Inspection device and method for heat transfer pipe

Abstract

To provide an inspection device and a method for a heat transfer pipe that can inspect the heat transfer pipe in a wide range.SOLUTION: An inspection device for a steam generator is inserted inside from a hand hole of the steam generator to inspect a heat transfer pipe supported by a pipe supporting plate, and comprises: a supporting frame; an inspection arm which has one end part rotatably connected to one end part in a longitudinal direction in the supporting frame; a supporting arm which has one end part movably supported in the longitudinal direction of the supporting frame, and the other end part rotatably connected to the inspection arm; and an inspection probe supported by the other end part of the inspection arm.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a heat transfer tube inspection apparatus and method for inspecting heat transfer tubes from below a tube support plate in a steam generator. [Background technology]

[0002] A nuclear power plant is composed of a nuclear reactor, a steam generator, a steam turbine, a generator, etc. In the steam generator, multiple tube support plates and tube plates are arranged at intervals vertically inside the body, and multiple heat transfer tubes forming an inverted U shape are arranged inside the tube bundle outer cylinder. The ends of the heat transfer tubes penetrate the tube plates and communicate with the inlet side water chamber mirror and outlet side water chamber mirror of the primary cooling water provided at the lower end of the body. In addition, the multiple heat transfer tubes are supported by multiple tube support plates whose longitudinal middle parts are fixed to the tube bundle outer cylinder.

[0003] Steam generators need to be periodically inspected for the quality of the inside of the heat transfer tubes, etc. An example of an inspection device for a steam generator is described in the following Patent Document 1. The inspection device described in Patent Document 1 inspects the inside of the steam generator by inserting an inspection probe through a hand hole provided in the body of the steam generator. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2021-173468 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a steam generator, since a plurality of heat transfer tubes are arranged between a plurality of tube support plates, the gap between the heat transfer tubes is narrow, and the movement of the inspection probe between the top and bottom of the tube support plates is restricted. Therefore, the movement range of the inspection probe is limited, and it is desired to inspect the heat transfer tubes over a wide range inside the steam generator.

[0006] The present disclosure is devised to solve the above-mentioned problems, and aims to provide a heat transfer tube inspection device and method that enable inspection of heat transfer tubes over a wide range. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the heat transfer tube inspection device disclosed herein is a steam generator inspection device that is inserted into the interior of a steam generator through a hand hole and inspects heat transfer tubes supported on a tube support plate, and includes a support frame, an inspection arm having one end rotatably connected to one longitudinal end of the support frame, a support arm having one end supported so as to be freely movable in the longitudinal direction of the support frame and the other end rotatably connected to the inspection arm, and an inspection probe supported on the other end of the inspection arm.

[0008] In addition, the heat transfer tube inspection method disclosed herein includes the steps of inserting the heat transfer tube inspection device into an upper surface of the tube support plate through a hand hole of the steam generator, erecting the heat transfer tube inspection device, raising the support frame to pass through a flow slot of the tube support plate and stopping it at a predetermined inspection position, moving the support arm to rotate the inspection arm, and inspecting the heat transfer tube with the inspection probe. Effect of the Invention

[0009] According to the heat transfer tube inspection device and method disclosed herein, heat transfer tube inspection can be performed over a wide range. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the internal configuration of a steam generator. [Diagram 2] FIG. 2 is a schematic diagram showing a tube support plate. [Diagram 3] FIG. 3 is a front view showing the heat transfer tube inspection device of the present embodiment. [Figure 4]FIG. 4 is a side view showing an inspection device for a heat transfer tube. [Diagram 5] FIG. 5 is a plan view showing a clamp device provided on the base member. [Figure 6] FIG. 6 is a side view showing a clamp device provided on the base member. [Figure 7] FIG. 7 is a plan view showing a guide device provided on the first frame. [Figure 8] FIG. 8 is a flowchart showing the heat transfer tube inspection method of the present embodiment. [Figure 9] FIG. 9 is a schematic diagram illustrating the heat transfer tube inspection method of the present embodiment. [Figure 10] FIG. 10 is a schematic diagram showing a modified example of the inspection arm assembly. [Figure 11] FIG. 11 is a schematic diagram showing a modified example of the inspection arm assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that the present disclosure is not limited to these embodiments, and when there are multiple embodiments, the present disclosure also includes a configuration in which each embodiment is combined. In addition, the components in the embodiments include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the so-called equivalent range.

[0012] <Steam generator> FIG. 1 is a schematic diagram showing the internal configuration of a steam generator.

[0013] As shown in Fig. 1, the steam generator 100 is a heat exchanger used in a nuclear power plant. The steam generator 100 exchanges heat between primary cooling water heated to a high temperature in a nuclear reactor and secondary cooling water supplied to a steam turbine. The steam generator 100 exchanges heat between the primary cooling water and the secondary cooling water, thereby heating the secondary cooling water with the primary cooling water and generating steam.

[0014] The steam generator 100 is disposed along the vertical direction. The steam generator 100 has a body 102. The body 102 has a hollow cylindrical shape. A heat transfer tube group 104 is provided inside the body 102. The heat transfer tube group 104 is composed of a plurality of heat transfer tubes 105 forming an inverted U shape. The heat transfer tubes 105 are disposed so that the arc portion forming the inverted U shape at the upper portion is convex upward. The heat transfer tubes 105 are supported at their lower ends by a tube plate 106, and their middle portions are supported by the body 102 via a plurality of tube support plates 108. The tube support plate 108 has a large number of through holes formed therein, and the heat transfer tubes 105 are inserted through the through holes. The tube support plates 108 are disposed at predetermined intervals (preferably at equal intervals) along the vertical direction.

[0015] The body 102 is provided with a water chamber 110 at its lower end. The water chamber 110 is bowl-shaped, and the inside 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 105 is connected to the inlet side water chamber 114, and the other end of the heat transfer tube 105 is connected to the outlet side water chamber 116. The inlet side water chamber 114 is formed with an inlet side nozzle 115 that communicates with the outside of the body 102, and the outlet side water chamber 116 is formed with an outlet side nozzle 117 that communicates with the outside of the body 102. The inlet side nozzle 115 is connected to a primary cooling water pipe (not shown) from the pressurized water reactor, and the outlet side nozzle 117 is connected to a primary cooling water pipe (not shown) that sends the primary cooling water after heat exchange to the pressurized water reactor.

[0016] The upper half of the body 102 is provided with a steam-water separator 118 for separating feed water into steam and hot water, and a moisture separator 120 for removing moisture from the separated steam to produce a state close to dry steam. Between the steam-water separator 118 and the heat transfer tube group 104, a water supply pipe 122 for supplying secondary cooling water from the outside into the body 102 is inserted into the body 102. A steam outlet 124 is formed at the upper end of the body 102. A water supply passage 128 is formed in the lower half of the body 102, which causes the secondary cooling water supplied from the water supply pipe 122 to flow down between the body 102 and the tube group outer casing 126, turn around at the tube plate 106, and rise along the heat transfer tube group 104. In addition, the steam outlet 124 is connected to a secondary cooling water pipe (not shown) that sends steam to the steam turbine, and the water supply pipe 122 is connected to a secondary cooling water pipe (not shown) for supplying secondary cooling water that has been cooled by a condenser (not shown) from the steam used in the steam turbine.

[0017] The body 102 is provided with hand holes 132, 134 that communicate between the inside and the outside. The hand holes 132, 134 are provided, for example, on the side surfaces of the upper and lower halves of the body 102. In this embodiment, the hand holes 132, 134 are provided above the lowest tube support plate 108 and above the highest tube support plate 108. The hand holes 132, 134 are also provided penetrating the tube bundle outer cylinder 126, and configured to enable access to the tube support plate 108 from the outside of the body 102. Note that the hand holes 132, 134 are closed by attaching a lid when the steam generator 100 is used. The hand holes 132, 134 are provided on both sides of the body 102 so as to pass through the center of the inverted U-shape of the heat transfer tube 105 and face each other.

[0018] <Pipe support plate> FIG. 2 is a schematic diagram showing a tube support plate.

[0019] As shown in Fig. 2, a tube support plate 108 is disposed inside the body 102. The tube support plate 108 has a large number of through holes 109 formed therein, and the heat transfer tubes 105 are inserted into the through holes 109. That is, the heat transfer tubes 105 are supported by being inserted into the through holes 109 of the tube support plate 108. The tube support plate 108 has a flow slot 136 formed in a central portion thereof and having an oval shape in the radial direction. The flow slots 136 are disposed in series at intervals in the radial direction of the tube support plate 108. The heat transfer tubes 105 are disposed on both sides of the flow slots 136.

[0020] Note that multiple tube support plates 108 are arranged at intervals in the vertical direction inside the body 102, and the multiple tube support plates 108 have the same shape. That is, the multiple tube support plates 108 have multiple flow slots 136 located at the same radial positions on the tube support plates 108. The fluid (secondary cooling water) flowing inside the body 102 passes through the flow slots 136.

[0021] <Heat transfer tube inspection equipment> FIG. 3 is a front view showing the heat transfer tube inspection device of the first embodiment, and FIG. 4 is a plan view showing the heat transfer tube inspection device.

[0022] As shown in Figures 3 and 4, the heat transfer tube inspection device (hereinafter simply referred to as the inspection device) 10 is inserted into the space between multiple tube support plates 108 from a hand hole 132 of the steam generator 100 to inspect the tube support plates 108 and the heat transfer tubes 105 supported by the tube support plates 108.

[0023] The inspection device 10 includes a base member 11, a moving mechanism assembly 12, an inspection arm assembly 13, and an inspection probe 14. The base member 11, the moving mechanism assembly 12, and the inspection arm assembly 13 are each configured independently and can be assembled and disassembled. Specifically, the base member 11, the moving mechanism assembly 12, and the inspection arm assembly 13 can be inserted into the inside of a steam generator 100 (see FIG. 1) individually, and can be removed from the steam generator 100 individually. The moving mechanism assembly 12 and the inspection arm assembly 13 are assembled inside the steam generator 100 and can operate in cooperation with each other. The base member 11 and the moving mechanism assembly 12 (inspection arm assembly 13) are detachably assembled inside the steam generator 100 and can operate in cooperation with each other, and the moving mechanism assembly 12 (inspection arm assembly 13) can be detached from the base member 11 and can operate.

[0024] The base member 11 has a standing base 21, a standing guide 22, and a standing bracket 23. The standing base 21, the standing guide 22, and the standing bracket 23 are disassembled, can be inserted into the steam generator 100 through a hand hole 132, and have an external shape (length, width, height) that fits into the flow slot 136 and prevents them from falling off from the flow slot 136.

[0025] The standing base 21 has a predetermined length and can be placed on the tube support plate 108. A first support recess 21a and a second support recess 21b are formed on the upper surface of the standing base 21. The standing guide 22 has a length shorter than the standing base 21 and is placed on the standing base 21. That is, the standing guide 22 is positioned by being placed in the first support recess 21a of the standing base 21.

[0026] The standing bracket 23 is placed on one side of the standing guide 22 on the standing base 21. That is, the standing bracket 23 is positioned by being placed in the second support recess 21b of the standing base 21. The standing bracket 23 has a pair of support walls 23a, and a stopper pin 23b is fixed to the inside of the pair of support walls 23a. In addition, a hinge pin 23c penetrating the pair of support walls 23a is fixed to the standing bracket 23.

[0027] The movement mechanism assembly 12 includes a first frame 31 , a first connecting frame 32 , and a movement mechanism 33 .

[0028] The first frame 31 has one end (lower end in FIG. 3) in the longitudinal direction supported by the base member 11 so as to be rotatable and detachable. The first frame 31 has a bifurcated portion 31a at its lower end, and a stopper 31b is fixed to it. The bifurcated portion 31a of the first frame 31 engages with the hinge pin 23c of the standing base 21. Therefore, the first frame 31 is supported so as to be rotatable about the hinge pin 23c of the standing base 21 with which the bifurcated portion 31a engages, and is supported so as to be detachable. When the first frame 31 stands up relative to the standing base 21 with the hinge pin 23c as a fulcrum, the stopper 31b comes into contact with the stopper pin 23b, thereby maintaining the first frame 31 in an upright state.

[0029] The first connecting frame 32 is disposed adjacent to the first frame 31 in parallel. The moving mechanism 33 is installed between the first frame 31 and the first connecting frame 32. The moving mechanism 33 is a pantograph mechanism and has two rotating links 33a. However, the moving mechanism 33 is not limited to the pantograph mechanism and may be, for example, a ball screw mechanism. The two rotating links 33a are configured such that their middle parts are rotatably connected by a rotating shaft 33b so as to intersect. In the moving mechanism 33, one end of each of the pair of rotating links 33a is rotatably connected to the first frame 31 by a connecting shaft 33c, and the other end is rotatably connected to the first connecting frame 32 by a connecting shaft 33d.

[0030] The inspection arm assembly 13 includes a second connecting frame 41, a guide member 42, an inspection arm 43, and a support arm 44.

[0031] The second connecting frame 41 is disposed adjacent to and parallel to the first connecting frame 32. The second connecting frame 41 and the first connecting frame 32 are detachably fastened to each other, for example, by a plurality of bolts. The guide member 42 is fixed integrally to the second connecting frame 41 on the opposite side to the first connecting frame 32. The guide member 42 is provided with a guide groove 42a along the longitudinal direction.

[0032] The inspection arm 43 has one longitudinal end rotatably connected to one end of the second connecting frame 41 by a connecting shaft 45. The support arm 44 has one longitudinal end rotatably connected to the other longitudinal end of the inspection arm 43 by a connecting shaft 46. A slide member 47 is fixed to the other longitudinal end of the support arm 44, and the slide member 47 is supported movably in the guide groove 42a of the guide member 42. One end side of the support arm 44 is bent toward the inspection arm 43 and connected to the inspection arm 43.

[0033] Therefore, when the slide member 47 of the support arm 44 is located at one end side of the guide groove 42a (the lower end side in Figs. 1 and 2), the inspection arm 43 and the support arm 44 are located at a position substantially parallel to the second connecting frame 41. When the slide member 47 of the support arm 44 moves from this state to the other end side of the guide groove 42a (the upper end side in Figs. 1 and 2), the support arm 44 rotates counterclockwise in Fig. 4 with the slide member 47 as a fulcrum. Then, the inspection arm 43 rotates clockwise by approximately 90 degrees in Fig. 4 with the connecting shaft 45 as a fulcrum.

[0034] Here, a second frame is formed by the first connecting frame 32 and the second connecting frame 41. The first frame 31 and the second frame (the first connecting frame 32 and the second connecting frame 41) form a support frame.

[0035] The inspection probe 14 performs a visual inspection of the heat transfer tube 105 inside the steam generator 100. The inspection probe 14 is supported at the other end of the inspection arm 43. A probe guide 48 is provided at the other end of the inspection arm 43. The probe guide 48 guides a guide tube 49. The inspection probe 14 is movable to the other end of the inspection arm 43 through the guide tube 49. The inspection probe 14 is connected to an inspection device (not shown) via an inspection cable.

[0036] <Clamping device> FIG. 5 is a plan view showing a clamp device provided on the base member, and FIG. 6 is a side view showing the clamp device provided on the base member.

[0037] As shown in FIG. 5 and FIG. 6, the base member 11 has a clamp device 51 that positions it on the upper surface of the tube support plate 108. That is, when the base member 11 is placed on the upper surface of the tube support plate 108, the horizontal movement of the base member 11 is suppressed by its own weight, but the clamp device 51 is provided to appropriately position the horizontal movement of the base member 11. In addition, the clamp device 51 prevents the horizontal movement of the erection base 21 when the erection guide 22 is erected relative to the erection base 21. Furthermore, the clamp device 51 positions the base member 11, thereby enabling recovery from the hand hole 132. The clamp device 51 is disposed on the other side of the erection guide 22 on the erection base 21. The erection base 21 has a cylinder mechanism 52 fixed to its upper surface, and the cylinder mechanism 52 supports two clamp plates 53 so as to be freely movable. Each of the two clamp plates 53 has an arc-shaped recess at its tip. The recesses at the tips of the clamp plates 53 correspond to the arc shape of the outer circumferential surface of the heat transfer tube 105. The movement direction of the two clamp plates 53 is a direction intersecting the longitudinal direction of the flow slot 136.

[0038] The cylinder mechanism 52 can move the two clamp plates 53 to an unclamped position where they approach each other, and to a clamped position where they are separated from each other. When the two clamp plates 53 are located at the unclamped position, the two clamp plates 53 move away from the heat transfer tubes 105, allowing the base member 11 to move freely on the tube support plate 108. When the two clamp plates 53 are located at the clamped position, the two clamp plates 53 press and contact the heat transfer tubes 105, causing the base member 11 to be clamped to the heat transfer tubes 105 and unable to move on the tube support plate 108.

[0039] <Guide device> FIG. 7 is a plan view showing a guide device provided on the first frame.

[0040] The first frame 31 in the movement mechanism assembly 12 has a guide device 61 that can be supported movably in the longitudinal direction relative to the heat transfer tube 105. A plurality of guide devices 61 (e.g., three) are arranged at intervals in the longitudinal direction of the first frame 31. A cylinder mechanism 62 is fixed inside the first frame 31, and the cylinder mechanism 62 movably supports two brackets 63. A guide roller 64 is rotatably supported at the tip of each of the two brackets 63. The guide roller 64 of the bracket 63 corresponds to the arc shape of the outer circumferential surface of the heat transfer tube 105. The movement direction of the two brackets 63 and the guide roller 64 is a direction that intersects the longitudinal direction of the flow slot 136.

[0041] The cylinder mechanism 62 can move the two guide rollers 64 (brackets 63) to a guide release position where they approach each other and a guide position where they are separated from each other. When the two guide rollers 64 are located at the guide release position, the two guide rollers 64 move away from the heat transfer tube 105, and the first frame 31 is free to move in the horizontal and vertical directions relative to the heat transfer tube 105. When the two guide rollers 64 are located at the guide position, the two guide rollers 64 press and contact the heat transfer tube 105, and the first frame 31 is guided by the heat transfer tube 105, and is free to move in the vertical direction while its horizontal movement relative to the heat transfer tube 105 is restricted. In addition, the guide device 61 prevents the first frame 31 from falling.

[0042] <Modifications of the Inspection Arm Assembly> 10 and 11 are schematic diagrams showing a modified testing arm assembly.

[0043] The above-mentioned inspection arm assembly 13 has a second connecting frame 41, a guide member 42, an inspection arm 43, and a support arm 44, but the configuration of the inspection arm assembly 13, i.e., the length of the inspection arm 43, may be changed depending on the size and shape of the steam generator 100, or the inspection position, etc.

[0044] As shown in FIG. 10, the inspection arm assembly 13A has a second connecting frame 41, a guide member 42, an inspection arm 43A, and a support arm 44. The inspection arm 43A is relatively long, and the inspection probe 14 can be used to perform an inspection at a position away from the second connecting frame 41. As shown in FIG. 11, the inspection arm assembly 13B has a second connecting frame 41, a guide member 42, an inspection arm 43B, and a support arm 44. The inspection arm 43B is relatively short, and the inspection probe 14 can be used to perform an inspection at a position close to the second connecting frame 41. The inspection device 10 can inspect the heat transfer tube 105 over a wide range by preparing multiple types of inspection arm assemblies 13, 13A, and 13B in advance.

[0045] <Inspection method for heat transfer tubes> FIG. 8 is a flowchart showing the heat transfer tube inspection method of the present embodiment, and FIG. 9 is a schematic diagram showing the heat transfer tube inspection method of the present embodiment.

[0046] The heat transfer tube inspection method includes the steps of inserting the inspection device 10 onto the tube support plate 108 through the hand hole 132 of the steam generator 100, standing the inspection device 10, raising the support frame so that it passes through the flow slot 136 of the tube support plate 108 and stops it at a predetermined inspection position, moving the support arm 44 to rotate the inspection arm 43, and inspecting the heat transfer tube 105 with the inspection probe 14.

[0047] As shown in Figures 8 and 9, the method for inspecting a heat transfer tube involves first assembling the base member 11, the moving mechanism assembly 12, the inspection arm assembly 13, and the inspection probe 14 that constitute the inspection device 10 by individually inserting them into the steam generator 100.

[0048] The steam generator 100 has a winch (lifting device) 71 for lifting and lowering the inspection device 10 disposed on the outside of the upper part, and a drive device 72 for operating the movement mechanism 33 and the inspection arm 43 disposed therein. The winch 71 has a lifting wire 73 disposed inside the steam generator 100 through a hand hole 134B. The drive device 72 has two pulling wires 74, 75 disposed inside the steam generator 100 through a hand hole 134B. The pulling wire 74 is connected to the movement mechanism 33, and the pulling wire 75 is connected to the inspection arm 43. The pulling wires 74, 75 are configured such that a control wire is movably supported inside the outer casing, and various devices are operated by moving the control wire.

[0049] An operator can operate the winch 71 to raise and lower the inspection device 10 (the moving mechanism assembly 12 and the inspection arm assembly 13) via the lifting wire 73. The operator operates the driving device 72 to pull the pulling wire 74 to operate the moving mechanism 33 in one direction and move the inspection arm assembly 13 away from the moving mechanism assembly 12. The operator also operates the driving device 72 to pull the pulling wire 75 to rotate the inspection arm 43 in one direction to a horizontal position. The driving device 72 may be a motor or a manual pulling tool.

[0050] In addition, a monitoring device 76 for monitoring the inside is disposed on the outside of the upper portion of the steam generator 100. In the monitoring device 76, a monitoring camera 77 is disposed inside the steam generator 100 from a hand hole 134A, and monitors the operation of the inspection device 10 through a flow slot 136.

[0051] The steam generator 100 has a driving device 81 disposed on the outside of the lower part for operating the moving mechanism 33 and the inspection arm 43. The driving device 81 has two pulling wires 82, 83 arranged inside the steam generator 100 through a hand hole 132A. The pulling wire 82 is connected to the moving mechanism 33, and the pulling wire 83 is connected to the inspection arm 43. The pulling wires 82, 83 are configured by a control wire supported movably inside the outer casing, and various devices are operated by moving the control wire. The operator operates the driving device 81 to pull the pulling wire 82 to operate the moving mechanism 33 in the other direction, and moves the inspection arm assembly 13 closer to the moving mechanism assembly 12. The operator also operates the driving device 81 to pull the pulling wire 83 to rotate the inspection arm 43 in the other direction to a vertical state. The driving device 81 may be a motor or the like, or may be a manual pulling tool.

[0052] In step S11, the worker inserts the standing base 21 constituting the base member 11 into the inside of the steam generator 100 from the hand hole 132A. At this time, the worker places the standing base 21 on the upper surface of the first tube support plate 108A at the lowest stage from the outside of the steam generator 100 through the hand hole 132A. The standing base 21 is placed on the upper surface of the first tube support plate 108A and on the flow slot 136 between the multiple heat transfer tubes 105. In step S12, the worker inserts the standing guide 22 constituting the base member 11 into the inside of the steam generator 100 from the hand hole 132A. At this time, the worker places the standing guide 22 on the standing base 21 placed on the first tube support plate 108A from the outside of the steam generator 100 through the hand hole 132A, and positions it at a predetermined position.

[0053] In step S13, the worker connects the movement mechanism assembly 12 to the lifting wire 73 from the winch 71 and the pulling wires 74, 75 from the driving device 72. Specifically, one end of the pulling wires 74, 75, one end of which is connected to the movement mechanism assembly 12 outside the steam generator 100, is inserted into the steam generator 100 through the hand hole 132A, and the other end is wound up by the winch 71.

[0054] In step S14, the worker inserts the movement mechanism assembly 12 into the inside of the steam generator 100 through the hand hole 132A. At this time, the worker places the movement mechanism assembly 12 from the hand hole 132A onto the upright guide 22 of the base member 11 placed on the first tube support plate 108A from the outside of the steam generator 100, and positions it at a predetermined position. In step S15, the worker inserts the inspection arm assembly 13 into the inside of the steam generator 100 through the hand hole 132A. At this time, the worker places the inspection arm assembly 13 from the hand hole 132A onto the movement mechanism assembly 12 placed on the first tube support plate 108A from the outside of the steam generator 100, and connects and assembles them.

[0055] In step S16, the worker inserts the standing bracket 23 constituting the base member 11 into the inside of the steam generator 100 through the hand hole 132A. At this time, the worker places the standing bracket 23 on the standing base 21 placed on the first tube support plate 108A from the outside of the steam generator 100 through the hand hole 132A, and positions it at a predetermined position. Then, the bifurcated portion 31a of the first frame 31 constituting the movement mechanism assembly 12 and the hinge pin 23c of the standing bracket 23 are engaged with each other.

[0056] In step S17, the worker moves the inspection device 10 using the stand-up jig 91 from the hand hole 132A and stops it at the target position. Here, the clamp device 51 of the base member 11 is operated to press the clamp plate 53 against the heat transfer tube 105, thereby restraining the base member 11 from moving on the tube support plate 108 relative to the heat transfer tube 105. In step S18, the moving mechanism assembly 12 and the inspection arm assembly 13, which are assembled together, are raised relative to the base member 11. At this time, the worker operates the winch 71 to lift up the end of the moving mechanism assembly 12 via the lifting wire 73, and pushes the end of the moving mechanism assembly 12 upwards using the stand-up jig 91 from the hand hole 132b. Then, the moving mechanism assembly 12 and the inspection arm assembly 13 rotate about the base member 11 as a fulcrum and are raised.

[0057] In step S19, the guide device 61 of the moving mechanism assembly 12 is operated to press the guide roller 64 against the heat transfer tube 105, thereby enabling the moving mechanism assembly 12 and the inspection arm assembly 13 to move in the vertical direction while being supported by the heat transfer tube 105. In step S20, the winch 71 is operated to lift and raise the moving mechanism assembly 12 via the lifting wire 73. At this time, the moving mechanism assembly 12 and the inspection arm assembly 13 can pass through the tube support plates 108B and 108C by passing through the flow slot 136. In addition, when the moving mechanism assembly 12 and the inspection arm assembly 13 pass through the flow slot 136, the guide device 61 is operated to release the pressure of the guide roller 64 on the heat transfer tube 105.

[0058] In step S21, the moving mechanism assembly 12 and the inspection arm assembly 13 are stopped at a predetermined inspection position (for example, the space between the tube support plate 108C and the tube support plate 108D). In step S22, the inspection probe 14 is inserted into the guide tube 49 and moved to the other end of the inspection arm 43 in the inspection arm assembly 13.

[0059] In step S23, the driving device 72 is operated to pull the pulling wire 74, and the moving mechanism 33 is operated to move the inspection arm assembly 13 away from the moving mechanism assembly 12, and the inspection arm assembly 13 is moved horizontally, i.e., in the longitudinal direction of the flow slot 136, and stopped at a predetermined position. In step S24, the driving device 72 is operated to pull the pulling wire 75, and the inspection arm 43 is operated via the support arm 44, and the inspection arm 43 is moved horizontally, i.e., in the direction intersecting the longitudinal direction of the flow slot 136, until it is in a horizontal state. In step S25, the inspection probe 14 inspects the undersides of the heat transfer tubes 105 and the tube support plate 108.

[0060] When the inspection of the undersides of the heat transfer tubes 105 and tube support plates 108 by the inspection probe 14 is completed, the moving mechanism assembly 12 and the inspection arm assembly 13 are moved to another location, and the inspection is performed in the same manner. When the inspection of the undersides of all of the heat transfer tubes 105 and tube support plates 108 is completed, the inspection device 10 is discharged to the outside of the steam generator 100 by performing the above-described operations in reverse.

[0061] [Effects of this embodiment] The heat transfer tube inspection device of the first embodiment comprises a support frame, an inspection arm 43 having one end rotatably connected to one longitudinal end of the support frame (second connecting frame 41), a support arm 44 having one end supported for movement in the longitudinal direction of the second connecting frame 41 and the other end rotatably connected to the inspection arm 43, and an inspection probe 14 supported on the other end of the inspection arm 43.

[0062] According to the heat transfer tube inspection device of the first embodiment, the inspection arm 43 can pass through the flow slot 136 of the tube support plate 108 while being in close contact with the support frame (second connecting frame 41), and the inspection arm 43 can rotate the support frame (second connecting frame 41) by the support arm 44 to bring the inspection probe 14 closer to a desired inspection position. As a result, inspection of a plurality of heat transfer tubes 105 can be performed over a wide range.

[0063] The heat transfer tube inspection device according to the second embodiment is the heat transfer tube inspection device according to the first embodiment, further comprising: a support frame having a first frame 31 and a second frame (a first connecting frame 32 and a second connecting frame 41); a moving mechanism 33 that is installed between the first frame 31 and the first connecting frame 32 and connects the first frame 31 and the first connecting frame 32 so that they can approach and separate from each other; and an inspection arm 43 that is connected to the first connecting frame 32. This allows the inspection arm 43, which is provided on the first connecting frame 32 side with respect to the first frame 31, to be moved in the horizontal direction by the moving mechanism 33, and the inspection probe 14 can be moved to an area horizontally away from the flow slot 136, thereby expanding the inspection range by the inspection probe 14.

[0064] The heat transfer tube inspection device according to the third aspect is the heat transfer tube inspection device according to the second aspect, further comprising: the second frame having a first connecting frame 32 and a second connecting frame 41; a moving mechanism 33 is connected to the first connecting frame 32; an inspection arm 43 is connected to the second connecting frame 41; and the first connecting frame 32 and the second connecting frame 41 are detachably connected. Thus, by making the moving mechanism assembly 12 and the inspection arm assembly 13 detachable, they can be individually inserted into the steam generator 100 from the outside.

[0065] The heat transfer tube inspection device according to the fourth aspect is the heat transfer tube inspection device according to the second or third aspect, and further, the first frame 31 has a guide device 61 that can support the heat transfer tube 105 so as to be movable in the longitudinal direction of the heat transfer tube 105. This allows the guide device 61 to stably move the movement mechanism assembly 12 and the inspection arm assembly 13 along the heat transfer tube 105.

[0066] The heat transfer tube inspection device according to the fifth aspect is the heat transfer tube inspection device according to any one of the second to fourth aspects, and further includes a base member 11 that is disposed on the upper surface of the tube support plate 108 and rotatably supports the other longitudinal end of the first frame 31. This allows the movement mechanism assembly 12 and the inspection arm assembly 13 to be rotated relative to the base member 11 to stand up.

[0067] The heat transfer tube inspection device according to the sixth embodiment is the heat transfer tube inspection device according to the fifth embodiment, and further, the base member 11 and the first frame 31 are detachably connected to each other. This allows the base member 11 and the movement mechanism assembly 12 to be individually inserted into the steam generator 100 and assembled, and allows the movement mechanism assembly 12 and the inspection arm assembly 13 to be raised relative to the base member 11.

[0068] The heat transfer tube inspection device according to the seventh aspect is the heat transfer tube inspection device according to the fifth or sixth aspect, and further includes a clamp device 51 that positions the base member 11 on the upper surface of the tube support plate 108. Thus, by positioning the base member 11 on the tube support plate 108 using the clamp device 51, the movement mechanism assembly 12 and the inspection arm assembly 13 can be appropriately raised and lowered relative to the base member 11.

[0069] The heat transfer tube inspection device according to the eighth aspect is the heat transfer tube inspection device according to any one of the first to seventh aspects, and further includes a winch (lifting device) 71 that lifts and lowers the support frame. As a result, the movement mechanism assembly 12 and the inspection arm assembly 13 are lifted and lowered inside the steam generator 100 by the winch 71, so that the inspection probe 14 can be moved to a desired inspection position.

[0070] The heat transfer tube inspection device according to the ninth aspect is the heat transfer tube inspection device according to any one of the first to eighth aspects, and further includes a drive device 81 that operates the inspection arm 43 from outside the steam generator 100 via the support arm 44. This allows the inspection arm 43 to be operated from outside the steam generator 100 by the drive device 81.

[0071] The heat transfer tube inspection device according to the tenth aspect is the heat transfer tube inspection device according to any one of the first to ninth aspects, and further includes a tip end of a guide tube 49 supported on the other end of the inspection arm 43, and the inspection probe 14 is supported movably inside the guide tube 49. This allows the inspection probe 14 to be easily moved to the inspection position.

[0072] The heat transfer tube inspection method according to the eleventh aspect includes the steps of inserting the inspection device 10 onto the tube support plate 108 through the hand hole 132 of the steam generator 100, erecting the inspection device 10, raising the support frame to pass through the flow slot 136 of the tube support plate 108 and stopping it at a predetermined inspection position, moving the support arm 44 to rotate the inspection arm 43, and inspecting the heat transfer tube 105 with the inspection probe 14. As a result, the inspection arm 43 rotates the support frame (second connection frame 41) with the support arm 44, so that the inspection probe 14 can approach the desired inspection position. As a result, inspection of a plurality of heat transfer tubes 105 can be performed over a wide range. [Explanation of symbols]

[0073] 10 Inspection equipment 11 Base material 12 Moving mechanism assembly 13 Inspection arm assembly 14 Inspection probe 21 Standing Base 22 Standing Guide 23 Standing bracket 31 First frame (support frame) 32 1st connecting frame (support frame, 2nd frame) 33 Moving mechanism 41 Second connecting frame (support frame, second frame) 42 Guide member 43 Test Arm 44 Support Arm 49 Guide Tube 51 Clamping device 52 Cylinder mechanism 53 Clamp plate 61 Guide device 62 Cylinder mechanism 63 Bracket 64 Guide roller 71 Winch (lifting device) 72 Drive unit 81 Drive unit 100 Steam Generator 132,134 Hand Hole 136 Flow Slot

Claims

1. A steam generator inspection device that is inserted into a steam generator through a hand hole and inspects a heat transfer tube supported by a tube support plate, comprising: A support frame; an inspection arm having one end rotatably connected to one end of the support frame in a longitudinal direction; a support arm having one end supported by the support frame so as to be movable in the longitudinal direction thereof and having the other end rotatably connected to the inspection arm; a test probe supported on the other end of the test arm; A heat transfer tube inspection device comprising:

2. the support frame has a first frame and a second frame, and a moving mechanism is installed between the first frame and the second frame to connect the first frame and the second frame so that the first frame and the second frame can approach and separate from each other, and the inspection arm is connected to the second frame. The heat transfer tube inspection device according to claim 1.

3. the second frame has a first connecting frame and a second connecting frame, the moving mechanism is connected to the first connecting frame, the inspection arm is connected to the second connecting frame, and the first connecting frame and the second connecting frame are detachably connected to each other. The heat transfer tube inspection device according to claim 2.

4. the first frame has a guide device capable of supporting the heat transfer tube so as to be movable in a longitudinal direction of the heat transfer tube; The heat transfer tube inspection device according to claim 2.

5. a base member disposed on an upper surface of the tube support plate and rotatably supporting the other end of the first frame in the longitudinal direction; The heat transfer tube inspection device according to claim 2.

6. The base member and the first frame are detachably connected to each other. The heat transfer tube inspection device according to claim 5.

7. The base member has a clamp device that is positioned on the upper surface of the tube support plate. The heat transfer tube inspection device according to claim 5.

8. A lifting mechanism for lifting and lowering the support frame is provided. The heat transfer tube inspection device according to claim 1.

9. a drive device that operates the inspection arm via the support arm from outside the steam generator; The heat transfer tube inspection device according to claim 1.

10. a tip end of a guide tube is supported at the other end of the inspection arm, and the inspection probe is supported movably inside the guide tube; The heat transfer tube inspection device according to claim 1.

11. inserting the heat transfer tube inspection device according to claim 1 into an upper surface of the tube support plate through a hand hole of the steam generator; standing up the heat transfer tube inspection device; lifting the support frame through the flow slots of the tube support plate and stopping at a predetermined inspection position; moving the support arm to rotate the testing arm; performing an inspection of the heat transfer tube with the inspection probe; A method for inspecting a heat transfer tube having the above structure.

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