Fuel assembly appearance on-line inspection device

Abstract

The utility model relates to the technical field of fuel assembly inspection, and provides a fuel assembly appearance on-line inspection device, which comprises an underwater component, a video detection device and a control device, the supporting component comprises a supporting bracket, and an adjuster and a fixer which are arranged on the supporting bracket, the supporting bracket is arranged at the top of the pool, and the fixer is used for realizing fixation with the pool; a large hanger; the upper ends of the first tensioning pieces are connected with the large lifting appliance, and the lower ends are connected with the supporting bracket; a small hanger; the upper ends of the second tensioning pieces are connected with the small lifting appliance, the lower ends of the second tensioning pieces are connected with the underwater support, and the second tensioning pieces and the supporting support are fixed or loosened through adjusters. According to the utility model, the integrity and the surface state of the fuel assembly can be checked on line in real time in the unloading process, and the overhaul time is not occupied; the fuel assembly does not need to be moved for many times, the irradiation dose of inspectors is reduced, and the safety and irradiation risks of the inspectors and fuel assembly inspection are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel assembly inspection, in particular to an online fuel assembly appearance inspection device. Background Art

[0002] The most technologically mature nuclear island design internationally utilizes a pressurized water reactor (PWR). The PWR core consists of fuel assemblies, control rod assemblies, and other related components. The fuel assembly is the most crucial component in the core, consisting of fuel rods, lower and upper tube holders, control rod guide tubes, and spacer grids. First, fuel assemblies operate in a high-temperature, high-pressure, and highly irradiated environment. Due to factors such as assembly stress and thermal stress, localized deformation of the fuel rods and the overall shape of the fuel assembly can occur. In severe cases, this can affect the proper insertion of control rods and jeopardize the safe operation of the reactor. Second, during reactor outages for overhaul, the surfaces of fuel assemblies are susceptible to bumps, scratches, bending, or deformation during fuel assembly refueling, unloading, and reinstallation. The grids are particularly susceptible to damage during transport. Therefore, irradiated fuel assemblies undergo a visual inspection before reuse.

[0003] Nuclear power plants typically lack dedicated underwater radiation-resistant camera systems for visual inspection of fuel assemblies. Typically, after all fuel assemblies are unloaded from the core, portable underwater radiation-resistant cameras are used to spot-check fuel assemblies in the spent fuel pool. This fails to confirm the integrity of all fuel assemblies. However, this offline inspection consumes time during overhauls, impacting reactor turnaround times. Furthermore, the repeated movement of fuel assemblies during inspections can cause new collisions or scratches, increasing safety and radiation risks for personnel and fuel assemblies. Therefore, the development of an online inspection device that can address these issues is urgently needed. Utility Model Content

[0004] The purpose of the utility model is to provide an on-line inspection device for the appearance of a fuel assembly to solve the above-mentioned defects of the prior art.

[0005] The utility model is achieved through the following technical solutions:

[0006] A fuel assembly appearance online inspection device, comprising:

[0007] An underwater component, comprising an underwater bracket and a video detection device disposed on the underwater bracket;

[0008] The support component includes a support bracket, an adjuster and a fixer provided on the support bracket, the support bracket is placed on the top of the pool, and the fixer is used to achieve fixation with the pool;

[0009] Large spreader;

[0010] A plurality of first tensioning members, the upper ends of which are connected to the large spreader and the lower ends of which are connected to the supporting bracket;

[0011] small spreaders; and

[0012] A plurality of second tensioning members have upper ends connected to the small slings and lower ends connected to the underwater brackets, and the second tensioning members are fixed or loosened with the supporting brackets through regulators.

[0013] Optionally, the underwater component further includes a lighting device provided on an underwater bracket.

[0014] Optionally, two of the video detection devices and two of the lighting devices are provided, the two video detection devices are respectively provided at the two ends of one diagonal of the underwater bracket, and the two lighting devices are respectively provided at the two ends of the other diagonal of the underwater bracket.

[0015] Optionally, the adjuster includes a lock and an adjustment seat, the adjustment seat is fixedly connected to the support bracket, the lock is placed on the top of the adjustment seat, the second tensioning member passes through the adjustment seat and the lock, the lock is provided with a locking hole for limiting the up and down movement of the second tensioning member, and an unlocking hole for allowing the second tensioning member to move up and down, and the unlocking hole is connected to the locking hole.

[0016] Optionally, the adjustment seat includes a nut plate and an adjustment screw with a hollow interior. The nut plate is fixedly connected to the support bracket, and the adjustment screw is connected to the nut plate through threads.

[0017] Optionally, the adjuster further includes a limiting member, which is movably connected between two sides of the locking hole close to one end of the unlocking hole, and is used to limit the second tensioning member from sliding from the locking hole into the unlocking hole or to release the restriction.

[0018] Optionally, the limiting member includes a U-shaped lock and a block, the lock is provided with through holes for accommodating both ends of the U-shaped lock, the block is fixedly connected to one end of the U-shaped lock to limit the end of the U-shaped lock from exiting the through hole, and one end of the U-shaped lock can exit the through hole.

[0019] Optionally, four fixers are provided, each including a connecting arm and a locking screw. The connecting arm is connected to the lower end of the support bracket, the locking screw is threadedly connected to the connecting arm, and the end of the locking screw is used to press against the wall of the pool.

[0020] Optionally, the fixer further comprises a guide rail extending along the axis direction of the locking screw, the connecting arm is connected to a sliding sleeve, the sliding sleeve is slidably connected to the guide rail, and the sliding sleeve is connected to a screw for tightening the guide rail.

[0021] Optionally, the support component further includes four balancers, which are arranged at the four corners of the support bracket. The balancer includes a leveling block and a connecting screw. The leveling block is arranged at the bottom of the connecting screw, and the connecting screw is connected to the support bracket through a threaded connection.

[0022] The technical solution of this utility model has at least the following advantages and beneficial effects: in the utility model, the supporting component is hoisted by the large hoist and the first tension piece, and the underwater component is hoisted by the small hoist and the second tension piece. After hoisting into place, the supporting component is fixed on the top of the pool, and the second tension piece is locked by the regulator to fix it to the supporting bracket. After the large hoist is removed, the weight of the underwater component is borne by the supporting component through the second tension piece. The underwater component is equipped with video detection equipment, which can check the integrity and surface condition of the fuel assembly online in real time during the unloading process, without taking up overhaul time; there is no need to move the fuel assembly multiple times, and the radiation dose of the inspectors is reduced, thereby reducing the safety and radiation risks of the personnel and fuel assembly inspections. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is a schematic structural diagram of an online fuel assembly appearance inspection device provided by the present invention;

[0025] Figure 2 A schematic diagram of the arrangement of the video detection equipment relative to the raw material assembly;

[0026] Figure 3 It is the structural diagram of the regulator;

[0027] Figure 4 for Figure 1 A magnified view of point A;

[0028] Icons: 1- underwater parts, 101- underwater bracket, 102- video detection equipment, 103- lighting equipment, 2- supporting parts, 201- adjuster, 2011- lock, 20111- locking hole, 20112- unlocking hole, 2012- adjusting seat, 20121- nut plate, 20122- adjusting screw, 2013- limiter, 20131- U-shaped lock, 20132- stopper, 202- fastener, 2021- connecting arm, 2022- locking screw, 2023- sliding sleeve, 2024- guide rail, 203- balancer, 2031- leveling block, 2032- connecting screw, 204- supporting bracket, 3- large sling, 4- small sling, 5- second tensioning member, 6- fuel assembly. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0032] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0033] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0034] refer to Figure 1 , an online appearance inspection device for a fuel assembly 6 includes an underwater component 1, a supporting component 2, a large sling 3, a small sling 4, a plurality of first tensioning members (not shown) and a plurality of second tensioning members 5.

[0035] The underwater component 1 includes an underwater bracket 101 and a video detection device 102 mounted on the bracket 101. In this embodiment, the underwater component 1 also includes a lighting device 103 mounted on the bracket 101. The video detection device 102 is a radiation-resistant camera, and the lighting device 103 is an LED light for supplemental lighting. In practice, the camera can be mounted on the underwater bracket 101 using a horizontally rotatable pan / tilt head to facilitate adjustment of its camera angle. After each device is installed, a counterweight is applied to ensure that the underwater component 1 remains level when hoisted.

[0036] Furthermore, in this embodiment, two video detection devices 102 and two lighting devices 103 are provided. The two video detection devices 102 are respectively provided at the two ends of one diagonal line of the underwater bracket 101 (on this basis, it is easy to understand that the underwater bracket 101 is a rectangular frame structure, and the internal length and width should not affect the movement of the fuel assembly 6), and the two lighting devices 103 are respectively provided at the two ends of the other diagonal line of the underwater bracket 101. Figure 2 As shown, two video inspection devices 102 are located on a diagonal line of the fuel assembly 6. One video inspection device 102 inspects two surfaces of the fuel assembly 6. The two video inspection devices 102 just cover the four surfaces of the fuel assembly 6. During inspection, the fuel assembly 6 is lifted upward from between the two video inspection devices 102, thereby achieving appearance inspection of the entire fuel assembly 6.

[0037] Reference again Figure 1The support component 2 includes a support bracket 204, an adjuster 201, and a retainer 202 mounted on the support bracket 204. The specific shape of the support bracket 204 is not limited. In practical applications, the support bracket 204 should not interfere with the fuel basket's trajectory or the support bracket 204's own movement, depending on the characteristics and movement path of the fuel assembly 6, the fuel basket's trajectory, and the on-site environment of the transfer channel. Taking the application of the online inspection device to an AP1000 fuel assembly 6 as an example (where one side of the transfer channel is obstructed and the fuel basket is offset relative to the vertical center of the spent pool water gate), the support bracket 204 in this embodiment is generally in the shape of a U-shaped structure with one end open.

[0038] The support component 2 of this embodiment further includes four balancers 203, which are arranged at the four corners of the support bracket 204. Figure 4 The balancer 203 includes a leveling block 2031 and a connecting screw 2032. The leveling block 2031 is arranged at the bottom of the connecting screw 2032. The connecting screw 2032 is connected to the support bracket 204 through a threaded connection. By adjusting the height of each leveling block 2031, the horizontality of the support bracket 204 can be adjusted, thereby adjusting the horizontality of the camera underwater.

[0039] The fixing device 202 fixes the supporting bracket 204 to the pool (not shown) after the supporting bracket 204 is hoisted into place. As an option, the fixing device 202 is provided with four fixing devices. Figure 4 The fixture 202 includes a connecting arm 2021 and a locking screw 2022. The connecting arm 2021 is connected to the lower end of the support bracket 204. The locking screw 2022 is threadedly connected to the connecting arm 2021. After the support bracket 204 is leveled, the four locking screws 2022 are screwed to make them abut against the pool wall, thereby limiting the position of the support bracket 204. Furthermore, the fixture 202 also includes a guide rail 2024 extending along the axis of the locking screw 2022. The connecting arm 2021 is connected to a sliding sleeve 2023, which is slidably connected to the guide rail 2024. The sliding sleeve 2023 is connected to a screw (not shown) for abutting the guide rail 2024. This arrangement facilitates adjustment of the position of the locking screw 2022 and prevents the locking screw 2022 from being too long or too short. It is easy to understand that in other embodiments of this embodiment, the fixer 202 can of course also adopt other forms, such as a suction cup, which is used to adhere to the red wall to fix the support bracket 204.

[0040] The upper end of the first tensioning member is connected to the large sling 3, and the lower end of the first tensioning member is connected to the support bracket 204; the upper end of the second tensioning member 5 is connected to the small sling 4, and the lower end of the second tensioning member 5 is connected to the underwater support 101. In actual application, the top of the support bracket 204 and the top of the underwater support 101 are provided with lifting rings. Similarly, the bottoms of the large sling 3 and the small sling 4 are also provided with corresponding lifting rings. In addition, the tops of the large sling 3 and the small sling 4 are also provided with lifting rings for connecting to the lifting part of the lifting equipment through the tensioning member. In this embodiment, the lifting equipment can directly adopt the overhead crane used to grab and transfer the fuel assembly 6. As an option, in this embodiment, the first tensioning member is a wire rope, and the second tensioning member 5 is a lifting chain. Of course, in other embodiments, the first tensioning member and the second tensioning member can be selected from wire ropes, lifting chains, or a combination of the two as needed.

[0041] The regulator 201 is used to fix or loosen the second tensioning member 5 and the support bracket 204. When the second tensioning member 5 is fixed to the support bracket, it is equivalent to the support bracket 204 bearing the weight of the underwater component 1. When the second tensioning member 5 is loosened from the support bracket, it is equivalent to the small sling 4 bearing the weight of the underwater component 1.

[0042] refer to Figure 3 In this embodiment, the adjuster 201 includes a latch 2011 and an adjustment seat 2012. The adjustment seat 2012 is fixedly connected to the support bracket 204. The latch 2011 is placed on the top of the adjustment seat 2012. The second tensioning member 5 passes through the adjustment seat 2012 and the latch 2011. The latch 2011 is provided with a locking hole 20111 for limiting the vertical movement of the second tensioning member 5, and an unlocking hole 20112 for allowing the second tensioning member 5 to move up and down. The unlocking hole 20112 is connected to the locking hole 20111. As an option, the locking hole 20111 is a bar-shaped through hole to limit the downward movement of the lifting chain. The unlocking hole 20112 is circular. After the lifting chain slides from the locking hole 20111 into the unlocking hole 20112, the lifting chain can move freely relative to the support bracket 204. Of course, in other embodiments, the locking hole 20111 and the unlocking hole 20112 can be of other shapes as long as they meet the above functions. Furthermore, the adjustment seat 2012 of this embodiment includes a nut plate 20121 and an adjustment screw 20122 having a hollow interior. The nut plate 20121 is fixedly connected to the support bracket 204, and the adjustment screw 20122 is threadedly connected to the nut plate 20121. This arrangement facilitates fine-tuning the height of the underwater component 1 by turning the adjustment screw 20122 when the weight of the underwater component 1 is supported by the support bracket 204. It will be readily understood that in other embodiments, the adjuster 201 may also employ other structures to achieve the same function, such as employing a pair of claws that can move toward or away from each other, which, when closed, restrict the downward movement of the lifting chain.

[0043] On this basis, the regulator 201 further includes a limiting member 2013, which is movably connected between the two sides of the locking hole 20111 near the unlocking hole 20112, and is used to limit the second tensioning member 5 from sliding from the locking hole 20111 into the unlocking hole 20112 or to release the restriction. In this embodiment, the limiting member 2013 includes a U-shaped lock buckle 20131 and a stopper 20132. The lock 2011 is provided with through holes at both ends of the U-shaped lock buckle 20131, and the stopper 20132 is fixedly connected ( For example, it is welded) to one end of the U-shaped lock buckle 20131 to limit the end of the U-shaped lock buckle 20131 from exiting the through hole, and one end of the U-shaped lock buckle 20131 can exit the through hole, that is, when both ends of the U-shaped lock buckle 20131 are inserted into the corresponding through holes at the same time, the second tensioning member 5 is limited to slide from the locking hole 20111 into the unlocking hole 20112. When one end of the U-shaped lock buckle 20131 exits the corresponding through hole and rotates a certain angle, the second tensioning member 5 can slide from the locking hole 20111 into the unlocking hole 20112. It is easy to understand that in other embodiments, the limit member 2013 can of course also adopt other structures to achieve the same function. For example, the limiter is a screw connected to the lock 2011 and passing through the side wall of the locking hole. When the screw exits the locking hole 20111, the second tensioning member 5 can slide from the locking hole 20111 into the unlocking hole 20112. The screw blocks the locking hole 20111, thereby limiting the second tensioning member 5 from sliding from the locking hole 20111 into the unlocking hole 20112.

[0044] On the basis of the above, the following steps are adopted when installing the online inspection device:

[0045] S1. Assemble the underwater component 1 and the support component 2 separately. Assembling the underwater component 1 means installing the video detection device 102 and the lighting device 103 on the underwater bracket 101, adjusting the video detection angle, lighting angle and brightness, and performing counterweighting. Assembling the support component 2 means connecting the fixer 202, the regulator 201, and the balancer 203 to the support bracket 204.

[0046] S2. Connect the large sling 3 and the support component 2 through the first tensioning member, and connect the large sling 3 through the lifting equipment, lift the support component 2 to the top of the underwater component 1, and then connect the underwater component 1 and the support component 2 through the second tensioning member 5, so that the weight of the underwater component 1 is borne by the support component 2; it is easy to understand that at this time, the middle part of the second tensioning member 5 is fixed to the support bracket 204 through the fixer 202, and the second tensioning member 5 should be reserved above the fixer 202 for subsequent lowering. In actual application, a support plate can also be set on the support bracket 204 to place the reserved part of the second tensioning member 5;

[0047] S3. Lift the support component 2 to the top of the pool using the large lifting device 3, level it using the balancer 203, and then secure the support component 2 using the fixture 202.

[0048] S4. Connect the lifting device to the small sling 4. The small sling 4 lifts the second tension member 5 until it is in a taut state. Release the adjuster 201 (this allows the second tension member 5 to move up and down relative to the support member 2. At this time, the weight of the underwater component 1 is borne by the small sling 4). Then, lower the underwater component 1 until the underwater support 101 is slightly higher than the fuel basket containing the fuel assembly 6.

[0049] S4. Turn on the video inspection device 102 and the lighting device 103. Use the video inspection device to observe whether the position of the fuel basket is in the appropriate position within its line of sight. If not, use the adjustment screw 20122 of the regulator 201 to fine-tune the height of the underwater bracket 101 and use the balancer 203 to adjust the horizontality of the underwater bracket 101. After completion, use the regulator 201 to lock the tensioning member (i.e., the weight of the underwater component 1 is once again borne by the support component 2), and remove the large sling 3 and the small sling 4 to complete the installation.

[0050] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A fuel assembly appearance online inspection device, characterized in that: include: An underwater component, comprising an underwater bracket and a video detection device disposed on the underwater bracket; The support component includes a support bracket, an adjuster and a fixer provided on the support bracket, the support bracket is placed on the top of the pool, and the fixer is used to achieve fixation with the pool; Large spreader; A plurality of first tensioning members, the upper ends of which are connected to the large spreader and the lower ends of which are connected to the supporting bracket; small spreaders; and A plurality of second tensioning members have upper ends connected to the small slings and lower ends connected to the underwater brackets, and the second tensioning members are fixed or loosened with the supporting brackets through regulators.

2. The fuel assembly appearance online inspection device according to claim 1, characterized in that: The underwater component also includes a lighting device arranged on the underwater bracket.

3. The fuel assembly appearance online inspection device according to claim 2, characterized in that: There are two video detection devices and two lighting devices, respectively. The two video detection devices are respectively arranged at the two ends of one diagonal of the underwater bracket, and the two lighting devices are respectively arranged at the two ends of the other diagonal of the underwater bracket.

4. The fuel assembly appearance online inspection device according to claim 1, characterized in that: The adjuster includes a lock and an adjustment seat. The adjustment seat is fixedly connected to the support bracket. The lock is placed on the top of the adjustment seat. The second tensioning member passes through the adjustment seat and the lock. The lock is provided with a locking hole for limiting the up and down movement of the second tensioning member, and an unlocking hole for allowing the second tensioning member to move up and down. The unlocking hole is connected to the locking hole.

5. The fuel assembly appearance online inspection device according to claim 4, characterized in that: The adjustment seat includes a nut plate and an adjustment screw with a hollow interior. The nut plate is fixedly connected to the support bracket, and the adjustment screw is connected to the nut plate through threads.

6. The fuel assembly appearance online inspection device according to claim 4, characterized in that: The adjuster further includes a limiting member, which is movably connected between two sides of the locking hole close to one end of the unlocking hole, and is used to limit the second tensioning member from sliding from the locking hole into the unlocking hole or to release the restriction.

7. The fuel assembly appearance online inspection device according to claim 6, characterized in that: The limiting part includes a U-shaped lock and a block. The lock is provided with through holes for accommodating both ends of the U-shaped lock. The block is fixedly connected to one end of the U-shaped lock to limit the end of the U-shaped lock from exiting the through hole, and one end of the U-shaped lock can exit the through hole.

8. The fuel assembly appearance online inspection device according to claim 1, characterized in that: There are four fixers, each of which includes a connecting arm and a locking screw. The connecting arm is connected to the lower end of the support bracket, the locking screw is connected to the connecting arm through a threaded connection, and the end of the locking screw is used to press against the wall of the pool.

9. The fuel assembly appearance online inspection device according to claim 8, characterized in that: The fixer also includes a guide rail extending along the axis direction of the locking screw. The connecting arm is connected to a sliding sleeve, which is slidably connected to the guide rail. The sliding sleeve is connected to a screw for tightening the guide rail.

10. The fuel assembly appearance online inspection device according to claim 1, characterized in that: The support component also includes four balancers, which are arranged at the four corners of the support bracket. The balancer includes a leveling block and a connecting screw. The leveling block is arranged at the bottom of the connecting screw, and the connecting screw is connected to the support bracket through a threaded connection.

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