Device and method for separating fuel pellet from cladding tube

Abstract

The embodiment of the invention relates to the technical field of disassembly of fuel elements through a mechanical method, in particular to a device and method for separating a fuel pellet from a cladding pipe. The separation device comprises a separation main body, a cladding tube holder, an ejection piece and a pellet collection assembly. The separation body forms a separation space. The cladding tube holder is used for holding the cladding tube, and the cladding tube holder is removably arranged in the separation space. And the ejection piece is arranged on the separation main body and is used for upwards ejecting the fuel pellets in the cladding tube out of the cladding tube. The pellet collecting assembly is arranged to form a collecting groove used for collecting the fuel pellets ejected out of the cladding tube, and the pellet collecting assembly is removably arranged on the side, away from the ejection piece, of the cladding tube holding piece. According to the separation device disclosed by the embodiment of the invention, the fuel pellets are upwards ejected out of the cladding tube and are collected by the pellet collection assembly, so that the integrity of the fuel pellets is improved.

Description

Technical Field

[0001] Embodiments of the present application relate to the technical field of disassembling fuel elements using mechanical methods, and in particular, to a device and method for separating a fuel pellet from a cladding tube. Background Art

[0002] This section of content merely provides background information related to the present application and does not necessarily constitute prior art.

[0003] The study of the fission product distribution and release behavior of the fuel pellets of the reactor's fuel elements is very important for studying the performance of the fuel pellets. The study of the fission product distribution and release behavior mainly relies on analyzing the microstructural changes of the fuel pellets along the radial direction, conducting quantitative analysis of the fission products, and implementing an off-pile annealing test. The annealing test needs to be carried out under high temperature conditions. In some cases, the annealing test temperature may reach the melting temperature of the fuel pellets. Since the melting temperature of the fuel pellets is higher than the melting temperature of the cladding tube, the cladding tube melts and interferes with the release of fission products and microstructure research of the fuel pellets. Therefore, before conducting the annealing test, the cladding tube needs to be separated from the fuel pellets. At present, there are still many problems in the process of separating the cladding tube from the fuel pellets, which affects the accuracy of the fuel pellet analysis test results. Summary of the invention

[0004] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0005] In order to solve the above technical problems, embodiments of the present application provide a device and method for separating a fuel pellet from a cladding tube.

[0006] On the one hand, an embodiment of the present application provides a device for separating a fuel pellet from a cladding tube, which may include a separation body, a cladding tube holder, an ejector, and a pellet collection assembly. The separation body forms a separation space. The cladding tube holder is used to hold the cladding tube, and the cladding tube holder is removably disposed in the separation space. The ejector is disposed in the separation body, and the ejector is configured to eject the fuel pellets in the cladding tube upward out of the cladding tube. The pellet collection assembly is configured to form a collection trough for collecting the fuel pellets ejected from the cladding tube, and the pellet collection assembly is removably disposed on a side of the cladding tube holder away from the ejector.

[0007] The separation device provided in the embodiment of the present application pushes the fuel core blocks in the cladding tube upward out of the cladding tube by arranging an ejection piece, thereby realizing separation of the fuel core blocks from the cladding tube in an ejection manner, and using a core block collection assembly to collect the fuel core blocks ejected from the cladding tube, which is beneficial to avoid the fuel core blocks from falling or moving due to breakage after irradiation during the separation process, thereby helping to improve the integrity of the fuel core blocks and further improve the accuracy of subsequent research results.

[0008] On the other hand, an embodiment of the present application further provides a method for separating a fuel pellet from a cladding tube, which is implemented using the separation device of the first aspect of the present application. The separation method may include placing the cladding tube to be separated on a cladding tube holder, and placing the cladding tube holder in a separation space; placing a pellet collection assembly in the separation space below the cladding tube holder; operating an ejector to abut the ejector against the cladding tube; rotating the separation body 180 degrees so that the ejector is located directly below the cladding tube; operating the ejector to allow the ejector to enter the cladding tube to eject the fuel pellet into the pellet collection assembly; rotating the separation body 180 degrees so that the ejector is located directly above the cladding tube; and removing the cladding tube holder and the pellet collection assembly from the separation space.

[0009] These and other advantages of the present application will become more apparent through the following detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to further illustrate the above and other advantages and features of the present application, the specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. The accompanying drawings together with the following detailed description are included in this specification and form a part of this specification. Elements with the same function and structure are represented by the same reference numerals. It should be understood that these drawings only describe typical examples of the present application and should not be regarded as limiting the scope of the present application.

[0011] Figure 1 is a schematic structural diagram of a device for separating a fuel pellet from a cladding tube according to an embodiment of the present application, wherein the ejector is located at a first position directly above the cladding tube retainer;

[0012] Figure 2 yes Figure 1 An exploded schematic diagram of the main body of the device for separating a fuel pellet from a cladding tube is shown;

[0013] Figure 3 yes Figure 1 A schematic cross-sectional view of the main body of the device for separating a fuel pellet from a cladding tube is shown;

[0014] Figure 4 yes Figure 1A schematic cross-sectional view of the main body of the device for separating a fuel pellet from a cladding tube is shown, wherein the cladding tube and the fuel pellet to be separated are placed in the cladding tube holder;

[0015] Figure 5 is a schematic structural diagram of a device for separating a fuel pellet from a cladding tube according to an embodiment of the present application, wherein the ejector is located at a second position directly below the cladding tube holder;

[0016] Figure 6 is a schematic structural diagram of a cladding tube holder according to an embodiment of the present application;

[0017] Figure 7 It is a schematic structural diagram of a pellet collection container according to one embodiment of the present application.

[0018] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding.

[0019] Description of reference numerals:

[0020] 10. Separation body; 101. Separation space; 11. Back plate; 12. First plate body; 13. Second plate body; 131. Sliding groove; 14. Rotation axis; 141. Positioning hole; 15. First magnetic attraction member; 16. Second magnetic attraction member;

[0021] 20. Cladding tube holder; 201. Cladding tube holding groove; 202. Step surface; 21. Cladding tube holding body; 22. Tube seat; 23. Cladding tube holding grip; 24. First magnetic fitting member;

[0022] 30. ejector; 31. first rod; 32. second rod; 33. ejector grip;

[0023] 40. Core block collection assembly; 41. Core block collection member; 411. Collection tank; 42. Core block collection container; 420. Collection container tank; 421. Collection container body; 422. Collection container grip; 423. Second magnetic attraction fitting member; 424. Position limiting member;

[0024] 50. Support member; 51. Base; 52. Support plate; 53. Connecting plate;

[0025] 60. Positioning member; 61. Threaded rod; 62. Positioning grip;

[0026] 71. Cladding tube; 72. Fuel pellet. DETAILED DESCRIPTION

[0027] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0028] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0029] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should have the common meanings understood by persons with ordinary skills in the field to which this application belongs.

[0030] In the description of the embodiments of the present application, “plurality” means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] The inventors of the present application have discovered that during service, fuel pellets may develop unpredictable cracks due to high fuel temperatures and large temperature gradients. In the related art, during the separation of the fuel pellets from the cladding tubes, the pellet fragments caused by these cracks may fall or move, affecting subsequent research on the distribution of fission products and radial microstructural changes of the fuel pellets.

[0032] In order to solve the above technical problems, an embodiment of the present application provides a device for separating a fuel pellet from a cladding tube (hereinafter referred to as a separation device).

[0033] See also Figures 1 to 4 , Figure 1 is a schematic structural diagram of a separation device according to an embodiment of the present application, wherein the ejector is located at a first position directly above the cladding tube holder, Figure 2 yes Figure 1 The exploded schematic diagram of the separation device shown in FIG. 1 , in which the support member and the positioning member are omitted, Figure 3 yes Figure 1 The schematic cross-sectional view of the separation device shown in FIG. 1 , in which the support member and the positioning member are omitted, Figure 4 yes Figure 1The schematic cross-sectional view of the separation device shown in the figure, wherein the cladding tube and the fuel pellets to be separated are placed in the support member and the cladding tube holder, and the separation device of the embodiment of the present application may include a separation body 10, a cladding tube holder 20, an ejector 30 and a pellet collection assembly 40. The separation body 10 forms a separation space 101. The cladding tube holder 20 is used to hold the cladding tube 71, and the cladding tube holder 20 is removably disposed in the separation space 101. The ejector 30 is disposed in the separation body 10, and the ejector 30 is configured to eject the fuel pellets 72 in the cladding tube 71 upward out of the cladding tube 71. The pellet collection assembly 40 is configured to form a collection groove 411 for collecting the fuel pellets 72 ejected from the cladding tube 71, and the pellet collection assembly 40 is removably disposed on the side of the cladding tube holder 20 away from the ejector 30.

[0034] Since the fuel pellets 72 are fractured after irradiation, if force is applied from above to move the fuel pellets 72 downward and away from the cladding tube 71, the fuel fragments ejected from the cladding tube 71 will fall into the collection groove 411 of the pellet collection assembly 40, which is very unfavorable for the fuel pellets 72 to maintain their original shape. The separation device provided in the embodiment of the present application pushes the fuel pellets 72 in the cladding tube 71 upward out of the cladding tube 71 by setting the ejector 30, and uses the pellet collection assembly 40 to collect the fuel pellets 72 ejected from the cladding tube 71, which is beneficial to avoid the fuel fragments of the fuel pellets 72 from falling or moving due to the fracture of the fuel pellets 72 after irradiation during the separation process, thereby improving the integrity of the fuel pellets 72, and further improving the accuracy of subsequent research results.

[0035] It is easy to understand that the cladding tube holder 20 and the pellet collection assembly 40 are removably disposed in the separation space 101, which means that the cladding tube holder 20 and the pellet collection assembly 40 can be taken out of the separation space 101, and the cladding tube holder 20 and the pellet collection assembly 40 can be placed in the separation space 101. The separation device provided in the embodiment of the present application is convenient for operation by a robot by removably disposing the cladding tube holder 20 in the separation space 101.

[0036] In some embodiments, the cladding tube holder 20 is in clearance fit with the cladding tube 71; the collecting groove 411 is in clearance fit with the fuel pellet 72; and the ejector 30 is configured to be able to enter the cladding tube 71 and be in clearance fit with the cladding tube 71. In such an embodiment, the fuel pellet 72 ejected by the ejector 30 does not undergo displacement of the broken pellets in the vertical direction, and since the ejected fuel pellet 72 enters the collecting groove 411 in clearance fit with it, it is possible to avoid radial displacement of the broken pieces of the fuel pellet 72 during the ejection process, thereby changing the original radial microstructure of the fuel pellet 72, thereby affecting the subsequent study of the distribution of fission products and the change of the radial microstructure of the fuel pellet 72.

[0037] The inventors of the present application have found that high burnup and fuel damage can cause the fuel pellets 72 to swell, resulting in changes in the diameter of the outer cladding tube 71 and the diameter of the inner fuel pellets 72. If fixed-size cladding tube holders 20 and pellet collection assemblies 40 are used, it may cause difficulties in the ejection process of the fuel pellets 72 or cause defects in the fuel pellets 72 or changes in the position of the pellet fragments. In response to this problem, in some embodiments, the separation device may include a plurality of cladding tube holders 20 and pellet collection assemblies 40 with different inner diameters, so as to select a cladding tube holder 20 with a suitable inner diameter size to hold the cladding tube 71, and select a pellet collection assembly 40 with a suitable inner diameter size to collect the fuel pellets 72.

[0038] This embodiment provides a cladding tube holder 20 of various sizes, and a cladding tube holder 20 matching the current cladding tube 71 diameter can be selected, which is conducive to the alignment of the cladding tube 71, the ejector 30 and the collecting groove 411, and ensures that the cladding tube holder 20 and the cladding tube 71 have clearance fit, the collecting groove 411 and the fuel pellet 72 have clearance fit, and the ejector 30 is set to be able to enter the cladding tube 71 and have clearance fit with the cladding tube 71, thereby ensuring that the fuel pellet 72 can smoothly enter the collecting groove 411 after being ejected, and avoid the fuel pellet 72 from being broken or displaced due to size mismatch. At the same time, the clearance fit between the cladding tube holder 20 and the cladding tube 71 can prevent the cladding tube 71 from falling off or shaking during the ejection process, and ensure that the cladding tube 71 remains stable during the separation process; the clearance fit between the collecting groove 411 and the outer diameter of the fuel pellet 72 can facilitate the fuel pellet 72 to smoothly enter the collecting groove 411, ensuring the integrity of the fuel pellet 72.

[0039] See also Figure 1 and Figure 5 , Figure 51 is a schematic diagram of the structure of a separation device according to an embodiment of the present application. In some embodiments, the separation device may further include a support member 50. The separation body 10 is rotatably disposed on the support member 50, and the separation body 10 is configured to be able to rotate relative to the support member 50 to a first position where the ejector 30 is located directly above the cladding tube holder 20 and a second position where the ejector 30 is located directly below the cladding tube holder 20. In the first position, the cladding tube holder 20 holding the cladding tube 71 is placed in the separation space 101 or removed from the separation space 101, and the pellet collection assembly 40 is placed in the separation space 101 or removed from the separation space 101. In the second position, the ejector 30 ejects the fuel pellet 72 in the cladding tube 71 from the bottom to the top. In this embodiment, the separation body 10 is configured to be rotatable relative to the support member 50, so that the ejector 30 can switch between the first position directly above the cladding tube holder 20 and the second position directly below the cladding tube holder 20, thereby optimizing the separation process of the fuel pellet 72 and the cladding tube 71. Specifically, before separating the fuel pellets 72 from the cladding tube 71, the separation body 10 can be rotated so that the ejector 30 is located in the first position, which can facilitate the placement of the cladding tube holder 20 and the pellet collection assembly 40 in the separation space 101; when the fuel pellets 72 are separated from the cladding tube 71, the separation body 10 can be rotated so that the ejector 30 is located in the second position, and the ejector 30 is used to eject the fuel pellets 72 in the cladding tube 71 from the cladding tube 71 from the bottom to the top, so as to achieve the separation of the cladding tube 71 and the fuel pellets 72; after the fuel pellets 72 are separated from the cladding tube 71, the separation body 10 can be rotated so that the ejector 30 is located in the first position, which can facilitate the removal of the cladding tube holder 20 and the pellet collection assembly 40 from the separation space 101.

[0040] See also Figures 2 to 5 In some embodiments, the ejector 30 may include a first rod 31 and a second rod 32 connected to the first rod 31. The inner diameter of the first rod 31 is smaller than the cladding tube 71, and the first rod 31 is in clearance fit with the cladding tube 71, so as to enter the cladding tube 71 and eject the fuel pellets 72. The second rod 32 is configured to be movably connected to the separation body 10, so as to drive the first rod 31 to move toward or away from the cladding tube 71. Before the separation body 10 rotates from the first position to the second position relative to the support member 50, the second rod 32 is operated to press the cladding tube 71 tightly. Since the inner diameter of the first rod 31 is smaller than the cladding tube 71 and the first rod 31 is in clearance fit with the cladding tube 71, the first rod 31 can accurately enter the cladding tube 71, effectively eject the fuel pellets 72, and help maintain the integrity of the fuel pellets 72. Before the separation body 10 rotates, the second rod 32 is operated to press the cladding tube 71 tightly, thereby preventing the cladding tube 71 from shaking due to the rotation of the separation body 10, thereby preventing the inner fuel pellets 72 from falling from the cladding tube 71.

[0041] See also Figures 1 to 5 In some embodiments, the ejector 30 may further include an ejector grip 33 connected to the second rod 32 for rotation by a manipulator, so that the ejection operation can be completed remotely by the manipulator to prevent the operator from being contaminated by radioactivity or being exposed to excessive radiation.

[0042] See also Figure 1 , Figure 2 and Figure 5 In some embodiments, the ejection grip portion 33 may be a cross hand wheel, so that it can be easily rotated by a robot.

[0043] See also Figure 1 and Figure 5 In some embodiments, the separation device may further include a positioning member 60. The positioning member 60 is used to position the separation body 10 when the separation body 10 rotates to the first position and the second position relative to the support member 50, respectively, so as to prevent the separation body 10 from rotating relative to the support member 50. In such an embodiment, by providing the positioning member 60, it is ensured that when the ejection member 30 applies force to the fuel pellets 72 in the cladding tube 71, the separation body 10 of the cladding tube 71 is prevented from rotating.

[0044] See also Figure 1 and Figure 5 In some embodiments, the positioning member 60 may further include a threaded rod 61 and a positioning grip 62. The connecting plate 53 is provided with a threaded hole matched with the threaded rod 61, and the threaded rod 61 passes through the threaded hole and is threadedly connected to the connecting plate 53. The positioning grip 62 is used for the robot to operate and rotate. When the robot rotates the positioning grip 62, the threaded rod 61 moves relative to the connecting plate 53 toward or away from the positioning hole 141.

[0045] See also Figure 1 , Figure 2 and Figure 5In some embodiments, the separation body 10 may include a back plate 11, two first plates 12 arranged opposite to each other, two second plates 13 arranged opposite to each other, and a rotating shaft 14. The two first plates 12 are connected to the back plate 11, and the two second plates 13 are connected to the back plate 11 and are simultaneously connected to the two first plates 12. The back plate 11, the two first plates 12, and the two second plates 13 together form a separation space 101. The rotating shaft 14 is connected to the back plate 11, and the rotating shaft 14 can rotate relative to the support member 50. The ejector 30 is provided on a first plate 12. The back plate 11 in this embodiment is connected to the two first plates 12 and the two second plates 13 on both sides to form a stable frame, which ensures the structural strength of the separation space 101, so that the separation space 101 will not be deformed during operation. Since the rotating shaft 14 is connected to the back plate 11, the separation body 10 can rotate relative to the support member 50. At the same time, the ejector 30 is disposed on the first plate body 12 so that the ejector 30 can eject the fuel pellets 72 from a vertical direction.

[0046] See also Figure 1 and Figure 5 In some embodiments, the support member 50 may include a base 51 and a support plate 52 disposed on the base 51. The separation body 10 is rotatably connected to the support plate 52 via a rotation shaft 14. The base 51 and the support plate 52 in this embodiment provide a stable support for the separation body 10, and the separation body 10 is rotatably connected to the support plate 52 via the rotation shaft 14, so that the separation body 10 can rotate relative to the support plate 52 to a first position and a second position.

[0047] See also Figure 1 and Figure 5 In some embodiments, the support member 50 may further include a connecting plate 53 connected to the support plate 52 for mounting the positioning member 60, providing a stable mounting platform for the positioning member 60 so that the positioning member 60 can position the separation body 10. In some embodiments, the positioning member 60 is threadedly connected to the connecting plate 53.

[0048] See also Figure 2 In some embodiments, a positioning hole 141 is formed on the rotating shaft 14 , and the positioning member 60 enters the positioning hole 141 for positioning to limit the rotation of the rotating shaft 14 .

[0049] In some embodiments, two positioning holes 141 are formed on the rotating shaft 14, and the two positioning holes 141 are arranged on the radial sides of the rotating shaft 14 opposite to each other. The support member 50 may also include two connecting plates 53, which are arranged on the radial sides of the rotating shaft 14 opposite to each other. The two positioning members 60 pass through a corresponding connecting plate 53 respectively. The two positioning members 60 extend in the horizontal direction, and the connecting line of the two positioning holes 141 is perpendicular to the axis of the ejector 30. When the separation body 10 is in the first position or the second position, the two positioning members 60 enter the corresponding positioning holes 141 to position the separation body 10. In such an embodiment, the separation body 10 only needs to be rotated so that the positioning holes 141 face the positioning members 60, so that the separation body 10 can be in the first position or the second position.

[0050] See also Figures 1 to 5 In some embodiments, the second rod 32 is provided with a thread; the first plate 12 provided on the ejector 30 is provided with a threaded hole, the first rod 31 passes through the threaded hole to enter the separation space 101, and the second rod 32 enters the threaded hole and is threadedly connected with the first plate 12. By rotating the second rod 32, the second rod 32 can move relative to the first plate 12 toward the cladding tube holder 20, thereby entering the cladding tube 71 to eject the fuel pellet 72. By rotating the second rod 32 to eject the fuel pellet 72, it is more advantageous to control the drilling rate of the second rod 32 in the cladding tube 71, so that the fuel pellet 72 slowly extends from the cladding tube 71 and slowly enters the collection tank 411, thereby preventing the original cracks of the fuel pellet 72 from continuing to crack.

[0051] See also Figure 2 In some embodiments, the two second plates 13 further form two sliding grooves 131 arranged opposite to each other, and the cladding tube holder 20 can be slidably arranged in the sliding grooves 131, so that the cladding tube holder 20 can be axially positioned in the separation space 101 without affecting the placement and removal of the pellet collection assembly 40 below. At the same time, it can also avoid applying force to the pellet collection assembly 40 in the process of ejecting the fuel pellets 72 by using the ejector 30, causing damage to the pellet collection assembly 40.

[0052] See also Figure 4In some embodiments, the pellet collection assembly 40 may include a pellet collection member 41 and a pellet collection container 42. The pellet collection member 41 forms a collection groove 411. The pellet collection container 42 is used to accommodate the pellet collection member 41, and the pellet collection container 42 is removably disposed on a side of the cladding tube holder 20 away from the ejector 30. In such an embodiment, the pellet collection container 42 is used to cooperate with the separation space 101, and the pellet collection member 41 is used to cooperate with the fuel pellets 72. The size of the inner diameter of the pellet collection member 41 can be selected according to the size of the fuel pellets 72, and it is also convenient to directly take out the pellet collection member 41 containing the fuel pellets 72 for subsequent processing of the fuel pellets 72.

[0053] In some embodiments, the pellet collector 41 is a crucible made of graphite. In such an embodiment, since graphite material cannot bear weight, the cladding tube holder 20 is arranged on the two second plates 13 through the sliding groove 131. When the ejector 30 applies force to eject the fuel pellets 72, the pellet collector 41 will not be subjected to force, thereby avoiding damage to the pellet collector 41.

[0054] See also Figure 4 In some embodiments, the two second plates 13 are clearance-matched with the cladding tube holder 20 and the pellet collection container 42, which facilitates the alignment of the cladding tube holder 20 and the pellet collection container 41, and also facilitates the placement of the cladding tube holder 20 and the pellet collection container 42 in the separation space 101 or removal from the separation space 101.

[0055] See also Figures 1 to 3In some embodiments, the separation body 10 may further include a first magnetic member 15 and a second magnetic member 16. The first magnetic member 15 and the second magnetic member 16 are arranged at different heights of the back plate 11. The cladding tube holder 20 is correspondingly provided with a first magnetic fitting member 24, so that the cladding tube 71 held in the cladding tube holder 20 is aligned with the ejector 30 through the first magnetic fitting member 24 and the first magnetic member 15. The core block collection assembly 40 is correspondingly provided with a second magnetic fitting member 423, so that the collection slot 411 of the core block collection assembly 40 is aligned with the ejector 30 through the second magnetic fitting member 423 and the second magnetic member 16. In such an embodiment, when the cladding tube holder 20 and the pellet collection container 42 are placed into the separation space 101 by a manipulator, different gaps may exist between the cladding tube holder 20 and the pellet collection container 42 and the back plate 11, which may cause the pellet collection component 41, the cladding tube holder 20 and the ejector 30 to be misaligned, thereby causing radial movement or deformation of the fuel pellets 72 during the ejection process. The embodiment of the present application can stably fix the cladding tube holder 20 and the pellet collection assembly 40 to the back plate 11 by magnetic attraction, so that the cladding tube holder 20 and the pellet collection component 41 can be efficiently and accurately aligned with the ejector 30, thereby ensuring the integrity of the fuel pellets 72.

[0056] See also Figure 3 In some embodiments, the cladding tube retaining member 20 forms a penetrating cladding tube retaining groove 201, and a step surface 202 is formed on the side of the cladding tube retaining groove 201 away from the ejection member 30, which is used to prevent the cladding tube 71 from falling off and allow the fuel pellets 72 to pass through, so that when the ejection member 30 ejects the fuel pellets 72, the cladding tube 71 can be stably maintained in the cladding tube retaining groove 201, and the fuel pellets 72 are ejected from the cladding tube 71 by the ejection member 30 into the collecting groove 411.

[0057] See also Figure 3 and Figure 6 , Figure 6 2 is a schematic diagram of the structure of the cladding tube holder 20. In some embodiments, the cladding tube holder 20 may include a cladding tube holder body 21 and a tube seat 22 disposed on the cladding tube holder body 21. The cladding tube holder body 21 and the tube seat 22 together form a cladding tube holder groove 201. A step surface 202 is formed on the cladding tube holder body 21. The cladding tube holder body 21 in this embodiment is used to cooperate with the separation space 101, and the tube seat 22 is used to provide a holding effect for the cladding tube 71, so that the cladding tube 71 can be stably placed in the cladding tube holder groove 201. The step surface 202 can effectively prevent the cladding tube 71 from falling off, and ensure that the fuel pellet 72 can be ejected from the cladding tube 71.

[0058] In some embodiments, the cladding tube retaining groove 201 may be 0.1 mm larger than the outer diameter of the cladding tube 71 , and the inner diameter of the step surface 202 may be consistent with the inner diameter of the cladding tube 71 .

[0059] See also Figures 1 to 6 In some embodiments, the cladding tube holder 20 may further include a cladding tube holding gripping portion 23, which is connected to the cladding tube holding body 21 for operation by a manipulator, so that the operation of placing and removing the cladding tube holder 20 can be completed remotely by the manipulator, thereby preventing the operator from being contaminated by radioactivity or being exposed to excessive radiation.

[0060] See also Figure 1 and Figure 5 In some embodiments, the cladding tube holding body 21 is gap-fitted with the two second plates 13. The first magnetic fitting member 24 is disposed on the cladding tube holding body 21, so that the cladding tube holding member 20 can be stably fixed to the back plate 11 and aligned with the ejector 30. In some embodiments, two first magnetic fitting members 24 are disposed on the cladding tube holding body 21, further strengthening the stable connection between the cladding tube holding member 20 and the back plate 11.

[0061] See also Figure 3 and Figure 7 , Figure 7 Schematic diagram of the structure of the core block collection assembly. In some embodiments, the core block collection container 42 may include a collection container body 421, and the collection container body 421 forms a collection container slot 420. The second magnetic attraction fitting 423 is provided on the collection container body 421, so that the core block collection container 42 can be stably fixed to the back plate 11, and the collection slot 411 can be aligned with the ejector 30. In some embodiments, two second magnetic attraction fittings 423 are provided on the collection container body 421, further strengthening the stable connection between the collection container assembly and the back plate 11.

[0062] See also Figure 7 In some embodiments, the core block collection container 42 may further include a collection and storage gripping portion 422, which is connected to the collection and storage body 421 and is used for robot operation, so that the operation of placing and removing the core block collection container 42 can be completed remotely by the robot, thereby preventing the operator from being contaminated by radioactivity or being exposed to excessive radiation.

[0063] See also Figure 7 In some embodiments, the pellet collecting container 42 may further include a stopper 424 . The stopper 424 abuts against the two second plates 13 .

[0064] The embodiments of the present application also provide a method for separating the fuel pellet 72 from the cladding tube 71 , which can be implemented using the separation device in any embodiment of the present application. The separation method includes the following steps S1 to S7 .

[0065] In step S1 , the cladding tube 71 to be separated is placed in the cladding tube holder 20 , and the cladding tube holder 20 is placed in the separation space 101 .

[0066] In step S2 , the pellet collection assembly 40 is placed in the separation space 101 below the cladding tube holder 20 .

[0067] In step S3 , the ejector 30 is operated so as to make the ejector 30 contact the cladding tube 71 .

[0068] In step S4 , the separation body 10 is rotated 180 degrees so that the ejector 30 is located directly below the cladding tube 71 .

[0069] In step S5 , the ejector 30 is operated to enter the cladding tube 71 to eject the fuel pellets 72 into the pellet collection assembly 40 .

[0070] In step S6 , the separation body 10 is rotated 180 degrees so that the ejector 30 is located directly above the cladding tube 71 .

[0071] In step S7 , the cladding tube holder 20 and the pellet collection assembly 40 are taken out from the separation space 101 .

[0072] The separation method provided in the embodiment of the present application is achieved by rotating the separation body 10 180 degrees so that the ejector 30 is located below the cladding tube holder 20, and using the ejector 30 to eject the fuel pellets 72 in the cladding tube 71 upward out of the cladding tube 71, and using the pellet collection assembly 40 to collect the fuel pellets 72 ejected from the cladding tube 71. This is beneficial in preventing the fuel pellets 72 from falling or moving due to fracture after irradiation during the separation process, thereby helping to improve the integrity of the fuel pellets 72, and further improve the accuracy of subsequent research results.

[0073] In some embodiments, the cladding tube 71 to be separated in step S1 is a fuel short rod with an outer layer of zirconium alloy.

[0074] Due to high burnup and fuel damage, the fuel pellets 72 will swell, affecting the diameter of the cladding tube 71, making it difficult to ensure that the fuel pellets 72 remain intact after being separated from the cladding tube 71. In view of the above problems, in some embodiments, the method for separating the fuel pellets from the cladding tube provided by the embodiments of the present application further includes: S0, measuring the wall thickness of the cladding tube 71 and the outer diameter of the cladding tube 71, determining the outer diameter of the fuel pellets 72 according to the wall thickness of the cladding tube 71 and the outer diameter of the cladding tube 71, and determining the inner diameter size of the cladding tube holder 20 and the pellet collector 41 according to the outer diameter of the cladding tube 71 and the outer diameter of the fuel pellets 72. In such an embodiment, by measuring the wall thickness of the cladding tube 71 and the outer diameter of the cladding tube 71, a cladding tube holder 20 matching the size of the current cladding tube 71 and a pellet collector 41 matching the size of the current fuel pellet 72 can be selected, which is beneficial to aligning the cladding tube 71, the ejector 30 and the collecting groove 411, and ensures that the cladding tube holder 20 and the cladding tube 71 have a clearance fit, the collecting groove 411 and the fuel pellet 72 have a clearance fit, and the ejector 30 is configured to be able to enter the cladding tube 71 and have a clearance fit with the cladding tube 71, thereby ensuring that the fuel pellet 72 can smoothly enter the collecting groove 411 after being ejected, and avoiding the fuel pellet 72 from being broken or displaced due to size mismatch. At the same time, the clearance fit between the cladding tube retainer 20 and the cladding tube 71 can prevent the cladding tube 71 from falling off or shaking during the ejection process, and ensure that the cladding tube 71 remains stable during the separation process; the clearance fit between the collecting groove 411 and the outer diameter of the fuel pellet 72 can facilitate the fuel pellet 72 to smoothly enter the collecting groove 411, thereby ensuring the integrity of the fuel pellet 72.

[0075] The method for separating the fuel pellet 72 from the cladding tube 71 according to the embodiment of the present application is further described below by way of a specific embodiment.

[0076] (1) First, use a vernier caliper to measure the wall thickness and outer diameter of the cladding tube 71 to be separated, and the measured outer diameter of the cladding tube 71 to be separated is 9.5 mm, and the wall thickness is 0.57 mm; then, based on the measured wall thickness and outer diameter of the cladding tube 71 to be separated, calculate the outer diameter of the fuel pellet 72, and calculate the outer diameter of the fuel pellet 72 to be 8.36 mm; then, based on the outer diameter of the cladding tube 71 and the calculated outer diameter of the fuel pellet 72, select a cladding tube holder 20 and a pellet collector 41 with appropriate inner diameter sizes. A cladding tube holder 20 with an inner diameter of 9.6 mm can be selected to ensure that the inner diameter of the cladding tube holder 20 and the cladding tube 71 have a clearance fit. A pellet collector 41 with an inner diameter of 8.5 mm can be selected, and the inner diameter of the pellet collector 41 has a clearance fit with the outer diameter of the fuel pellet 72.

[0077] (2) After ensuring that the ejector 30 is located directly above the cladding tube holder 20, use the robot to operate the positioning member 60 to position the separation body 10 to prevent the separation body 10 from rotating relative to the support member 50; then place the cladding tube 71 to be separated into the selected cladding tube holder 20; and then use the robot to place the cladding tube holder 20 with the cladding tube 71 into the separation space 101.

[0078] (3) The pellet collection assembly 40 is placed in the separation space 101 below the cladding tube holder 20 by a robot.

[0079] (4) The ejector 30 is rotated by the manipulator so that the ejector 30 slightly contacts the cladding tube 71 to ensure that excessive force is not applied to avoid damaging the cladding tube 71 or the fuel pellets 72 .

[0080] (6) The separation body 10 is rotated 180 degrees by the manipulator so that the ejector 30 is located directly below the cladding tube 71 ; the separation body 10 is positioned by operating the positioning member 60 by the manipulator to prevent the separation body 10 from rotating relative to the support member 50 .

[0081] (7) The manipulator operates the ejector 30 again, so that the ejector 30 slowly and evenly enters the interior of the cladding tube 71 and ejects the fuel pellet 72. During the ejection process, the force applied is adjusted to ensure a smooth ejection process to protect the integrity of the fuel pellet 72. When the ejected fuel pellet 72 falls into the collection groove 411 of the collection assembly, check whether the fuel pellet 72 is intact and whether it has completely entered the collection groove 411.

[0082] (8) The separation body 10 is rotated 180 degrees by a robot operation so that the ejector 30 returns from directly below the cladding tube 71 to directly above the cladding tube 71; the positioning member 60 is then operated by the robot to position the separation body 10 to prevent the separation body 10 from rotating relative to the support member 50; and the cladding tube retainer 20 and the core block collection assembly 40 are removed from the separation space 101 by the robot.

[0083] (9) The pellet collection member 41 containing the separated fuel pellets 72 in the pellet collection assembly 40 is removed from the pellet collection container 42, and the microstructure of the fuel pellets 72 is observed under a microscope to analyze the distribution of fission products; various experimental data and analysis results are recorded in detail, which may include the type, content, distribution and release behavior of the fission products; the data is sorted and analyzed to analyze the distribution and release behavior of the fission products of the fuel pellets 72.

[0084] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0085] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A device for separating a fuel pellet from a cladding tube, characterized in that: include: A separation body, wherein the separation body forms a separation space; A cladding tube holder, used for holding the cladding tube, wherein the cladding tube holder is removably disposed in the separation space; An ejector, disposed on the separation body, and configured to eject the fuel pellets in the cladding tube upward out of the cladding tube; A pellet collecting assembly is arranged to form a collecting trough for collecting the fuel pellets ejected from the cladding tube. The pellet collecting assembly is removably arranged on a side of the cladding tube holder away from the ejecting member.

2. The device according to claim 1, characterized in that Also includes: A support member, the separation body is rotatably arranged on the support member, and the separation body is arranged to be able to rotate relative to the support member to a first position where the ejector is located directly above the cladding tube holder and a second position where the ejector is located directly below the cladding tube holder; wherein, in the first position, the cladding tube holder holding the cladding tube is placed in the separation space or removed from the separation space, and the pellet collection assembly is placed in the separation space or removed from the separation space; In the second position, the ejector pushes the fuel pellets in the cladding tube out of the cladding tube from bottom to top.

3. The device according to claim 2, characterized in that The ejector member includes a first rod and a second rod connected to the first rod, the first rod having an inner diameter smaller than the cladding tube and having a clearance fit with the cladding tube so as to enter the cladding tube and eject the fuel pellets, and the second rod is configured to be movably connected to the separation body so as to drive the first rod to move toward or away from the cladding tube; Wherein, before the separation body rotates from the first position to the second position relative to the support member, the second rod is operated to tighten the cladding tube.

4. The device according to claim 2, characterized in that Also includes: A positioning member, wherein the positioning member is used to position the separation body when the separation body rotates to the first position and the second position relative to the support member, so as to prevent the separation body from rotating relative to the support member.

5. The device according to claim 2, characterized in that The separation subject comprises: A back plate, two first plates arranged opposite to each other, and two second plates arranged opposite to each other, wherein the two first plates are connected to the back plate, and the two second plates are connected to the back plate and to the two first plates at the same time, and the back plate, the two first plates and the two second plates together form the separation space; A rotating shaft connected to the back plate, the rotating shaft being rotatable relative to the supporting member; Wherein, the ejector is arranged on one of the first plates.

6. The device according to claim 5, characterized in that The two second plates further form two sliding grooves arranged opposite to each other, and the cladding tube holder is slidably arranged in the sliding grooves.

7. The device according to claim 6, characterized in that The separation body further comprises: a first magnetic attraction member and a second magnetic attraction member, which are arranged at different heights of the back plate; The cladding tube holder is correspondingly provided with a first magnetic attraction fitting part, so that the cladding tube held in the cladding tube holder is aligned with the ejection part through magnetic attraction between the first magnetic attraction fitting part and the first magnetic attraction part; The core block collecting assembly is correspondingly provided with a second magnetic attraction fitting part, so that the collecting groove of the core block collecting assembly is aligned with the ejection part through magnetic attraction between the second magnetic attraction fitting part and the second magnetic attraction part.

8. The device according to claim 7, characterized in that The pellet collection assembly comprises: a pellet collecting member and a pellet collecting receiving member; The pellet collecting member forms the collecting trough; The pellet collecting and accommodating member is used to accommodate the pellet collecting member, and the pellet collecting and accommodating member is removably disposed on a side of the cladding tube holding member away from the ejecting member.

9. The device according to claim 1, characterized in that The cladding tube retaining member forms a penetrating cladding tube retaining groove, and a side of the cladding tube retaining groove away from the ejection member forms a step surface for preventing the cladding tube from falling off and allowing the fuel pellets to pass through.

10. A method for separating a fuel pellet from a cladding tube, characterized in that: The method is implemented using the device described in any one of claims 2 to 9, and the method comprises: Placing the cladding tube to be separated on the cladding tube holder, and placing the cladding tube holder in the separation space; placing the pellet collection assembly in the separation space below the cladding tube holder; operating the ejector to abut against the cladding tube; Rotate the separation body 180 degrees so that the ejector is located directly below the cladding tube; operating the ejector to allow the ejector to enter the cladding tube and eject the fuel pellets into the pellet collection assembly; Rotate the separation body 180 degrees so that the ejector is located directly above the cladding tube; The cladding tube holder and the pellet collection assembly are removed from the separation space.

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