A fuel rod double-ended welding device

Abstract

This invention provides a double-ended welding device for fuel rods, comprising: a welding worktable, on which a mandrel position adjustment mechanism and a welding chamber are provided; the mandrel position adjustment mechanism has an end plug mandrel, a lead screw, and a tail adjustment motor; the tail adjustment motor drives the end plug mandrel to move forward and backward toward the welding chamber via the lead screw; a welding torch is provided inside the welding chamber; and a rotatable material rack for steering fuel rods and feeding and retracting them toward the welding chamber; the rotatable material rack has a lifting beam, a lifting arm, a lifting receiving trough, and a material rack lifting and rotating mechanism; the lifting arm is connected to the lifting beam, the lifting receiving trough is installed on the lifting arm, and the material rack lifting and rotating mechanism is located below the lifting beam; the connecting plate of the material rack lifting and rotating mechanism is driven by a motor to lift and rotate. This invention saves on-site space, improves equipment compatibility, and avoids the costs and site expenses of repeatedly purchasing equipment or the time wasted due to changing tooling.

Description

Technical Field

[0001] This invention relates to the field of nuclear fuel manufacturing technology, and in particular to a double-ended welding apparatus for fuel rods. Background Technology

[0002] Current fuel rod welding processes typically involve first welding the end plug to one side of the cladding tube, and then using a separate welding machine to weld the end plug to the other side of the cladding tube. Therefore, two machines are required to complete the fuel rod welding. However, using two machines for fuel rod welding increases equipment costs and space requirements, and also disrupts production, impacting efficiency. Summary of the Invention

[0003] The purpose of this invention is to overcome the defects described in the prior art, thereby providing a fuel rod double-head welding device that solves the problems of having to use two welding machines to weld the same fuel rod or the impact of machine downtime for tooling replacement on welding efficiency and welding atmosphere stability.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A fuel rod double-ended welding apparatus, comprising:

[0006] A welding workbench is provided with a mandrel position adjustment mechanism and a welding chamber. The mandrel position adjustment mechanism has an end plug mandrel, a lead screw and a tail adjustment motor. The tail adjustment motor drives the end plug mandrel to move forward and backward toward the welding chamber through the lead screw. A welding torch is provided in the welding chamber.

[0007] A rotatable feed rack is used to steer fuel rods and feed and retract them into the welding chamber. The rotatable feed rack has a lifting beam, a lifting arm, a lifting receiving trough, and a feed rack lifting and rotating mechanism. The lifting arm is connected to the lifting beam, the lifting receiving trough is installed on the lifting arm, and the feed rack lifting and rotating mechanism is located below the lifting beam. The connecting plate of the feed rack lifting and rotating mechanism is driven by a motor to lift and rotate.

[0008] As one feasible embodiment, the top position adjustment mechanism further comprises a tail adjustment center shaft, an adjustment bracket, a connecting base plate, a lead screw support, a guide rail, a guide rail slider, a transition base plate, and a coupling. One end of the tail adjustment center shaft is connected to the end plug top, and the other end is connected to the adjustment bracket. The adjustment bracket is connected to the connecting base plate. The lower part of the connecting base plate is connected to the guide rail slider and the lead screw nut by screws. The lead screw support and the guide rail are mounted on the transition base plate. The lead screw is connected to the output shaft of the tail adjustment motor through the coupling.

[0009] As one possible implementation, a pad is provided below the transition base plate.

[0010] As one possible implementation, the tail-end adjusting motor is mounted on a motor mounting plate such that the output shaft of the tail-end adjusting motor is at the same height as the lead screw.

[0011] As one possible implementation, the tail adjustment center shaft is provided with carbon brushes.

[0012] As one possible implementation, a timing pulley is provided on the tail adjustment center shaft.

[0013] As one feasible embodiment, the rotatable material rack further comprises a discharge guide plate, a V-groove with a plunger, a feeding paddle, a feeding cylinder, a movable beam on the feeding side, a movable beam on the discharging side, a movable beam slide rail, and a V-groove support frame. In the middle rotating portion of the rotatable material rack, the V-groove with a plunger is mounted on the movable beam on the discharging side via the V-groove support frame, and the feeding paddle and the feeding cylinder are mounted on the movable beam on the feeding side. In the fixed portions at both ends of the rotatable material rack, the discharge guide plate, the V-groove with a plunger, the feeding paddle, and the feeding cylinder are... The cylinder is connected to the fixed frame of the material rack. Before the lifting beam is raised and lowered, the movable beams on the upper and lower sides open to both sides along the movable beam slide rail. The lifting beam drives the lifting arm to rise, and at the same time, the lifting receiving groove lifts the fuel rod on the lowering slide rail. After it is raised to the position, the lifting beam rotates as a whole. Then the lifting beam falls, and the fuel rod is turned around and placed on the upper slide rail. The servo feeding mechanism is installed on the fixed frame at one end of the rotatable material rack and is aligned with the welding chamber inlet to feed a single fuel rod into or out of the welding chamber.

[0014] As one feasible approach, the material rack lifting and rotating mechanism also includes a lifting servo motor, a screw jack, a rotating servo motor, and a synchronous wheel. The lifting servo motor drives the screw jack to rotate the vertical lead screw, thereby lifting and lowering the connecting plate. After the lifting and lowering mechanism reaches its position, the rotating servo motor drives the connecting plate to rotate via the synchronous wheel.

[0015] As one possible implementation, the material rack lifting and rotating mechanism also has an idler wheel for tensioning the timing belt.

[0016] As one feasible approach, a front barcode reader and a rear barcode reader are also included, which are fixed at both ends of the rotatable material rack via connectors to read the barcodes of the fuel rods in the V-groove with plungers.

[0017] Compared with the prior art, the fuel rod double-ended welding device provided by the present invention has the following advantages:

[0018] The device of the present invention saves on-site space and improves equipment compatibility; it avoids the cost and site expenses of repeatedly purchasing equipment or the time consumption caused by changing tooling.

[0019] Furthermore, the apparatus of the present invention ensures continuous production through a reasonable arrangement of process sequences.

[0020] Furthermore, the device of the present invention, by setting up dual barcode readers, ensures that barcode information can be collected and recorded and the current welding position can be automatically determined before and after the shell is flipped, thus ensuring the accuracy of the welding parameter recording.

[0021] Furthermore, the device of the present invention uses a servo mechanism to position the end plug and the tube feed, which helps to improve the welding positioning control accuracy and automation level.

[0022] Furthermore, the device of the present invention can realize automatic batch flipping of fuel rods, reducing intermediate transfer steps and manual intervention. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of the fuel rod double-ended welding device provided in an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the top position adjustment mechanism provided in an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the end plug head provided in an embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the welding chamber observation system provided in an embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the structure of the rotatable material rack provided in an embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the structure of the material rack lifting and rotating mechanism provided in an embodiment of the present invention;

[0030] Figure 7 This is a schematic diagram of the arrangement of a dual barcode reader provided in an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1-Top position adjustment mechanism; 2-Welding worktable; 3-Welding chamber; 4-Rotating material rack; 5-End plug; 6-End plug top; 7-Pipe clamp; 8-Welding torch; 9-Tail adjustment center shaft; 10-Adjustment bracket; 11-Connecting base plate; 12-Lead screw; 13-Lead screw support seat; 14-Guide rail; 15-Guide rail slider; 16-Transition base plate; 17-Padded block; 18-Tail adjustment motor; 19-Coupling; 20-Motor mounting plate; 21-Synchronous pulley; 22-Carbon brush; 23-Front camera; 24-Rear light source; 25-Discharge guide plate; 26-V-groove with plunger; 27-Feeding paddle; 28-Feeding cylinder; 29-Feeding slide; 30-Discharging slide; 31-Lifting beam; 32-Modible beam on the feeding side; 33-Modible beam on the discharging side; 34-Modifying beam slide rail; 35-V-groove support frame; 36-Lifting arm; 37-Lifting receiving trough; 38-Discharging blocking cylinder; 39-Material rack lifting and rotating mechanism; 40-Servo feeding mechanism; 41-Lifting servo motor; 42-Screw jack; 43-Rotation servo motor; 44-Synchronous pulley; 45-Idler pulley; 46-Connecting plate; 47-Synchronous belt; 48-Front barcode reader; 49-Rear barcode reader. Detailed Implementation

[0033] The following detailed description provides further details on specific implementation methods.

[0034] like Figures 1 to 7 As shown, this invention provides a fuel rod double-ended welding device, which uses TIG welding to weld the upper and lower end plugs of the fuel rod to the cladding tube. It includes a welding worktable 2 and a rotatable material rack 4. A top-end position adjustment mechanism 1 and a welding chamber 3 are installed above the welding worktable 2, and a welding power source is installed in a cabinet below the welding worktable 2. A welding torch 8 is installed above the welding chamber 3. Welding observation systems are provided on the front and back of the welding chamber 3. One side of the welding chamber 3 is the fuel rod entry channel, and the opposite side is the top-end position adjustment mechanism 1. Figure 1 As shown, a top position adjustment mechanism 1 is installed on the right side of the welding chamber 3. The rotatable material rack 4 is used for the transfer of fuel rods between upstream and downstream processes, feeding fuel rods into the welding chamber 3 and rotating and reversing the fuel rods. A dual barcode reader is installed on the fuel rod entry and exit channel of the rotatable material rack 4.

[0035] like Figure 2 As shown, the top position adjustment mechanism 1 includes an end plug top 6, a tail adjustment center shaft 9, an adjustment bracket 10, a connecting base plate 11, a lead screw 12, a lead screw support 13, a guide rail 14, a guide rail slider 15, a transition base plate 16, a pad block 17, a tail adjustment motor 18, a coupling 19, a motor mounting plate 20, a synchronous pulley 21, and a carbon brush 22.

[0036] The end plug 6 is connected to the tail adjustment center shaft 9 via its tail thread, and further mates with the hole in the adjustment bracket 10. The adjustment bracket 10 is connected to the connecting base plate 11 via a threaded connection. The guide rail slider 15 and the nut of the lead screw 12 are installed below the connecting base plate 11. The tail adjustment motor 18 drives the connecting base plate 11 to move along the guide rail 14 via the nut of the lead screw 12. The nut of the lead screw 12 is located in the middle position below the connecting base plate 11, converting the rotation of the lead screw 12 into the linear motion of the connecting base plate 11. The lead screw support block 13 and the guide rail 14 are installed on the transition base plate 16, and the lead screw support block 13 serves to support the lead screw. The pad block 17 is used to ensure that the lead screw 12 and the output shaft of the tail adjustment motor 18 are at the same height. The tail adjustment motor 18 is installed on the motor mounting plate 20, the transition base plate 16 is installed on the pad block 17, and the guide rail slider 15 ensures that the connecting base plate 11 moves smoothly in a straight line along the guide rail 14. The lead screw 12 is connected to the output shaft of the tail adjustment motor 18 via a coupling 19. The tail adjustment motor 18 drives the lead screw 12 to rotate, and the lead screw nut installed below the connecting base plate 11 drives the connecting base plate 11 to move back and forth, thereby driving the end plug head 6 to move back and forth.

[0037] Since the end plug 6 needs to rotate during welding, a timing pulley 21 is installed on the shoulder of the tail adjustment center shaft 9, and a bearing is installed in the hole of the adjustment bracket 10. To make the end plug 6 conductive, the tail adjustment center shaft 9 is also made of beryllium cobalt copper and is connected to the carbon brush 22.

[0038] The end cap 6 has a compatible shape, ensuring reliable contact with the upper and lower end cap faces, providing good electrical conductivity and heat dissipation, and preventing oxidation burns on the end cap. The position of the end cap 6 can be precisely adjusted using the end cap position adjustment mechanism 1 to accommodate length deviations of different types of end caps. The end cap 6 rotates synchronously with the fuel rod via the timing pulley 21, preventing dry-grinding and ignition of the end cap.

[0039] like Figure 3 As shown, the end plug head 6 is used to determine the axial position of the welding torch 8 relative to the end plug weld, and also serves to conduct electricity and cool. A tungsten electrode is provided at the front end of the welding torch 8. The pipe clamp 7 holds the cladding tube of the fuel rod, and the end plug 5 is installed at the end of the cladding tube. The end plug head 6 is pressed tightly against the end face of the end plug 5 and can be inserted into the inner hole of the end plug 5 as a guide. An inert gas channel is provided inside the end plug head 6 for inert gas cooling during welding.

[0040] Preferably, the end plug head 6 is made of beryllium cobalt copper, a material with good electrical and thermal conductivity. To ensure compatibility with the upper and lower end plugs, a wrap-around structure is not used. Instead, it is fitted to the end plug by pressing against the end face and inserting it in the middle. The end plug head 6 has internal perforations for ventilation to cool the inside of the casing tube. Another advantage of using the end plug head 6 is that it exposes the welding area of ​​the end plug and the adjacent area to the argon protective atmosphere of the welding chamber 3, avoiding localized oxidation caused by poor airflow in some areas.

[0041] like Figure 4 As shown, the welding chamber observation system includes a front camera 23 arranged on the front of the welding chamber 3 and a back light source 24 arranged on the back of the welding chamber 3. It is used to observe the positioning of the tungsten electrode on the welding torch 8 relative to the weld seam and to determine the axial adjustment amount of the end plug 6.

[0042] As can be seen, the welding chamber observation system set up in this invention can observe the front of the welding chamber 3 at any time through the front camera 23 and the back light source 24, monitor the positional relationship of components such as the end plug head 6, the end plug and the welding torch 8, and facilitate the adjustment of the position of the end plug head 6.

[0043] The rotatable feeder 4 can be used not only for transferring fuel rods between upper and lower workstations, feeding and retracting rods into the welding chamber 3, but also for rotating and reversing the fuel rods to prepare for double-ended welding. Figure 5 As shown, the rotatable material rack 4 is constructed from aluminum profiles to form the main frame. A set of feeding slides 29 and a set of discharging slides 30 are fixed to the edge of the profile frame by connectors and have a 3° inclination angle. The end of the feeding slide 29 is slightly higher than the beginning of the discharging slide 30. The end of the feeding slide 29 is equipped with a baffle to block the fuel rod, and the end of the discharging slide is equipped with a blocking cylinder 38 to block the fuel rod.

[0044] A set of V-grooves 26 with plungers is installed on the path aligned with welding chamber 3, allowing the fuel rods to slide easily within the grooves. At the fixed ends of the transmission line, the V-grooves 26 are directly connected to the fixed frame via connectors. In the rotatable middle section, they are connected to the movable beam 33 on the unloading side via V-groove brackets 35. A set of unloading guide plates 25 are screwed to the side of each V-groove. A set of feeding cylinders 28 and feeding paddles 27 connected to them are directly connected to the fixed frame at the fixed ends of the transmission line, while the rotating middle section is connected to the movable beam 32 on the unloading side. A servo feeding mechanism 40 is connected to the fixed frame. A set of feeding cylinders 28 drives corresponding feeding paddles 27 to remove one fuel rod from the feeding slide 29 at a time, slide it along the unloading guide plate 25 into the V-groove with a plunger, and then feed it into the welding chamber 3 for welding via a servo feeding mechanism 40. After welding, the fuel rod is removed from the welding chamber 3, and the same set of feeding cylinders 28 drives the corresponding feeding paddles 27 to lift the fuel rod in the V-groove, causing it to roll along a set of unloading guide plates 25 onto the unloading slide 30, where it is blocked by a blocking cylinder 38. At the same time as the feeding paddles 27 lift the fuel rod in the V-groove 26, another fuel rod to be welded is lifted from the feeding slide 29. After the feeding paddles 27 fall, the fuel from this fuel rod falls into the V-groove 26. This process is repeated to complete the welding of one end of a batch of fuel rods.

[0045] The movable beams 32 on the loading side and 33 on the unloading side serve as mounting carriers for the loading cylinder 28 and the V-groove support frame 35 of the rotating part of the material rack. The movable beams 32 and 33 are connected to the moving beam slide rail 34 via sliders mounted on them. The material rack lifting and rotating mechanism 39 is fixed to the lower layer of the frame, and the lifting beam 31 is fixed to the connecting plate 45 of the lifting and rotating mechanism 39.

[0046] like Figure 5 As shown, the lifting arm 36 is connected to the lifting beam 31. A lifting receiving groove 37 is installed on each side of the lifting arm 36. The two lifting receiving grooves 37 ensure that the lifting arm can rotate continuously to receive materials. Before the lifting beam 31 is raised, the movable beam 32 on the feeding side and the movable beam 33 on the discharging side open to both sides along the moving beam slide rail 34, leaving space for the lifting beam 31 to rise. The lifting beam 31 drives the lifting arm 36 to rise, and at the same time, the lifting receiving grooves 37 lift the fuel rods on the discharging slide rail 30 on the discharging side. After rising to the correct position, the lifting beam 31 rotates as a whole, and then the lifting beam 31 falls down. The fuel rods are turned around and placed on the feeding slide rail 29. The movable beam 32 on the feeding side and the movable beam 33 on the discharging side close towards the center along the moving beam slide rail 34.

[0047] To ensure welding efficiency, the material rack tilting and end plug head 6 position adjustment are not performed once per piece, but in batches. The material rack lifting and rotating mechanism 39 is driven by a servo motor.

[0048] like Figure 6As shown, the material rack lifting and rotating mechanism 39 includes a lifting servo motor 41, a screw jack 42, a rotating servo motor 43, a synchronous pulley 44, an idler pulley 45, and a connecting plate 46. The lifting servo motor 41 and the rotating servo motor 43 are the driving mechanisms of the material rack lifting and rotating mechanism 39. The lifting servo motor 41 drives the screw jack 42 to convert the horizontal rotation of the motor into vertical rotation of the screw, which in turn drives the connecting plate 46 to rise and fall. A lifting beam 31 is installed on the connecting plate 46. After the connecting plate 46 is raised to its highest position, the lifting beam 31 is also raised to its highest position. The rotating servo motor 43 drives the connecting plate 46 to rotate via the synchronous pulley 44, thereby causing the connecting plate 46 to rotate 180 degrees, causing the fuel rods in the lifting receiving trough 37 to flip to one side of the feeding slide 29. The idler pulley 45 serves to tension the synchronous belt 47.

[0049] like Figure 7 As shown, the dual barcode reader includes a front barcode reader 48 and a rear barcode reader 49, which are respectively installed at both ends of the casing tube. The reading terminals are aligned with the V-groove with plunger 26. The rear barcode reader 49 is used to scan the barcode when the lower end plug is welded, and the front barcode reader 48 is used to scan the barcode again after the fuel rod is rotated. The program can determine which side is being welded by the triggered barcode reader, thereby realizing automatic determination of the current welding position.

[0050] This invention features dual barcode readers to ensure that barcode information can be collected and recorded before and after the casing is flipped, thus guaranteeing the accuracy of welding parameter recording.

[0051] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A double-ended welding device for fuel rods, characterized in that, include: A welding workbench (2) is provided with a top position adjustment mechanism (1) and a welding chamber (3). The top position adjustment mechanism (1) has an end plug top (6), a lead screw (12) and a tail adjustment motor (18). The tail adjustment motor (18) drives the end plug top (6) to move forward and backward toward the welding chamber (3) through the lead screw (12). A welding torch (8) is provided in the welding chamber (3). A rotatable rack (4) is used to turn fuel rods and feed and retract them into the welding chamber (3). The rotatable rack (4) has a lifting beam (31), a lifting arm (36), a lifting receiving groove (37), and a rack lifting and rotating mechanism (39). The lifting arm (36) is connected to the lifting beam (31), and the lifting receiving groove (37) is installed on the lifting arm (36). The rack lifting and rotating mechanism (39) is located below the lifting beam (31). The rack lifting and rotating mechanism (39) has a lifting servo motor (41), a screw jack (42), a rotary servo motor (43), and a synchronous wheel (44). The lifting servo motor (41) drives the screw jack (42) to drive the vertical screw to rotate, thereby driving the connecting plate (46) of the rack lifting and rotating mechanism (39) to rise and fall. After the lifting and falling is in place, the rotary servo motor (43) drives the connecting plate (46) to rotate through the synchronous wheel (44). The rotatable material rack (4) also has a discharge guide plate (25), a plunger-equipped V-groove (26), a feeding paddle (27), a feeding cylinder (28), a feeding side movable beam (32), a discharge side movable beam (33), a moving beam slide rail (34), and a V-groove support frame (35). In the middle rotating part of the rotatable material rack (4), the plunger-equipped V-groove (26) is mounted on the discharge side movable beam (33) via the V-groove support frame (35). The feeding paddle (27) and the feeding cylinder (28) are mounted on the feeding side movable beam (32). In the fixed parts at both ends of the rotatable material rack (4), the discharge guide plate (25), the plunger-equipped V-groove (26), the feeding paddle (27), and the feeding cylinder (28) are mounted on the discharge side movable beam (32). The loading cylinder (28) is connected to the fixed frame of the material rack; before the lifting beam (31) is lifted, the movable beams (32) on the loading side and the movable beams (33) on the unloading side on both sides open to both sides along the movable beam slide rail (34), the lifting beam (31) drives the lifting arm (36) to rise, and at the same time the lifting receiving groove (37) lifts the fuel rod on the unloading slide rail (30) on the unloading side. After it is lifted into position, the lifting beam (31) rotates as a whole, and then the lifting beam (31) falls down, and the fuel rod is turned around and placed on the loading slide rail (29). The servo feeding mechanism (40) is installed on the fixed frame at one end of the rotatable material rack (4) and aligned with the welding chamber inlet, and feeds a single fuel rod into or out of the welding chamber (3).

2. The fuel rod double-ended welding device according to claim 1, characterized in that, The top position adjustment mechanism (1) also includes a tail adjustment center shaft (9), an adjustment bracket (10), a connecting base plate (11), a lead screw support seat (13), a guide rail (14), a guide rail slider (15), a transition base plate (16), and a coupling (19). One end of the tail adjustment center shaft (9) is connected to the end plug top head (6), and the other end is connected to the adjustment bracket (10). The adjustment bracket (10) is connected to the connecting base plate (11). The bottom of the connecting base plate (11) is connected to the guide rail slider (15) and the lead screw (12) nut by screws. The lead screw support seat (13) and the guide rail (14) are installed on the transition base plate (16). The lead screw (12) is connected to the output shaft of the tail adjustment motor (18) through the coupling (19).

3. The fuel rod double-ended welding device according to claim 2, characterized in that, A pad (17) is provided below the transition base plate (16).

4. The fuel rod double-ended welding device according to claim 2, characterized in that, The tail adjustment motor (18) is mounted on the motor mounting plate (20) such that the output shaft of the tail adjustment motor (18) is at the same height as the lead screw (12).

5. The fuel rod double-ended welding device according to claim 2, characterized in that, The tail adjustment center shaft (9) is equipped with carbon brushes (22).

6. The fuel rod double-ended welding device according to claim 2, characterized in that, The tail adjustment center shaft (9) is equipped with a synchronous pulley (21).

7. The fuel rod double-ended welding device according to claim 1, characterized in that, It also includes a front barcode reader (48) and a rear barcode reader (49), which are fixed at both ends of the rotatable rack (4) by means of connectors to read the barcodes of the fuel rods in the V-groove with plunger (26).

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