the tube lane block 81, as shown in FIG. Specifically, the tip of the second guide portion 142B is arranged so as to face in the left-right direction X (rightward in FIG. 12) and to be shifted in the front-rear direction Y with respect to the tube lane block 81. be.

In the inspection step after the installation step, the position of the inspection probe 111 in the horizontal direction X can be adjusted by moving the inspection cable 110 in its longitudinal direction with respect to the guide member 140B. Further, the position of the second guide portion 142B in the front-rear direction Y can be adjusted by changing the length of the portion extending in the front-rear direction Y of the second guide portion 142B. As a result, the outer surface of the heat transfer tubes 32 positioned on the upper surface side of the tube sheet 8, particularly the outer surface of the heat transfer tubes 32 positioned near the tube lane block 81, can be inspected.

(Guide member of the third example)
As shown in FIGS. 13 to 17, the guide member 140C of the third example, like the guide member 140B of the second example, has a linearly extending tubular first guide portion 141C and a tip of the first guide portion 141C. and a curvedly extending tubular second guide portion 142C. Also, the second guide portion 142C is curved twice. However, in the guide member 140C of the third example, as shown in FIGS. 13 and 15, the first guide portion 141C extends in the horizontal direction (horizontal direction X in FIGS. 13 and 15), and the second guide portion 142C extends horizontally. It is directed upward by curving with respect to one guide portion 141C and extends upward with respect to the first guide portion 141C. Furthermore, as shown in FIGS. 14, 16 and 17, the second guide portion 142C extends upward and curves to one side in the front-rear direction Y. As shown in FIGS. As a result, the tip of the second guide portion 142C faces one side in the front-rear direction Y. As shown in FIG. In addition, the tip portion of the second guide portion 142C is rotatable with respect to the base end portion so that the tip of the second guide portion 142C can be selectively directed to either one side or the other side of the front-rear direction Y. It can be

(Inspection method using the guide member of the third example)
Next, the inspection method of the steam generator 1 by the inspection device 100C including the guide member 140C of the third example will be described.
In the inspection method using the guide member 140C of the third example, the same installation step and inspection step as in the inspection method using the guide member 140A of the first example are sequentially performed. However, in the inspection method using the guide member 140C of the third example, the outer surfaces of the heat transfer tubes 32 on the lower surface side and the upper surface side of the second tube support plate 33b are inspected. Therefore, in the installation step, the guide member 140C is inserted into the lower barrel 2a through the second lower hand hole 24 located above the first tube support plate 33a. Further, the guide member 140C is installed such that the first guide portion 141C of the inserted guide member 140C extends in the left-right direction X and the second guide portion 142C extends upward with respect to the first guide portion 141C. do.

Next, two types of inspection examples of the inspection method by the guide member 140C of the third example will be described with reference to FIGS. 13, 14 and 15 to 17 respectively.

(First inspection example)
In the first inspection example shown in FIGS. 13 and 14, the outer surface of the heat transfer tube 32 on the lower surface side of the second tube support plate 33b is inspected. Therefore, in the installation step, in a state in which the guide member 140C is inserted from the second lower hand hole 24 into the inside of the lower trunk 2a, the tip of the second guide portion 142C extending upward with respect to the first guide portion 141C is It is positioned on the lower surface side of the two-pipe support plate 33b. The position of the tip of the second guide portion 142C can be set by changing the length of the second guide portion 142C in the vertical direction Z, for example. Also, the position of the tip of the second guide portion 142C in the left-right direction X can be set by changing the length of the first guide portion 141C inserted into the lower trunk 2a in the left-right direction X, for example. Thereafter, in the inspection step, the position of the inspection probe 111 in the front-rear direction Y can be adjusted by moving the inspection cable 110 in the longitudinal direction with respect to the guide member 140C. Thereby, it is possible to inspect the outer surface of the heat transfer tubes 32 located in at least a partial area on the lower surface side of the second tube support plate 33b.

Here, the partial area on the lower surface side of the second tube support plate 33b means the vicinity of both sides of the second lower hand hole 24 (or flow slot 36) in the front-rear direction Y on the lower surface of the second tube support plate 33b. It is a region (neighboring region in the front-rear direction Y). The position of the second lower hand hole 24 or flow slot 36 in the longitudinal direction Y corresponds to the position where the tip of the second guide portion 142C is arranged.
Note that the tip of the inspection cable 110 (inspection probe 111) tends to hang downward due to its own weight or the like as it separates from the tip of the second guide portion 142C. Therefore, it is located in a region (remaining region on the lower surface side of the second tube support plate 33b) that is further away in the front-rear direction Y than the above-described “neighboring region in the front-rear direction Y” of the lower surface of the second tube support plate 33b. It is difficult to inspect the outer surface of heat transfer tube 32 .
However, if the inspection cable 110 is configured so that it does not hang down even if the tip of the inspection cable 110 (inspection probe 111) is separated from the tip of the second guide portion 142C, the second tube support plate 33b It is possible to inspect the outer surface of all the heat transfer tubes 32 located on the lower surface side of the .

(Second inspection example)
In the second inspection example shown in FIGS. 15 to 17, the outer surface of the heat transfer tube 32 on the upper surface side of the second tube support plate 33b is inspected. For this reason, in the installation step, with the guide member 140C inserted into the interior of the lower trunk 2a through the second lower hand hole 24, the tip portion of the second guide portion 142C extending upward with respect to the first guide portion 141C is It is made to pass through the flow slot 36 of the second tube support plate 33b and reach the upper surface side of the second tube support plate 33b. The position of the tip portion of the second guide portion 142C can be set by changing the length of the second guide portion 142C in the vertical direction Z. Also, the position of the tip of the second guide portion 142C in the left-right direction X can be set by changing the length of the first guide portion 141C inserted into the lower trunk 2a in the left-right direction X, for example. A tip portion of the second guide portion 142C located on the upper surface side of the second tube support plate 33b is curved in one side of the front-rear direction Y (direction crossing the up-down direction Z). As a result, the tip of the second guide portion 142C faces one side in the front-rear direction Y on the upper surface side of the second tube support plate 33b.

Thereafter, in the inspection step, the position of the inspection probe 111 in the front-rear direction Y can be adjusted by moving the inspection cable 110 in the longitudinal direction with respect to the guide member 140C. As described above, it is possible to inspect the outer surface of the heat transfer tube 32 located in a partial region on the upper surface side of the second tube support plate 33b.

Here, the partial area on the upper surface side of the second tube support plate 33b is an area adjacent to each flow slot 36 in the front-rear direction Y on the upper surface of the second tube support plate 33b. In the guide member 140C of the third example, an area adjacent in the front-rear direction Y to an area where the flow slots 36 are not formed in the left-right direction X (for example, gaps between the flow slots 36) on the upper surface of the second tube support plate 33b. It is not possible to inspect the outer surface of the heat transfer tubes 32 located on (the remaining area of the upper surface of the second tube support plate 33b).

The guide member 140C of the third example described above can be applied not only to the lower surface side and the upper surface side of the second tube support plate 33b, but also to the inspection of the outer surface of the heat transfer tubes 32 located on the lower surface side of the flow distribution plate 34. In this case, in the installation step, the guide member 140C of the third example may be inserted through the first lower hand hole 23 positioned below the flow distribution plate 34 into the interior of the lower barrel 2a.

(Guide member of the fourth example)
As shown in FIGS. 18 to 20, the guide member 140D of the fourth example, like the guide member 140C of the third example, has a linearly extending tubular first guide portion 141D and a tip of the first guide portion 141D. and a curved tubular second guide portion 142D. Further, in the fourth example of the guide member 140D, as shown in FIG. 18, the first guide portion 141D extends in the horizontal direction (left-right direction X in FIG. 18), and the second guide portion 142D extends along the first guide portion 141D. , and extends upward with respect to the first guide portion 141D.

As shown in FIGS. 18 and 19, the second guide portion 142D has a U-shaped curved portion 143D that extends upward, curves into an inverted U shape, and extends downward. The U-shaped curved portion 143D is formed such that the direction in which the second guide portion 142D faces gradually changes from upward to downward toward one side in the left-right direction X (longitudinal direction of the first guide portion 141D). . The length of the U-shaped curved portion 143D in the vertical direction Z is shorter than the length of the second guided portion 142D extending upward from the first guide portion 141D to the U-shaped curved portion 143D.

Furthermore, as shown in FIGS. 19 and 20, the second guide portion 142D has a tip curved portion 144D that curves to one side in the front-rear direction Y from the tip of the downward U-shaped curved portion 143D. As a result, the tip of the second guide portion 142D faces one side in the front-rear direction Y. As shown in FIG. In addition, the distal end curved portion 144D is rotatable with respect to the U-shaped curved portion 143D so that the distal end of the second guide portion 142D can be selectively directed to either one side or the other side in the front-rear direction Y. It's okay.

(Inspection method using the guide member of the fourth example)
Next, a method for inspecting the steam generator 1 by the inspection device 100D including the guide member 140D of the fourth example will be described.
In the inspection method using the guide member 140D of the fourth example, the same installation step and inspection step as in the inspection method using the guide member 140A of the first example are sequentially performed. However, in the inspection method using the guide member 140D of the fourth example, the outer surface of the heat transfer tube 32 on the upper surface side of the second tube support plate 33b is inspected. Therefore, in the installation step, as shown in FIG. 18, the guide member 140D is inserted into the lower barrel 2a through the second lower hand hole 24 located above the first tube support plate 33a. Further, the guide member 140D is installed such that the first guide portion 141D of the inserted guide member 140D extends in the left-right direction X and the second guide portion 142D extends upward with respect to the first guide portion 141D. do.

Further, as shown in FIGS. 18 and 20, in a state in which the guide member 140D is inserted into the lower trunk 2a through the second lower hand hole 24, the second guide portion 142D including the U-shaped curved portion 143D and the tip curved portion 144D is inserted. is passed through the flow slot 36 of the second tube support plate 33b to reach the upper surface side of the second tube support plate 33b. Further, as shown in FIGS. 18 and 19, the downward portion of the U-shaped curved portion 143D and the distal curved portion 144D are arranged adjacent to the flow slot 36 in the left-right direction X on the upper surface of the second tube support plate 33b. Position it above the mating area. As a result, the tip of the second guide portion 142D faces one side in the front-rear direction Y in the area adjacent to the flow slot 36 in the left-right direction X on the upper surface side of the second tube support plate 33b.

After that, in the inspection step, the position of the inspection probe 111 in the front-rear direction Y can be adjusted by moving the inspection cable 110 in the longitudinal direction with respect to the guide member 140D. As described above, the remaining area on the upper surface side of the second tube support plate 33b (the area adjacent in the front-rear direction Y to the area where the flow slots 36 are not formed in the left-right direction X on the upper surface of the second tube support plate 33b) ; the region indicated by symbol R3 in FIG. 19) can be inspected.

According to the inspection apparatuses 100A to 100D according to the second embodiment, the guide member 140 for guiding the inspection cable 110 extends from the first and second lower hand holes 23, 24 of the lower trunk 2a toward the inside of the lower trunk 2a. and a second guide portion 142 extending curvedly from the tip of the first guide portion 141 with respect to the first guide portion 141 . As a result, the inspection cable 110 is inserted through the first and second lower hand holes 23 and 24 into the lower body 2a, and is guided through the first guide portion 141 and the second guide portion 142 of the guide member 140 in order. By being guided along, the inspection probe 111 at the tip of the inspection cable 110 can be advanced in a direction different from the direction in which the first guide portion 141 extends inside the lower trunk 2a, that is, in a desired direction. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wide range.

Further, in the inspection apparatuses 100C and 100D provided with the guide members 140C and 140D of the third and fourth examples among the inspection apparatuses 100A to 100D according to the second embodiment, the second guide portion 142 is positioned relative to the first guide portion 141. It is directed upwards by bending As a result, the outer surface of the heat transfer tube 32 located above the first and second lower hand holes 23 and 24 of the lower barrel 2a can be inspected by the inspection probe 111. As shown in FIG.

Further, in the inspection apparatuses 100C and 100D provided with the guide members 140C and 140D of the third example and the fourth example among the inspection apparatuses 100A to 100D according to the second embodiment, the tip portion of the second guide portion 142 is the second pipe. It can be passed through the flow slots 36 of the support plate 33b to reach the top side of the second tube support plate 33b. As a result, the outer surface of the heat transfer tube 32 can be inspected with the inspection probe 111 on the upper surface side of the second tube support plate 33b located above the second lower hand hole 24. As shown in FIG.

Further, in the inspection apparatuses 100C and 100D provided with the guide members 140C and 140D of the third and fourth examples among the inspection apparatuses 100A to 100D according to the second embodiment, the second guide portion 142 is the second tube support plate 33b. is curved in the front-rear direction Y (the direction crossing the up-down direction Z). This makes it possible to advance the inspection probe 111 at the tip of the inspection cable 110 in the direction along the upper surface of the second tube support plate 33b. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wide range.

Further, according to the inspection method according to the second embodiment, the tip of the second guide portion 142 of the guide member 140 can be arranged at a predetermined position inside the lower trunk 2a in the installation step. As a result, in the inspection step, the inspection handpiece is inserted into the lower barrel 2a through the first and second lower hand holes 23 and 24 and guided by the first guide portion 141 and the second guide portion 142 of the guide member 140. The inspection probe 111 at the tip of the cable 110 can be advanced from the tip of the second guide portion 142 into the inside of the lower body 2a to inspect the outer surface of the heat transfer tube 32 at a predetermined position and its surroundings.

<Third embodiment>
Next, an inspection apparatus according to a third embodiment for inspecting the steam generator 1 shown in FIGS. 1 to 3 will be described with reference to FIGS. 21 to 24. FIG.

(Inspection device)
As shown in FIGS. 21 to 24, the inspection device 100E of the third embodiment is a device for inspecting the outer surfaces of a plurality of heat transfer tubes 32 accommodated in the lower shell 2a, and includes an inspection cable 110 and a guide It has a member 140E and a cable housing 150E. The configuration of the inspection cable 110 is the same as that of the inspection apparatus 100 of the first embodiment.

(Guide member)
The guide member 140E has a first guide portion 141E and a second guide portion 142E. The first guide portion 141E extends linearly from the hand holes 23, 24 (the first and second lower hand holes 23, 24) located at the bottom of the lower trunk 2a toward the inside of the lower trunk 2a. The second guide portion 142E extends from the tip of the first guide portion 141E while curving with respect to the first guide portion 141E. The guide member 140E is a member that sequentially guides the inspection cable 110 to the first guide portion 141E and the second guide portion 142E via the cable container 150E, which will be described later. In other words, the guide member 140E is a member that guides the cable container 150E, into which the inspection cable 110 can be inserted, along the first guide portion 141E and the second guide portion 142E in order.

(cable container)
The cable container 150E extends in the longitudinal direction of the inspection cable 110 and is formed into a shape into which the inspection cable 110 can be inserted. The cable container 150E has an internal space extending in its longitudinal direction and into which an inspection cable is inserted. The internal space of the cable container 150E into which the inspection cable 110 is inserted is opened at the tip of the cable container 150E. As a result, the inspection probe 111 at the tip of the inspection cable 110 can be exposed or advanced from the tip of the cable container 150E.

The cable container 150E has a characteristic of being more easily bent than the guide member 140E. Therefore, when the cable housing body 150E is guided along the first guide portion 141E and the second guide portion 142E of the guide member 140E in order, the cable housing body 150E curves along the second guide portion 142E.
In addition, the cable container 150E has a characteristic that it is less likely to bend than the inspection cable 110 does. Therefore, even if the portion of the cable containing body 150E extending from the tip of the second guide portion 142E advances upward as illustrated in FIGS. can be suppressed. That is, the cable containing body 150E advanced from the tip of the second guide portion 142E can be moved upward in a straight line. Thereby, the inspection cable 110 can be linearly guided by the cable container 150E extending from the tip of the second guide portion 142E.

The cable housing 150E is configured to be bendable only in one direction (the direction along the second guide portion 142E). Specifically, the cable accommodation body 150E includes a plurality of divided bodies 151E that are rotatably connected to each other along the longitudinal direction. The adjacent divided bodies 151E are arranged in a direction orthogonal to the longitudinal direction of the first guide portion 141E (for example, the horizontal direction X) and the direction in which the second guide portion 142E curves with respect to the first guide portion 141E (for example, the vertical direction Z). (for example, the front-rear direction Y) are rotatable relative to each other.
Such a cable container 150E is configured to bend only in the direction along the second guide portion 142E without being twisted while being guided along the guide member 140E. This prevents the inspection cable 110 housed in the cable housing 150E from being twisted, thereby enabling a more reliable inspection.

For example, a separation prevention wire (not shown) extending over the entire length of the cable housing 150E may be arranged in the internal space of the cable housing 150E composed of a plurality of divided bodies 151E. The separation prevention wire is connected to all split bodies 151E. As a result, even if the adjacent split bodies 151E are separated due to some factor (for example, an external impact, etc.), the separated split bodies 151E can be held by the separation prevention wire. 151E can be prevented from dropping into the interior of the lower trunk 2a.

(Inspection method)
Next, a method for inspecting the steam generator 1 by the inspection device 100E of this embodiment will be described.
In the inspection method of this embodiment, an installation step of installing the guide member 140E, an insertion step of inserting the cable housing 150E along the guide member 140E into the inside of the lower shell 2a, and and an inspection step of inspecting the surface.
In the installation step, the first guide portion 141E of the guide member 140E extends from the hand holes 23, 24 located at the bottom of the lower trunk 2a toward the inside of the lower trunk 2a, and the tip of the second guide portion 142E The guide member 140E is installed so that the is arranged at a predetermined position inside the lower barrel 2a. The predetermined position at which the tip of the second guide portion 142E is arranged means that the cable accommodation body 150E extending from the tip of the second guide portion 142E is positioned so that it faces the portion of the heat transfer tube 32 to be inspected by the inspection probe 111. position to guide the

In the inserting step, the tip of the cable accommodation body 150E is advanced from the tip of the second guide portion 142E. Also, the amount of insertion of the cable containing body 150E into the interior of the lower shell 2a is adjusted so that the tip of the cable containing body 150E is arranged at a predetermined position inside the lower shell 2a. The predetermined position where the tip of the cable containing body 150E is arranged is the position within the lower shell 2a corresponding to the portion of the heat transfer tube 32 to be inspected by the inspection probe 111 .
In the inspection step, the inspection cable 110 guided by the guide member 140E and the cable housing body 150E is advanced from the tip of the cable housing body 150E, so that the heat transfer tube 32 located on the tip side of the cable housing body 150E is inspected by the inspection probe 111. inspect the outer surface of the

Next, two types of inspection examples of the inspection method by the inspection apparatus 100E of this embodiment will be described with reference to FIGS.

(First inspection example)
In the first inspection example shown in FIGS. 21 and 22, the outer surface of the heat transfer tube 32 on the lower surface side of the second tube support plate 33b is inspected. Therefore, in the installation step, the second guide portion 142E is bent upward at least with respect to the first guide portion 141E while the guide member 140E is inserted into the lower torso 2a through the second lower hand hole 24. The guide member 140E is arranged as shown. In addition, in the installation step, by rotating the first guide portion 141E about the longitudinal direction of the first guide portion 141E (horizontal direction X in FIGS. 21 and 22) as an axis, the bending direction of the second guide portion 142E is changed in the front-rear direction. Adjust to Y. Furthermore, in the installation step, the position of the second guide portion 142E in the left-right direction X is adjusted by moving the guide member 140E in the left-right direction X. As shown in FIG. As a result, in the insertion step, it is possible to adjust, in the front-rear direction Y and the left-right direction X, the region of the lower surface of the second tube support plate 33b reached by the tip of the cable accommodation body 150E extending from the tip of the second guide portion 142E. can be done.

After that, in the inspection step, the inspection probe 111 can reach a desired area on the lower surface of the second tube support plate 33b by advancing the inspection cable 110 from the tip of the cable housing 150E. As described above, the outer surfaces of all the heat transfer tubes 32 located on the lower surface side of the second tube support plate 33b can be inspected. In particular, even if the inspection cable 110 tends to hang down due to its own weight or the like, the area (the second tube support area) of the lower surface of the second tube support plate 33b that is away from both sides of the second lower hand hole 24 or the flow slot 36 in the front-rear direction Y The outer surface of the heat transfer tubes 32 located in the remaining area of the underside of the plate 33b) can be easily inspected.

(Second inspection example)
In the second inspection example shown in FIGS. 23 and 24, the outer surface of the heat transfer tube 32 located on the upper surface side of the flow distribution plate 34 is inspected.
Therefore, in the installation step, the guide member 140E is inserted into the lower barrel 2a through the second lower hand hole 24, and the second guide portion 142E is positioned at the opening of the flow distribution plate 34 with respect to the first guide portion 141E. The guide member 140E is arranged so as to curve upward toward 37. In addition, in the installation step, by rotating the first guide portion 141E around the longitudinal direction of the first guide portion 141E (horizontal direction X in FIGS. 23 and 24) as an axis, the bending direction of the second guide portion 142E is changed in the front-rear direction. Adjust to Y. Furthermore, in the installation step, the position of the second guide portion 142E in the left-right direction X is adjusted by moving the guide member 140E in the left-right direction X. As shown in FIG. As a result, in the insertion step, the front end of the cable accommodation body 150E extending from the front end of the second guide portion 142E moves the upper surface region of the flow distribution plate 34 through the opening 37 of the flow distribution plate 34 to It can be adjusted in the left-right direction X. Here, the area of the upper surface of the flow distribution plate 34 that the tip of the cable housing 150E can reach is the area located on both sides of the opening 37 in the front-rear direction Y, in other words, the area of the upper surface of the flow distribution plate 34 in the horizontal direction X corresponds to the opening 37 in .

After that, in the inspection step, the inspection probe 111 can reach a desired area on the upper surface of the flow distribution plate 34 by advancing the inspection cable 110 from the tip of the cable housing 150E. As described above, it is possible to inspect the outer surface of the heat transfer tube 32 located in the area corresponding to the opening 37 on the upper surface of the flow distribution plate 34 (the remaining area on the upper surface side of the flow distribution plate 34).

The inspection device 100E of the third embodiment can also be applied to inspection of the outer surface of the heat transfer tube 32 located on the lower surface side of the flow distribution plate 34, for example. In this case, in the installation step, the guide member 140E may be inserted from the first lower hand hole 23 into the lower barrel 2a in the same manner as in the second inspection example described above. Also, in the insertion step, the tip of the cable accommodation body 150E extending from the tip of the second guide portion 142E should be made to reach the lower surface of the second tube support plate 33b.

According to the inspection apparatus 100E and the inspection method according to the third embodiment, the same effects as those of the second embodiment are obtained.
Further, according to the inspection apparatus 100E according to the third embodiment, the inspection cable 110 can be inserted, and the first guide portion 141E of the guide member 140E and the first guide portion 141E that extends curvedly with respect to the first guide portion 141E. A cable accommodation body 150E is provided which is guided in order along the two guide parts 142E. The cable container 150E has a characteristic of being more easily bent than the guide member 140E and less likely to be bent than the inspection cable 110. As shown in FIG. Thereby, the inspection cable 110 can be linearly guided to a position away from the tip of the second guide portion 142E of the guide member 140E. That is, even if the tip portion of the inspection cable 110 tends to hang down due to its own weight or the like, the inspection probe 111 at the tip of the inspection cable 110 is linearly advanced to a desired position separated from the guide member 140E by the cable container 150E. be able to. Therefore, it becomes possible to efficiently inspect the outer surface of the heat transfer tube 32 over a wider range.

<Fourth embodiment>
Next, an inspection apparatus of a fourth embodiment for inspecting the steam generator 1 shown in FIGS. 1 to 3 will be described with reference to FIGS. 25 to 27. FIG.

(Inspection device)
As shown in FIG. 25, an inspection apparatus 100F of the fourth embodiment is an apparatus for inspecting the outer surfaces of a plurality of heat transfer tubes 32 accommodated in the lower shell 2a. and a cable accommodation body 150F. The configuration of the inspection cable 110 is the same as that of the inspection apparatus 100 of the first embodiment.

(Guide member)
The guide member 140F has a first guide portion 141F and a second guide portion 142F. The first guide portion 141F extends straight into the lower barrel 2a from the hand holes 23, 24 (the second lower hand hole 24 in FIG. 25) located in the lower portion of the lower barrel 2a. The second guide portion 142F extends from the tip of the first guide portion 141F while curving with respect to the first guide portion 141F. In addition, the second guide portion 142F is curved upward with respect to the first guide portion 141F while the first guide portion 141F extends in the horizontal direction (left-right direction X in FIG. 25). oriented and extends upwardly relative to the first guide portion 141F.

Furthermore, as shown in FIGS. 25 and 26, the second guide portion 142F extends upward and curves in a direction that is inclined with respect to one side of the upward direction and the front-rear direction Y. As shown in FIGS. As a result, the tip of the second guide portion 142F faces obliquely upward when viewed in the left-right direction X shown in FIG. In addition, the tip portion of the second guide portion 142F is rotatable with respect to the base end portion so that the tip of the second guide portion 142F can be selectively directed to either one side or the other side of the front-rear direction Y. It can be The inclination angle of the tip of the second guide portion 142F with respect to the upper direction or the front-rear direction Y may be adjustable or may be fixed.

The guide member 140F is formed in a tubular shape through which the inspection cable 110 and the cable container 150F can be inserted. The guide member 140F is a member that sequentially guides the inspection cable 110 to the first guide portion 141F and the second guide portion 142F via the cable container 150F, which will be described later. In other words, the guide member 140F is a member that guides the cable container 150F, into which the inspection cable 110 can be inserted, along the first guide portion 141F and the second guide portion 142F in order.

(cable container)
As shown in FIGS. 25 and 26, the cable container 150F extends in the longitudinal direction of the inspection cable 110 and has a tubular shape into which the inspection cable 110 can be inserted. As a result, the inspection probe 111 at the tip of the inspection cable 110 can be exposed or advanced from the tip of the cable container 150F.

Similar to the cable housing body 150F of the third embodiment, the cable housing body 150F has a characteristic of being more easily bent than the guide member 140F and a characteristic of being less likely to be bent than the inspection cable 110. FIG. Therefore, when the cable container 150F is guided along the first guide portion 141F and the second guide portion 142F of the guide member 140F in order, the cable container 150F is curved along the second guide portion 142F. In addition, the cable containing body 150F advanced from the tip of the second guide portion 142F can be moved upward in a straight line. Thereby, the inspection cable 110 can be linearly guided by the cable containing body 150F extending from the tip of the second guide portion 142F.
In this embodiment, as shown in FIG. 26, the tip of the second guide portion 142F faces obliquely upward when viewed in the left-right direction X, so that the cable container 150F extends diagonally upward from the tip of the second guide portion 142F. proceed as follows.

(Foreign matter recovery mechanism)
As shown in FIG. 25, the inspection apparatus 100F of this embodiment further includes a foreign matter recovery mechanism 160F that recovers foreign matter that has entered the lower trunk 2a. The foreign matter recovery mechanism 160</b>F recovers foreign matter found when the outer surface of the heat transfer tube 32 is inspected by the inspection probe 111 .
A foreign matter collecting mechanism 160F of the present embodiment includes a suction device 161F that sucks foreign matter. The suction device 161F includes a suction device 162F that generates a suction force, and a suction tube 163F that extends from the suction device 162F. The suction tube 163F is inserted into the cable container 150F together with the inspection cable 110. As shown in FIG. As shown in FIG. 27, the tip of the suction tube 163F is located at the tip of the cable container 150F together with the inspection probe 111 at the tip of the inspection cable 110. As shown in FIG.

(Inspection method)
Next, a method for inspecting the steam generator 1 by the inspection device 100F of this embodiment will be described.
In the inspection method of the present embodiment, an installation step of installing the guide member 140F, an insertion step of inserting the cable housing 150F along the guide member 140F into the inside of the lower shell 2a, and and an inspection step of inspecting the surface.
In the installation step, the first guide portion 141F of the guide member 140F extends toward the inside of the lower barrel 2a from the hand holes 23, 24 located at the bottom of the lower barrel 2a, and the tip of the second guide portion 142F The guide member 140F is installed so that the is placed at a predetermined position inside the lower barrel 2a. The predetermined position where the tip of the second guide part 142F is arranged means that the cable accommodation body 150F extending from the tip of the second guide part 142F is positioned so that the cable accommodation body 150F extends toward the portion of the heat transfer tube 32 to be inspected by the inspection probe 111. position to guide the

In the inspection method of this embodiment, the outer surface of the heat transfer tubes 32 on the lower surface side of the tube support plate 33c (hereinafter referred to as the third tube support plate 33c) adjacent to the upper side of the second tube support plate 33b is inspected. Therefore, in the installation step, as shown in FIG. 25, the guide member 140F is inserted into the lower barrel 2a through the second lower hand hole 24, and the second guide portion 142F is positioned above the first guide portion 141F. The guide member 140F is arranged so as to curve toward . Also, as shown in FIGS. 25 and 26, the tip portion of the second guide portion 142F extending upward from the first guide portion 141F is passed through the flow slot 36 of the second tube support plate 33b to It is made to reach the upper surface side of the support plate 33b. The position of the tip portion of the second guide portion 142F can be set by changing the length of the second guide portion 142F in the vertical direction Z. In addition, the position of the tip of the second guide portion 142F in the left-right direction X can be set by changing the length of the first guide portion 141F inserted into the lower trunk 2a in the left-right direction X. The tip of the second guide portion 142F located on the upper surface side of the second tube support plate 33b is inclined with respect to one side of the upper surface side of the second tube support plate 33b and the front-rear direction Y (that is, obliquely upward). suitable for

In the inserting step, the cable accommodation body 150F is advanced from the tip of the second guide portion 142F. Also, the amount of insertion of the cable containing body 150F into the interior of the lower shell 2a is adjusted so that the tip of the cable containing body 150F is arranged at a predetermined position inside the lower shell 2a. In this embodiment, the predetermined position where the tip of the cable containing body 150F is arranged is the position on the lower surface side of the third tube support plate 33c.
Specifically, the cable accommodation body 150F advanced from the tip of the second guide portion 142F advances in a straight line obliquely upward so as to face one side in the front-rear direction Y as it goes upward. As a result, the tip of the cable accommodation body 150F is located in the area on one side of the flow slot 36 of the third tube support plate 33c in the front-rear direction Y on the lower surface of the third tube support plate 33c.

In the inspection step, the inspection cable 110 guided by the guide member 140F and the cable housing body 150F is advanced from the tip of the cable housing body 150F, so that the heat transfer tube 32 located on the tip side of the cable housing body 150F is inspected by the inspection probe 111. inspect the outer surface of the In this embodiment, the outer surface of the heat transfer tubes 32 arranged in the region of the lower surface side of the third tube support plate 33c located on one side of the flow slot 36 of the third tube support plate 33c in the front-rear direction Y is inspected. .
In the installation step, by appropriately adjusting or changing the direction in which the tip of the second guide part 142F faces and the position of the tip of the second guide part 142F in the left-right direction X, in the inspection step, the third tube support plate 33c It is possible to inspect the outer surface of all the heat transfer tubes 32 located on the lower surface side of the .

In the inspection method of the present embodiment, when foreign matter is found by the inspection probe 111 in the inspection step, a foreign matter recovery step may be performed in which the foreign matter is recovered by the foreign matter recovery mechanism 160F.

According to the inspection apparatus 100F and the inspection method according to the fourth embodiment, the same effects as those of the third embodiment can be obtained.

In the fourth embodiment, the foreign matter collecting mechanism 160F is not limited to the suction device 161F that sucks foreign matter, and may include a gripping device that grips foreign matter, an electromagnet that magnetically attracts foreign matter, and the like. Also, the foreign matter collecting mechanism 160F of the fourth embodiment may be applied to, for example, the inspection apparatuses of the first to third embodiments.

As described above, each embodiment of the present disclosure has been described in detail with reference to the drawings, but the specific configuration is not limited to these embodiments, and includes design changes etc. that do not deviate from the gist of the present disclosure. be

<Appendix>
For example, the method of reinforcing a steam generator and the steam generator described in each embodiment are grasped as follows.

(1) A steam generator inspection apparatus according to a first aspect includes a vertically extending heat transfer tube inside a vertically extending body, and supporting the heat transfer tube with respect to the body. and a tube support plate having a flow slot through which a medium flowing inside the body can pass in a vertical direction. and an inspection cable having an inspection probe for inspecting the outer surface of the heat transfer tube at its tip, and holding the inspection cable movably in its longitudinal direction, using the heat transfer tube as a guide in the vertical direction and a holding guide mechanism that is movable through the flow slots of the tube support plate; and a lifting mechanism that moves the holding guide mechanism vertically.

In the above configuration, the holding guide mechanism that holds the inspection cable can be moved in the vertical direction of the body by the elevating mechanism so as to pass through the flow slot of the tube support plate. Thereby, even if the inside of the barrel is vertically partitioned by the tube support plate, it is possible to prevent the tube support plate from restricting the accessible range of the inspection probe. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube over a wide range.

Further, the holding guide mechanism is vertically movable using the heat transfer tube as a guide. As a result, the holding guide mechanism can be stably moved in the vertical direction at a desired position within the barrel. Thereby, the inspection of the outer surface of the heat transfer tube by the inspection probe can be performed in a stable state.

(2) In the steam generator inspection apparatus according to the second aspect, the holding guide mechanism includes a guide body that can pass through the flow slot in the vertical direction and the guide body in the first orthogonal direction orthogonal to the vertical direction. a pair of guide legs movably provided between a deployment position extending from the main body in opposite directions and a storage position stored inside the guide body, the pair of guide legs being in the deployment position; In the arranged state, the pair of guide legs contact the two heat transfer tubes positioned on both sides of the guide body in the first orthogonal direction, so that the holding guide mechanism guides the two heat transfer tubes. , it becomes possible to move up and down.

According to the above configuration, when the pair of guide legs are arranged in the unfolded position, they are in contact with the two heat transfer tubes located on both sides of the guide body, so that the heat transfer tubes are used as guides to reliably move the holding guide mechanism in the vertical direction. can be moved to Moreover, since the holding guide mechanism can be sandwiched between the two heat transfer tubes when the pair of guide legs are arranged in the deployed position, the posture of the holding guide mechanism can be reliably stabilized. Thereby, the inspection of the outer surface of the heat transfer tube by the inspection probe can be performed in a stable state.
Further, by arranging the pair of guide legs in the retracted position, it is possible to prevent the pair of guide legs from obstructing passage of the holding guide mechanism through the flow slot.

(3) In the steam generator inspection device according to the third aspect, a plurality of pairs of the guide legs are arranged in the vertical direction of the guide main body.

According to the above configuration, when the holding guide mechanism is passed through the flow slot of the tube support plate, even if the predetermined pair of guide legs are arranged in the storage position inside the flow slot of the tube support plate, the tube support plate will not move. Another pair of guide legs located above or below the can be placed in the deployed position. As a result, the posture of the holding guide mechanism can be stabilized even when the holding guide mechanism is passed through the flow slot.

(4) In the steam generator inspection apparatus according to the fourth aspect, the holding guide mechanism includes a holding portion that holds the inspection cable movably in its longitudinal direction, a vertical direction and the first orthogonal direction. and a moving mechanism for moving the holding part toward or away from the guide body in a second orthogonal direction orthogonal to the direction of the guide body.

According to the above configuration, the holding part and the inspection cable held by the holding part can be moved in the second orthogonal direction with respect to the guide body by the moving mechanism. Thereby, even if the guide body is held at a predetermined position in the second orthogonal direction, it is possible to inspect the outer surface of the heat transfer tube within a predetermined range in the second orthogonal direction with the inspection probe. This makes it possible to efficiently inspect the outer surface of the heat transfer tube over a wide range.

(5) A steam generator inspection method according to a fifth aspect is a steam generator inspection method using the inspection device, wherein the lifting mechanism guides the holding guide mechanism to a predetermined region in the vertical direction. and an inspection step of inspecting the outer surface of the heat transfer tube with the inspection probe in the predetermined area.

According to the inspection method described above, the holding guide mechanism can be moved in the vertical direction of the body by the elevating mechanism to pass through the flow slot of the tube support plate. Thereby, even if the inside of the barrel is vertically partitioned by the tube support plate, it is possible to prevent the tube support plate from restricting the accessible range of the inspection probe. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube over a wide range.

(6) A steam generator inspection apparatus according to a sixth aspect includes a vertically extending heat transfer tube inside a vertically extending body, and supporting the heat transfer tube with respect to the body. and a tube support plate having a flow slot through which a medium flowing inside the body can pass in a vertical direction, wherein a hand hole located at a lower portion of the body is used to inspect the interior of the body. and an inspection cable having an inspection probe for inspecting the outer surface of the heat transfer tube at its tip; and a second guide portion curvedly extending from the tip of the first guide portion with respect to the first guide portion, wherein the inspection cable is passed through the first guide portion and the second guide portion in order. and a guide member for guiding along.

According to the above configuration, the inspection cable is inserted into the interior of the body through the hand hole located at the bottom of the body and is guided along the first guide portion and the second guide portion of the guide member in order. By doing so, the inspection probe at the tip of the inspection cable can be advanced in a direction different from the direction in which the first guide portion extends, that is, in a desired direction inside the trunk. Therefore, it is possible to efficiently inspect the outer surface of the heat transfer tube over a wide range.

(7) In the steam generator inspection device according to the seventh aspect, the second guide portion is directed upward by being curved with respect to the first guide portion.

According to the above configuration, it is possible to inspect the outer surface of the heat transfer tube positioned above the hand hole in the lower part of the body with the inspection probe.

(8) In the steam generator inspection apparatus according to the eighth aspect, the second guide portion extends upward with respect to the first guide portion, passes through the flow slot, and is located on the upper surface side of the tube support plate. to reach

According to the above configuration, it is possible to inspect the outer surface of the heat transfer tube with the inspection probe on the upper surface side of the tube support plate located above the hand hole in the lower part of the body.

(9) In the steam generator inspection apparatus according to the ninth aspect, the second guide portion is curved in a direction crossing the vertical direction on the upper surface side of the tube support plate.

According to the above configuration, the inspection probe at the tip of the inspection cable can be advanced in the direction along the upper surface of the tube support plate located above the hand hole in the lower part of the body. . This makes it possible to efficiently inspect the outer surface of the heat transfer tube over a wide range.

(10) The steam generator inspection device according to the tenth aspect extends in the longitudinal direction of the inspection cable, is formed in a shape into which the inspection cable can be inserted, and is curved more than the guide member. and a cable container that is more difficult to bend than the inspection cable, and that is guided from a hand hole located below to the first guide portion and the second guide portion in order. Prepare.

According to the above configuration, the cable container can linearly guide the inspection cable to a position away from the guide member (the tip of the second guide portion). That is, even if the tip portion of the inspection cable tends to hang down due to its own weight or the like, the inspection probe at the tip of the inspection cable can be linearly advanced to a desired position separated from the guide member by the cable container. Therefore, it becomes possible to efficiently inspect the outer surface of the heat transfer tube over a wider range.

(11) A steam generator inspection method according to an eleventh aspect is a steam generator inspection method using the inspection device, in which the first guide portion extends from a hand hole located below the body portion to the body portion. an installation step of installing the guide member so as to extend toward the inside of the body and such that the tip of the second guide portion is arranged at a predetermined position inside the body; and an inspection step of advancing the inspection cable from the tip of the second guide portion and inspecting the outer surface of the heat transfer tube with the inspection probe.

According to the above inspection method, in the installation step, the tip of the second guide portion of the guide member can be arranged at a predetermined position inside the body. Thereby, in the inspection step, the end of the inspection cable (inspection probe) is inserted into the inside of the body through the hand hole located in the lower part of the body and guided by the first guide portion and the second guide portion of the guide member. ) can be advanced from the tip of the second guide portion into the interior of the body portion to inspect the outer surface of the heat transfer tube at a predetermined position and its surroundings.

1 steam generator 2 body 23, 24, 25 hand hole 32 heat transfer tube 33 tube support plate 36 flow slots 100, 100A, 100B, 100C, 100D, 100E, 100F inspection device 120 holding guide mechanism 121 guide body 122 guide leg 123 Holding portion 124 Moving mechanism 130 Lifting mechanism 140, 140A, 140B, 140C, 140D, 140E, 140F Guide member 141, 141A, 141B, 141C, 141D, 141E, 141F First guide portion 142, 142A, 142B, 142C, 142D, 142E, 142F Second guide parts 150E, 150F Cable container P1 Unfolded position P2 of guide leg 122 Storage position X of guide leg 122 Horizontal direction (second orthogonal direction)
Y front-back direction (first orthogonal direction)
Z vertical direction

Claims (11)

Inside the body extending in the vertical direction, there are provided heat transfer tubes extending in the vertical direction, and flow slots that support the heat transfer tubes with respect to the body and allow the medium flowing inside the body to pass in the vertical direction. A steam generator inspection device comprising a tube support plate,
an inspection cable which is inserted into the body through a hand hole located at the bottom of the body and has an inspection probe at its tip for inspecting the outer surface of the heat transfer tube;
a holding guide mechanism that holds the inspection cable movably in its longitudinal direction, is movable vertically using the heat transfer tube as a guide, and can pass through the flow slot of the tube support plate;
an elevating mechanism that vertically moves the holding guide mechanism;
A steam generator inspection device comprising: The holding guide mechanism is
a guide body that can pass through the flow slot in the vertical direction;
a pair of guide legs movably provided between a deployed position extending in opposite directions from the guide body in a first orthogonal direction orthogonal to the vertical direction and a retracted position stored inside the guide body; , and
When the pair of guide legs are arranged in the deployed position, the pair of guide legs contact the two heat transfer tubes located on both sides of the guide main body in the first orthogonal direction, so that the holding guide 2. The apparatus for inspecting a steam generator according to claim 1, wherein the mechanism is vertically movable using the two heat transfer tubes as guides. 3. The steam generator inspection device according to claim 2, wherein a plurality of pairs of said pair of guide legs are arranged in a vertical direction of said guide body. The holding guide mechanism is
a holding part that holds the inspection cable movably in its longitudinal direction;
and a moving mechanism for moving the holding part toward or away from the guide body in a vertical direction and a second orthogonal direction orthogonal to the first orthogonal direction. The steam generator inspection device according to 1. A steam generator inspection method using the inspection device according to any one of claims 1 to 4,
a guiding step for guiding the holding guide mechanism to a predetermined area in the vertical direction by the lifting mechanism;
and an inspection step of inspecting the outer surface of the heat transfer tube with the inspection probe in the predetermined area. Inside the body extending in the vertical direction, there are provided heat transfer tubes extending in the vertical direction, and flow slots that support the heat transfer tubes with respect to the body and allow the medium flowing inside the body to pass in the vertical direction. A steam generator inspection device comprising a tube support plate,
an inspection cable which is inserted into the body through a hand hole located at the bottom of the body and has an inspection probe at its tip for inspecting the outer surface of the heat transfer tube;
A first guide section extending toward the inside of the body section from a hand hole positioned at the bottom of the body section, and a second guide section extending from a tip of the first guide section curvedly with respect to the first guide section. a guide member having portions for guiding the inspection cable to the first guide portion and the second guide portion in order;
A steam generator inspection device comprising: 7. The steam generator inspection device according to claim 6, wherein the second guide portion is directed upward by being curved with respect to the first guide portion. 8. The apparatus for inspecting a steam generator according to claim 7, wherein the second guide portion extends upwardly with respect to the first guide portion and passes through the flow slot to reach the upper surface side of the tube support plate. 9. The steam generator inspection device according to claim 8, wherein the second guide portion is curved in a direction crossing the vertical direction on the upper surface side of the tube support plate. It extends in the longitudinal direction of the inspection cable, is formed into a shape into which the inspection cable can be inserted, and has characteristics of being more easily bent than the guide member and less likely to be bent than the inspection cable. 10. The steam according to any one of claims 6 to 9, further comprising a cable housing that is guided from a hand hole located at the bottom to the first guide portion and the second guide portion in order. Generator inspection device. A steam generator inspection method using the inspection device according to any one of claims 6 to 10,
The tip of the second guide portion is arranged at a predetermined position inside the trunk portion so that the first guide portion extends toward the inside of the trunk portion from a hand hole located in the lower portion of the trunk portion. an installation step of installing the guide member such that
and an inspection step of inspecting the outer surface of the heat transfer tube with the inspection probe by advancing the inspection cable guided by the guide member from the tip of the second guide portion.

Images