Work equipment and work methods

Abstract

To perform work suitable for an object in a steam generator.SOLUTION: A working device for a steam generator comprising a heat transfer tube inside a drum part comprises: a hollow cable housing body capable of being inserted into a hand hole formed in the drum part, and extending in an axial direction; a hollow nozzle provided at a tip of the cable housing body, and in which a first opening part and a second opening part are formed in a tip part; a working tool comprising a cable inserted into the housing body and the nozzle, and a working part provided at a tip of the cable, and exposed from the first opening part; and a camera tool comprising a cable inserted into the cable housing body and the nozzle, and a camera provided at a tip of the cable, and exposed from the second opening part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to work equipment and work methods. [Background technology]

[0002] Nuclear power facilities often have steam generators. Patent Document 1 shows an inspection device for a steam generator. This inspection device inspects the inside of the steam generator by inserting and hanging an inspection probe from a hand hole provided on the side of the upper part of the body of the steam generator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-173468 Summary of the Invention [Problem to be solved by the invention]

[0004] In this case, foreign matter such as scale may be generated inside the steam generator, and therefore, when foreign matter is generated, it is necessary to take appropriate action, such as removing or collecting the foreign matter from inside the steam generator.

[0005] An object of the present disclosure is to provide a work device and a work method that enable appropriate work to be performed on foreign matter inside a steam generator. [Means for solving the problem]

[0006] The work equipment disclosed herein is a work equipment for a steam generator having a heat transfer tube inside a body, and includes: a hollow cable housing that can be inserted into a hand hole formed in the body and extends in the axial direction; a hollow nozzle that is provided at the tip of the cable housing and has a first opening and a second opening at the tip; a work tool that has a cable that is inserted into the cable housing and the nozzle, and a working part that is provided at the tip of the cable and exposed from the first opening; and a camera tool that has a cable that is inserted into the cable housing and the nozzle, and a camera that is provided at the tip of the cable and exposed from the second opening.

[0007] The work method according to the present disclosure is a work method using the work equipment, and includes the steps of inserting the cable housing into the steam generator through the hand hole, advancing the camera of the camera tool out of the nozzle through the second opening of the nozzle, and advancing the working part of the work tool out of the nozzle through the first opening of the nozzle. [Effects of the Invention]

[0008] According to the present disclosure, appropriate work can be performed on foreign matter inside a steam generator. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is an explanatory diagram showing the configuration of a steam generator. [Figure 2] FIG. 2 is a schematic diagram of a work implement according to an embodiment. [Figure 3] FIG. 3 is an explanatory diagram for explaining the work equipment. [Figure 4] FIG. 4 is a cross-sectional view of the cable housing. [Figure 5] FIG. 5 is an explanatory diagram for explaining the nozzle. [Figure 6] FIG. 6 is a schematic diagram of the camera tool. [Figure 7] FIG. 7 is a schematic diagram of a retrieval tool. [Figure 8] FIG. 8 is a schematic diagram of a cleaning tool. [Figure 9] FIG. 9 is a flowchart showing the procedure of the operation method. [Figure 10] FIG. 10 is a schematic diagram for explaining the operation method. [Figure 11] FIG. 11 is a schematic diagram for explaining the operation method. [Figure 12] FIG. 12 is a schematic diagram for explaining the operation method. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Note that the present disclosure is not limited to these embodiments, and when there are multiple embodiments, the present disclosure also includes configurations in which the respective embodiments are combined.

[0011] <Steam generator> FIG. 1 is an explanatory diagram showing the configuration of a steam generator. The steam generator 100 is a heat exchanger used in nuclear facilities. Primary cooling water that has reached a high temperature in the reactor pressure vessel and secondary cooling water that flows on the turbine side flow through the steam generator 100. The steam generator 100 exchanges heat between the primary cooling water and the secondary cooling water, and generates steam by evaporating the secondary cooling water.

[0012] The steam generator 100 is disposed in the vertical direction and has a body portion 102. The body portion 102 has a hollow cylindrical shape. A heat transfer tube group 104 is provided within the body portion 102. The heat transfer tube group 104 is composed of a plurality of heat transfer tubes 104A each having an inverted U-shape. The heat transfer tubes 104A are disposed so that the arc portion of the inverted U-shape at the top is convex upward. The lower ends of the heat transfer tubes 104A are supported by a tube plate 106, and their middle portions are supported by the body portion 102 via a plurality of tube support plates 108. The tube support plates 108 have a large number of through-holes through which the heat transfer tubes 104A are inserted. The tube support plates 108 are disposed at approximately equal intervals in the vertical direction. The tube support plates 108 are provided with flow slots 108A through which a fluid flowing within the body portion 102, described below, passes.

[0013] The body 102 has a water chamber 110 at its lower end. The water chamber 110 is bowl-shaped, and the interior is divided into an inlet-side water chamber 114 and an outlet-side water chamber 116 by a partition plate 112. One end of the heat transfer tube 104A is connected to the inlet-side water chamber 114, and the other end of the heat transfer tube 104A is connected to the outlet-side water chamber 116. The inlet-side water chamber 114 is formed with an inlet-side nozzle 114A that communicates with the outside of the body 102, and the outlet-side water chamber 116 is formed with an outlet-side nozzle 116A that communicates with the outside of the body 102. A primary cooling water pipe (not shown) from the pressurized water reactor is connected to the inlet-side nozzle 114A, and a primary cooling water pipe (not shown) that sends primary cooling water after heat exchange to the pressurized water reactor is connected to the outlet-side nozzle 116A.

[0014] The upper half of the body 102 is provided with a steam-water separator 118 that separates feedwater into steam and hot water, and a moisture separator 120 that removes moisture from the separated steam to produce a state close to dry steam. A water supply pipe 122 that supplies secondary cooling water from the outside into the body 102 is inserted between the steam-water separator 118 and the heat transfer tube bank 104. The body 102 also has a steam outlet 124 at its upper end. The lower half of the body 102 is also provided with a water supply passage 128 that allows the secondary cooling water supplied from the water supply pipe 122 into the body 102 to flow downward between the body 102 and a tube bank outer casing 126, turn back at the tube sheet 106, and rise along the heat transfer tube bank 104. The steam outlet 124 is connected to a secondary cooling water pipe (not shown) that sends steam to the turbine, and the water supply pipe 122 is connected to a secondary cooling water pipe (not shown) that supplies secondary cooling water that has been cooled in a condenser (not shown) from steam used in the turbine.

[0015] The trunk portion 102 is provided with hand holes H that communicate between the inside and outside thereof. The hand holes H are provided, for example, on the side surfaces of the upper and lower halves of the trunk portion 102, and in this embodiment, are provided at the position of the lowest tube support plate 108 and the position of the second-highest tube support plate 108. The hand holes H are also provided so as to penetrate the tube bank outer casing 126, and are configured to allow access to the tube support plates 108 from the outside of the trunk portion 102. Note that the hand holes H are closed with lids attached when the steam generator 100 is in use. The hand holes H are provided on both sides of the trunk portion 102 so as to pass through the center of the inverted U-shape of the heat transfer tube 104A and face each other.

[0016] <Work equipment> The work implement 10 according to this embodiment will be described with reference to Fig. 2 to Fig. 6. Fig. 2 is a schematic diagram showing the work implement according to the embodiment. Fig. 3 is an explanatory diagram for explaining the work implement. Fig. 4 is a cross-sectional view of a cable housing. Fig. 5 is an explanatory diagram for explaining a nozzle. Fig. 6 is a schematic diagram of a camera tool.

[0017] The work equipment 10 has a guide tray 11, a cable housing 12, a nozzle 14, a fixed tool 16, a work tool 30, and a camera tool 60. The work equipment 10 is equipment that performs work on foreign matter that has occurred in the steam generator 100. In this embodiment, the foreign matter is scale S that contains iron components, and is located on the tube support plate 108. However, the foreign matter that is the target of the work equipment 10 is not limited to scale, and may be any object. The work equipment 10 collects the scale S by using a collection tool 40 as the work tool 30, and washes away the scale S on the tube support plate 108 with cleaning liquid by using a cleaning tool 50 as the work tool 30.

[0018] (Information tray) As shown in FIG. 2, the guide tray 11 is a guide member for guiding the cable housing 12 into the body portion 102. The guide tray 11 is attached to the hand hole H via a guide tray attachment member (not shown). The guide tray 11 extends from the hand hole H toward the inside of the body portion 102. This allows the cable housing 12 to be introduced from the outside to the inside of the body portion 102 along the guide tray 11 through the hand hole H.

[0019] The guide tray 11 is configured to be able to guide the cable housing 12 so that it does not shift laterally relative to the insertion direction when the cable housing 12, which is the object to be guided, is introduced from the outside to the inside of the body 102. For example, the guide tray 11 has a substantially concave cross-sectional shape that corresponds to the outer contour of the cable housing 12 in a cross section perpendicular to the extension direction, thereby preventing the cable housing 12 from shifting laterally relative to the insertion direction.

[0020] The tip 11A of the guide tray 11 is open, and the cable housing 12 that has been guided to the tip 11A by the guide tray 11 can be exposed from the tip 11A. In this embodiment, the guide tray 11 extends straight from the hand hole H to the vicinity of the tip 11A, and the tip 11A faces downward. As a result, the portion of the cable housing 12 that is exposed from the tip 11A of the cable housing 12 guided by the guide tray 11 smoothly deforms downward due to its own weight.

[0021] In this embodiment, the tip portion 11A is curved downward, so that when the cable housing body 12 is fed while deforming downward at the tip portion 11A, it can deform smoothly without clogging the guide tray 11. This makes it possible to efficiently avoid problems such as the cable housing body 12 getting stuck near the tip portion 11A.

[0022] The guide tray 11 having the above configuration is configured so that the length from the hand hole H to the tip end 11A (the insertion length into the body 102) is variable. For example, the guide tray 11 is fixed to the hand hole H via a fixing structure (not shown), but the length from the hand hole H to the tip end 11A can be changed by making the fixing position of the guide tray 11 relative to the fixing structure variable. Furthermore, if the fixing structure includes a feed mechanism (not shown) for adjusting the insertion amount of the guide tray 11 from the hand hole H, the length from the hand hole H to the tip end 11A can be changed by operating the feed mechanism while the guide tray 11 is fixed to the hand hole H.

[0023] (cable housing) As shown in FIGS. 2 to 4 , the cable housing 12 is an axial member extending in the extension direction (axial direction). The cable housing 12 is insertable into a hand hole H and is inserted into the interior of the steam generator 100 from the hand hole H. The cable housing 12 can be fed out of the guide tray 11 from a feeding device 13 connected to an end of the guide tray 11 on the outside of the body 102, and is thereby fed out from the hand hole H into the interior of the steam generator 100. Specifically, by rotating a handle 13A of the feeding device 13, the cable housing 12 wound around a reel 13B can be fed into the interior of the steam generator 100. When the cable housing 12 is inserted into the interior of the steam generator 100, the portion exposed from the tip end 11A of the guide tray 11 deforms downward due to its own weight. However, the method of inserting the cable housing 12 into the interior of the steam generator 100 from the hand hole H is not limited to this and may be any method. For example, the guide tray 11 and the delivery device 13 are not essential components.

[0024] The cable housing 12 is hollow, and has a space formed therein through which the fixing tool 16, the work tool 30, the camera tool 60, etc. are inserted. The cable housing 12 includes divided bodies 12A that are connected to one another along the extension direction of the cable housing 12. The connection angle between adjacent divided bodies 12A is variable, and the cable housing 12 deforms downward due to its own weight. As shown in FIG. 4, the cable housing 12 is formed with an insertion hole 12B through which the work tool 30 is inserted, an insertion hole 12C through which the camera tool 60 is inserted, and an insertion hole 12D through which the fixing tool 16 is inserted.

[0025] The cable housing 12 is configured to be able to pass through the flow slots 108A provided in each of the tube support plates 108. The tube support plates 108 are provided with a plurality of flow slots 108A that are opened to allow the medium flowing inside the trunk portion 102 to pass through. The flow slots 108A are elongated openings that extend along the arrangement direction of the heat transfer tubes 104A near the heat transfer tubes 104A supported by the tube support plates 108. The cable housing 12 is configured to be smaller than the flow slots 108A, and therefore can access the lower part of the trunk portion 102 by passing through the flow slots 108A of the plurality of tube support plates 108.

[0026] (nozzle) 3 and 5, the nozzle 14 is a hollow member provided at the tip of the cable housing 12. The internal space of the nozzle 14 is in communication with the internal space of the cable housing 12. The nozzle 14 is made of, for example, metal, and guides the work tool 30, camera tool 60, and fixing tool 16 that are inserted through the cable housing 12. In this embodiment, the nozzle 14 is fixed to the tip of the cable housing 12 with a bolt, but the method of fixing the nozzle 14 to the cable housing 12 may be arbitrary.

[0027] The nozzle 14 has a curved shape extending from the base end 14T1 to the tip end 14T2. In the example of FIG. 5, the nozzle 14 extends straight from the base end 14T1 to a midpoint between the base end 14T1 and the tip end 14T2, and then curves relative to the extension direction from the base end 14T1 to the midpoint as it extends from the midpoint to the tip end 14T2. In other words, the central axis of the nozzle 14 extending from the base end 14T1 to the tip end 14T2 includes a curved portion. The central axis of the nozzle 14 is linear from the base end 14T1 to the midpoint, and curved from the midpoint to the tip end 14T2. This curvature of the nozzle 14 allows the work tool 30 and the camera tool 60 to be appropriately inserted between the heat transfer tubes 104A. However, the shape of the nozzle 14 is not limited to the above description and may be any shape.

[0028] The nozzle 14 has a base end 14T1 connected to the tip of the cable housing 12, and a first opening 14A and a second opening 14B formed in the tip end 14T2. As will be described in detail later, the work tool 30 is led out from the first opening 14A, and the camera tool 60 is led out from the second opening 14B. More specifically, the nozzle 14 has a first space 14A1 and a second space 14B1 formed therein. The first space 14A1 is a space formed within the nozzle 14 that opens to the base end 14T1 side and the tip end 14T2 side. The opening of the first space 14A1 on the tip end 14T2 side is the first opening 14A. The second space 14B1 is a space formed within the nozzle 14 that opens to the base end 14T1 side and the tip end 14T2 side of the nozzle 14. The opening of the second space 14B1 on the tip end 14T2 side is the second opening 14B. The first space 14A1 and the second space 14B1 are separated by a wall 14D. In this embodiment, the nozzle 14 is positioned so that the extension direction from the base end 14T1 to the intermediate position faces vertically downward. In the curved section from the intermediate position to the tip end 14T2, the first space 14A1 is positioned vertically lower than the second space 14B1 (the first opening 14A is positioned vertically lower than the second opening 14B). This reduces the degree of curvature of the second space 14B1, allowing for easy insertion of the camera tool 60. That is, the degree of curvature is the length of the bend relative to the overall length of the nozzle 14. By positioning the second opening 14B vertically higher than the first opening 14A, the second space 14B1 becomes shorter than the first space 14A1. This allows for easy insertion of the camera tool 60. In this manner, in the present embodiment, the first space 14A1 in which the first opening 14A is formed and the second space 14B1 in which the second opening 14B is formed are isolated within the nozzle 14. However, this is not limiting, and the space in which the first opening 14A is formed and the space in which the second opening 14B is formed may be one unisolated space.

[0029] The nozzle 14 also has a third opening 14C. As will be described in detail later, the fixed tool 16 is led out through the third opening 14C. While the third opening 14C may be formed at any position, in this embodiment, it is formed between the base end 14T1 and the tip end 14T2 in the extension direction of the nozzle 14. More specifically, it is formed in the curved section between the intermediate position and the tip end 14T2. Furthermore, in this embodiment, the third opening 14C is formed to open vertically downward when the nozzle 14 is positioned so that the extension direction from the base end 14T1 to the intermediate position faces vertically downward. This allows the fixed tool 16 to be drawn vertically downward. In this embodiment, the third opening 14C is connected to the first space 14A1, but this is not limiting. For example, a third space isolated from the first space 14A1 and the second opening 14B may be formed in the nozzle 14, and the third opening 14C may be connected to this third space. It should be noted that the third opening 14C does not need to be formed, for example, when the fixing tool 16 is not provided.

[0030] The nozzle 14 is also formed with a support member 20 that supports the fixed tool 16 extending from the third opening 14C. The support member 20 is shaped to protrude outward from the nozzle 14 from a position near the third opening 14C (for example, within a predetermined distance from the third opening 14C). In this embodiment, the support member 20 extends vertically downward when the nozzle 14 is positioned so that the extension direction from the base end 14T1 to the intermediate position faces vertically downward. However, the support member 20 is not an essential component.

[0031] (fixed tool) The fixing tool 16 has a cable that is inserted into the cable housing 12 and the nozzle 14, and a fixing portion that is provided at the tip of the cable, exposed from the third opening 14C, and fixed to the steam generator 100. The fixing tool 16 fixes the position of the nozzle 14 relative to the steam generator 100 by fixing the fixing portion to the steam generator 100. In this embodiment, as shown in FIG. 3 , the fixing tool 16 includes a balloon 18 as the fixing portion, and a gas supply pipe 22 as the cable.

[0032] As shown in FIG. 3, balloon 18 is made of, for example, a stretchable elastic material (e.g., rubber). Balloon 18 is provided with opening 18A. When gas is supplied to the interior of balloon 18 through opening 18A, balloon 18 increases in volume and expands, and when the gas inside is discharged through opening 18A, balloon 18 decreases in volume and contracts. The shape of balloon 18 when expanded may be any shape, including, for example, a sphere, a cylinder (column), a rectangular parallelepiped, or other three-dimensional shape. The gas supplied to balloon 18 is preferably, for example, air or an inert gas (e.g., nitrogen).

[0033] The gas supply pipe 22 is a pipe that conducts gas inside. The gas supply pipe 22 is preferably flexible and may be made of, for example, a resin material (e.g., nylon, Teflon (registered trademark), urethane, etc.). The tip of the gas supply pipe 22 is connected to the opening 18A of the balloon 18.

[0034] In the present embodiment, the gas supply pipe 22 is inserted through the cable housing 12 and the nozzle 14, and the balloon 18, whose tip is provided at the tip of the gas supply pipe 22, is exposed to the outside of the nozzle 14 through the third opening 14C of the nozzle 14. Furthermore, in the present embodiment, a portion of the gas supply pipe 22, including the tip, is exposed to the outside of the nozzle 14, and the exposed portion of the gas supply pipe 22 is fixed to the support member 20. The gas supply pipe 22 may be fixed to the support member 20 by any method, and may be fixed, for example, by tape.

[0035] (Camera Tool) As shown in FIGS. 3 and 6 , the camera tool 60 includes a cable 61 and a camera 65 attached to the distal end of the cable 61. The camera tool 60 is a so-called endoscope, such as a fiberscope. The camera 65 is an imaging unit capable of capturing images of the external environment and includes an imaging element such as a charge-coupled device (CCD) and an illumination element such as an LED (light-emitting diode). The cable 61 includes a power supply cable to the imaging element and the illumination element and a signal cable for transmitting an image signal from the imaging element. The distal end of the cable 61 may be bendable and may include a control wire therein for controlling the bending. For this reason, the proximal end of the cable 61 may be connected to an operation unit 62 for operating the control wire. The camera tool 60 may also include an image processing unit 63 and a display unit 64. The image processing unit 63 is connected to the proximal end of the cable 61 and supplies power to the imaging element and the illumination element, and processes an image signal from the imaging element into a captured image signal for display. The display means 64 is connected to the image processing means 63, and receives the captured image signal to display the captured image.

[0036] In the present embodiment, the camera tool 60 has a cable 61 inserted through the cable housing 12 and the nozzle 14, and a camera 65 provided at the tip of the cable 61 exposed to the outside of the nozzle 14 through the second opening 14B of the nozzle 14. More specifically, the cable 61 passes through the cable housing 12 and is inserted into the second space 14B1 of the nozzle 14, and the camera 65 is exposed from the second space 14B1 to the outside of the nozzle 14 through the second opening 14B.

[0037] (Work Tools) The work tool 30 includes a cable and a working part provided at the tip of the cable. The cable of the work tool 30 is inserted into the cable housing 12 and the nozzle 14, and the working part is exposed to the outside of the nozzle 14 from the first opening 14A of the nozzle 14. More specifically, the cable of the work tool 30 passes through the cable housing 12 and is inserted into the first space 14A1 of the nozzle 14, and the working part is exposed from the first space 14A1 to the outside of the nozzle 14 through the first opening 14A. The working part of the work tool 30 is a tool for performing work on the scale S.

[0038] The work tool 30 will be described using Figures 7 and 8. Figure 7 is a schematic diagram of a collection tool. Figure 8 is a schematic diagram of a cleaning tool. The work tool 30 includes a collection tool 40 shown in Figure 7 and a cleaning tool 50 shown in Figure 8. That is, when collecting scale S, the collection tool 40 is used as the work tool 30, and when removing the scale S by cleaning, the cleaning tool 50 is used as the work tool 30. Note that in this embodiment, the collection tool 40 and the cleaning tool 50 are not inserted into the nozzle 14 at the same time.

[0039] (Collection tool) 7, the retrieval tool 40 has an electromagnet 42 as a working part, and a power cord 44, a wire 46, and an elastic body 48 as cables. In this embodiment, the elastic body 48 is, for example, a coil spring.

[0040] The electromagnet 42 is provided at the tip of the recovery tool 40. An electromagnetic coil 43 is fixed to the outer periphery of the electromagnet 42. A female thread is formed inside the electromagnet 42, and a connecting fitting (swage fitting) 45 is connected to the female thread. A power cord 44 and a wire 46 are connected to the electromagnet 42. The magnetic force of the electromagnet 42 is adjusted by turning the power on and off.

[0041] One end of the power cord 44 is connected to the electromagnet 42, and the other end is connected to positive and negative terminals for connection to a power source. The power cord 44 is bound together with wires 46 and fixed with tape at intervals.

[0042] The wire 46 includes two types of wires, a wire 46A (a first wire) and a wire 46B (a second wire), which differ in thickness and length. The first wire 46A is inserted into the steam generator 100 from the outside together with the power cord 44. An elastic body 48, which is a coil spring, is provided at the distal end of the first wire 46A. Specifically, the proximal end of the first wire 46A is provided outside the steam generator 100, and the distal end is connected to the proximal end of the elastic body 48. In this embodiment, the distal end of the first wire 46A and the proximal end of the elastic body 48 are fixed to each other by crimping with a connecting fitting 47. The second wire 46B is provided so as to protrude from the distal end of the elastic body 48 (the opposite side to the first wire 46A). Specifically, the proximal end of the second wire 46B and the distal end of the elastic body 48 are fixed to each other by crimping. An electromagnet 42 is provided at the tip of the second wire 46B. For example, the connection between the electromagnet 42 and the second wire 46B is preferably covered with tape. Also, the first wire 46A is preferably thicker than the second wire 46B.

[0043] In this way, by connecting the first wire 46A, the elastic body 48, the second wire 46B, and the electromagnet 42 in that order, the recovery tool 40 can be properly inserted into the cable housing 12 and the nozzle 14 by deformation of the elastic body 48.

[0044] (Cleaning Tools) 8, the cleaning tool 50 has a water-discharging nozzle 52 as a working part and a piping 59 as a cable. The piping 59 is a piping through which the cleaning liquid flows, and the water-discharging nozzle 52 is a nozzle in which a hole is formed through which the cleaning liquid is discharged.

[0045] The water-discharging nozzle 52 includes a nozzle portion 54, a screw member 56, and a connecting fitting 58. The water-discharging nozzle 52 is preferably made of metal, for example, and the length of the water-discharging nozzle 52 is preferably as short as possible.

[0046] The nozzle portion 54 has a spherical tip. The nozzle portion 54 has a plurality of holes 54A formed along the circumferential direction for discharging the cleaning liquid. These holes 54A preferably have the same shape and are preferably formed at equal intervals along the circumferential direction. The nozzle portion 54 is connected to the pipe 59 via a screw member 56 and a connecting fitting 58. The nozzle portion 54 has a male thread formed thereon that threadably engages with the screw member 56. Forming the male thread on the nozzle portion 54 in this manner allows the nozzle portion 54 to be replaced. In this embodiment, eight holes 54A are formed at equal intervals along the circumferential direction. The holes 54A are preferably formed so that the total area of the holes 54A is equal to the cross-sectional area of the interior space of the pipe 59. Two to four of the holes 54A are preferably formed to face downward. Therefore, the cleaning liquid discharged from the holes 54A can be applied to the tube support plate 108 without adjusting the direction of the cleaning tool 50. Here, the circumferential direction refers to the direction around the axial direction of the cleaning tool 50. The shape of the nozzle portion 54 and the number of holes 54A are not limited to a spherical shape or eight holes, and the shape, number of holes, hole diameter, position, etc. can be changed as appropriate.

[0047] One end of the screw member 56 is formed with a female thread into which the nozzle portion 54 is screwed, and the other end passes through a connecting fitting 58 and is inserted into a pipe 59. The connecting fitting 58 is a crimping fitting. The other end of the screw member 56 passes through the connecting fitting 58 to fix the screw member 56 in place.

[0048] The piping 59 is preferably a so-called high-pressure hose that can withstand high-pressure water discharge, and is preferably made by covering a flexible resin material (for example, nylon, Teflon (registered trademark), urethane, etc.) with a stainless steel wire mesh. One end of the piping 59 is formed into a threaded portion (not shown) that connects to the outside of the handhole H, and the other end is connected to the water-discharging nozzle 52. This reduces frictional resistance and allows the piping to be inserted smoothly between the heat-transfer tubes 104A without buckling.

[0049] <Work method> Next, a working method using the working equipment described above will be explained. Figure 9 is a flowchart showing the steps of the working method. Figures 10 to 12 are schematic diagrams for explaining the working method.

[0050] In the working method according to this embodiment, a step of inserting the cable housing 12, which has a nozzle at its tip, into the steam generator 100 through the hand hole H is performed (step S10). Specifically, by rotating the handle 13A of the feeding device 13, the cable housing 12 wound around the reel 13B is fed into the steam generator 100 through the guide tray 11. In this step, the cable housing 12 may be inserted into the steam generator 100 with the fixing tool 16, the work tool 30, and the camera tool 60 inserted therein, or the fixing tool 16, the work tool 30, and the camera tool 60 may be inserted into the cable housing 12 and the nozzle 14 after the cable housing 12 is inserted into the steam generator 100.

[0051] Next, a step is performed in which the fixing portion of the fixing tool 16 is exposed from the nozzle 14 and the nozzle 14 is fixed to the steam generator 100 using this fixing portion (step S12). Specifically, gas is supplied into the balloon 18 via the gas supply pipe 22 to inflate the balloon 18, thereby fixing the balloon 18 to the components of the steam generator 100. More specifically, as shown in FIG. 10 , in step S12, the balloon 18 is inserted into the flow slot 108A of the tube support plate 108 to be worked on and inflated. The balloon 18 is inserted into the flow slot 108A from above so that the nozzle 14 is positioned above the tube support plate 108. When the balloon 18 is inserted into the flow slot 108A, gas is supplied from the gas supply pipe 22 to the balloon 18, causing it to inflate. In this manner, the position of the nozzle 14 can be determined.

[0052] Next, as shown in Fig. 11, a step is performed in which the camera 65 of the camera tool 60 is advanced from the second opening 14B of the nozzle 14 to the outside of the nozzle 14 (step S14). As a result, an image captured by the camera 65 is displayed on the display means 64, making it possible to visually confirm the position facing the tip 14T2 of the nozzle 14. Thereafter, as shown in Fig. 12, a step is performed in which the working part of the work tool 30 is advanced from the first opening 14A of the nozzle 14 to the outside of the nozzle 14 (step S16). Then, with the working part of the work tool 30 exposed from the first opening 14A of the nozzle 14, work is performed by the working part.

[0053] More specifically, in this embodiment, work is performed using a recovery tool 40 as the work tool 30, and work is performed using a cleaning tool 50 as the work tool 30. Each work will be described below.

[0054] (Collection method) As shown in FIG. 12, in step S16, scale (foreign matter) S is collected by the collection tool 40. The collection tool 40 is exposed from the first opening 14A. The collection tool 40 is sent into the heat transfer tube 104A simultaneously (in parallel) with the camera tool 60. The collection tool 40 collects the scale S on the tube support plate 108 by magnetic force from the electromagnet 42. The collection tool 40 collects the scale S in order to inspect it. Therefore, when cleaning is also performed, it is preferable that the work tool 30 inserted first into the nozzle 14 is the collection tool 40. Collection by the collection tool 40 is preferably performed sequentially from the upper tube support plate 108 of the body 102 to the lower tube support plate 108.

[0055] (Cleaning method) As shown in FIGS. 7 and 12 , in step S16, the cleaning tool 50 discharges a cleaning liquid for cleaning. In this embodiment, the cleaning liquid is high-pressure water (for example, approximately 2 MPa to 4 MPa). Once the cleaning tool 50 and the camera tool 60 are inserted between the heat transfer tubes 104A, the discharge of high-pressure water begins. Then, while discharging water, the camera tool 60 is also sent to the heat transfer tubes 104A so that the cleaning tool 50 takes the lead. In this manner, scale S that has fallen onto the tube support plate 108 can be removed by the cleaning tool 50 while being monitored by the camera tool 60. Specifically, in cleaning, the scale S on the tube support plate 108 to be cleaned is dropped through a hole in the tube support plate 108 onto the tube support plate 108 located one level below. This process is repeated for each level until the tube support plate 108 located at the lowest position is reached. The scale S that has fallen onto the tube plate 106 is then collected together using an existing collection method other than the collection method of the present disclosure. Note that the cleaning liquid is not limited to high-pressure water and may be any suitable liquid.

[0056] The cleaning tool 50 may be exposed from the second opening 14B. In this case, the camera tool 60 is exposed from the first opening 14A. After the recovery operation, the work tool 30 may be replaced and the cleaning operation may be performed.

[0057] <Effects> The work tool 10 according to a first aspect of the present disclosure is for a steam generator 100 having a heat transfer tube 104A inside a trunk 102, and includes: a hollow cable housing 12 extending in the axial direction and insertable into a hand hole H formed in the trunk 102; a hollow nozzle 14 provided at the tip of the cable housing 12 and having a first opening 14A and a second opening 14B formed at the tip; a work tool 30 having a cable to be inserted into the cable housing 12 and the nozzle 14, and a working part provided at the tip of the cable and exposed from the first opening 14A; and a camera tool 60 having a cable to be inserted into the cable housing 12 and the nozzle 14, and a camera 65 provided at the tip of the cable and exposed from the second opening 14B. According to the present disclosure, work can be performed with the work tool 30 while monitoring with the camera 65 of the camera tool 60, so that appropriate work can be performed on foreign matter inside the steam generator 100.

[0058] A work implement 10 according to a second aspect of the present disclosure is the work implement 10 according to the first aspect, wherein a first space 14A1 having a first opening 14A formed at the tip, and a second space 14B1 having a second opening 14B formed at the tip and separated from the first space 14A1, are formed within the nozzle 14, and the work tool 30 is inserted into the first space 14A1, and the camera tool 60 is inserted into the second space 14B1. According to the present disclosure, the work tool 30 and the camera tool 60 can be inserted into the nozzle 14.

[0059] The work implement 10 according to a third aspect of the present disclosure is the work implement 10 according to the first or second aspect, wherein the nozzle 14 is curved from the base end 14T1 to the tip end 14T2. According to the present disclosure, the camera tool 60 and the work tool 30 can be sent to a targeted location.

[0060] The work implement 10 according to a fourth aspect of the present disclosure is the work implement 10 according to any of the first to third aspects, wherein a third opening 14C is formed in the nozzle 14, and the work implement 10 further includes a fixing tool 16 having a cable to be inserted into the cable housing 12 and the nozzle 14, and a fixing part provided at the tip of the cable, exposed from the third opening 14C, and fixed to the steam generator 100. According to the present disclosure, the position of the nozzle 14 can be fixed.

[0061] A work implement 10 according to a fifth aspect of the present disclosure is the work implement 10 according to the fourth aspect, wherein the fixed part is a balloon 18, and the cable of the fixed cable is a gas supply pipe 22 that supplies gas to the balloon 18. According to the present disclosure, the expansion of the balloon 18 can be adjusted by the amount of gas supplied, and the position of the nozzle 14 can be determined.

[0062] A work implement 10 according to a sixth aspect of the present disclosure is the work implement 10 according to any one of the first to fifth aspects, wherein the working section includes an electromagnet. According to the present disclosure, scale S can be collected.

[0063] A work implement 10 according to a seventh aspect of the present disclosure is the work implement 10 according to the sixth aspect, wherein the cable of the work tool 30 has a first wire 46A, an elastic body 48 provided at the tip of the first wire 46A, and a second wire 46B protruding from the elastic body 48 on the side opposite to the first wire 46A and having an electromagnet 42 provided at its tip. According to the present disclosure, the work tool 30 can be appropriately inserted into the nozzle 14.

[0064] The work implement 10 according to an eighth aspect of the present disclosure is the work implement 10 according to any of the first to seventh aspects, wherein the cable of the work tool 30 is a pipe 59 through which a cleaning liquid flows, and the working part is a water-discharging nozzle 52 formed with a hole 54A through which the cleaning liquid is discharged. According to the present disclosure, cleaning can be performed with a cleaning liquid.

[0065] The work implement 10 according to a ninth aspect of the present disclosure is the work implement 10 according to the eighth aspect, wherein the water-discharging nozzle 52 has a spherical tip and multiple holes 54A formed along the circumferential direction. According to the present disclosure, cleaning liquid can be efficiently discharged.

[0066] A work method according to a tenth aspect of the present disclosure is a work method using the work tool 10 according to any of the first to ninth aspects, and includes the steps of inserting the cable housing 12 into the steam generator 100 through the hand hole H, advancing the camera 65 of the camera tool 60 to the outside of the nozzle 14 from the second opening 14B of the nozzle 14, and advancing the working part of the work tool 30 to the outside of the nozzle 14 from the first opening 14A of the nozzle 14. According to the present disclosure, work can be performed using the work tool 30 while monitoring with the camera 65 of the camera tool 60.

[0067] Although the embodiments of the present disclosure have been described above, the embodiments are not limited to the contents of these embodiments. Furthermore, the above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the above-described components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the above-described embodiments. [Explanation of symbols]

[0068] 10 Work equipment 12 Cable holder 14 nozzles 14A First opening 14A1 1st space 14T1 Proximal end 14T2 Tip 14B 2nd opening 14B1 2nd space 14C 3rd opening 16 Fixing Tools 18 Balloon 22 Gas supply pipe 30 Work Tools 42 Electromagnet 46A First Wire 46B Second Wire 48 Elastic Body 52 Water nozzle 54A hole 59 Piping 60 Camera Tools 65 Camera 100 Steam Generator 102 Torso 104A heat transfer tube H Hand Hole S Scale (foreign matter)

Claims

1. A working device for a steam generator having a heat transfer tube inside a body portion, a hollow cable housing that can be inserted into a hand hole formed in the trunk portion and extends in the axial direction; a hollow nozzle provided at a tip of the cable housing, the nozzle having a first opening and a second opening formed at a tip portion; a cable inserted into the cable housing and the nozzle, and a work tool having a working portion provided at a tip of the cable and exposed from the first opening; a camera tool including a cable inserted into the cable housing and the nozzle, and a camera provided at a tip of the cable and exposed from the second opening; having work equipment.

2. a first space in which the first opening is formed at a tip end thereof, and a second space isolated from the first space in which the second opening is formed at a tip end thereof, The work implement of claim 1 , wherein the work tool is inserted into the first space and the camera tool is inserted into the second space.

3. The work tool according to claim 1 or 2, wherein the nozzle is curved from the base end toward the tip end.

4. The nozzle has a third opening formed therein, 3. The work equipment according to claim 1 or 2, further comprising: a fixing tool having a cable that is inserted into the cable housing and the nozzle, and a fixing portion that is provided at a tip of the cable, exposed from the third opening, and fixed to the steam generator.

5. The work equipment according to claim 4 , wherein the fixing part is a balloon, and the cable of the fixing tool is a gas supply tube that supplies gas to the balloon.

6. The work equipment according to claim 1 or 2, wherein the working part includes an electromagnet.

7. The cable of the work tool A first wire; an elastic body provided at a tip of the first wire; The work tool according to claim 6 , further comprising: a second wire that projects from the elastic body opposite to the first wire and has the electromagnet attached to a tip thereof.

8. 3. The work equipment according to claim 1, wherein the cable of the work tool is a pipe through which a cleaning liquid flows, and the working part is a water-discharging nozzle having a hole formed therein for discharging the cleaning liquid.

9. The work equipment according to claim 8 , wherein the water-discharging nozzle has a spherical tip and a plurality of the holes are formed along a circumferential direction.

10. A work method using the work equipment according to claim 1, inserting the cable housing into the steam generator through the hand hole; advancing a camera of the camera tool out of the nozzle through the second opening of the nozzle; advancing a working portion of the working tool out of the nozzle through the first opening of the nozzle; Including, How to work.

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