Spent fuel rod conveying device

Abstract

The invention relates to a spent fuel rod conveying device which comprises a conveying platform, a conveying chain, a driving mechanism and a clamping jaw. The conveying platform is used for bearing spent fuel rods; the conveying chain is arranged above the conveying platform; the driving mechanism is in transmission connection with the conveying chain and used for driving the conveying chain to move in the length direction of the conveying platform. The clamping jaw is connected to the conveying chain and used for clamping the spent fuel rod and pushing the spent fuel rod to reach the next station along the conveying platform along with movement of the conveying chain, and full-process automatic conveying of the spent fuel rod from a discharging point to the next station is achieved through the synergistic effect of the conveying platform, the conveying chain and the clamping jaw. According to the spent fuel rod conveying device, the radiation exposure risk caused by direct manual operation is effectively avoided, the technical blank of an automatic carrying device in the field is filled, continuous and directional assembly line type operation is achieved, the problem that in the prior art, the efficiency is low due to dependence on manual operation or frequent transfer is solved, and the working efficiency is improved. And the overall efficiency, reliability and safety of the spent fuel rod post-treatment process are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of spent fuel rod back-end processing technology, and more specifically, to a spent fuel rod conveying device. Background Technology

[0002] Spent fuel rods are nuclear fuel rods that have been removed from the reactor core after undergoing a certain irradiation cycle and are no longer intended for use. Typical characteristics include a cladding made of zirconium alloy or stainless steel, a large amount of radioactive fission products inside, and strong radioactivity and decay heat due to continuous neutron irradiation. Therefore, spent fuel rods must be safely and reliably transported to the next processing station after removal from the reactor. However, in the existing technology, automated handling devices for spent fuel rods are still lacking. Existing operations mostly rely on manual intervention and involve frequent transfers, resulting in low efficiency and poor safety. Summary of the Invention

[0003] Based on this, and to address the aforementioned problems, the present invention provides a spent fuel rod conveying device that automates the handling of spent fuel rods, greatly improving the overall efficiency, reliability, and safety of the spent fuel rod reprocessing process.

[0004] To achieve the above objectives, the present invention provides a spent fuel rod conveying device, including a conveying platform, a conveying chain, a drive mechanism, and grippers; the conveying platform is used to carry spent fuel rods; the conveying chain is disposed above the conveying platform; the drive mechanism is drivenly connected to the conveying chain and is used to drive the conveying chain to move along the length direction of the conveying platform; the grippers are connected to the conveying chain and are used to clamp the spent fuel rods, and push the spent fuel rods along the conveying platform to the next station as the conveying chain moves.

[0005] In one specific embodiment, the gripper includes a connecting portion and a clamping portion. The gripper is connected to the conveyor chain through the connecting portion. The clamping portion is located at the first end of the connecting portion and releases or clamps the spent fuel rods through the opening and closing action of the clamping portion. The clamping portion includes at least two symmetrically arranged clamping arms, and the opposite surfaces of the clamping arms together form a clamping space for the spent fuel rods.

[0006] In one specific embodiment, the opposing surfaces of the clamping arms form a shape that matches the outer contour of the spent fuel rod.

[0007] In one specific embodiment, the end of the conveyor chain facing the gripper is provided with a positioning block, which is used to restrict the displacement of the spent fuel rod at the front end or top of the spent fuel rod after the gripper holds the spent fuel rod.

[0008] In one specific embodiment, the clamping arm includes a connecting end and a free end. The connecting end includes a first connecting piece and a second connecting piece symmetrically arranged in a direction perpendicular to the central axis of the free end. The first end of the first connecting piece and the second connecting piece are connected to the tail of the free end, and the second end extends away from the tail of the free end and forms an opening to accommodate the first end of the connecting portion. The first connecting piece and the second connecting piece are rotatably connected to the first end of the connecting portion, and the inner side of the free end forms a shape that matches the outer wall contour of the spent fuel rod.

[0009] In one specific embodiment, the top of the free end is provided with a protrusion or positioning pin that matches the recessed portion of the spent fuel rod.

[0010] In one specific embodiment, the connecting part includes a housing, and a cylinder is disposed inside the housing. The piston rod of the cylinder is throttlely connected to the connecting end of the clamping arm to drive the clamping arm to perform an opening and closing action.

[0011] In one specific embodiment, the housing is provided with a connector, which is connected to the end of a connecting chain of a winch. The winch is used to simultaneously release the connecting chain when the jaws push the spent fuel rods, and to simultaneously retract the connecting chain after the jaws release the spent fuel rods, so as to assist the jaws in returning to the initial position.

[0012] In one specific embodiment, the conveyor chain is a rigid chain.

[0013] In one specific embodiment, the opposing surfaces of the clamping arms are provided with a plurality of arrayed blind holes, each of which contains a spring and a floating pressure head. One end of the floating pressure head is connected to the spring, and the other end extends out of the blind hole, forming a multi-point adaptive clamping surface for spent fuel rods.

[0014] In one specific embodiment, the opposite surfaces of the clamping arms are provided with flexible damping pads made of radiation-resistant fluororubber or perfluoroether rubber.

[0015] In one specific embodiment, the flexible damping pad is provided with a plurality of arrayed blind holes, each of which is provided with a spring and a floating pressure head. One end of the floating pressure head is connected to the spring, and the other end extends out of the blind hole, forming a multi-point adaptive clamping surface for spent fuel rods.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention provides a spent fuel rod conveying device that, through the coordinated action of a conveying platform, a conveying chain, and grippers, achieves fully automated conveying of spent fuel rods from the unloading point to the next workstation. This effectively avoids the radiation exposure risk caused by direct manual operation and fills the technological gap in automated handling devices in this field. This spent fuel rod conveying device realizes continuous and directional assembly line operation, overcoming the inefficiency caused by reliance on manual labor or frequent transfers in the prior art, and greatly improving the overall efficiency, reliability, and safety of the spent fuel rod reprocessing process. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a spent fuel rod conveying device according to the present invention.

[0018] Figure 2 This is a schematic diagram of the conveyor chain structure in a spent fuel rod conveying device according to the present invention. Figure 1 .

[0019] Figure 3 This is a schematic diagram of the conveyor chain structure in a spent fuel rod conveying device according to the present invention. Figure 2 .

[0020] Figure 4 This is a schematic diagram of the conveyor chain and grippers in a spent fuel rod conveying device according to the present invention. Figure 1 .

[0021] Figure 5 This is a schematic diagram of the conveyor chain and grippers in a spent fuel rod conveying device according to the present invention. Figure 2 .

[0022] Figure 6 This is a schematic diagram of the structure of the spring and floating pressure head installed on the clamping arm in a spent fuel rod conveying device according to the present invention. Figure 1 .

[0023] Figure 7 This is a schematic diagram of the structure of the spring and floating pressure head installed on the clamping arm in a spent fuel rod conveying device according to the present invention. Figure 2 . Detailed Implementation

[0024] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0026] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0028] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figures 1-5As shown, this embodiment provides a spent fuel rod conveying device, which is connected to the outside of a nuclear reactor for automatically conveying spent fuel rods 100 to the next work station. Understandably, the next work station is typically a spent fuel rod 100 dismantling station, a cooling station, or a temporary storage station. The spent fuel rod conveying device includes a conveying platform 10, a conveyor chain 20, a drive mechanism (not shown in the figure), and grippers 30. The conveying platform 10 carries the spent fuel rods 100. The conveyor chain 20 is positioned above the conveying platform 10. The drive mechanism is connected to the conveyor chain 20 and drives the conveyor chain 20 to move along the length of the conveying platform 10. The grippers 30 are connected to the conveyor chain 20 and grip the spent fuel rods 100, pushing them along the conveying platform 10 to the next work station as the conveyor chain 20 moves. In this embodiment, the drive mechanism is activated, transmitting power to the conveyor chain 20. The drive mechanism can be a servo motor or a stepper motor, which drives the spent fuel rod 100 to move linearly. The gripper 30 is connected to the conveyor chain 20. Therefore, the movement of the conveyor chain 20 is directly converted into the linear movement of the gripper 30. Understandably, before the gripper 30 moves, it holds the spent fuel rod 100 at the starting point of the conveyor platform 10 and then pushes the spent fuel rod 100 along the conveyor platform 10 to the next station. The spent fuel rod conveying device provided in this embodiment realizes the fully automated conveying of the spent fuel rod 100 from the unloading point to the next station through the coordinated action of the conveyor platform 10, the conveyor chain 20 and the gripper 30. It effectively avoids the radiation exposure risk caused by direct manual operation and fills the technical gap of automated handling devices in this field. The spent fuel rod conveying device realizes continuous and directional assembly line operation, overcomes the inefficiency caused by reliance on manual labor or frequent transfer in the prior art, and greatly improves the overall efficiency, reliability and safety of the spent fuel rod 100 post-processing process.

[0030] For example, the gripper 30 can be fixedly connected or slidably connected to the conveyor chain 20. When the gripper 30 is fixedly connected to the conveyor chain 20, it moves synchronously with the conveyor chain 20. When the gripper 30 is slidably connected to the conveyor chain 20, the gripper 30 can also slide on the conveyor chain to perform secondary movements while moving with the conveyor chain 20.

[0031] like Figures 4-5As shown, in one specific embodiment, the gripper 30 includes a connecting part 301 and a clamping part 302. The gripper 30 is connected to the conveyor chain 20 through the connecting part 301. The clamping part 302 is located at the first end of the connecting part 301 and releases or clamps the spent fuel rod 100 through the opening and closing action of the clamping part 302. The clamping part 302 includes at least two symmetrically arranged clamping arms 3021. The opposite surfaces of the clamping arms 3021 together form the clamping space of the spent fuel rod 100. Through the synchronous opposite or reciprocating movement of the two symmetrical clamping arms 3021, the spent fuel rod 100 can be stably clamped, ensuring that the line of action of the clamping force passes through the center of the fuel rod, thereby avoiding the fuel rod from rolling or shifting during the conveying process due to eccentric force.

[0032] In one specific embodiment, the opposing surfaces of the clamping arms 3021 form a shape that matches the outer contour of the spent fuel rod 100. Understandably, the opposing surfaces can be arc-shaped concave surfaces used to fit the outer peripheral wall of the cylindrical spent fuel rod. The arc-shaped concave surface forms a conformal contact with the outer wall of the cylindrical spent fuel rod, transforming the clamping force from limited point or line contact to a large-area curved surface contact. This avoids local stress concentration and perfectly addresses the technical problem that the spent fuel rod 100 is easily crushed or scratched due to "irradiation embrittlement," ensuring reliable and stable clamping under various working conditions.

[0033] In one specific embodiment, the end of the conveyor chain 20 facing the gripper 30 is provided with a positioning block 201, which is used to restrict the displacement of the spent fuel rod 100 at the front end or top of the spent fuel rod 100 after the gripper 30 clamps the spent fuel rod 100.

[0034] like Figures 4-5As shown, in one specific embodiment, the clamping arm 3021 includes a connecting end 322 and a free end 323. The connecting end 322 includes a first connecting piece 3221 and a second connecting piece 3222 symmetrically arranged in a direction perpendicular to the central axis of the free end 323. The first ends of the first connecting piece 3221 and the second connecting piece 3222 are connected to the tail of the free end 323, and the second ends extend away from the tail of the free end 323 and form an opening to accommodate the first end of the connecting portion 301. The first connecting piece 3221 and the second connecting piece 3222 are rotatably connected to the first end of the connecting portion 301. The inner side of the free end 323 forms a shape that matches the outer wall contour of the spent fuel rod 100. The first connecting piece 3221 and the second connecting piece 3222 are essentially two symmetrical levers. Their rotational connection point with the connecting part 301 forms a fulcrum. When the driving force is applied to the appropriate position of the first connecting piece 3221 and the second connecting piece 3222, the lever will rotate around the fulcrum, amplify the input motion and force and transmit it to the free end 323, thereby realizing the precise and stable opening and closing motion of the free end 323 and completing the release and clamping action of the spent fuel rod 100.

[0035] like Figure 5 As shown, in one specific embodiment, the top of the free end 323 is provided with a protrusion or positioning pin 3022 that matches the recessed part of the spent fuel rod 100. The top of the free end 323 refers to the position of the free end 323 furthest from the connecting end 322, and the tail of the free end 323 refers to the position opposite to the top, which greatly enhances the stability and accuracy of the spent fuel rod 100 clamping.

[0036] In one specific embodiment, the connecting part 301 includes a housing, and a cylinder (not shown in the figure) is disposed inside the housing. The piston rod of the cylinder is operatively connected to the connecting end 322 of the clamping arm 3021 to drive the clamping arm 3021 to perform opening and closing actions. Specifically, the opposing surfaces of the first connecting piece 3221 and the second connecting piece 3222 are provided with a connecting rod (not shown in the figure) connected to the piston rod of the cylinder. After the cylinder is started, the piston rod pushes the first connecting piece 3221 and the second connecting piece 3222 through the driving connecting rod, thereby causing the clamping arm 3021 to open and close.

[0037] like Figure 1As shown, in one specific embodiment, the housing is provided with a connector, which is connected to the end of a connecting chain 401 of a winch 40. The winch 40 is used to simultaneously release the connecting chain 401 when the gripper 30 pushes the spent fuel rod 100, and to simultaneously retract the connecting chain 401 and drive the gripper 30 to reset after the gripper 30 releases the spent fuel rod 100. The gripper 30 resetting means that the gripper 30 returns to the starting position of the conveying platform 10, that is, the position at the beginning of the next work cycle. This position usually corresponds to the loading point of the spent fuel rod 100. This embodiment provides a spent fuel rod conveying device that utilizes a winch 40 as an active take-up and take-down mechanism. Its core function is not simple traction, but rather to ensure that the connecting chain 401 maintains a moderate tension throughout the entire working stroke of the gripper 30 by precisely synchronizing with the movement of the conveying chain 20. This avoids the connecting chain 401 from tangling, jamming, or dragging on the ground due to slack. At the same time, it provides an active reset assist force when the gripper 30 returns unloaded, ensuring that the gripper 30 returns to the starting position quickly and accurately.

[0038] In one specific embodiment, the conveyor chain 20 is a rigid chain. Rigid chains have extremely high stiffness and stability when subjected to axial pressure, and almost no compression or bending deformation occurs. This ensures that when the gripper 30 pushes the spent fuel rod 100, the driving force can be transmitted efficiently and without loss, effectively avoiding thrust loss and deviation of the fuel rod conveying path caused by the deflection of the conveyor chain 20, and realizing precise linear propulsion.

[0039] like Figures 6-7 As shown, in one specific embodiment, the opposing surfaces of the clamping arm 3021 are provided with a plurality of arrayed blind holes. Each blind hole is provided with a spring 331 and a floating pressure head 332. One end of the floating pressure head 332 is connected to the spring 331, and the other end extends out of the blind hole by a preset length, forming more than 100 adaptive clamping surfaces for spent fuel rods. Understandably, the cladding material (such as zirconium alloy) of spent fuel rods 100 will become irradiated and embrittled after long-term neutron irradiation, and its toughness and ductility will decrease significantly. This means that spent fuel rods 100 are very fragile. During mechanical handling, any improper clamping, collision or scratching may cause the cladding to break and cause radioactive material leakage. The spent fuel rod conveying device provided in this embodiment can independently adapt to the micro-unevenness or macro-minor curvature of the fuel rod surface under the action of the spring 331 behind it. When the clamping arm 3021 applies clamping force, it can automatically adjust the load on each clamping head to ensure that the contact stress is highly uniformly distributed macroscopically. This eliminates the possibility of local stress exceeding the bearing limit of the cladding material from the root, prevents cladding breakage during handling, and greatly reduces the risk of radioactive material leakage.

[0040] In one specific embodiment, the opposing surfaces of the clamping arms 3021 are provided with flexible damping pads made of radiation-resistant fluororubber or perfluoroether rubber (not shown in the figure). The flexible damping pads are arranged in an array at intervals on the inner side of the free end 323 of the clamping arms 3021. The viscoelasticity of the flexible damping pads can effectively absorb the impact energy of the clamping arms 3021 when clamping the spent fuel rods 100 and the small vibrations during the transportation process, preventing these dynamic loads from acting on the brittle cladding and fundamentally eliminating the risk of cladding damage caused by mechanical handling.

[0041] In one specific embodiment, the flexible damping pad is provided with a plurality of arrayed blind holes. Each blind hole is provided with a spring 331 and a floating pressure head 332. One end of the floating pressure head 332 is connected to the spring 331, and the other end extends out of the blind hole by a preset length, forming more than 100 adaptive clamping surfaces for the spent fuel rod. Under the action of the spring 331 behind it, each floating pressure head 332 can independently adapt to the microscopic unevenness or macroscopic slight bending of the fuel rod surface. When the clamping arm 3021 applies clamping force, it can automatically adjust the load on each pressure head to ensure that the contact stress is highly uniformly distributed macroscopically. This eliminates the possibility of local stress exceeding the bearing limit of the cladding material from the root, prevents cladding damage during transportation, and greatly reduces the risk of radioactive material leakage.

[0042] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the foregoing description. Therefore, all changes falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0043] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A spent fuel rod conveying device, characterized in that: It includes a conveying platform, a conveyor chain, a drive mechanism, and grippers; the conveying platform is used to carry spent fuel rods; the conveyor chain is positioned above the conveying platform; The drive mechanism is connected to the conveyor chain and is used to drive the conveyor chain to move along the length of the conveyor platform; the gripper is connected to the conveyor chain and is used to grip the spent fuel rod and push the spent fuel rod along the conveyor platform to the next station as the conveyor chain moves.

2. The spent fuel rod conveying device according to claim 1, characterized in that: The gripper includes a connecting part and a clamping part. The gripper is connected to the conveyor chain through the connecting part. The clamping part is located at the first end of the connecting part and releases or clamps the spent fuel rods through the opening and closing action of the clamping part. The clamping part includes at least two symmetrically arranged clamping arms, and the opposing surfaces of the two clamping arms together form the clamping space for the spent fuel rods.

3. A spent fuel rod conveying device according to claim 2, characterized in that: The opposing surfaces of the clamping arms form a shape that matches the outer contour of the spent fuel rod.

4. A spent fuel rod conveying device according to claim 2, characterized in that: The conveyor chain has a positioning block at one end facing the gripper, which is used to restrict the displacement of the spent fuel rod at the front end or top of the spent fuel rod after the gripper holds it.

5. A spent fuel rod conveying device according to claim 2, characterized in that: The clamping arm includes a connecting end and a free end. The connecting end includes a first connecting piece and a second connecting piece symmetrically arranged in a direction perpendicular to the central axis of the free end. The first end of the first connecting piece and the second connecting piece are connected to the tail of the free end, and the second end extends away from the tail of the free end and forms an opening to accommodate the first end of the connecting part. The first connecting piece and the second connecting piece are rotatably connected to the first end of the connecting part. The inner side of the free end forms a shape that matches the outer wall contour of the spent fuel rod.

6. A spent fuel rod conveying device according to claim 5, characterized in that: The top of the free end is provided with a protrusion or positioning pin that matches the recessed part of the spent fuel rod.

7. A spent fuel rod conveying device according to claim 5, characterized in that: The connecting part includes a housing, and a cylinder is disposed inside the housing. The piston rod of the cylinder is throttlely connected to the connecting end of the clamping arm to drive the clamping arm to perform an opening and closing action.

8. A spent fuel rod conveying device according to claim 7, characterized in that: The housing is provided with a connector, which is connected to the end of a connecting chain of a winch. The winch is used to simultaneously release the connecting chain when the jaws push the spent fuel rods, and to simultaneously retract the connecting chain after the jaws release the spent fuel rods, so as to assist the jaws in returning to the initial position.

9. A spent fuel rod conveying device according to claim 1, characterized in that: The conveyor chain is a rigid chain.

10. A spent fuel rod conveying device according to any one of claims 2-5, characterized in that: The opposing surfaces of the clamping arms are provided with a plurality of arrayed blind holes. Each blind hole contains a spring and a floating pressure head. One end of the floating pressure head is connected to the spring, and the other end extends out of the blind hole, forming a multi-point adaptive clamping surface for spent fuel rods.

11. A spent fuel rod conveying device according to any one of claims 2-5, characterized in that: The opposing surfaces of the clamping arms are provided with flexible damping pads made of radiation-resistant fluororubber or perfluoroether rubber.

12. A spent fuel rod conveying device according to claim 11, characterized in that: The flexible damping pad is provided with a number of arrayed blind holes. Each blind hole is provided with a spring and a floating pressure head. One end of the floating pressure head is connected to the spring, and the other end extends out of the blind hole to form a multi-point adaptive clamping surface for spent fuel rods.

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