An underwater storage device for damaged pipe sections of spent fuel assemblies

Abstract

The present invention provides an underwater storage device for damaged pipe sections of spent fuel assemblies, comprising: a storage tube placed in a storage cavity of a water tank storage grid; a sealing cover detachably connected to the upper end of the storage tube via a plurality of connecting bolts; a remote disassembly assembly for disassembling and installing the plurality of connecting bolts; an inflation assembly disposed on the surface of the sealing cover, the gas outlet of the inflation assembly communicating with the storage tube; and a drainage assembly disposed on the surface of the sealing cover, the water inlet of the drainage assembly communicating with the storage tube. The present invention utilizes the remote disassembly assembly to remove the connecting bolts and separate the sealing cover from the storage tube. The damaged pipe section of the spent fuel assembly is placed in the storage tube via salvaging equipment, the sealing cover and the storage tube are connected, and the water inside the storage tube is drained via the inflation assembly and drainage assembly. This allows for the cleaning and storage of debris such as the outer shell and fuel pipe section after the spent fuel assembly falls and disintegrates, thereby preventing radioactive leakage.

Description

Technical Field

[0001] The invention relates to the technical field of spent fuel assembly processing, in particular to an underwater storage device for damaged pipe sections of spent fuel assemblies. Background Art

[0002] The main task of the spent fuel receiving and storage facility is to receive spent fuel transport containers delivered from the nuclear power plant, unload the spent fuel assemblies underwater, and transport them to the storage grids in the storage pool for storage. During the unloading process, the spent fuel assemblies must be grasped by a spent fuel assembly gripper and transferred through waterways to the designated storage grid storage sleeves for storage. During this process, there is a risk of the spent fuel assemblies falling. If a spent fuel assembly falls, it may collide, be squeezed, or scratched during the fall, causing the spent fuel assembly to rupture and disintegrate, resulting in the scattering of spent fuel assembly fuel tube sections and cladding fragments on the pool bottom. If not cleaned and salvaged in a timely manner, the release of radioactive nuclides will continue, leading to a continuous increase in radioactivity levels on the pool bottom and in the pool hall.

[0003] Due to the high radioactivity of spent fuel assemblies, fuel tube sections and cladding fragments that are partially disintegrated and damaged after falling into the storage pool, as well as the complex underwater environment and limited space, there is currently no dedicated collection and storage device for nuclear fuel assemblies that are partially damaged and disintegrated at the bottom of the storage pool, as well as the scattered shells, fuel tube sections and other fragments of spent fuel assemblies. Therefore, it is unable to cope with the cleaning and storage of shells, fuel tube sections and other fragments after the spent fuel assemblies fall and disintegrate. Summary of the Invention

[0004] The present invention provides an underwater collection and storage device for damaged pipe sections of spent fuel assemblies. Connecting bolts are removed by remote disassembly and assembly components, and a sealing cover and a storage tube are separated. The damaged pipe section of the spent fuel assembly is placed in the storage tube by salvaging equipment, and the sealing cover and the storage tube are connected. Water in the storage tube is drained by an inflation component and a drainage component, thereby enabling the cleaning and storage of debris such as the outer shell and the fuel pipe section after the spent fuel assembly falls and disintegrates, thereby preventing radioactive leakage.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] An underwater storage device for damaged pipe sections of spent fuel assemblies, comprising:

[0007] a storage tube placed in the storage cavity of the water tank storage grid;

[0008] a sealing cover detachably connected to the upper end of the storage tube via a plurality of connecting bolts;

[0009] Remote disassembly and assembly components for disassembling and installing multiple connecting bolts;

[0010] A detachable inflation component, the inflation component is arranged on the surface of the sealing cover, and the gas outlet end of the inflation component is connected to the storage tube;

[0011] A detachable drainage component is arranged on the surface of the sealing cover, and the water inlet end of the drainage component is connected to the storage pipe.

[0012] Optionally, the inflatable component includes:

[0013] a first male connector connected to an air inlet on a surface of the sealing cover, wherein the air inlet is in communication with the storage tube;

[0014] a first female connector pluggable with the first male connector;

[0015] an air inlet pipe, wherein the air inlet end of the air inlet pipe is connected to the air source, and the air outlet end of the air inlet pipe is connected to the first female connector;

[0016] A first remote disconnect assembly is connected to the first female connector.

[0017] Optionally, the drainage component includes:

[0018] a second male connector connected to a drainage hole on a surface of the sealing cover;

[0019] a liquid guide tube, wherein a first end of the liquid guide tube is connected to the drainage hole, and a second end of the liquid guide tube extends to the inner bottom surface of the storage tube;

[0020] a second female connector pluggable with the second male connector;

[0021] a drain pipe, wherein the water inlet end of the drain pipe is connected to the second female connector;

[0022] A second remote disconnect assembly is connected to the second female connector.

[0023] Optionally, both the first remote separation component and the second remote separation component include:

[0024] a connecting ring, the inner diameter of which matches the outer diameters of the first female connector and the second female connector;

[0025] A first ear plate and a second ear plate are respectively formed at both ends of the opening of the connecting ring, and the first ear plate and the second ear plate are connected by a fastening bolt and a fastening nut;

[0026] A portal frame connected to the connecting ring;

[0027] A lifting ring connected to the portal frame;

[0028] A rope connected to the lifting ring.

[0029] Optionally, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0030] A connecting plate formed on the edge of the upper end of the storage tube has a plurality of threaded holes formed through the surface of the connecting plate. The plurality of threaded holes are evenly distributed around the circumference of the storage tube axis, and the plurality of threaded holes are adapted to a plurality of connecting bolts.

[0031] A plurality of connecting through holes are provided through the surface of the sealing cover. The plurality of connecting through holes correspond to the plurality of threaded holes. The plurality of connecting bolts are located in the plurality of connecting through holes.

[0032] Optionally, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0033] An annular groove formed on the surface of the connecting plate, the annular groove being distributed on the outer side of the upper end of the storage tube;

[0034] A sealing ring is embedded in the annular groove, and a portion of the sealing ring protrudes from the upper surface of the connecting disk.

[0035] Optionally, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0036] A clamping end connected to the sealing cover.

[0037] Optionally, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0038] A one-way exhaust valve is connected to the upper surface of the sealing cover, and an air inlet end of the one-way exhaust valve is communicated with the storage tube.

[0039] Optionally, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0040] A reinforcing plate connected to the bottom surface of the storage tube abuts against the bottom surface of the storage cavity of the water tank storage grid.

[0041] Optionally, the remote disassembly assembly component includes:

[0042] A top threaded rod, wherein the top end of the top threaded rod is connected to an operating handle;

[0043] multiple mid-threaded rods;

[0044] Bottom threaded rod;

[0045] The outer sides of the top threaded rod, the plurality of middle threaded rods and the bottom threaded rod are all threadedly connected with connecting sleeves;

[0046] A screwing block is connected to the bottom end of the bottom threaded rod. A contoured cavity is formed on the bottom surface of the screwing block, and the contoured cavity is adapted to the screwing end of the connecting bolt.

[0047] The above solution of the present invention includes at least the following beneficial effects:

[0048] The above solution of the present invention realizes the removal of the connecting bolts through the remote disassembly assembly to achieve the separation of the sealing cover and the storage tube. The damaged pipe section of the spent fuel assembly is placed in the storage tube by using the salvage equipment. The sealing cover and the storage tube are connected. The water in the storage tube is drained by the inflation assembly and the drainage assembly. Thus, the debris of the shell, fuel pipe section, etc. after the spent fuel assembly falls and disintegrates can be cleaned and stored, thereby preventing radioactive leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 1. It is a schematic structural diagram of an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention;

[0050] Figure 2 2. It is a top view of an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention;

[0051] Figure 3 1. It is a top view of a storage tube in an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention;

[0052] Figure 4 This is a structural schematic diagram of a remote disassembly and assembly component in an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention;

[0053] Figure 5 1 is a schematic structural diagram of a first remote separation assembly and a second remote separation assembly in an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention;

[0054] Figure 6 It is a top view of a first remote separation assembly and a second remote separation assembly in an underwater storage device for damaged pipe sections of spent fuel assemblies provided by an embodiment of the present invention.

[0055] The following are the descriptions of the reference numerals:

[0056] 1. Storage tube; 11. Connecting plate; 12. Threaded hole; 13. Annular groove; 14. Sealing ring; 15. Reinforcement plate; 2. Sealing cover; 21. Clamping end; 22. Air inlet; 23. Drain hole; 24. Connecting through hole; 31. First male connector; 41. Second male connector; 42. Liquid guide tube; 5. Connecting bolt; 6. One-way exhaust valve; 71. Top threaded rod; 72. Bottom threaded rod; 73. Connecting sleeve; 74. Operating handle; 75. Screw block; 76. Profiling cavity; 81. Connecting ring; 82. Door frame; 83. Lifting ring; 84. First ear plate; 85. Second ear plate; 86. Fastening bolt; 87. Fastening nut; 9. Water tank storage grid. DETAILED DESCRIPTION

[0057] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0058] like Figures 1 to 6 As shown, an embodiment of the present invention provides an underwater storage device for damaged pipe sections of spent fuel assemblies, comprising:

[0059] A storage tube 1 placed in the storage cavity of the water tank storage grid 9;

[0060] A sealing cover 2 is detachably connected to the upper end of the storage tube 1 via a plurality of connecting bolts 5;

[0061] Remote disassembly and assembly components for disassembling and installing multiple connecting bolts 5;

[0062] A detachable inflatable component is provided on the surface of the sealing cover 2, and the air outlet end of the inflatable component is connected to the storage tube 1;

[0063] A detachable drainage assembly is provided on the surface of the sealing cover 2 , and the water inlet end of the drainage assembly is connected to the storage pipe 1 .

[0064] In this embodiment, under normal conditions, the storage tube 1 is placed in the storage cavity of the water tank storage grid 9, and the sealing cover 2 is connected to the upper end of the storage tube 1 to seal the storage tube 1;

[0065] When there are fragments of partially damaged and disintegrated nuclear fuel assemblies and scattered shells, fuel pipe sections, etc. of spent fuel assemblies at the bottom of the storage pool, multiple connecting bolts 5 are removed by remote disassembly components to release the connection between the sealing cover 2 and the upper end of the storage tube 1. The sealing cover 2 is clamped and removed by the salvage equipment, and the inflation component and the drainage component are installed. The fragments of partially damaged and disintegrated nuclear fuel assemblies and scattered shells, fuel pipe sections, etc. of spent fuel assemblies are clamped and salvaged by the salvage equipment and placed in the storage tube 1. After all the fuel is stored in the storage tube 1, the sealing cover 2 is placed on the upper end of the storage tube 1 using the salvage equipment. The multiple connecting bolts 5 are screwed through the remote disassembly assembly to connect the sealing cover 2 to the upper end of the storage tube 1, thereby sealing the storage tube 1. The storage tube 1 is then inflated with air through the inflation assembly. Under the action of the air pressure, the water in the storage tube 1 is drained through the drainage assembly. After the water in the storage tube 1 is drained, the inflation assembly and drainage assembly are disassembled to complete the collection and storage of the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly, thereby preventing radioactive leakage.

[0066] In this embodiment, the shape of the storage tube 1 is adapted to the shape of the storage cavity of the water storage grid 9 to ensure the stability of the storage tube 1 in the storage cavity of the water storage grid 9 and to ensure the stability and safety of the storage tube 1. Specifically, the storage tube 1 has a length of 222 mm, a width of 222 mm, a height of 4400 mm, and a wall thickness of 3 mm.

[0067] The salvage equipment in this embodiment includes a spent fuel assembly salvage device and an underwater foreign body salvage tool, both of which are existing tools.

[0068] The upper end of the spent fuel assembly salvage device is connected to a dedicated hoisting position of the crane. The lower end of the spent fuel assembly salvage device is bolted upward to the connecting rod. The device is equipped with an underwater camera, two waterproof servo motors, an angle adjustment gear, a pitch adjustment gear, a positioning plate, a grab plate, a safety pin and other devices. The lower end of the device can perform various actions such as rotation, upward tilt, downward tilt, fixation, grabbing, and locking control, thereby completing the clamping and removal of the sealing cover 2 and the clamping and storage of the spent fuel assembly in the storage tube 1.

[0069] The main structure of the underwater foreign body salvage tool consists of a wire winding mechanism, a connecting rod, and a grab head component; the shape, type, and depth of the foreign body dropped into the pool can be observed through an underwater observation mirror. After determining the length, material, and type of the claws of the connecting parts of the underwater foreign body salvage device, the connecting rods are connected section by section, and fastened to the grab head component through a quick connector connecting the wire rope. By controlling the two independent wire winding mechanisms on the operating handle, the scattered shell fragments and fuel pipe sections are clamped one by one and placed in the storage tube 1.

[0070] like Figure 1 As shown, in an optional embodiment of the present invention, the inflatable component includes:

[0071] A first male connector 31 is connected to the air inlet 22 on the surface of the sealing cover 2, and the air inlet 22 is connected to the storage tube 1;

[0072] A first female connector that plugs and mates with the first male connector 31;

[0073] An air inlet pipe, wherein the air inlet end of the air inlet pipe is connected to the air source, and the air outlet end of the air inlet pipe is connected to the first female connector;

[0074] A first remote disconnect assembly is coupled to the first female connector.

[0075] In this embodiment, the first male connector 31 and the first female connector are respectively the male connector and the female connector of the quick connector. The first male connector 31 is in a sealed state under normal conditions. After the first female connector is plugged into the first male connector 31, the first female connector and the first male connector 31 are in communication.

[0076] The first male connector 31 is connected to the air inlet 22. After the sealing cover 2 is removed from the water tank using salvaging equipment, the first female connector is plugged into the first male connector 31 to connect the air inlet pipe to the first male connector 31. The first remote separation assembly is connected to the first female connector.

[0077] After all the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly are stored in the storage tube 1, the sealing cover 2 is placed on the upper end of the storage tube 1 using salvage equipment, and multiple connecting bolts 5 are screwed through the remote disassembly assembly to connect the sealing cover 2 to the upper end of the storage tube 1, thereby sealing the storage tube 1;

[0078] Gas is injected into the storage tube 1 through the air source, the air inlet pipe, the first female connector and the first male connector 31. Under the action of air pressure, the water in the storage tube 1 is discharged through the drainage component; after the water in the storage tube 1 is discharged, the first female connector is pulled by the first remote separation component to separate the first female connector and the first male connector 31, and the first male connector 31 is in a sealed state.

[0079] like Figure 1 As shown, in an optional embodiment of the present invention, the drainage assembly includes:

[0080] A second male connector 41, which is connected to the drainage hole 23 on the surface of the sealing cover 2;

[0081] A liquid guide tube 42, wherein a first end of the liquid guide tube 42 is connected to the drainage hole 23, and a second end of the liquid guide tube 42 extends to the inner bottom surface of the storage tube 1;

[0082] A second female connector that plugs and mates with the second male connector 41;

[0083] A drainage pipe, the water inlet end of the drainage pipe is connected to the second female connector;

[0084] A second remote disconnect assembly is coupled to the second female connector.

[0085] In this embodiment, the second male connector 41 and the second female connector are respectively the male connector and the female connector of the quick connector. The second male connector 41 is in a sealed state under normal conditions. After the second female connector is plugged into the second male connector 41, the second female connector and the second male connector 41 are connected.

[0086] The second male connector 41 is connected to the drain hole 23, and the liquid guide tube 42 is connected to the drain hole 23. After the sealing cover 2 is removed from the pool using salvaging equipment, the second female connector is plugged into the second male connector 41 to connect the drain pipe to the second male connector 41. The second remote separation assembly is connected to the second female connector.

[0087] After all the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly are stored in the storage tube 1, the sealing cover 2 is placed on the upper end of the storage tube 1 using salvage equipment, and multiple connecting bolts 5 are screwed through the remote disassembly assembly to connect the sealing cover 2 to the upper end of the storage tube 1, thereby sealing the storage tube 1;

[0088] Air is injected into the storage tube 1 through the inflation component. Under the action of air pressure, the water in the storage tube 1 is discharged through the liquid guide tube 42, the second male connector 41, the second female connector and the drain pipe. After the water in the storage tube 1 is discharged, the second female connector is pulled by the second remote separation component to separate the second female connector from the second male connector 41, and the second male connector 41 is in a sealed state.

[0089] like Figure 5 and Figure 6 As shown, in an optional embodiment of the present invention, the first remote separation component and the second remote separation component both include:

[0090] A connecting ring 81, the inner diameter of which matches the outer diameters of the first female connector and the second female connector;

[0091] A first ear plate 84 and a second ear plate 85 are formed at both ends of the opening of the connecting ring 81, and the first ear plate 84 and the second ear plate 85 are connected by a fastening bolt 86 and a fastening nut 87;

[0092] A portal frame 82 connected to the connecting ring 81;

[0093] A lifting ring 83 connected to the portal frame 82;

[0094] A rope connected to the eye 83.

[0095] In this embodiment, the first female connector or the second female connector is passed through the connecting ring 81, and the air intake pipe or the drain pipe is passed through the door frame 82. The fastening bolts 86 are passed through the first ear plate 84 and the second ear plate 85. The fastening nuts 87 are screwed onto the ends of the fastening bolts 86 to clamp the connecting ring 81 to the outside of the first female connector or the second female connector. The rope is connected to the lifting ring 83.

[0096] After the water in the storage pipe 1 is drained, the lifting ring 83 is pulled by the rope, and the connecting ring 81 is pulled by the door frame 82, so that the connecting ring 81 drives the first female connector to separate from the first male connector 31, or the second female connector to separate from the second male connector 41;

[0097] In this embodiment, the lifting ring 83 is located in the middle of the portal frame 82. By pulling the connecting ring 81 through the lifting ring 83 and the portal frame 82, the connecting ring 81 can be evenly stressed, so that the first female connector or the second female connector is evenly stressed, which facilitates the separation of the first female connector and the first male connector 31, or the separation of the second female connector and the second male connector 41.

[0098] like Figure 1 and Figure 2 As shown, in an optional embodiment of the present invention, the underwater storage device for damaged pipe sections of spent fuel assemblies further includes:

[0099] A connecting plate 11 is formed on the edge of the upper end of the storage tube 1. A plurality of threaded holes 12 are formed through the surface of the connecting plate 11. The plurality of threaded holes 12 are evenly distributed around the circumference of the storage tube 1. The plurality of threaded holes 12 are adapted to the plurality of connecting bolts 5.

[0100] A plurality of connecting through holes 24 are provided through the surface of the sealing cover 2 . The plurality of connecting through holes 24 correspond to the plurality of threaded holes 12 . The plurality of connecting bolts 5 are located in the plurality of connecting through holes 24 .

[0101] In this embodiment, the sealing cover 2 and the connecting plate 11 are connected by a plurality of connecting bolts 5, which can ensure the stability of the connection between the sealing cover 2 and the upper end of the storage tube 1;

[0102] The number of connecting through holes 24 is an even number, and each connecting through hole 24 has a connecting through hole 24 symmetrically distributed with respect to the axis of the storage tube 1. This arrangement enables the connection force between the sealing cover 2 and the connecting plate 11 to be symmetrical and uniform, further ensuring the stability of the connection between the sealing cover 2 and the upper end of the storage tube 1.

[0103] In this embodiment, the depth of the connecting through hole 24 is greater than half the length of the threaded section of the connecting bolt 5. In this way, when the connecting bolt 5 is disassembled, after the connecting bolt 5 is completely separated from the threaded hole 12, the connecting thread can be stably located inside the connecting through hole 24. When the sealing cover 2 is clamped and moved by the salvage equipment, the connecting bolt 5 can be prevented from being separated from the connecting through hole 24.

[0104] In an optional embodiment of the present invention, the underwater storage device for damaged pipe sections of spent fuel assemblies further comprises:

[0105] An annular groove 13 is formed on the surface of the connecting plate 11 and is distributed on the outer side of the upper end of the storage tube 1;

[0106] The sealing ring 14 is embedded in the annular groove 13 , and a portion of the sealing ring 14 protrudes from the upper surface of the connecting disk 11 .

[0107] In this embodiment, by providing the sealing ring 14, after the connection between the sealing cover 2 and the connecting plate 11 is completed, the sealing ring 14 is fully in contact with the sealing cover 2, thereby ensuring the sealing of the connection between the sealing cover 2 and the connecting plate 11, thereby ensuring the sealing of the storage tube 1, and ensuring the storage safety of the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly.

[0108] like Figure 1 and Figure 2 As shown, in an optional embodiment of the present invention, the underwater storage device for damaged pipe sections of spent fuel assemblies further includes:

[0109] A clamping end 21 connected to the sealing cover 2.

[0110] In this embodiment, the clamping end 21 is adapted to the clamping end of the salvaging equipment, so that the clamping end 21 is clamped by the clamping end of the salvaging equipment, thereby clamping and removing the sealing cover 2 and placing the sealing cover 2 on the upper end port of the storage tube 1.

[0111] like Figure 2 As shown, in an optional embodiment of the present invention, the underwater storage device for damaged pipe sections of spent fuel assemblies further includes:

[0112] A one-way exhaust valve 6 is connected to the upper surface of the sealing cover 2 , and an air inlet end of the one-way exhaust valve 6 is communicated with the storage tube 1 .

[0113] In this embodiment, when the storage tube 1 is used to store fragments of partially damaged and disintegrated nuclear fuel assemblies and scattered shells, fuel pipe sections, etc. of spent fuel assemblies, the temperature inside the storage tube 1 will increase, causing the pressure inside the storage tube 1 to increase. By providing a one-way exhaust valve 6, the pressure inside the storage tube 1 can be released, ensuring the safety of the storage tube 1, thereby ensuring the safe storage of fragments of partially damaged and disintegrated nuclear fuel assemblies and scattered shells, fuel pipe sections, etc. of spent fuel assemblies, and preventing radioactive leakage.

[0114] like Figure 1 As shown, in an optional embodiment of the present invention, the underwater storage device for damaged pipe sections of spent fuel assemblies further includes:

[0115] The reinforcing plate 15 connected to the bottom surface of the storage tube 1 abuts against the bottom surface of the storage cavity of the water tank storage grid 9.

[0116] In this embodiment, by providing a reinforcing plate 15 on the bottom surface of the storage tube 1, and the reinforcing plate 15 abutting against the bottom surface of the storage cavity of the water pool storage grid 9, the overall strength of the storage tube 1 can be increased. At the same time, when the storage tube 1 is placed in the storage cavity of the water pool storage grid, the storage tube 1 can be effectively supported, ensuring the safety and stability of the storage tube 1 in the storage cavity of the water pool storage grid, preventing deformation and damage of the storage tube 1, ensuring the safe storage of fragments such as the shells and fuel tube sections of partially damaged and disintegrated nuclear fuel assemblies and scattered spent fuel assemblies, and preventing radioactive leakage.

[0117] like Figure 4 As shown, in an optional embodiment of the present invention, the remote disassembly assembly includes:

[0118] A top threaded rod 71 , with an operating handle 74 connected to the top of the top threaded rod 71 ;

[0119] multiple mid-threaded rods;

[0120] bottom threaded rod 72;

[0121] The outer sides of the top threaded rod 71, the plurality of middle threaded rods and the bottom threaded rod 72 are all threadedly connected with a connecting sleeve 73;

[0122] The screwing block 75 is connected to the bottom end of the bottom threaded rod 72 . A contoured cavity 76 is formed on the bottom surface of the screwing block 75 . The contoured cavity 76 is adapted to the screwing end of the connecting bolt 5 .

[0123] In this embodiment, the connecting sleeve 73 can realize the butt connection between the top threaded rod 71 and the middle threaded rod, realize the butt connection between the two middle threaded rods, and realize the butt connection between the middle threaded rod and the bottom threaded rod 72. In actual use, by adjusting the number of middle threaded rods, the length of the remote disassembly assembly can be adjusted to meet different usage requirements.

[0124] When disassembling and installing multiple connecting bolts 5, the operator holds the operating handle 74, so that the contoured cavity 76 corresponds to the screwing end of the connecting bolt 5, and the screwing end of the connecting bolt 5 enters the contoured cavity 76. The operator rotates the top threaded rod 71 through the operating handle 74, so that the screwing block 75 drives the connecting bolt 5 to rotate, thereby realizing the disassembly or installation of the connecting bolt 5. The operator can complete the disassembly and installation of the connecting bolt 5 remotely, ensuring the safety of the operator.

[0125] Underwater storage method for damaged pipe sections of spent fuel assemblies:

[0126] Under normal conditions, the storage tube 1 is placed in the storage cavity of the water tank storage grid 9, and the sealing cover 2 is connected to the upper end of the storage tube 1 to seal the storage tube 1;

[0127] When there are fragments of partially damaged and disintegrated nuclear fuel assemblies and scattered shells, fuel pipe sections, etc. of spent fuel assemblies at the bottom of the storage pool, a corresponding number of middle threaded rods are selected according to the position of the storage tube 1, and the top threaded rod 71 and the middle threaded rod are butt-connected through the connecting sleeve 73, so that the two middle threaded rods are butt-connected, and the middle threaded rod and the bottom threaded rod 72 are butt-connected, thereby completing the assembly of the remote disassembly assembly; the operator holds the operating handle 74, so that the contoured cavity 76 corresponds to the screwing end of the connecting bolt 5, and the screwing end of the connecting bolt 5 enters the contoured cavity 76, and the operator rotates the top threaded rod 71 by the operating handle 74 so that the screwing block 75 drives the connecting bolt 5 to rotate to realize the disassembly of the connecting bolt 5; the sealing cover 2 is clamped and taken out by the salvaging equipment; the first female connector is passed through the connecting ring 81 of the first remote separation component, the fastening nut 87 of the first remote separation component is screwed, and the fastening bolt 86 is used to realize the connection between the connecting ring 81 of the first remote separation component and the first female connector, so that the first female connector is plug-connected with the first male connector 31 to complete the installation of the inflatable component; the second female connector is passed through the connecting ring 81 of the second remote separation component, the fastening nut 87 of the second remote separation component is screwed, and the fastening bolt 86 is used to realize the connection between the connecting ring 81 of the second remote separation component and the second female connector, so that the second female connector is plug-connected with the first male connector 31 to complete the installation of the inflatable component; The female connector is plugged into the second male connector 41 to complete the installation of the drainage assembly; the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly are clamped and salvaged by the salvaging equipment and placed in the storage tube 1. After the fragments of the partially damaged and disintegrated nuclear fuel assembly and the scattered shells, fuel pipe sections, etc. of the spent fuel assembly are all stored in the storage tube 1, the sealing cover 2 is placed on the upper end of the storage tube 1 by the salvaging equipment. The operator rotates the top threaded rod 71 by operating the handle 74, so that the screw block 75 drives the connecting bolt 5 to rotate, thereby realizing the installation of the connecting bolt 5, thereby realizing the connection between the sealing cover 2 and the upper end of the storage tube 1 and realizing the sealing of the storage tube 1; through the gas source, The air inlet pipe, the first female connector, and the first male connector 31 inject gas into the storage tube 1. Under the action of the gas pressure, the water in the storage tube 1 is discharged through the liquid guide tube 42, the second male connector 41, the second female connector, and the drain pipe. After the water in the storage tube 1 is discharged, the ropes of the first remote separation assembly and the second remote separation assembly are pulled respectively. The ropes pull the lifting ring 83, and the connecting ring 81 is pulled through the portal 82. The connecting ring 81 drives the first female connector to separate from the first male connector 31, or the second female connector to separate from the second male connector 41. This completes the collection and storage of fragments such as the scattered casing and fuel pipe sections of the partially damaged and disintegrated nuclear fuel assembly and the spent fuel assembly, thereby preventing radioactive leakage.

[0128] Through the above process, the debris of the shell, fuel pipe section, etc. after the spent fuel assembly falls and disintegrates can be cleaned and stored to avoid radioactive leakage. All operations can be completed remotely to ensure the safety of the operators.

[0129] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An underwater storage device for damaged pipe sections of spent fuel assemblies, characterized in that: include: A storage tube (1) placed in a storage cavity of a water tank storage grid (9); A sealing cover (2), the sealing cover (2) being detachably connected to the upper end of the storage tube (1) via a plurality of connecting bolts (5); A remote disassembly and assembly component for disassembling and installing a plurality of connecting bolts (5); a detachable inflation component, the inflation component being arranged on the surface of the sealing cover (2), and the gas outlet end of the inflation component being connected to the storage tube (1); a detachable drainage assembly, the drainage assembly being arranged on the surface of the sealing cover (2), the water inlet end of the drainage assembly being in communication with the storage pipe (1); Wherein, the inflatable component includes: a first male connector (31), the first male connector (31) being connected to an air inlet (22) on a surface of the sealing cover (2), the air inlet (22) being in communication with the storage tube (1); a first female connector pluggably mated with the first male connector (31); an air inlet pipe, wherein the air inlet end of the air inlet pipe is connected to the air source, and the air outlet end of the air inlet pipe is connected to the first female connector; a first remote disconnect assembly connected to the first female connector; Wherein, the drainage component includes: a second male connector (41), the second male connector (41) being connected to a drainage hole (23) on the surface of the sealing cover (2); a liquid guide tube (42), wherein a first end of the liquid guide tube (42) is connected to the drainage hole (23), and a second end of the liquid guide tube (42) extends to the inner bottom surface of the storage tube (1); a second female connector pluggably mated with the second male connector (41); a drain pipe, wherein the water inlet end of the drain pipe is connected to the second female connector; A second remote disconnect assembly is connected to the second female connector.

2. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: The first remote separation assembly and the second remote separation assembly each include: a connecting ring (81), wherein the inner diameter of the connecting ring (81) is adapted to the outer diameters of the first female connector and the second female connector; A first ear plate (84) and a second ear plate (85) are respectively formed at both ends of the opening of the connecting ring (81), and the first ear plate (84) and the second ear plate (85) are connected by a fastening bolt (86) and a fastening nut (87); A portal frame (82) connected to the connecting ring (81); A lifting ring (83) connected to the portal frame (82); A rope connected to the lifting ring (83).

3. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: Also includes: A connecting plate (11) is formed on the edge of the upper end of the storage tube (1), and a plurality of threaded holes (12) are provided on the surface of the connecting plate (11). The plurality of threaded holes (12) are evenly distributed around the circumference of the storage tube (1) as a reference axis, and the plurality of threaded holes (12) are adapted to the plurality of connecting bolts (5); A plurality of connecting through holes (24) are provided through the surface of the sealing cover (2), the plurality of connecting through holes (24) correspond to the plurality of threaded holes (12), and the plurality of connecting bolts (5) are located in the plurality of connecting through holes (24).

4. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 3, characterized in that: Also includes: an annular groove (13) formed on the surface of the connecting plate (11), the annular groove (13) being distributed on the outer side of the upper end of the storage tube (1); A sealing ring (14), wherein the sealing ring (14) is embedded in the annular groove (13), and a portion of the sealing ring (14) protrudes from the upper surface of the connecting disk (11).

5. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: Also includes: A clamping end (21) connected to the sealing cover (2).

6. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: Also includes: A one-way exhaust valve (6) is connected to the upper surface of the sealing cover (2), and an air inlet end of the one-way exhaust valve (6) is connected to the storage tube (1).

7. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: Also includes: A reinforcing plate (15) connected to the bottom surface of the storage tube (1), wherein the reinforcing plate (15) abuts against the bottom surface of the storage cavity of the water tank storage grid (9).

8. The underwater storage device for damaged pipe sections of spent fuel assemblies according to claim 1, characterized in that: The remote disassembly and assembly component includes: A top threaded rod (71), wherein the top end of the top threaded rod (71) is connected to an operating handle (74); multiple mid-threaded rods; bottom threaded rod (72); The outer sides of the top threaded rod (71), the plurality of middle threaded rods and the bottom threaded rod (72) are all threadedly connected to a connecting sleeve (73); A screwing block (75) is connected to the bottom end of the bottom threaded rod (72), and a contoured cavity (76) is formed on the bottom surface of the screwing block (75), and the contoured cavity (76) is adapted to the screwing end of the connecting bolt (5).

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