Nuclear power station fuel assembly observation device

Abstract

The invention discloses a nuclear power station fuel assembly observation device, which belongs to the technical field of fuel assembly observation, is arranged in a transfer water tank provided with a fuel assembly, and comprises three observation mechanisms arranged in the transfer water tank; the observation mechanism comprises a long rod assembly, a support assembly and an observation assembly. The observation assembly comprises a support, a shielding cabin is rotationally arranged on the support, and a reflector is arranged at the position, corresponding to an observation window, of the shielding cabin. According to the scheme, the side face and the bottom face of the fuel assembly can be observed at the same time through the three observation mechanisms, the situation that an existing underwater camera is not comprehensive enough in observation is avoided, additional observation devices do not need to be designed, the use and observation cost is reduced, and the observation accuracy can be greatly improved; the mode that the camera directly observes the fuel assembly is avoided, the radiation resistance is high, the service life of the camera can be prolonged, the failure rate of the camera can be reduced, and the accuracy, reliability and safety of detection are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of fuel assembly observation, and more specifically to a nuclear power plant fuel assembly observation device. Background Art

[0002] The fuel assembly of a pressurized water reactor is the heart of a nuclear reactor and is responsible for generating the energy required for nuclear fission. Each fuel assembly is usually a rectangular frame structure consisting of a series of fuel rods, which are loaded with nuclear fuel and arranged in a tubular frame made of high-strength, corrosion-resistant materials. During the overhaul of the core and loading and unloading of nuclear power plants, a synchronous visual inspection of the surface of the nuclear fuel assembly is required to confirm that there are no foreign objects in the nuclear fuel assembly, no abnormalities in the lower tube seat, and the integrity of the nuclear fuel assembly.

[0003] At present, the appearance of nuclear fuel assemblies is usually inspected using a special radiation-resistant underwater camera installed in the nuclear fuel assembly transfer pool. However, the camera of the current radiation-resistant underwater camera is directly facing the fuel assembly. Due to long-term underwater work and high temperature, high radiation and high underwater pressure working environment, the radiation-resistant underwater camera has a short life and unstable performance and high failure rate. At the same time, the current underwater camera does not observe the fuel assembly comprehensively, which will directly affect the overhaul and loading and unloading period of the fuel assembly.

[0004] Therefore, it is necessary to provide a nuclear power plant fuel assembly observation device to solve the above technical problems. Summary of the invention

[0005] The purpose of the present invention is to provide a nuclear power plant fuel assembly observation device to solve the above technical problems.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] A nuclear power plant fuel assembly observation device is arranged in a transfer pool, wherein the transfer pool is provided with a fuel assembly, comprising:

[0008] An observation mechanism is disposed in the transfer pool and is provided with three of them, wherein two of the observation mechanisms are diagonally distributed and used to observe the side surface of the fuel assembly, and the other observation mechanism is used to observe the bottom surface of the fuel assembly;

[0009] The observation mechanism includes a long rod assembly, a bracket assembly and an observation assembly, one end of the long rod assembly is hung on the transfer pool, and the other end is connected to the bracket assembly, and the observation assembly is installed on the bracket assembly;

[0010] The observation component comprises a support, on which a shielding cabin is rotatably provided, an observation window is provided on one side of the shielding cabin and a camera is provided inside the cabin, and a reflector is provided at a position of the shielding cabin corresponding to the observation window.

[0011] Furthermore, the shielding cabin is an eccentric circle, a camera cabin is provided inside the shielding cabin, the camera is located in the camera cabin, and a rotating component for driving the camera cabin to rotate is provided on the support.

[0012] Furthermore, the rotating component includes:

[0013] A servo motor is arranged on the support, and a gear is arranged at the output end of the servo motor;

[0014] The outer gear ring is arranged on the outer wall of the camera cabin and meshes with the gear.

[0015] Furthermore, lighting lamps are provided on both sides of the reflector, the lighting lamps are connected to the shielding cabin, and the exterior of the servo motor is provided with a casing.

[0016] Furthermore, the bracket assembly includes a fixed bracket, a first joint and a base, the two ends of the fixed bracket are respectively connected to the first joint and the base, the first joint is connected to the long rod assembly, and the support is arranged on the base.

[0017] Furthermore, a support seat is also provided on the base, and a driving member that can drive the support to rotate is provided inside the support seat, and cable interfaces are provided on the support seat, the camera cabin and the casing.

[0018] Furthermore, the long rod assembly includes multiple hollow rods, one end of the hollow rod is connected to the second joint by a pin, and the other end is provided with an insertion rod, and a nut sleeve is threaded on the insertion rod. Adjacent hollow rods are connected by the cooperation of the pin and the second joint, and the insertion rod of the lowest hollow rod is connected to the first joint by a pin.

[0019] Furthermore, the second joint at the upper end of the uppermost hollow rod is connected to a connecting rod via a pin, and a lock buckle is installed on the connecting rod and a nut sleeve is threadedly connected.

[0020] Furthermore, a float is provided on one of the hollow rods.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. This solution can observe different positions of the fuel assembly through different angles of the reflectors on the observation mechanisms at different positions, that is, the side and bottom of the fuel assembly can be observed simultaneously through three observation mechanisms, avoiding the current situation that the underwater camera observation is not comprehensive enough, and there is no need to design additional observation devices for use, which reduces the cost of use and observation, thereby greatly improving the accuracy of observation and having strong practicality.

[0023] 2. The camera in this solution is protected inside the shielded cabin, avoiding the camera directly observing the fuel assembly. It has strong radiation resistance, which greatly reduces the impact of high temperature and high radiation on the camera, and can increase the service life of the camera and reduce its failure rate, ensuring the accuracy, reliability and safety of detection, and reducing the impact on the overhaul of the fuel assembly and the loading and unloading period.

[0024] 3. The shielding cabin in this scheme is an eccentric circle and is made of tungsten alloy. Therefore, when the reflector rotates, it will drive the thicker side of the shielding cabin tungsten alloy to rotate at the same time, so that the thicker side of the shielding cabin is always facing the fuel assembly, so that the radiation resistance is stronger and the camera is more radiation resistant.

[0025] 4. The rotating parts can drive the camera cabin, shielding cabin and reflector to rotate, so as to change the angle and orientation of the reflector. The suitable angle of the reflector can be adjusted according to specific observation needs. It is suitable for use in different situations and the adjustment is convenient and simple.

[0026] 5. In this solution, the driving member in the support seat can drive the support seat to rotate horizontally, thereby making the shielding cabin and the reflector rotate horizontally, so that the horizontal observation angle of the reflector can be adjusted according to actual needs, and the detection angle adjustment is richer and more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the three observation mechanisms in the present invention when observing the fuel assembly;

[0028] Figure 2 This is a schematic diagram of the top view of the three observation structures in the transfer pool observing the fuel assembly;

[0029] Figure 3 It is a structural schematic diagram of an observation mechanism for observing the bottom of a fuel assembly in the present invention;

[0030] Figure 4 for Figure 3 The enlarged structural diagram at A in the middle;

[0031] Figure 5 for Figure 3 The enlarged structural diagram at B in the middle;

[0032] Figure 6 It is a schematic diagram of the structure of the observation assembly on the support assembly of the present invention;

[0033] Figure 7 for Figure 6 The enlarged structural diagram at C in the middle;

[0034] Figure 8 for Figure 5 Schematic diagram of explosion state structure in;

[0035] Fig. 9 It is a schematic diagram of the three-dimensional structure of the hollow rod of the present invention;

[0036] Fig.10 for Fig. 9 The enlarged structural diagram at D in the middle;

[0037] Fig.11 It is a schematic diagram of the structure of the bracket assembly of the present invention;

[0038] Fig.12 It is a schematic diagram of the morphological structure of the observation assembly for observing the side of the fuel assembly in the present invention.

[0039] Description of the numbers in the figure:

[0040] 1. Transfer pool; 2. Fuel assembly; 3. Observation mechanism; 31. Long rod assembly; 311. Hollow rod; 312. Second joint; 313. Insert rod; 314. Nut sleeve; 32. Bracket assembly; 321. Fixed bracket; 322. First joint; 323. Base; 33. Observation assembly; 331. Support; 332. Shielding cabin; 333. Reflector; 4. Camera cabin; 5. Rotating part; 51. Servo motor; 52. Gear; 53. Outer gear ring; 6. Lighting lamp; 7. Support seat; 8. Connecting rod; 9. Lock; 10. Float. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] See also Figure 1-12A nuclear power plant fuel assembly observation device is arranged in a transfer pool 1. The transfer pool 1 is provided with a fuel assembly 2, including: an observation mechanism 3, which is arranged in the transfer pool 1 and is provided with three, wherein two observation mechanisms 3 are diagonally distributed for observing the side surfaces of the fuel assembly 2, and the other observation mechanism 3 is used to observe the bottom surface of the fuel assembly 2; the observation mechanism 3 includes a long rod assembly 31, a bracket assembly 32 and an observation assembly 33, one end of the long rod assembly 31 is suspended on the transfer pool 1, and the other end is connected to the bracket assembly 32, and the observation assembly 33 is installed on the bracket assembly 32; the observation assembly 33 includes a support 331, a shielding cabin 332 is rotatably provided on the support 331, an observation window is provided on one side of the shielding cabin 332 and a camera is provided inside the shielding cabin 332, and a reflector 333 is provided at the corresponding observation window of the shielding cabin 332.

[0043] When the three observation mechanisms 3 are placed in the transfer pool 1, the observation mechanisms 3 can be hung in the transfer pool 1 by connecting the industrial sling to the upper end of the long rod assembly 31 of the observation mechanism 3, and then fixing the industrial sling to the grid plate at the upper end of the transfer pool 1. Two of the observation mechanisms 3 are arranged diagonally, that is, the two observation mechanisms 3 are located at the side diagonals of the fuel assembly 2, such as Figure 1-2 The observation mechanism 3 is located at position a in order to observe the four sides of the fuel assembly 2; and the other observation mechanism 3 is located at other positions to observe the bottom surface of the fuel assembly 2, such as Figure 1-2 The b position in .

[0044] When observing the fuel assembly 2, the fuel assembly 2 at this time will be lifted by the lifting equipment and moved up and down to realize feeding and unloading, that is, first lift and remove multiple fuel assemblies 2, and then move the multiple fuel assemblies 2 down for feeding and loading after the unloading overhaul is completed. The camera in the shielding cabin 332 can observe the fuel assembly 2 under the reflection of the reflector 333. The angles of the shielding cabin 332 and the reflector 333 on the observation mechanism 3 at the two a positions are as shown in FIG. Figure 1 and Fig.12 As shown, at this time, the two observation mechanisms 3 at position a can fully observe the side of the fuel assembly 2; and the angles of the shielding cabin 332 and the reflector 333 on the observation mechanism 3 at position b are as shown in FIG. Figure 1 , Figure 3-4 and Figure 6 As shown, at this time, the bottom surface of the fuel assembly 2 is observed through the reflection of the reflector 333. Different positions of the fuel assembly 2 can be observed through different angles of the reflector 333 on the observation mechanism 3 at different positions, that is, the side and bottom of the fuel assembly 2 can be observed at the same time, avoiding the current situation that the underwater camera observation is not comprehensive enough, and there is no need to design another observation device for use, which reduces the cost of use and observation, and the observation of the fuel assembly 2 is more comprehensive, thereby greatly improving the accuracy of observation, and having strong practicality.

[0045] Moreover, the camera of the present application is protected inside the shielded cabin 332, and observes the fuel assembly 2 through the reflection of the observation window and the reflector 333 on the shielded cabin 332, avoiding the camera directly observing the fuel assembly 2. The shielded cabin 332 provides multi-layer radiation-resistant protection for the internal camera. The shielded cabin 332 is made of tungsten alloy, has strong radiation resistance, can be inspected close to the fuel assembly, has good observation effect underwater, and has a long working life. This greatly reduces the impact of high temperature and high radiation on the camera, can greatly improve the service life of the camera and reduce its failure rate, and reduce the impact on the overhaul of the fuel assembly and the loading and unloading period. At the same time, it can significantly improve the performance of the camera and ensure the accuracy, reliability and safety of the test results.

[0046] In this embodiment, preferably, please refer to Figure 4 , Figure 6 and Fig.12 , the shielding cabin 332 is an eccentric circle, and a camera cabin 4 is arranged inside the shielding cabin 332, and the camera is located inside the camera cabin 4. A rotating component 5 for driving the camera cabin 4 to rotate is arranged on the support 331. The camera cabin 4 is located in the shielding cabin 332 and is sealed by a sealing ring and a compression nut. Since the shielding cabin 332 is an eccentric circle, when the reflector 333 rotates, the thicker side of the tungsten alloy of the shielding cabin 332 will be driven to rotate at the same time, so that the thicker side of the shielding cabin 332 is always facing the fuel assembly 2, so that the radiation resistance is stronger, the use effect of the shielding cabin 332 is better, and the radiation resistance effect of the equipment is better, that is, the camera is better resistant to radiation. The rotating component 5 can drive the camera cabin 4 to rotate, that is, the shielding cabin 332 and the reflector 333 can be driven to rotate, so that the angle of the reflector 333 can be changed, that is, the side and bottom of the fuel assembly 2 can be observed through different angles of the reflector 333, and the appropriate angle of observation of the reflector 333 can be adjusted according to specific observation requirements, and the adjustment is convenient and simple.

[0047] In this embodiment, preferably, please refer to Figure 4 , Figure 6-7 and Fig.12 The rotating component 5 includes: a servo motor 51, which is arranged on the support 331, and a gear 52 is arranged at the output end of the servo motor 51; an outer gear ring 53, which is arranged on the outer wall of the camera cabin 4 and meshes with the gear 52. After the servo motor 51 is started, it will drive the gear 52 to rotate, and the gear 52 can drive the outer gear ring 53 and the camera cabin 4 to rotate, thereby driving the shielding cabin 332 and the reflector 333 to rotate. And the larger gear ratio of the gear 52 and the outer gear ring 53 can adjust the angle of the reflector 333 at a slower speed, so that the adjustment can be more accurate and stable.

[0048] In this embodiment, preferably, please refer to Figure 4 , Figure 6 and Fig.12 , lighting lamps 6 are provided on both sides of the reflector 333, and the lighting lamps 6 are connected to the shielding cabin 332. A casing is provided on the outside of the servo motor 51, and the lighting lamps 6 can illuminate the observation position of the fuel assembly 2 to improve the video inspection effect. The casing can protect the servo motor 51, and can be disassembled to facilitate the maintenance of the servo motor 51.

[0049] In this embodiment, preferably, please refer to Figure 3-4 and Figure 11-12 The bracket assembly 32 includes a fixed bracket 321, a first joint 322 and a base 323. The two ends of the fixed bracket 321 are respectively connected to the first joint 322 and the base 323. The first joint 322 is connected to the long rod assembly 31, and the support 331 is arranged on the base 323. The upper end of the fixed bracket 321 is connected to the long rod assembly 31 through the first joint 322, and the observation assembly 33 is also arranged on the base 323, so that it is more stable when used.

[0050] In this embodiment, preferably, please refer to Figure 4 , Figure 6 and Fig.12 A support seat 7 is also provided on the base 323. A driving member that can drive the support 331 to rotate is provided inside the support seat 7. Cable interfaces are provided on the support seat 7, the camera cabin 4 and the casing. The driving member in the support seat 7 may include a rotating motor and a worm gear device. The rotating motor drives the worm gear to rotate, thereby driving the support 331 to rotate horizontally, thereby causing the shielding cabin 332 and the reflector 333 to rotate horizontally, thereby adjusting the horizontal angle of the reflector 333, so that the horizontal observation angle of the reflector 333 can be adjusted according to actual needs, and the detection angle adjustment is more abundant and flexible. The cable interfaces are sealed by sealing rings and sealing pressure rings to ensure the sealing of the equipment.

[0051] In this embodiment, preferably, please refer to Figure 3-5 and Figure 8-11The long rod assembly 31 includes a plurality of hollow rods 311, one end of the hollow rod 311 is connected to the second joint 312 through a pin, and the other end is provided with an insert rod 313, and a nut sleeve 314 is threadedly connected to the insert rod 313. Adjacent hollow rods 311 are connected through the cooperation of the pin and the second joint 312, and the insert rod 313 of the bottom hollow rod 311 is connected to the first joint 322 through a pin. When two hollow rods 311 are connected, it is only necessary to insert one end of a hollow rod 311 with a nut sleeve 314 into the second joint 312 of another hollow rod 311, and after rotating, the nut sleeve 314 can be rotated with the cooperation of the pin to press and lock, so as to achieve the purpose of connecting and fixing the two hollow rods 311. Therefore, the number of hollow rods 311 can be adjusted according to the specific height requirements, which is convenient for observation at different depths, and has a wide range of applications and strong flexibility.

[0052] Similarly, after the bottom end of the lowest hollow rod 311 is inserted into the first joint 322 of the bracket assembly 32, the nut sleeve 314 can be rotated with the cooperation of the pin to fix it.

[0053] In this embodiment, preferably, please refer to Figure 3-5 and Figure 8 The second joint 312 at the upper end of the uppermost hollow rod 311 is connected to the connecting rod 8 through a pin, and the connecting rod 8 is installed with a lock buckle 9 and a nut sleeve 314 threadedly connected. After the connecting rod 8 is inserted into the second joint 312 of the uppermost hollow rod 311, the nut sleeve 314 can be fixed by rotating it with the cooperation of the pin, and after being fixed with the industrial sling and the lock buckle 9, the industrial sling is fixed to the grating plate at the upper end of the transfer tank 1, and the observation mechanism 3 can be hung in the transfer tank 1.

[0054] In this embodiment, preferably, please refer to Figure 1-3 , a floating ball 10 is disposed on one of the hollow rods 311. The floating ball 10 can provide a net buoyancy of less than about 5 kg of the entire device, making the entire device easy to control during installation and highly safe. The weight of the observation mechanism 3 during underwater installation can be reduced, making operation easier and improving safety.

[0055] It should be understood that the examples and implementation modes described herein are for illustrative purposes only and are not intended to limit the present invention. Those skilled in the art may make various modifications or changes based on the examples and implementation modes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0056] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, back, etc., then the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0057] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A nuclear power plant fuel assembly observation device, arranged in a transfer pool (1), wherein the transfer pool (1) is provided with a fuel assembly (2), characterized in that: include: An observation mechanism (3) is arranged in the transfer pool (1) and is provided with three members, wherein two of the observation mechanisms (3) are diagonally distributed and used to observe the side surface of the fuel assembly (2), and the other observation mechanism (3) is used to observe the bottom surface of the fuel assembly (2); The observation mechanism (3) comprises a long rod assembly (31), a bracket assembly (32) and an observation assembly (33); one end of the long rod assembly (31) is suspended on the transfer pool (1), and the other end is connected to the bracket assembly (32); and the observation assembly (33) is installed on the bracket assembly (32); The observation assembly (33) comprises a support (331), a shielding cabin (332) is rotatably provided on the support (331), an observation window is provided on one side of the shielding cabin (332) and a camera is provided inside the shielding cabin (332), and a reflector (333) is provided at a position corresponding to the observation window of the shielding cabin (332).

2. A nuclear power plant fuel assembly observation device according to claim 1, characterized in that: The shielding cabin (332) is an eccentric circle, a camera cabin (4) is provided inside the shielding cabin (332), the camera is located inside the camera cabin (4), and a rotating component (5) for driving the camera cabin (4) to rotate is provided on the support (331).

3. A nuclear power plant fuel assembly observation device according to claim 2, characterized in that: The rotating component (5) comprises: A servo motor (51) is arranged on the support (331), and a gear (52) is arranged at the output end of the servo motor (51); An outer gear ring (53) is arranged on the outer wall of the camera cabin (4) and meshes with the gear (52).

4. A nuclear power plant fuel assembly observation device according to claim 3, characterized in that: Illuminating lamps (6) are provided on both sides of the reflector (333), and the illuminating lamps (6) are connected to the shielding cabin (332). The exterior of the servo motor (51) is provided with a casing.

5. A nuclear power plant fuel assembly observation device according to claim 4, characterized in that: The support assembly (32) comprises a fixed support (321), a first joint (322) and a base (323); two ends of the fixed support (321) are respectively connected to the first joint (322) and the base (323); the first joint (322) is connected to the long rod assembly (31); and the support (331) is arranged on the base (323).

6. A nuclear power plant fuel assembly observation device according to claim 5, characterized in that: A support seat (7) is also provided on the base (323), and a driving member capable of driving the support seat (331) to rotate is provided inside the support seat (7), and cable interfaces are provided on the support seat (7), the camera cabin (4) and the housing.

7. A nuclear power plant fuel assembly observation device according to claim 5, characterized in that: The long rod assembly (31) includes a plurality of hollow rods (311), one end of each hollow rod (311) is connected to a second joint (312) via a pin, and the other end is provided with an insertion rod (313), a nut sleeve (314) is threadedly connected to the insertion rod (313), adjacent hollow rods (311) are connected via the cooperation of the pin and the second joint (312), and the insertion rod (313) of the lowest hollow rod (311) is connected to the first joint (322) via a pin.

8. A nuclear power plant fuel assembly observation device according to claim 7, characterized in that: The second joint (312) at the upper end of the uppermost hollow rod (311) is connected to a connecting rod (8) via a pin, and a lock buckle (9) and a nut sleeve (314) are installed on the connecting rod (8).

9. A nuclear power plant fuel assembly observation device according to claim 8, characterized in that: A floating ball (10) is provided on one of the hollow rods (311).

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