Nuclear fuel storage tank welding seam removing device and method

Abstract

The invention belongs to the technical field of nuclear reactor engineering, and particularly relates to a nuclear fuel storage tank welding seam removing device and method.The nuclear fuel storage tank welding seam removing device comprises a rack, and a machine head lifting device is installed on the rack; the machine head lifting device drives the machine head assembly to move up and down. The end, away from the machine head lifting device, of the machine head assembly is connected with a positioning rod, and the machine head assembly drives the positioning rod to rotate. A positioning ring is arranged at the end, away from the machine head assembly, of the positioning rod. The positioning ring is matched with the center of the storage tank cover; the machine head lifting device descends to drive the positioning rod and the machine head assembly to penetrate through the hole so that the positioning ring can make contact with the storage tank cover. The positioning ring and the storage tank cover are matched for positioning, and the cutting tool bit rotates around the positioning rod to cut the storage tank opening, so that the seal welding seam of the nuclear fuel storage tank of the pebble-bed type high-temperature gas cooled reactor nuclear power station is removed.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear reactor engineering, and in particular relates to a device and method for removing welds from a nuclear fuel storage tank. Background Art

[0002] The pebble bed high temperature gas-cooled reactor nuclear power plant uses spherical fuel elements with a diameter of 6 cm. Tens of thousands of fuel elements are stored in tanks with a tank opening diameter of about 13 cm. The tank opening and the tank cover are sealed by welding to prevent radioactive substances from escaping during storage.

[0003] When the core needs to be reloaded, the nuclear fuel tank sealing weld seam removal device is needed to remove the tank sealing weld seam so as to pull out the tank cover and take out the fuel elements in the tank. Due to the limited space in the nuclear power plant building, the nuclear fuel tank sealing weld seam removal device needs to pass through the floor and narrow holes downward to reach the top of the nuclear fuel tank located in the shielding cover, and complete the weld removal at the tank mouth under the condition of being exposed to radiation from the tank.

[0004] In the prior art, a nuclear fuel tank sealing weld seam removal device is designed to achieve the cutting of spent fuel tanks. However, the cutting execution components of these devices cannot pass through narrow holes and are not suitable for removing the sealing weld seams of nuclear fuel tanks in pebble bed high temperature gas-cooled reactor nuclear power plants. Summary of the invention

[0005] In view of the above problems, the present invention proposes a nuclear fuel tank sealing welding weld removal device, comprising a frame, a machine head lifting device is installed on the frame; the machine head lifting device drives the machine head assembly to move up and down; the end of the machine head assembly away from the machine head lifting device is connected to a positioning rod, and the machine head assembly drives the positioning rod to rotate; a positioning ring is provided at one end of the positioning rod away from the machine head assembly; the positioning ring is adapted to the center of the tank cover;

[0006] The head lifting device descends to drive the positioning rod and the head assembly through the hole so that the positioning ring contacts the tank cover;

[0007] The machine head assembly includes a cutting head; the positioning rod is located at the central axis position of the machine head assembly, and the distance between the cutting head and the positioning rod is equal to the radius of the tank cover; the machine head assembly drives the cutting head to rotate while rotating around the positioning rod, and the cutting head cuts the weld between the tank cover and the tank mouth.

[0008] Furthermore, a position adjustment mechanism is installed between the head lifting device and the head assembly, the head lifting device drives the head assembly and the position adjustment mechanism to move up and down, and the position adjustment mechanism drives the head assembly to move in the horizontal direction; the head assembly also includes a rotating motor, a thrust electric cylinder and a cutting motor connected in sequence; the fixed end of the rotating motor is connected to the position adjustment mechanism, and the output end of the rotating motor is connected to the thrust electric cylinder; the cutting motor is installed inside the mounting shell, and the output end of the thrust electric cylinder is connected to the upper end of the mounting shell; the cutting head is connected to the output end of the cutting motor; one end of the positioning rod is connected to the outer shell of the thrust electric cylinder; a reducer is installed between the cutting motor and the cutting head.

[0009] Furthermore, the head lifting device includes a driving mechanism and a sprocket; the two groups of sprockets are respectively rotatably installed on two opposite inner walls of the frame, and a transmission mechanism is installed between the two groups of sprockets; the driving mechanism is installed on the frame, and the driving mechanism drives the transmission mechanism to rotate; the two output ends of the transmission mechanism are respectively connected to one of the two groups of sprockets; each group of sprockets is meshed with an annular chain; the annular chain is connected to the position adjustment mechanism; two groups of slide rail pairs are installed on the frame, and the two end surfaces of the position adjustment mechanism are respectively slidably connected to the two groups of slide rail pairs.

[0010] Furthermore, the position adjustment mechanism includes an outer shell; the two side surfaces of the outer shell are respectively fixedly connected to two sets of ring chains and slidably connected to two sets of slide rail pairs; a horizontal adjustment mechanism is provided on the outer shell; the fixed end of the rotating motor is installed on the horizontal adjustment mechanism, and the horizontal adjustment mechanism drives the rotating motor to move in the horizontal direction.

[0011] Furthermore, a spring assembly is installed between the horizontal adjustment mechanism and the rotating motor; the spring assembly includes a first disk and a second disk; the first disk is connected to the horizontal adjustment mechanism; the second disk is connected to the rotating motor, and multiple groups of spring bodies are evenly arranged between the first disk and the second disk.

[0012] Furthermore, the mounting end of the rotating motor is fixedly installed at the lower end of the No. 2 disk, and the output end of the rotating motor is connected to the inner part of the slewing bearing; the outer ring of the inner part of the slewing bearing is rotatably connected to the outer part of the slewing bearing; an outer cylinder No. 1 is connected between the outer part of the slewing bearing and the No. 2 disk, and the inner wall of the outer cylinder No. 1 is fixed to the outer shell of the rotating motor.

[0013] Furthermore, a bearing is sleeved inside the positioning ring, and the positioning ring is rotatably connected to the positioning rod through the bearing, and the positioning ring and the tank cover remain relatively stationary.

[0014] Furthermore, the driving mechanism is a manual operating mechanism and a lifting motor, and the manual operating mechanism and the lifting motor are connected to the transmission mechanism;

[0015] An inner slide rail is installed on the inner wall of the outer shell; an inner tray is slidably connected to the inner slide rail; the horizontal adjustment mechanism is installed on the inner tray; a driving assembly is installed on the outer shell; the driving assembly includes a driving motor and a transmission assembly; a lead screw is rotatably connected between the upper and lower ends of the inner wall of the outer shell, and the driving motor drives the lead screw to rotate through the transmission assembly; a ball nut is slidably connected to the lead screw, and the ball nut is fixedly connected to the inner tray.

[0016] Furthermore, it also includes a chip cleaning device, which is installed on the head assembly; the chip cleaning device includes an air supply nozzle and an exhaust nozzle, and one end of the air supply nozzle, the exhaust nozzle and the camera are fixed to the cutting motor housing; one end of the air supply nozzle and the exhaust nozzle is connected to the air pump, and the other end of the air supply nozzle, the exhaust nozzle and the camera is limited by the third disk; the second outer cylinder is connected between the third disk and the inner part of the rotary bearing.

[0017] The present invention provides a method for removing a weld seam of a nuclear fuel tank, using any one of the above-mentioned devices for removing a weld seam of a nuclear fuel tank, and specifically comprising the following steps:

[0018] Move the tank to the tank mouth cutting position by using the tank moving equipment;

[0019] Start the machine head lifting device, which drives the machine head assembly and the positioning rod to move downward, and the machine head and the positioning rod pass through the floor and the hole and descend to the tank cover;

[0020] Start the horizontal adjustment mechanism, which drives the machine head assembly and the positioning rod to move in the horizontal direction, so that the center of the positioning rod is aligned with the center of the tank cover;

[0021] The positioning rod is pressed down to the center of the tank cover, and the positioning rod serves as the rotation axis for the circumferential feeding of the cutting head;

[0022] Start the thrust electric cylinder to drive the cutting head to move slowly downward to achieve axial feeding;

[0023] The rotating motor and the cutting motor are started, the cutting motor drives the cutting head to rotate, and the rotating motor drives the cutting head to move circumferentially along the annular weld.

[0024] The beneficial effects of the present invention compared to the prior art are as follows:

[0025] (I) The present invention drives the machine head assembly and the positioning rod to descend through the floor and the hole through the machine head lifting device, and cooperates with the tank cover to position through the positioning ring, and cuts the tank mouth by rotating the cutting head around the positioning rod, thereby realizing the removal of the sealing welding weld of the nuclear fuel tank of the pebble bed high temperature gas-cooled reactor nuclear power plant.

[0026] (ii) The present invention limits the air supply nozzle, the exhaust nozzle and the camera by means of the No. 3 disk. When the air supply nozzle, the exhaust nozzle and the camera are driven by the rotating motor to rotate, the No. 3 disk and the No. 2 outer cylinder rotate together, thereby improving the stability of the relative position of the air supply nozzle, the exhaust nozzle and the camera with the cutting head during the rotation process.

[0027] (III) The present invention enables the air supply nozzle, the exhaust nozzle and the camera to move downward a short distance along with the cutting motor under the drive of the thrust electric cylinder, so that the air supply and exhaust directions are more accurate and the video observation is more precise.

[0028] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A schematic diagram of a three-dimensional structure in an embodiment of the present invention is shown.

[0031] Figure 2 A schematic diagram of the structure near the tank opening in an embodiment of the present invention is shown.

[0032] Figure 3 A structural schematic diagram showing the position of the head assembly in an embodiment of the present invention.

[0033] Figure 4 A structural schematic diagram showing the position of the drive assembly in an embodiment of the present invention.

[0034] In the figure, 1, tank cover; 2, tank opening; 3, weld; 4, inner slide rail; 5, inner tray; 10, frame; 20, head lifting device; 201, driving mechanism; 2011, manual operating mechanism; 2012, lifting motor; 202, sprocket; 203, transmission mechanism; 204, ring chain; 205, slide rail pair;

[0035] 30. Position adjustment mechanism; 301. Outer shell; 302. Level adjustment mechanism; 303. Spring assembly; 3031. Disc No. 1; 3032. Disc No. 2; 3033. Spring body;

[0036] 40. Head assembly; 401. Rotating motor; 402. Thrust electric cylinder; 403. Cutting motor; 404. Cutting head; 405. Mounting housing; 406. Rotary bearing inner part; 407. Rotary bearing outer part; 408. Speed ​​reducer;

[0037] 50, positioning rod; 60, positioning ring; 70, chip cleaning device; 701, air supply nozzle; 702, exhaust nozzle; 703, third plate; 80, camera;

[0038] 901, driving motor; 902, transmission assembly; 903, lead screw; 904, ball nut. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] At present, the opening of nuclear fuel storage tanks is sealed by welding. The weld is annular and has a diameter of about 13 cm. If the tank is to be reopened, the sealing weld of the tank opening needs to be cut to pull out the tank cover and take out the fuel elements in the tank.

[0041] The present application provides a nuclear fuel tank weld removal device, referring to Figure 1 , comprising a frame 10, on which a head lifting device 20 is installed; the head lifting device 20 drives a head assembly 40 to move up and down; the end of the head assembly 40 away from the head lifting device 20 is connected to a positioning rod 50, and the head assembly 40 drives the positioning rod 50 to rotate; a positioning ring 60 is provided at the end of the positioning rod 50 away from the head assembly 40; the positioning ring 60 is adapted to the center of the tank cover 1;

[0042] The head lifting device 20 descends to drive the positioning rod 50 and the head assembly 40 to pass through the hole so that the positioning ring 60 contacts the tank cover 1;

[0043] refer to Figure 2 The machine head assembly 40 includes a cutting head 404; the positioning rod 50 is located at the central axis position of the machine head assembly 40, and the distance between the cutting head 404 and the positioning rod 50 is equal to the radius of the tank cover 1; the machine head assembly 40 drives the cutting head 404 to rotate and rotate around the positioning rod 50 at the same time, and the cutting head 404 cuts the weld 3 between the tank cover 1 and the tank mouth 2.

[0044] refer to Figure 3A position adjustment mechanism 30 is installed between the head lifting device 20 and the head assembly 40. The head lifting device 20 drives the head assembly 40 and the position adjustment mechanism 30 to move up and down, and the position adjustment mechanism 30 drives the head assembly 40 to move in the horizontal direction; the head assembly 40 also includes a rotating motor 401, a thrust cylinder 402 and a cutting motor 403 connected in sequence; the fixed end of the rotating motor 401 is connected to the position adjustment mechanism 30, and the output end of the rotating motor 401 is connected to the thrust cylinder 402; the cutting motor 403 is installed inside the mounting shell 405, and the output end of the thrust cylinder 402 is connected to the upper end of the mounting shell 405; the cutting head 404 is connected to the output end of the cutting motor 403; one end of the positioning rod 50 is connected to the outer shell of the thrust cylinder 402; a reducer 408 is installed between the cutting motor 403 and the cutting head 404.

[0045] refer to Figure 1 The head lifting device 20 includes a driving mechanism 201 and a sprocket 202; the two groups of sprockets 202 are rotatably mounted on the two opposite inner walls of the frame 10, and a transmission mechanism 203 is installed between the two groups of sprockets 202; the driving mechanism 201 is installed on the frame 10, and the driving mechanism 201 drives the transmission mechanism 203 to rotate; the two output ends of the transmission mechanism 203 are respectively connected to one sprocket 202 in the two groups of sprockets 202; each group of sprockets 202 is meshed with an annular chain 204; the annular chain 204 is connected to the position adjustment mechanism 30; two groups of slide rail pairs 205 are installed on the frame 10, and the two end surfaces of the position adjustment mechanism 30 are respectively slidably connected to the two groups of slide rail pairs 205.

[0046] The driving mechanism 201 is a manual operating mechanism 2011 and a lifting motor 2012, and the manual operating mechanism 2011 and the lifting motor 2012 are connected to the transmission mechanism 203;

[0047] refer to Figure 4 An inner slide rail 4 is installed on the inner wall of the outer shell 301; an inner tray 5 is slidably connected to the inner slide rail; the horizontal adjustment mechanism 302 is installed on the inner tray 5; a driving assembly is installed on the outer shell 301; the driving assembly includes a driving motor 901 and a transmission assembly 902; a lead screw 903 is rotatably connected between the upper and lower ends of the inner wall of the outer shell 301, and the driving motor 901 drives the lead screw 903 to rotate through the transmission assembly 902; a ball nut 904 is slidably connected to the lead screw 903, and the ball nut 904 is fixedly connected to the inner tray 5.

[0048] The position adjustment mechanism 30 includes an outer shell 301; the two side surfaces of the outer shell 301 are respectively fixedly connected to two sets of ring chains 204 and slidably connected to two sets of slide rail pairs 205; a horizontal adjustment mechanism 302 is provided on the outer shell 301; the fixed end of the rotating motor 401 is installed on the horizontal adjustment mechanism 302, and the horizontal adjustment mechanism 302 drives the rotating motor 401 to move in the horizontal direction.

[0049] A bearing is sleeved inside the positioning ring 60 , and the positioning ring 60 is rotatably connected to the positioning rod 50 via the bearing, and the positioning ring 60 and the tank cover 1 remain relatively stationary.

[0050] During the implementation process, the tank moving device is first started to move the tank to the tank mouth cutting position, at which time the tank mouth is in a sealed welding state; then the machine head lifting device 20 is started, and the lifting motor 2012 drives the two sprockets 202 to rotate through the transmission mechanism 203, and the two sprockets 202 drive the annular chain 204 to rotate on the two sets of sprockets 202; the annular chain 204 drives the outer shell 301 to move downward, and the outer shell 301 moves downward along the slide rail pair 205 at the same time; the outer shell 301 drives the positioning rod 50 to move downward, and the machine head assembly 40 and the positioning rod 50 pass through the floor and the hole The hole is lowered to the tank cover 1. The tank cover 1 is provided with a hole groove matching the positioning ring 60. The positioning ring 60 is inserted into the hole groove on the tank cover 1. The positioning ring 60 is reliably in contact with the tank cover 1. The positioning ring 60 is located at the center of the head assembly 40, and the head lifting device 20 is shut down; wherein the outer shell 301 and the head lifting device 20 are detachably connected. If the head assembly 40 fails, the head lifting device 20 can be lifted by the manual operating mechanism 2011, and then the head lifting device 20 can be separated from the head assembly 40, and the head assembly 40 can be repaired separately.

[0051] After the head assembly 40 is roughly lifted and lowered and positioned by the sprocket 202 and the ring chain 204, the drive motor 901 drives the screw 903 to rotate through the transmission assembly 902, and the screw 903 drives the ball nut 904 to move up and down, thereby driving the inner tray 5 to move accurately up and down along the four inner slide rails 4; thereby achieving precise lifting and lowering drive and positioning, and at the same time having a self-locking effect to prevent the head assembly 40 from falling.

[0052] If the deviation between the moving position of the storage tank and the cutting position of the tank mouth is large, the horizontal adjustment mechanism 302 drives the head assembly 40 to move in the X and Y directions to further compensate for the horizontal displacement, so that the center of the head assembly 40 is aligned with the center of the storage tank cover 1; the horizontal adjustment mechanism 302 drives the positioning rod 50 to move horizontally on the linear slide rail by a linear motor or manual adjustment to achieve compensation for horizontal displacement, and has a set of linear motors and linear slide rails in the X and Y directions respectively;

[0053] Then, the cutting motor 403 is started, and the cutting motor 403 drives the cutting head 404 to rotate. The cutting head 404 is located at the position of the weld 3 between the tank cover 1 and the tank, and the rotating motor 401 is started at the same time. The positioning ring 60 is located at the center position of the rotating motor 401. During the rotation of the rotating motor 401, the positioning rod 50 is used as the central axis. The positioning ring 60 remains relatively still with the tank cover 1 through friction. The inner ring of the bearing in the positioning ring 60 is connected to the positioning rod 50 and rotates under the drive of the rotating motor 401; the cutting head 404 rotates around the positioning rod 50, and the rotating motor 401 provides the cutting head 404 with power for axial feeding along the annular weld 3; the rotating motor 401 drives the cutting head 404 to rotate to cut the annular weld 3; the thrust electric cylinder 402 drives the cutting motor 403 and the cutting head 404 to move downward a small distance to achieve axial feeding and expand the cutting depth of the weld 3;

[0054] After the welding seam 3 is cut, the rotating motor 401, the cutting motor 403 and the thrust cylinder 402 are stopped, and the machine head lifting device 20 is started. The lifting motor 2012 drives the machine head assembly 40 and the positioning rod 50 to move upward, and the positioning ring 60 is separated from the hole groove in the center of the tank cover 1, and the machine head assembly 40 is lifted to the upper stop position without affecting the movement of the tank;

[0055] After the above steps, the sealing weld 3 of one spent fuel storage tank port 2 is removed; by repeating the above steps, the sealing welds 3 of multiple storage tank ports 2 can be removed;

[0056] The transmission mechanism 203 also has a self-locking function, so that the head lifting device 20 can self-lock through the transmission mechanism 203 to prevent the head assembly 40 from accidentally falling; when the head lifting assembly fails and cannot be automatically lifted, the manual operating mechanism 2011 is used for personnel at a distance away from the head assembly 40 to operate the drive transmission mechanism 203 to drive the sprocket 202 to rotate, thereby driving the head assembly 40 and the positioning rod 50 to move upward and away from the storage tank, so as to facilitate the maintenance of the head lifting device 20 after the storage tank is removed.

[0057] In the present application, the machine head lifting device 20 drives the machine head assembly 40 and the positioning rod 50 to descend through the floor and the hole, and cooperates with the tank cover 1 for positioning through the positioning ring 60, and the cutting head 404 rotates around the positioning rod 50 to cut the tank mouth 2, thereby achieving the removal of the sealing welding weld 3 of the nuclear fuel tank of the pebble bed type high temperature gas-cooled reactor nuclear power plant.

[0058] The present application has a compact structure, and the head assembly 40 can pass through a narrow hole with a diameter not exceeding 25 cm and a depth not exceeding 2 m, and withstand the local irradiation of 20 Gy / h at the tank mouth 2, so as to realize automatic cutting and removal of the sealing welding weld 3, and clean up the cuttings;

[0059] In one embodiment of the present invention, reference Figure 3 A spring assembly 303 is installed between the horizontal adjustment mechanism 302 and the rotating motor 401; the spring assembly 303 includes a No. 1 disk 3031 and a No. 2 disk 3032; the No. 1 disk 3031 is connected to the horizontal adjustment mechanism 302; the No. 2 disk 3032 is connected to the rotating motor 401, and a plurality of groups of spring bodies 3033 are evenly arranged between the No. 1 disk 3031 and the No. 2 disk 3032.

[0060] The setting of the spring body 3033 enables the positioning rod 50 to have a vertical buffering function to adapt to the dimensional error in the vertical direction caused by various factors, thereby ensuring the cutting position accuracy of the storage tank mouth 2;

[0061] In one embodiment of the present invention, the mounting end of the rotating motor 401 is fixedly mounted at the lower end of the No. 2 disk 3032, and the output end of the rotating motor 401 is connected to a slewing bearing inner part 406; the outer ring of the slewing bearing inner part 406 is rotatably connected to a slewing bearing outer part 407; an outer cylinder No. 1 is connected between the slewing bearing outer part 407 and the No. 2 disk 3032, and the inner wall of the outer cylinder No. 1 is fixed to the outer shell of the rotating motor 401.

[0062] In one embodiment of the present invention, it also includes a chip cleaning device 70, which is installed on the head assembly 40; the chip cleaning device 70 includes an air supply nozzle 701 and an exhaust nozzle 702, and the air supply nozzle 701 and the exhaust nozzle 702 are fixed to the outer shell of the cutting motor 403; one end of the air supply nozzle 701 is connected to the air pump, and one end of the exhaust nozzle 702 is connected to the atmosphere, and the other ends of the air supply nozzle 701 and the exhaust nozzle 702 are limited by the third disk 703, and the lower end of the third disk 703 is installed with a camera 80; a second outer cylinder is connected between the third disk 703 and the rotary bearing inner part 406.

[0063] During the implementation process, while the rotating motor 401 drives the thrust cylinder 402 to rotate, the No. 1 outer cylinder and the rotary bearing outer part 407 do not rotate with the rotating motor 401, and the rotating motor 401 also drives the rotary bearing inner part 406 to rotate. The rotary bearing inner part 406 drives the No. 2 outer cylinder (not shown in the figure) and the No. 3 disk 703 to rotate synchronously. Holes are opened on the No. 3 disk 703 to limit the air supply nozzle 701, the exhaust nozzle 702 and the camera 80. When the No. 3 disk 703 rotates with the rotating motor 401, the rotating motor 401 drives the cutting head 404 to rotate, and the No. 3 disk 703 rotates. The disk 703 drives the air supply nozzle 701 (the nozzle part in the figure is flat and thin, which can blow air more concentratedly on the cutting part), the exhaust nozzle 702 (the nozzle part in the figure is round and thick, which can better discharge the debris) and the camera 80 to rotate synchronously; the air supply nozzle 701 and the exhaust nozzle 702 collect and process the debris after cutting the tank mouth 2 area, and the camera 80 checks the cut weld 3 during the rotation process. The camera 80 is connected to the data acquisition storage system and the monitoring control system to store the collected data and adjust and control according to the monitoring data during the cutting process;

[0064] When the thrust cylinder drives the cutting head 404 to move downward a short distance, the air supply nozzle 701 and the camera 80 move downward a short distance together with the cutting motor 403, so that the air supply position of the air supply nozzle 701 can be more accurate for the cutting part, and the observation of the camera 80 can also be more accurate;

[0065] The air pump is installed around the weld 3 removal device. The gas from the air pump is filtered by a high-efficiency filter and then blown out from the air supply nozzle 701, forming a chip-clearing airflow for the weld 3. The air pump then drives the exhaust nozzle 702 to entrain the smoke and debris in the cutting area, which is then discharged from the exhaust nozzle 702 and then discharged through a high-efficiency filter.

[0066] The present application also proposes a method for removing a weld seam of a nuclear fuel tank, using any of the above-mentioned devices for removing a sealed weld seam 3 of a nuclear fuel tank, specifically comprising the following steps:

[0067] Move the tank to the tank mouth cutting position by using the tank moving equipment;

[0068] The machine head lifting device 20 is started, and the machine head lifting device 20 drives the machine head assembly 40 and the positioning rod 50 to move downward, and the machine head and the positioning rod 50 pass through the floor and the hole and descend to the storage tank cover 1;

[0069] The horizontal adjustment mechanism 302 is started, and the horizontal adjustment mechanism 302 drives the head assembly 40 and the positioning rod 50 to move in the horizontal direction, so that the center of the positioning rod 50 is aligned with the center of the tank cover 1;

[0070] The positioning rod 50 is pressed down to the center of the tank cover 1, and the positioning rod 50 serves as a rotation axis for the circumferential feeding of the cutting head 404;

[0071] Start the thrust electric cylinder 402 to drive the cutting head 404 to move slowly downward to achieve axial feeding;

[0072] The rotating motor 401 and the cutting motor 403 are started, the cutting motor 403 drives the cutting head 404 to rotate, and the rotating motor 401 drives the cutting head 404 to move circumferentially along the annular weld 3 .

[0073] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nuclear fuel tank weld removal device, characterized in that: The machine frame (10) comprises a machine head lifting device (20) mounted on the machine frame (10); the machine head lifting device (20) drives the machine head assembly (40) to move up and down; the end of the machine head assembly (40) away from the machine head lifting device (20) is connected to a positioning rod (50), and the machine head assembly (40) drives the positioning rod (50) to rotate; the end of the positioning rod (50) away from the machine head assembly (40) is provided with a positioning ring (60); the positioning ring (60) is adapted to the center of the storage tank cover (1); The head lifting device (20) descends to drive the positioning rod (50) and the head assembly (40) to pass through the hole so that the positioning ring (60) contacts the tank cover (1); The machine head assembly (40) comprises a cutting head (404); the positioning rod (50) is located at the central axis position of the machine head assembly (40), and the distance between the cutting head (404) and the positioning rod (50) is equal to the radius of the storage tank cover (1); the machine head assembly (40) drives the cutting head (404) to rotate on its own and rotate around the positioning rod (50) at the same time, and the cutting head (404) cuts the weld (3) between the storage tank cover (1) and the storage tank mouth (2).

2. A nuclear fuel tank weld removal device according to claim 1, characterized in that: A position adjustment mechanism (30) is installed between the machine head lifting device (20) and the machine head assembly (40); the machine head lifting device (20) drives the machine head assembly (40) and the position adjustment mechanism (30) to move up and down, and the position adjustment mechanism (30) drives the machine head assembly (40) to move in the horizontal direction; the machine head assembly (40) also includes a rotating motor (401), a thrust cylinder (402) and a cutting motor (403) connected in sequence; the fixed end of the rotating motor (401) is connected to the position adjustment mechanism (30) ) is connected, the output end of the rotating motor (401) is connected to the thrust electric cylinder (402); the cutting motor (403) is installed inside the mounting shell (405), and the output end of the thrust electric cylinder (402) is connected to the upper end of the mounting shell (405); the cutting head (404) is connected to the output end of the cutting motor (403); one end of the positioning rod (50) is connected to the outer shell of the thrust electric cylinder (402); a reducer (408) is installed between the cutting motor (403) and the cutting head (404).

3. A nuclear fuel tank weld removal device according to claim 2, characterized in that: The machine head lifting device (20) comprises a driving mechanism (201) and a sprocket (202); two groups of the sprockets (202) are rotatably mounted on two opposite inner walls of the frame (10), and a transmission mechanism (203) is mounted between the two groups of sprockets (202); the driving mechanism (201) is mounted on the frame (10), and the driving mechanism (201) drives the transmission mechanism (203) to rotate; two output ends of the transmission mechanism (203) are respectively connected to one sprocket (202) in the two groups of sprockets (202); an annular chain (204) is meshed on each group of the sprockets (202); the annular chain (204) is connected to the position adjustment mechanism (30); two groups of slide rail pairs (205) are mounted on the frame (10), and both end surfaces of the position adjustment mechanism (30) are respectively slidably connected to the two groups of slide rail pairs (205).

4. A nuclear fuel tank weld removal device according to claim 3, characterized in that: The position adjustment mechanism (30) comprises an outer shell (301); the two side surfaces of the outer shell (301) are respectively fixedly connected to two groups of ring chains (204) and slidably connected to two groups of slide rail pairs (205); a horizontal adjustment mechanism (302) is provided on the outer shell (301); the fixed end of the rotating motor (401) is installed on the horizontal adjustment mechanism (302), and the horizontal adjustment mechanism (302) drives the rotating motor (401) to move in a horizontal direction.

5. A nuclear fuel tank weld removal device according to claim 4, characterized in that: A spring assembly (303) is installed between the horizontal adjustment mechanism (302) and the rotating motor (401); the spring assembly (303) comprises a first disk (3031) and a second disk (3032); the first disk (3031) is connected to the horizontal adjustment mechanism (302); the second disk (3032) is connected to the rotating motor (401), and a plurality of groups of spring bodies (3033) are evenly arranged between the first disk (3031) and the second disk (3032).

6. A nuclear fuel tank weld removal device according to claim 3, characterized in that: The mounting end of the rotating motor (401) is fixedly mounted on the lower end of the second disk (3032), and the output end of the rotating motor (401) is connected to a slewing bearing inner part (406); the outer ring of the slewing bearing inner part (406) is rotatably connected to a slewing bearing outer part (407); an outer cylinder No. 1 is connected between the slewing bearing outer part (407) and the second disk (3032), and the inner wall of the outer cylinder No. 1 is fixed to the outer shell of the rotating motor (401).

7. A nuclear fuel tank weld removal device according to claim 4, characterized in that: A bearing is sleeved inside the positioning ring (60), and the positioning ring (60) is rotatably connected to the positioning rod (50) via the bearing, and the positioning ring (60) and the storage tank cover (1) remain relatively stationary.

8. A nuclear fuel tank weld removal device according to claim 7, characterized in that: The driving mechanism (201) is a manual operating mechanism (2011) and a lifting motor (2012), and the manual operating mechanism (2011) and the lifting motor (2012) are connected to the transmission mechanism (203); An inner slide rail (4) is installed on the inner wall of the outer shell (301); an inner tray (5) is slidably connected to the inner slide rail; the horizontal adjustment mechanism (302) is installed on the inner tray (5); a driving assembly is installed on the outer shell (301); the driving assembly includes a driving motor (901) and a transmission assembly (902); a lead screw (903) is rotatably connected between the upper and lower ends of the inner wall of the outer shell (301), and the driving motor (901) drives the lead screw (903) to rotate through the transmission assembly (902); a ball nut (904) is slidably connected to the lead screw (903), and the ball nut (904) is fixedly connected to the inner tray (5).

9. A nuclear fuel tank weld removal device according to claim 8, characterized in that: It also includes a chip cleaning device (70), which is installed on the head assembly (40); the chip cleaning device (70) includes an air supply nozzle (701) and an exhaust nozzle (702), and one end of the air supply nozzle (701), the exhaust nozzle (702) and the camera (80) are fixed to the outer shell of the cutting motor (403); one end of the air supply nozzle (701) and the exhaust nozzle (702) are connected to the air pump, and the other end of the air supply nozzle (701), the exhaust nozzle (702) and the camera (80) are limited by the third disk (703); a second outer cylinder is connected between the third disk (703) and the rotary bearing inner part (406).

10. A method for removing weld seams from a nuclear fuel tank, using a device for removing weld seams from a nuclear fuel tank as claimed in any one of claims 1 to 9, characterized in that: The specific steps include: Move the tank to the tank mouth cutting position by using the tank moving equipment; The machine head lifting device (20) is started, and the machine head lifting device (20) drives the machine head assembly (40) and the positioning rod (50) to move downward, and the machine head and the positioning rod (50) pass through the floor and the hole and descend to the storage tank cover (1); The horizontal adjustment mechanism (302) is started, and the horizontal adjustment mechanism (302) drives the head assembly (40) and the positioning rod (50) to move in the horizontal direction, so that the center of the positioning rod (50) is aligned with the center of the storage tank cover (1); The positioning rod (50) is pressed down to the center of the tank cover (1), and the positioning rod (50) serves as a rotation axis for the circumferential feeding of the cutting blade (404); Starting the thrust electric cylinder (402) to drive the cutting head (404) to move slowly downward to achieve axial feeding; The rotating motor (401) and the cutting motor (403) are started, the cutting motor (403) drives the cutting head (404) to rotate, and the rotating motor (401) drives the cutting head (404) to move circumferentially along the annular weld (3).

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