Guide pipe adjusting device and method for eddy current inspection of steam generator

Abstract

The invention discloses a guide pipe adjusting device and method for steam generator eddy current inspection, the device comprises a mounting shell, a first cam, a first guide wheel and a driving assembly, the first cam and the first guide wheel are arranged in the mounting shell and are oppositely arranged, the driving assembly is used for driving the first cam to rotate, and an advancing and retreating gap is formed between the first cam and the first guide wheel; an advancing and retreating hole is formed in the position, opposite to the advancing and retreating gap, of the mounting shell, and the shortest distance between the first cam and the first guide wheel is smaller than the diameter of the guide pipe in the free state. The cam is driven by the driving mechanism to press the catheter, meanwhile, the catheter is driven to move through friction force between the cam and the catheter, remote control over the catheter can be achieved, and irradiation of personnel dosage is avoided.

Description

Technical Field

[0001] The present invention belongs to the field of nuclear power detection equipment, and particularly relates to a catheter adjusting device and method for eddy current inspection of steam generators. Background Art

[0002] The catheter length adjusting device for eddy current inspection of the steam generator of the present invention mainly relates to the adjustment of the catheter length between the probe pusher and the steam generator tube sheet locator in the eddy current inspection project of the steam generator. A steam generator is a heat exchange device that transfers the heat obtained by the primary coolant from the reactor to the secondary medium to turn it into steam. The steam generator consists of a lower head, a tube sheet, a U-shaped tube bundle, a steam-water separation device and a cylinder assembly. On the primary side, the coolant from the reactor enters the inlet water chamber through the inlet nozzle of the lower head, and then transfers the heat to the secondary working medium through the U-shaped tubes. After the coolant flows out of the U-shaped tube bundle, it enters the outlet water chamber, and then flows out from the outlet nozzle of the lower head and is transported back to the reactor by the reactor coolant pump. The partition divides the steam generator into an inlet and an outlet water chamber. The water chambers are covered by tube sheets, and both ends of the heat exchanger tubes are fastened through the tube sheets. On the secondary side of the steam generator, the outside of the U-shaped heat transfer tubes is supported by many horizontal support plates, and the U-shaped tubes pass through the holes of these support plates. There are small gaps between the heat transfer tubes, the holes of the support plates and the tube sheets. During the long-term operation of the nuclear power plant, impurities in the water precipitate and accumulate in these gap areas. These precipitates will eventually generate sludge and other debris, which will promote corrosion in the crack areas. If not repaired, it will eventually lead to tube rupture and radioactive water from the primary side flowing into the secondary side of the steam generator. The eddy current inspection system of the steam generator is used to detect the corrosion and wear conditions of the heat transfer tube wall. During the inspection process, it is necessary to insert and withdraw the eddy current probe in the high-radiation area of the steam generator. Since the radiation level in this area is relatively high, it is very necessary to minimize the number of personnel and time entering the steam generator room. Usually, the probe is connected to a long flexible tube, and the eddy current probe is driven by the probe pusher to pass through the flexible catheter to reach the inspection area. One end of the flexible catheter is usually fixed to the probe pusher, and the other end is connected to the probe locator. The probe locator moves on the steam generator tube sheet and checks the condition of the corresponding heat transfer tube by moving to different heat transfer tubes.

[0003] One problem during the eddy current inspection process is that as the probe locator moves to different positions of the heat transfer tubes, the length of the catheter in the steam generator needs to be increased or decreased. This step is usually completed by the staff entering the steam generator room to manually increase or decrease the flexible catheter part. This will increase the radiation dose exposure for the on-site staff and may increase the risk of internal irradiation. Summary of the Invention

[0004] The object of the present invention is to provide a conduit adjusting device for eddy current inspection of a steam generator, which can remotely adjust the length of the conduit.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a duct adjustment device for eddy current inspection of a steam generator, which comprises: a duct adjustment part, which is installed on the duct, and comprises a clamping assembly and a driving assembly. The clamping assembly can be clamped on the outer peripheral surface of the duct and drive the duct to move through the friction between the clamping assembly and the duct, and the driving assembly drives the clamping assembly to move, thereby driving the duct to move.

[0006] In another embodiment, the adjusting portion includes a mounting shell, the clamping assembly includes a first cam and a first guide wheel which are arranged in the mounting shell and are opposite to each other, the driving assembly is used to drive the first cam to rotate, an advance and retreat gap is formed between the first cam and the first guide wheel, an advance and retreat hole is opened on the mounting shell at a position opposite to the advance and retreat gap, and the shortest distance between the first cam and the first guide wheel is smaller than the diameter of the catheter in a free state.

[0007] In another embodiment, the driving assembly includes a driving motor installed in the mounting shell, a first camshaft rotatably connected to the mounting shell, a first bevel gear coaxial with and fixedly connected to the output shaft of the driving motor, and a second bevel gear coaxial with and fixedly connected to the first camshaft, wherein the first bevel gear and the second bevel gear are meshed and their axes are perpendicular.

[0008] In another embodiment, a first sensor for sensing the position of the first cam is provided below the first cam.

[0009] In another embodiment, the first cam and the first guide wheel are arranged on the left side of the driving assembly, the adjusting device includes a second cam and a second guide wheel arranged on the right side of the driving assembly, the driving assembly includes a driving motor, a worm gear transmission-connected to the driving motor, and turbines respectively connected to both ends of the worm gear, and each turbine is coaxially fixedly connected to the first cam and the second cam.

[0010] In another embodiment, the first cam and the second cam are symmetrically arranged on both sides of the driving assembly, and the first cam and the second cam respectively clamp or release their corresponding catheters simultaneously.

[0011] In another embodiment, the catheter comprises: an outer catheter; an inner catheter which is disposed inside the outer catheter and is capable of moving along the axial line direction of the outer catheter; an adjusting part which is mounted on the outer catheter and comprises a pressing component and a driving component, the pressing component can press on the outer peripheral surface of the inner catheter, and drives the inner catheter to move through the frictional force between it and the inner catheter and the outer catheter, and the driving component drives the pressing component to act, thereby driving the inner catheter to move.

[0012] In another embodiment, the pressing component comprises a first mounting ring slidably sleeved on the inner catheter, a second mounting ring coaxially and fixedly connected with the outer catheter and sleeved on the inner catheter, and a first airbag. An annular first mounting groove is arranged on the inner peripheral surface of the first mounting ring along its circumferential direction, the first airbag is arranged in the first mounting groove, the driving component comprises a cylinder with the cylinder body fixed on the first mounting ring and the piston rod fixed on the second mounting ring. When the first airbag is inflated and bulges, it clamps the inner catheter, the cylinder extends, driving the first mounting ring and the second mounting ring to separate, thereby enabling the inner catheter to extend out of the outer catheter. When the first airbag deflates and contracts, the first airbag releases the inner catheter, the cylinder shortens, driving the first mounting ring to approach the second mounting ring and return to the initial position. In this way, the inner catheter gradually extends out of the outer catheter, and vice versa, the inner catheter gradually retracts into the outer catheter.

[0013] In another embodiment, an annular second mounting groove is arranged on the inner peripheral surface of the second mounting ring along its circumferential direction, the pressing component comprises a second airbag, the second airbag is arranged in the second mounting groove. When the inner catheter extends to the required length, the second airbag and the first airbag remain inflated, achieving the effect of locking the inner catheter.

[0014] In another embodiment, the cylinder comprises a cylinder body, a piston and a piston rod. The piston divides the interior of the cylinder body into a first chamber and a second chamber. One end of the piston rod is disposed in the second chamber and is coaxially and fixedly connected with the piston. The cylinder body is provided with a first air supply pipe for introducing gas into the first chamber.

[0015] In another embodiment, a first air inlet channel communicating with the first airbag is arranged at the front end of the cylinder body. When gas is introduced into the first chamber, the gas in the second chamber is squeezed into the first airbag. While the piston rod extends, the first airbag expands and bulges. When the gas in the first chamber is released, the gas in the first airbag enters the second chamber, and the first airbag deflates and contracts.

[0016] In another embodiment, the end of the piston rod connected to the piston is its rear end. A second air inlet passage for introducing the gas in the second chamber into the second airbag is provided in the piston rod. The two passage openings of the second air inlet passage are a first passage opening and a second passage opening respectively. The first passage opening is located on the circumferential surface of the rear end of the piston rod, and the second passage opening is located on the circumferential surface of its front end and is communicated with the second airbag through a connecting pipe.

[0017] In another embodiment, when the piston rod extends to the limit position, the first passage opening is sealed by the front end of the cylinder block, maintaining the pressure stability in the second airbag, and thus ensuring the sealing stability of the second airbag for the inner conduit.

[0018] In another embodiment, a first distribution air passage is formed in the first mounting ring. The first distribution air passage includes a first main air passage arranged in a ring shape, a first outer air passage connected between the cylinder and the first main air passage, and a plurality of first inner air passages diverging in a ring shape. All the first inner air passages are centrosymmetric about the axis of the first mounting ring. The first airbag is in a ring shape when inflated, and a plurality of first connecting nozzles respectively corresponding to the first inner air passages are formed on its outer circumferential surface. The pressing assembly includes a first hose connected between the first inner air passage and the first connecting nozzle.

[0019] In another embodiment, a second distribution air passage is formed in the second mounting ring. The second distribution air passage includes a second main air passage arranged in a ring shape, a second outer air passage connected between the cylinder and the second main air passage, and a plurality of second inner air passages diverging in a ring shape. All the second inner air passages are centrosymmetric about the axis of the second mounting ring. The second airbag is in a ring shape when inflated, and a plurality of second connecting nozzles respectively corresponding to the second inner air passages are formed on its outer circumferential surface. The second airbag includes a second hose connected between the second inner air passage and the second connecting nozzle.

[0020] In another embodiment, a first control valve is provided on the first air inlet passage. During inflation, the first control valve is opened. When the internal pressure reaches the set value after the first airbag bulges, the first control valve is closed to keep the first airbag in a bulged state.

[0021] In another embodiment, a second air inlet passage is provided on the piston rod. A second control valve is provided on the second air inlet passage. During inflation, the second control valve is opened. When the internal pressure reaches the set value after the second airbag bulges, the second control valve is closed to keep the second airbag in a bulged state.

[0022] In another embodiment, the end of the piston rod connected to the piston is its rear end. A second air inlet passage for introducing the gas in the second chamber into the second airbag is provided in the piston rod. The two passage openings of the second air inlet passage are a first passage opening and a second passage opening respectively. The first passage opening is located on the circumferential surface of the rear end of the piston rod, and the second passage opening is located on the circumferential surface of its front end and is connected to the second airbag through a connecting pipe.

[0023] The present invention also provides an adjustment method based on the above-mentioned conduit adjustment device for eddy current inspection of a steam generator. The control method includes the following steps:

[0024] A. When it is necessary to extend the conduit, inflate the first airbag. The gas enters the first airbag from different positions of the first airbag through the first distribution air passage at the same time, so that the inner ring of the first airbag expands uniformly and clamps the inner conduit, ensuring that there is close contact and no relative sliding between the first airbag and the inner conduit. The second airbag deflates and contracts, and it can slide relative to the inner conduit;

[0025] B. Control the cylinder to extend, thereby driving the second mounting ring away from the first mounting ring, that is, extending the inner conduit out of the outer conduit;

[0026] C. After the inner conduit extends to the set position, inflate the second airbag. The gas enters the second airbag from different positions of the second airbag through the second distribution air passage at the same time, so that the inner ring of the second airbag expands uniformly and clamps the inner conduit, ensuring that there is close contact and no relative sliding between the second airbag and the inner conduit; then open the first distribution air passage, control the first airbag to deflate and contract, so that the first airbag has no clamping force on the inner conduit, and the first airbag can slide relative to the inner conduit;

[0027] D. Control the cylinder to retract. At this time, the relative positions of the inner and outer conduits remain unchanged, and the first mounting ring approaches the second mounting ring to return to the initial state of step A;

[0028] E. Repeat steps B-D until the outer conduit extends to the required position.

[0029] The beneficial effects of the present invention are as follows: While driving the cam to press the conduit through the driving mechanism, the friction force between the cam and the conduit or the friction force between the airbag and the conduit is used to drive the conduit to move, which can realize the remote control of the conduit and avoid the irradiation of personnel dosage; The first distribution air passage and the second distribution air passage can ensure the stable clamping of the conduit by the pneumatic control structure during the conveying process and prevent slipping, thereby ensuring the conveying efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic diagram of the principle of Embodiment 1;

[0031] Figure 2 is Figure 1 a cross-sectional view of;

[0032] Figure 3 Schematic diagram of the principle of Embodiment 2;

[0033] Figure 4 Schematic diagram of the principle of Embodiment 3;

[0034] Figure 5 Schematic diagram of the principle of Embodiment 4 (cylinder shortened state);

[0035] Figure 6 Schematic diagram of the principle of Embodiment 4 (cylinder extended state);

[0036] Figure 7 Schematic diagram of the structure of the first mounting ring and the first airbag in Embodiment 4 (when the first airbag is not inflated);

[0037] Figure 8 Schematic diagram of the structure of the first mounting ring and the first airbag in Embodiment 4 (when the first airbag is inflated);

[0038] Figure 9 Schematic diagram of the structure of the second mounting ring and the second airbag in Embodiment 4 (when the second airbag is not inflated). Detailed implementation manners

[0039] The following provides a detailed description of the present invention in conjunction with the embodiments shown in the drawings:

[0040] The catheter adjusting device for eddy current inspection of a steam generator includes: an outer catheter, an inner catheter, and an adjusting part. The inner catheter passes through the outer catheter and can move along the axial line direction of the outer catheter; the adjusting part is installed on the outer catheter, and it includes a pressing component and a driving component. The pressing component can press against the outer peripheral surface of the inner catheter and drive the inner catheter to move through the frictional force between it and the inner catheter. The driving component drives the pressing component to act, thereby driving the inner catheter to move forward or backward.

[0041] Specifically, the pressing component and the driving component can be realized through the following embodiments:

[0042] Embodiment 1

[0043] As Figure 1-2As shown, when only a single conduit 13 needs to be driven, the conduit adjustment device for eddy current inspection of a steam generator includes a mounting housing 0, a first cam 1 and a first guide wheel 2 as a clamping assembly, and a driving assembly for driving the first cam 1 to rotate. The first cam 1 and the first guide wheel 2 are arranged in the mounting housing 0, and there are multiple first guide wheels 2. An advance and retreat gap is formed between the first cam 1 and the first guide wheel 2. An advance and retreat hole 3 is provided on the mounting housing 0 at a position opposite to the advance and retreat gap. The shortest distance between the first cam 1 and the first guide wheel 2 is smaller than the diameter of the conduit 13 in a free state. The driving assembly includes a driving motor 4 installed in the mounting housing 0, a first camshaft 5 rotatably connected to the mounting housing 0, a first bevel gear 6 coaxial with and fixedly connected to the output shaft of the driving motor 4, and a second bevel gear 7 coaxial with and fixedly connected to the first camshaft 5. The first bevel gear 6 and the second bevel gear 7 are meshed and the axes are perpendicular. A first sensor 8 for sensing the position of the first cam 1 is provided below the first cam 1.

[0044] Embodiment 2

[0045] like Figure 3 As shown, when two conduits need to be driven, the conduit adjustment device for eddy current inspection of steam generator includes a mounting housing 0, a first cam 1 and a first guide wheel 2 as a clamping assembly, and a driving assembly for driving the first cam 1 to rotate. The first cam 1 and the first guide wheel 2 are arranged in the mounting housing 0. There are multiple first guide wheels 2. An advance and retreat gap is formed between the first cam 1 and the first guide wheel 2. An advance and retreat hole 3 is opened on the mounting housing 0 and at a position opposite to the advance and retreat gap. The shortest distance between the first cam 1 and the first guide wheel 2 is less than the diameter of the conduit in the free state. A first sensor 8 for sensing the position of the first cam 1 is provided below the first cam 1. The first cam 1 and the first guide wheel 2 are arranged on the left side of the driving assembly. The adjustment device includes a second cam 9 and a second guide wheel 10 arranged on the right side of the driving assembly. The driving assembly includes a driving motor 4, a worm 11 connected to the driving motor 4, and turbines 12 respectively connected to the two ends of the worm 11. Each turbine 12 is coaxially fixedly connected to the first cam 1 and the second cam 9. The first cam 1 and the second cam 9 are symmetrically arranged on both sides of the driving assembly, and the first cam 1 and the second cam 9 clamp or release their corresponding conduits 13 simultaneously.

[0046] The principle of the above embodiments is to drive the cam to press the catheter through the driving mechanism and drive the catheter to move through the friction between the cam and the catheter, so as to realize remote control of the catheter. For double catheters, it should be noted that the installation directions of the two cams should be opposite, that is, clamp the catheter at the same time or keep the catheter in a relaxed state at the same time.

[0047] Embodiment III

[0048] As shown in Figure 4 , the device includes: an outer catheter 14, an inner catheter 15, and an adjusting part. The adjusting part includes a pressing component and a driving component. The pressing component includes a first mounting ring 16 slidably sleeved on the inner catheter 15, and a second mounting ring 17 coaxially fixed to the outer catheter 14 and sleeved on the inner catheter 15. An annular first mounting groove 19 is provided on the inner peripheral surface of the first mounting ring 16 along its circumference, and a first airbag 18 is arranged in the first mounting groove 19. The driving component includes a cylinder 20 with a cylinder body 28 fixed on the first mounting ring 16 and a piston rod 26 fixed on the second mounting ring 17. When the first airbag 18 is inflated and bulges, the inner catheter 15 is clamped. The cylinder 20 extends, driving the first mounting ring 16 and the second mounting ring 17 to separate, and then the inner catheter 15 extends out of the outer catheter 14. When the first airbag 18 deflates and contracts, the first airbag 18 releases the inner catheter 15, the cylinder 20 shortens, driving the first mounting ring 16 to approach the second mounting ring 17 and return to the initial position. In this way, the inner catheter 15 gradually extends out of the outer catheter 14, and vice versa, the inner catheter 15 gradually retracts into the outer catheter 14. An annular second mounting groove 22 is provided on the inner peripheral surface of the second mounting ring 17 along its circumference. The pressing component includes a second airbag 21, and the second airbag 21 is arranged in the second mounting groove 22.

[0049] Based on the adjustment method of the above-mentioned catheter adjustment device for eddy current inspection, the control method includes the following steps:

[0050] A1. When the catheter needs to be extended, inflate the first airbag to make the inner circle of the first airbag expand evenly and clamp the inner catheter, ensuring that there is a tight fit between the first airbag and the inner catheter without relative sliding. The second airbag deflates and contracts, and it can slide relative to the inner catheter;

[0051] B1. Control the cylinder to extend, thereby driving the second mounting ring away from the first mounting ring, that is, making the inner catheter extend out of the outer catheter;

[0052] C1. After the inner catheter extends to the set position, inflate the second airbag to make the inner circle of the second airbag expand evenly and clamp the inner catheter, ensuring that there is a tight fit between the second airbag and the inner catheter without relative sliding; then control the first airbag to deflate and contract, so that the first airbag has no clamping force on the inner catheter, and the first airbag can slide relative to the inner catheter;

[0053] D1. Control the cylinder to retract. At this time, the relative positions of the inner and outer catheters remain unchanged, and the first mounting ring approaches the second mounting ring and returns to the initial state of step A;

[0054] E1. Repeat steps B1 - D1 until the outer catheter extends to the required position.

[0055] Embodiment IV

[0056] As shown Figure 5-6 in the figure, the device includes an outer catheter 14, an inner catheter 15, and an adjusting part. The adjusting part includes a pressing component and a driving component. The pressing component includes a first mounting ring 16 slidably sleeved on the inner catheter 15, and a second mounting ring 17 coaxially fixed with the outer catheter 15 and sleeved on the inner catheter 15. An annular first mounting groove 19 is provided on the inner peripheral surface of the first mounting ring 16 along its circumferential direction. A first airbag 18 is arranged in the first mounting groove 19. The driving component includes a cylinder 20 with a cylinder block 28 fixed on the first mounting ring 16 and a piston rod 26 fixed on the second mounting ring 17. When the first airbag 18 is inflated and bulges, the inner catheter 15 is clamped. The cylinder 20 extends, driving the first mounting ring 16 and the second mounting ring 17 to separate, and further causing the inner catheter 15 to extend out of the outer catheter 14. When the first airbag 18 deflates and contracts, the first airbag 18 releases the inner catheter 15, the cylinder 20 shortens, driving the first mounting ring 16 to approach the second mounting ring 17 and return to the initial position. In this way, the inner catheter 15 gradually extends out of the outer catheter 14, and vice versa, the inner catheter 15 gradually retracts into the outer catheter 14. An annular second mounting groove 22 is provided on the inner peripheral surface of the second mounting ring 17 along its circumferential direction. The pressing component includes a second airbag 21, and the second airbag 21 is arranged in the second mounting groove 22. The first mounting ring 16 and the second mounting ring 17 are sleeved on the inner catheter 15, and the second mounting ring 17 is coaxially fixedly connected with the outer catheter 14.

[0057] Among them, as Figure 7-9 shown in the figure, a first distribution air duct 161 is formed inside the first mounting ring 16. The first distribution air duct 161 includes a first main air duct 161A in an annular shape, a first outer air duct 161B connecting between the cylinder 20 and the first main air duct 161A, and a plurality of first inner air ducts 161C diverging in an annular shape. All the first inner air ducts 161C are centrosymmetric about the axis of the first mounting ring 16. When the first airbag 18 is in an inflated state, it is in an annular shape, and a plurality of first connecting nozzles 31 respectively corresponding to the first inner air ducts 161C are formed on its outer peripheral surface. The first airbag 18 includes a first hose 32 connecting between the first inner air duct 161C and the first connecting nozzle 31. The second mounting ring 17 has the same internal structure as the first mounting ring 16. A second distribution air duct 171 is formed inside the second mounting ring 17. The second distribution air duct 171 includes a second main air duct 171A in an annular shape, a second outer air duct 171B connecting between the cylinder 20 and the second main air duct 171A, and a plurality of second inner air ducts 171C diverging in an annular shape. All the second inner air ducts 171C are centrosymmetric about the axis of the second mounting ring 17. When the second airbag 21 is in an inflated state, it is in an annular shape, and a plurality of second connecting nozzles 41 respectively corresponding to the second inner air ducts 171C are formed on its outer peripheral surface. The second airbag 21 includes a second hose 42 connecting between the second inner air duct 171C and the second connecting nozzle 41.

[0058] The cylinder 20 includes a cylinder block 28, a piston 25 and a piston rod 26. The piston 25 divides the interior of the cylinder block into a first chamber A and a second chamber B. One end of the piston rod 26 is disposed in the second chamber B and is fixedly connected to the piston 25 coaxially. A first air supply pipe 54 for introducing gas into the first chamber A is provided on the cylinder block 28; a first air intake passage 55 communicating with the first distribution air passage 161 of the first airbag 18 is provided at the front end of the cylinder block. When gas is introduced into the first chamber A, the gas in the second chamber B is squeezed into the first airbag 18. While the piston rod 26 extends, the first airbag 18 expands and bulges to clamp the inner conduit 15. When the gas in the first chamber is released, the gas in the first airbag 18 enters the second chamber, and the first airbag 18 deflates and contracts, releasing the inner conduit 15. There is no need to separately provide a gas supply pipeline for the first airbag 18, which simplifies the structure of the device and reduces the risk of parts loosening and falling due to complex structure.

[0059] To facilitate the control of the inflation and deflation of the airbag, a first control valve 56 is provided on the first air intake passage 55. During inflation, the first control valve 56 is opened. When the internal pressure of the first airbag 18 reaches the set value after bulging, the first control valve 56 is closed to keep the first airbag 18 in a bulged state; a second air intake passage 57 is provided on the piston rod 26, and a second control valve 58 is provided on the second air intake passage 57. During inflation, the second control valve 58 is opened. When the internal pressure of the second airbag 21 reaches the set value after bulging, the second control valve 58 is closed to keep the second airbag 21 in a bulged state. At this time, the piston rod 26 of the cylinder 20 continues to extend, driving the inner conduit 15 to extend out of the outer conduit 14.

[0060] The end of the piston rod 26 connected to the piston 21 is its rear end. A second air intake passage 57 for introducing the gas in the second chamber B into the second airbag 21 is provided inside the piston rod 26. The two passage openings of the second air intake passage 57 are respectively a first passage opening 27A and a second passage opening 27B. The first passage opening 27A is located on the circumferential surface of the rear end of the piston rod, and the second passage opening 27B is located on the circumferential surface of its front end and is connected to the second airbag 21 through a connecting pipe. The second passage opening 27B communicates with the second distribution air passage 171.

[0061] Based on the adjustment method of the above-mentioned conduit adjustment device for steam generator eddy current inspection, the control method includes the following steps:

[0062] A2. When it is necessary to extend the conduit, open the first control valve 56, close the second control valve 58, the cylinder extends, and the piston presses part of the gas in the second chamber B into the first airbag, so that the inner ring of the first airbag expands evenly and clamps the inner conduit, ensuring that there is a tight fit between the first airbag and the inner conduit without relative sliding. At this time, close the first control valve 56, and the second control valve 58 remains closed. The second airbag is in a contracted state and can slide relative to the inner conduit;

[0063] B2. The air cylinder continues to extend, thereby driving the second mounting ring away from the first mounting ring, and even extending the inner conduit out of the outer conduit;

[0064] C2. The air cylinder extends a certain distance, and the conduit extends a corresponding distance. Then, keep the first control valve closed and open the second control valve. The air cylinder continues to extend a certain distance, so that part of the gas in the second cavity is pressed into the second airbag, causing the inner ring of the second airbag to expand evenly and clamp the inner conduit, ensuring that there is a tight fit between the second airbag and the inner conduit without relative sliding. Then, open the first control valve, and the compressed gas in the first airbag enters the second cavity through the first distribution air passage and the first intake passage;

[0065] D2. Then, control the air cylinder to contract, and the first airbag deflates and contracts accordingly, so that the first airbag has no clamping force on the inner conduit. At this time, the first mounting ring moves towards the second mounting ring along with the cylinder block of the air cylinder and returns to the initial position;

[0066] E2. Repeat steps B2 - D2 until the outer conduit extends to the required position.

[0067] When retraction is required, just operate in the reverse direction. Adding the first control valve, the second control valve, the first intake passage, and the second intake passage can eliminate the equipment for supplying gas to the first airbag and the second airbag, further streamlining the structure of the device and further reducing the risk of parts loosening and falling caused by the complex structure.

[0068] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of this patent and implement it accordingly. It is not intended to limit the protection scope of this patent. All equivalent changes or modifications made according to the spirit of this patent should be covered within the protection scope of this patent.

Claims

1. A catheter adjustment device for eddy current inspection of a steam generator, characterized in that, It includes: The catheter adjustment part is installed on the catheter and includes a clamping component and a driving component. The clamping component can be clamped on the outer peripheral surface of the catheter and drive the catheter to move through the friction between the clamping component and the catheter. The driving component drives the clamping component to move, thereby driving the catheter to move.

2. The catheter adjustment device for eddy current inspection of a steam generator according to claim 1, characterized in that: The adjusting portion includes a mounting shell, the clamping assembly includes a first cam and a first guide wheel which are arranged in the mounting shell and are opposite to each other, the driving assembly is used to drive the first cam to rotate, an advance and retreat gap is formed between the first cam and the first guide wheel, an advance and retreat hole is opened on the mounting shell at a position opposite to the advance and retreat gap, and the shortest distance between the first cam and the first guide wheel is smaller than the diameter of the catheter in a free state.

3. The catheter adjustment device for eddy current inspection of a steam generator according to claim 2, characterized in that: The driving assembly includes a driving motor installed in the mounting housing, a first camshaft rotatably connected to the mounting housing, a first bevel gear coaxial with and fixedly connected to the output shaft of the driving motor, and a second bevel gear coaxial with and fixedly connected to the first camshaft, wherein the first bevel gear and the second bevel gear are meshed and their axes are perpendicular.

4. The catheter adjustment device for eddy current inspection of a steam generator according to claim 2, characterized in that: A first sensor for sensing the position of the first cam is provided below the first cam.

5. The catheter adjustment device for eddy current inspection of a steam generator according to claim 4, characterized in that: The first cam and the first guide wheel are arranged on the left side of the driving assembly, the adjusting device includes a second cam and a second guide wheel arranged on the right side of the driving assembly, the driving assembly includes a driving motor, a worm gear transmission-connected to the driving motor, and turbines respectively connected to both ends of the worm gear, and each turbine is coaxially fixedly connected to the first cam and the second cam.

6. The catheter adjustment device for eddy current inspection of a steam generator according to claim 5, characterized in that: The first cam and the second cam are symmetrically arranged on both sides of the driving assembly, and the first cam and the second cam respectively clamp or release their corresponding catheters at the same time.

7. The catheter adjustment device for eddy current inspection of a steam generator according to claim 1, characterized in that, The catheter comprises: External catheter; An inner catheter, which is inserted into the outer catheter and can move along the axis of the outer catheter; The adjusting part is installed on the outer catheter and includes a clamping assembly and a driving assembly. The clamping assembly can be clamped on the outer peripheral surface of the inner catheter and drive the inner catheter to move through the friction between the clamping assembly and the inner catheter and the outer catheter. The driving assembly drives the clamping assembly to move, thereby driving the inner catheter to move.

8. The catheter adjustment device for eddy current inspection of a steam generator according to claim 7, characterized in that: The clamping assembly includes a first mounting ring slidably mounted on the inner catheter, a second mounting ring coaxially fixedly connected to the outer catheter and mounted on the inner catheter, and a first airbag. The inner circumferential surface of the first mounting ring is provided with an annular first mounting groove along its circumference. The first airbag is arranged in the first mounting groove. The driving assembly includes a cylinder with a cylinder body fixed on the first mounting ring and a piston rod fixed on the second mounting ring. When the first airbag is inflated and bulged, it clamps the inner catheter, and the cylinder extends to drive the first mounting ring and the second mounting ring to separate, thereby extending the inner catheter from the outer catheter. When the first airbag is deflated and contracted, the first airbag releases the inner catheter, and the cylinder shortens, driving the first mounting ring to approach the second mounting ring and return to the initial position. Such a cycle causes the inner catheter to gradually extend from the outer catheter.

9. The catheter adjustment device for eddy current inspection of a steam generator according to claim 8, characterized in that: An annular second mounting groove is provided on the inner circumferential surface of the second mounting ring along its circumferential direction. The pressing assembly includes a second airbag, and the second airbag is arranged in the second mounting groove. When the inner catheter extends to the required length, the second airbag and the first airbag remain inflated.

10. The catheter adjustment device for eddy current inspection of a steam generator according to claim 9, characterized in that: The cylinder includes a cylinder block, a piston, and a piston rod. The piston divides the interior of the cylinder block into a first chamber and a second chamber. One end of the piston rod is arranged in the second chamber and is fixedly connected to the piston coaxially. A first air supply pipe for introducing gas into the first chamber is provided on the cylinder block.

11. The catheter adjustment device for eddy current inspection of a steam generator according to claim 10, characterized in that: A first air inlet passage communicating with the first airbag is provided at the front end of the cylinder block. When gas is introduced into the first chamber, the gas in the second chamber is squeezed into the first airbag. While the piston rod extends, the first airbag expands and bulges. When the gas in the first chamber is released, the gas in the first airbag enters the second chamber, and the first airbag deflates and contracts.

12. The catheter adjustment device for eddy current inspection of a steam generator according to claim 11, characterized in that: The end of the piston rod connected to the piston is its rear end. A second air inlet passage for introducing the gas in the second chamber into the second airbag is provided in the piston rod. The two passage openings of the second air inlet passage are respectively a first passage opening and a second passage opening. The first passage opening is located on the circumferential surface of the rear end of the piston rod, and the second passage opening is located on the circumferential surface of its front end and is connected to the second airbag through a connecting pipe.

13. The catheter adjustment device for eddy current inspection of a steam generator according to claim 12, characterized in that: When the piston rod extends to the limit position, the first passage opening is sealed by the front end of the cylinder block.

14. The catheter adjustment device for eddy current inspection of a steam generator according to claim 11, characterized in that: A first distribution air passage is formed in the first mounting ring. The first distribution air passage includes a first main air passage arranged in a ring shape, a first outer air passage connected between the cylinder and the first main air passage, and a plurality of first inner air passages diverging in a ring shape. All the first inner air passages are centrosymmetric about the axis of the first mounting ring. The first airbag is annular in the inflated state, and a plurality of first connection nozzles respectively corresponding to the first inner air passages are formed on its outer circumferential surface. The pressing assembly includes a first hose connected between the first inner air passage and the first connection nozzle.

15. The catheter adjustment device for eddy current inspection of a steam generator according to claim 14, characterized in that: A second distribution air passage is formed in the second mounting ring. The second distribution air passage includes a second main air passage arranged in a ring shape, a second outer air passage connected between the cylinder and the second main air passage, and a plurality of second inner air passages diverging in a ring shape. All the second inner air passages are centrosymmetric about the axis of the second mounting ring. The second airbag is annular in the inflated state, and a plurality of second connection nozzles respectively corresponding to the second inner air passages are formed on its outer circumferential surface. The control structure includes a second hose connected between the second inner air passage and the second connection nozzle.

16. The catheter adjusting device for eddy current inspection of a steam generator according to claim 14, wherein: A first control valve is provided on the first air inlet passage. During inflation, the first control valve is opened. When the internal pressure of the first airbag reaches the set value after bulging, the first control valve is closed to keep the first airbag in the inflated state.

17. The catheter adjusting device for eddy current inspection of a steam generator according to claim 14, wherein: A second air inlet passage is provided on the piston rod, and a second control valve is provided on the second air inlet passage. During inflation, the second control valve is opened. When the internal pressure of the second airbag reaches the set value after bulging, the second control valve is closed to keep the second airbag in the inflated state.

18. The catheter adjusting device for eddy current inspection of a steam generator according to claim 14, wherein: The end of the piston rod connected to the piston is its rear end. A second air inlet passage for introducing the gas in the second chamber into the second airbag is provided in the piston rod. The two passage openings of the second air inlet passage are a first passage opening and a second passage opening respectively. The first passage opening is located on the circumferential surface of the rear end of the piston rod, and the second passage opening is located on the circumferential surface of its front end and is connected to the second airbag through a connecting pipe.

19. An adjusting method for a catheter adjusting device for eddy current inspection of a steam generator according to any one of claims 7-18, wherein the catheter comprises an inner catheter and an outer catheter sleeved outside the inner catheter, and the first mounting ring and the second mounting ring are sleeved on the inner catheter, and the second mounting ring is coaxially and fixedly connected to the outer catheter. The control method includes the following steps: A. When it is necessary to extend the catheter, inflate the first airbag. The gas enters the first airbag from different positions of the first airbag through the first distribution air passage at the same time, so that the inner ring of the first airbag expands uniformly and clamps the inner catheter, ensuring that there is close contact and no relative sliding between the first airbag and the inner catheter. The second airbag deflates and contracts, and it can slide relative to the inner catheter. B. Control the cylinder to extend, so as to drive the second mounting ring away from the first mounting ring, that is, to extend the inner catheter out of the outer catheter. C. After the inner catheter extends to the set position, inflate the second airbag. The gas enters the second airbag from different positions of the second airbag through the second distribution air passage at the same time, so that the inner ring of the second airbag expands uniformly and clamps the inner catheter, ensuring that there is close contact and no relative sliding between the second airbag and the inner catheter. Subsequently, open the first distribution air passage, control the first airbag to deflate and contract, so that the first airbag has no clamping force on the inner catheter, and the first airbag can slide relative to the inner catheter. D. Control the cylinder to retract. At this time, the relative positions of the inner and outer catheters remain unchanged, and the first mounting ring approaches the second mounting ring to return to the initial state of step A. E. Repeat steps B-D until the outer catheter extends to the required position.

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