Quick assembly and disassembly and centering fixture for fuel assembly seismic test

Abstract

This utility model discloses a quick assembly, disassembly, and centering fixture for seismic testing of fuel assemblies, including a processing table. The upper part of the processing table has four sets of moving slots, and a moving box is slidably connected inside each moving slot. A connecting block is slidably connected inside each moving box. A clamping plate is fixedly connected to the upper part of each connecting block. Connecting boxes are fixedly connected to the lower two sides of each moving box. A guide rod is fixedly connected inside each connecting box. A first lug is slidably connected to the outer side of each guide rod. The first lug is fixedly connected to the lower two sides of the connecting block. A first spring is fixedly connected between the first lug and the moving box. A lifting slot is formed in the middle of the clamping plate and the connecting block. A positioning block is slidably connected inside the lifting slot. A positioning hole matching the positioning block is formed in the lower middle part of the moving box. This fixture can cover seismic testing requirements of different intensities and frequencies, improving the equipment's adaptability to diverse testing conditions.

Description

Technical Field

[0001] This utility model relates to the technical field of nuclear fuel assembly testing equipment, specifically a quick assembly, disassembly and alignment clamp for seismic testing of fuel assemblies. Background Technology

[0002] Seismic testing of fuel assemblies is a critical safety verification step before nuclear reactor fuel assemblies leave the factory and during operation and maintenance. Its core purpose is to simulate the vibration conditions that fuel assemblies may encounter throughout their entire life cycle (such as earthquakes, reactor equipment vibration, transportation bumps, etc.), verify their structural integrity and stability, avoid safety risks such as fuel rod deformation, grid loosening, and radioactive material leakage caused by vibration, and ensure the safe operation of nuclear reactors.

[0003] Existing clamping methods for fuel assembly seismic testing are limited and have poor adaptability: they only have a single clamping mode, either flexible clamping, which can increase the vibration frequency but cannot cope with high-intensity vibration; or rigid clamping, which is stable but cannot increase the vibration, and cannot cover the full range of working conditions for testing, including "low-frequency small amplitude" and "high-frequency large amplitude". Utility Model Content

[0004] The purpose of this invention is to provide a quick assembly, disassembly, and alignment fixture for seismic testing of fuel assemblies, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a quick assembly / disassembly and centering fixture for seismic testing of fuel assemblies, comprising a processing table, four sets of moving slots on the upper part of the processing table, a moving box slidably connected inside the moving slots, a connecting block slidably connected inside the moving box, a clamping plate fixedly connected to the upper part of the connecting block, connecting boxes fixedly connected to the lower two sides of the moving box, a guide rod fixedly connected inside the connecting box, a first lug slidably connected to the outer side of the guide rod, the first lug being fixedly connected to the lower two sides of the connecting block, a first spring fixedly connected between the first lug and the moving box, the first spring being sleeved on the outer side of the guide rod, a lifting slot is provided in the middle of the clamping plate and the connecting block, a positioning block is slidably connected inside the lifting slot, and a positioning hole for cooperating with the positioning block is provided in the lower middle part of the moving box.

[0006] Preferably, two sets of second lugs are fixedly connected to the lower sides of the movable box, a connecting frame is fixedly connected to the lower part of the processing table, a motor is fixedly connected to the front and right sides of the connecting frame, a threaded rod is fixedly connected to the power end of the motor through the connecting frame, the other end of the threaded rod is rotatably connected to the inner wall of the connecting frame, the two sets of threaded rods are staggered vertically, and the threaded rod is threadedly connected to the inside of the second lug.

[0007] Preferably, a connecting groove communicating with the lifting groove is provided on the opposite side of the clamping plates, and a pulling plate is fixedly connected to the upper part of the positioning block, and the pulling plate is slidably connected inside the lifting groove.

[0008] Preferably, a locking hole is provided on the inner side of the upper part of the clamping plate, and a locking rod that matches the locking hole is slidably connected inside the pulling plate.

[0009] Preferably, the pull plate has a control groove inside, a fixing ring is fixedly connected to the outside of the locking rod, the fixing ring is slidably connected inside the control groove, a second spring is fixedly connected between the fixing ring and the inner wall of the control groove, the second spring is sleeved on the outside of the locking rod, and a control piece is fixedly connected to one end of the locking rod through the pull plate.

[0010] Preferably, the clamps are fixedly connected to each other on one side with rubber pads.

[0011] Compared with the prior art, the beneficial effects of this utility model are: 1. Under normal conditions, the first spring pushes the first lug to slide along the guide rod, causing the connecting block and clamping plate to apply a flexible clamping force towards the assembly. During the test, the first spring can extend and retract with the vibration, adapting to real vibration conditions with low frequency and small amplitude. When high-frequency and high-amplitude high-intensity vibration is required, it is only necessary to push the pull plate to insert the positioning block into the positioning hole of the moving box, which can rigidly fix the connecting block and the moving box, and lock the clamping plate in a rigid clamping state. The two clamping modes do not require disassembly or replacement of the clamps and can be quickly switched by inserting and removing the positioning block. It can cover the vibration resistance test requirements of different intensities and frequencies, and improve the adaptability of the equipment to diverse test conditions. 2. This utility model also utilizes a centering and clamping drive structure consisting of a motor, a threaded rod, and a moving box. The motor drives the threaded rod to rotate via a key connection, causing the second lug and the moving box to slide along the moving groove of the processing table, achieving synchronous bidirectional movement of the four sets of clamping plates in the front, back, left, and right directions. This eliminates the need for manual bolt tightening and repeated adjustments during assembly and disassembly, significantly simplifying the operation process. Simultaneously, the motor's built-in encoder precisely controls the movement distance, and the gap between the moving groove and the moving box provides guidance, avoiding visual errors associated with manual centering. This ensures precise alignment of the fuel assembly axis with the test equipment axis, providing an accurate load transfer basis for seismic testing and guaranteeing the validity and reference value of the test data. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional structural cross-sectional view of the present invention; Figure 3 This is a three-dimensional structural cross-sectional view of the present invention; Figure 4This is an enlarged view of the structure at point A of this utility model.

[0013] In the diagram: 1. Processing table; 2. Moving slot; 3. Moving box; 4. Connecting box; 5. Connecting block; 6. Clamping plate; 7. First lug; 8. Guide rod; 9. First spring; 10. Positioning hole; 11. Lifting slot; 12. Positioning block; 13. Connecting slot; 14. Pulling plate; 15. Second lug; 16. Threaded rod; 17. Connecting frame; 18. Motor; 19. Rubber pad; 20. Locking rod; 21. Locking hole; 22. Control slot; 23. Fixing ring; 24. Second spring; 25. Control plate. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] Please see Figure 1-4 This utility model provides a technical solution: a quick assembly / disassembly and centering fixture for seismic testing of fuel assemblies, including a processing table 1. The processing table 1 has four symmetrically distributed moving slots 2 on its upper part. Moving boxes 3 are slidably connected to the inside of the moving slots 2 via clearance fit. Connecting blocks 5 are slidably connected to the inside of the moving boxes 3 via clearance fit. A clamping plate 6 is fixedly connected to the upper part of the connecting blocks 5 by screws. Connecting boxes 4 are fixedly connected to the lower sides of the moving boxes 3 via welding. Guide rods 8 are fixedly connected to the inside of the connecting boxes 4 via welding. First lugs 7 are slidably connected to the outer sides of the guide rods 8 via clearance fit. The first lugs 7 are fixedly connected to the lower sides of the connecting blocks 5 via welding and slide synchronously with the connecting blocks 5. The two sides of the first lugs 7 are flush with the inner wall of the moving boxes 3. A first spring 9 is fixedly connected by spot welding. The first spring 9 is sleeved on the outside of the guide rod 8. Under normal conditions, it pushes the first lug 7, connecting block 5, and clamping plate 6 to move towards the component, forming a flexible clamping force. During the seismic test, the first spring 9 can extend and retract with the vibration, aggravating the vibration frequency of the component and simulating the real vibration condition. A through lifting groove 11 is opened in the middle of the clamping plate 6 and the connecting block 5 along the height direction. A positioning block 12 is slidably connected inside the lifting groove 11 through clearance fit. A positioning hole 10 is opened in the lower middle part of the moving box 3 to match the positioning block 12. When the positioning block 12 is inserted into the positioning hole 10, the connecting block 5 and the moving box 3 are rigidly fixed, and the clamping plate 6 cannot move, switching to rigid clamping. When the positioning block 12 is disengaged from the positioning hole 10, flexible clamping is restored. Two sets of second lugs 15 are fixedly connected to the lower sides of the mobile box 3 by welding. A connecting frame 17 is fixedly connected to the lower part of the processing table 1 by screws. Motors 18 are fixedly connected to the front and right sides of the connecting frame 17 by flange screws. The power end of the motor 18 penetrates the connecting frame 17 and is fixedly connected to a threaded rod 16 by a key. The other end of the threaded rod 16 is rotatably connected to the inner wall of the connecting frame 17 by a deep groove ball bearing. The two sets of threaded rods 16 are staggered to avoid mutual interference during driving. The threaded rods 16 are threaded to the inside of the corresponding second lugs 15. When the motor 18 is started, the mobile box 3 can be driven to slide along the moving groove 2. The front motor 18 drives the front and rear sets of mobile boxes 3, and the right motor 18 drives the left and right sets of mobile boxes 3, realizing the front and rear and left and right bidirectional centering of the fuel assembly. A connecting groove 13 communicating with the lifting groove 11 is provided on the opposite side of the clamping plate 6. A pulling plate 14 is fixedly connected to the upper part of the positioning block 12 by welding. The pulling plate 14 is slidably connected to the inside of the connecting groove 13 through clearance fit. Pulling the pulling plate 14 can drive the positioning block 12 to move up and down along the lifting groove 11. A locking hole 21 is provided on the inner side of the upper part of the clamping plate 6, and a locking rod 20 that is fitted with the locking hole 21 is slidably connected inside the pull plate 14 through a clearance fit. The pull plate 14 has a control groove 22 inside. The locking rod 20 is fixedly connected to the outside by welding with a fixing ring 23. The fixing ring 23 is slidably connected to the inside of the control groove 22 by clearance fit. The fixing ring 23 and the inner wall of the control groove 22 are fixedly connected by spot welding with a second spring 24. The second spring 24 is sleeved on the outside of the locking rod 20. Under normal conditions, pushing the locking rod 20 into the locking hole 21 locks the position of the pull plate 14 and the positioning block 12, preventing the positioning block 12 from falling. One end of the locking rod 20 penetrates the pull plate 14 and is fixedly connected to a control piece 25 by screws. Pulling the control piece 25 can make the locking rod 20 disengage from the locking hole 21 and unlock the pull plate 14. A rubber pad 19 is glued to one side of the clamp plate 6. The rubber pad 19 prevents the metal clamp plate 6 from directly contacting the zirconium alloy shell of the fuel assembly, preventing scratches, while increasing friction to ensure a stable clamping without slipping.

[0016] Working principle: When using this utility model: the processing table 1 is fixed on the seismic test platform to ensure it is level. The motors 18 on the front and right sides of the connecting frame 17 are started. The initial position is set by the encoder of the motor 18, so that the four sets of moving boxes 3 slide outward along the moving groove 2. The spacing of the clamping plates 6 is greater than the size of the fuel assembly to be tested. The fuel assembly is placed stably in the center of the processing table 1, and the motor 18 is turned off and enabled. The motor 18 is started again. The front motor 18 drives the front and rear sets of moving boxes 3 to slide along the moving groove 2 towards the assembly. The right motor 18 drives the left and right sets of moving boxes 3 to slide synchronously. The first spring 9 pushes the first lug 7 to slide along the guide rod 8, which drives the connecting block 5 and the clamping plate 6 to move towards the assembly until the rubber pad 19 is completely in contact with the assembly shell. The flexible clamping force of the first spring 9 ensures that the assembly is stable and without stress concentration. The seismic testing equipment is started. During the test, the first spring 9 expands and contracts with the vibration, which intensifies the vibration frequency of the fuel assembly and simulates the real low-frequency vibration conditions. The vibration response data of the assembly is collected in real time by the sensor. After the low-frequency test is completed, the seismic testing equipment is stopped. Pulling the control plate 25 on the four sets of clamping plates 6 causes the locking rod 20 to disengage from the locking hole 21, compressing the second spring 24 and pushing the pulling plate 14 downwards, causing the positioning block 12 to slide along the lifting groove 11 until the lower part of the positioning block 12 is inserted into the positioning hole 10 of the moving box 3. Releasing the control plate 25 causes the second spring 24 to return to its original position. At this time, the connecting block 5 is rigidly fixed to the moving box 3, and the clamping plate 6 switches to rigid clamping. Rigid clamping ensures that the components do not shift under high-intensity vibration, avoiding distortion of test data due to loose clamping.

[0017] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0018] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A quick assembly / disassembly and centering fixture for seismic testing of fuel assemblies, comprising a processing table (1), characterized in that: The processing table (1) has four sets of moving slots (2) on its upper part. A moving box (3) is slidably connected inside the moving slot (2). A connecting block (5) is slidably connected inside the moving box (3). A clamping plate (6) is fixedly connected to the upper part of the connecting block (5). A connecting box (4) is fixedly connected to the lower two sides of the moving box (3). A guide rod (8) is fixedly connected inside the connecting box (4). A first ear (7) is slidably connected to the outer side of the guide rod (8). The first ear (7) is fixedly connected to the lower two sides of the connecting block (5). A first spring (9) is fixedly connected between the first ear (7) and the moving box (3). The first spring (9) is sleeved on the outer side of the guide rod (8). A lifting slot (11) is opened in the middle of the clamping plate (6) and the connecting block (5). A positioning block (12) is slidably connected inside the lifting slot (11). A positioning hole (10) that matches the positioning block (12) is opened in the lower middle part of the moving box (3).

2. The quick assembly / disassembly and alignment clamp for seismic testing of fuel assemblies according to claim 1, characterized in that: Two sets of second lugs (15) are fixedly connected to the lower sides of the movable box (3). A connecting frame (17) is fixedly connected to the lower part of the processing table (1). A motor (18) is fixedly connected to the front and right sides of the connecting frame (17). The power end of the motor (18) penetrates the connecting frame (17) and is fixedly connected to a threaded rod (16). The other end of the threaded rod (16) is rotatably connected to the inner wall of the connecting frame (17). The two sets of threaded rods (16) are staggered and the threaded rods (16) are threadedly connected to the inside of the second lugs (15).

3. The quick assembly / disassembly and alignment fixture for seismic testing of fuel assemblies according to claim 1, characterized in that: A connecting groove (13) communicating with the lifting groove (11) is provided on the opposite side between the clamps (6). A pull plate (14) is fixedly connected to the upper part of the positioning block (12), and the pull plate (14) is slidably connected inside the lifting groove (11).

4. The quick assembly / disassembly and alignment fixture for seismic testing of fuel assemblies according to claim 3, characterized in that: The upper inner side of the clamping plate (6) is provided with a locking hole (21), and the inside of the pulling plate (14) is slidably connected with a locking rod (20) that matches the locking hole (21).

5. The quick assembly / disassembly and alignment fixture for seismic testing of fuel assemblies according to claim 4, characterized in that: The pull plate (14) has a control groove (22) inside. A fixing ring (23) is fixedly connected to the outside of the locking rod (20). The fixing ring (23) is slidably connected inside the control groove (22). A second spring (24) is fixedly connected between the fixing ring (23) and the inner wall of the control groove (22). The second spring (24) is sleeved on the outside of the locking rod (20). One end of the locking rod (20) penetrates the pull plate (14) and is fixedly connected to a control piece (25).

6. The quick assembly / disassembly and alignment fixture for seismic testing of fuel assemblies according to claim 1, characterized in that: A rubber pad (19) is fixedly connected between the clamps (6) facing each other on one side.

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