Method of manual tungsten electrode welding of zirconium tube

Abstract

The application discloses a manual tungsten electrode welding method for zirconium pipes and relates to the field of zirconium pipe welding. The method solves the problem that there are few cases for reference in the welding method of zirconium pipes, which are new materials, and there is no suitable tooling to cooperate with to improve the welding efficiency. The method comprises the following steps: step one, clamping two zirconium pipes to be welded on a clamping and grinding tooling, and performing beveling processing on the zirconium pipes to be welded until the surface is silvery white; and step two, assembling the two zirconium pipes, and then welding the assembled zirconium pipes by using a tungsten electrode welding gun, and protecting the front and back of the weld by using the welding gun protection gas, the zirconium pipe external protection gas and the zirconium pipe internal protection gas during the welding process. The method adopts the measures of the front weld large nozzle protection and the argon filling in the pipe back weld protection, ensures the protection effect on the high temperature zone weld and the heat affected zone, ensures the welding quality, and sets the clamping and grinding tooling, thereby significantly improving the universality in the zirconium pipe welding.

Description

Technical Field

[0001] This invention relates to the field of zirconium tube welding, and more particularly to a manual tungsten electrode welding method for zirconium tubes. Background Technology

[0002] Zirconium is a non-rare metal, silvery-white in color. It has a melting point as high as 1852℃, a boiling point of 3850℃, and a density of 6.5 g / cm³. 3 Zirconium is a highly reactive metal that reacts strongly with oxygen, hydrogen, and nitrogen at relatively high temperatures. Zirconium begins to react with oxygen at 200°C, with hydrogen at 300°C, and with nitrogen at 400°C. Furthermore, zirconium is extremely sensitive to the presence of impurities; even trace amounts of impurities (such as nitrogen, oxygen, hydrogen, and carbon) can cause it to become embrittled, posing significant difficulties for welding and heat treatment. Therefore, strict control of gases and impurities is essential during welding.

[0003] Zirconium also exhibits excellent corrosion resistance. It demonstrates high resistance to organic acids, strong alkalis, and certain liquid metals. It also exhibits strong resistance to water vapor, seawater, and liquids subjected to high temperatures and pressures. Furthermore, zirconium has a stable, dense, firmly bonded, and self-healing zirconium oxide film on its surface, making it an important structural material in nuclear reactor engineering.

[0004] Zirconium possesses excellent corrosion resistance, especially its extremely high temperature resistance, which is unmatched by stainless steel and titanium. Therefore, it has enormous potential for development in high-temperature and corrosion-resistant engineering materials fields such as chemical, petroleum, and nuclear energy. However, as it is a new material, there are few precedents for its welding methods. Therefore, it is necessary to research a welding method for zirconium tubes to ensure that welding defects do not occur during the welding process. Furthermore, it is essential to ensure that the tubes exhibit strong corrosion resistance and high-temperature resistance to water vapor, seawater, and high-temperature, high-pressure liquids. Summary of the Invention

[0005] The purpose of this invention is to provide a manual tungsten electrode welding method for zirconium tubes, which solves the problems that zirconium tubes are a new material, there are few case studies on welding methods, and there are no suitable tooling to improve welding efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for manual tungsten electrode welding of zirconium tubes, comprising the following steps:

[0007] Step 1: Clamp the two zirconium tubes to be welded on the clamping and grinding fixture, and perform beveling on the zirconium tubes to be welded until the surface is exposed to a silvery white color.

[0008] Step 2: Assemble the two zirconium tubes together, and then use a tungsten inert gas (TIG) welding torch to weld the assembled zirconium tubes. During the welding process, the front and back of the weld seam are protected by the shielding gas of the welding torch, the shielding gas outside the zirconium tube, and the shielding gas inside the zirconium tube.

[0009] The shielding gas flow rate of the welding torch is 25-35 L / min, the external shielding gas flow rate of the zirconium tube is 70-80 L / min, and the internal shielding gas flow rate of the zirconium tube is 50-60 L / min.

[0010] Preferably, the tungsten electrode welding torch nozzle is Φ25 or larger, the tungsten electrode is Φ2.5-3.5mm, the tungsten electrode extension length is 5-6.5mm, the welding wire is Φ2-3mm, and the welding current is 100-130A.

[0011] Preferably, the beveling process in step one includes sequentially grinding the oxides, oxide film, burrs, oil, and rust on the inner and outer sides of the zirconium tube bevel, and then wiping and drying with acetone.

[0012] Preferably, the welding in step two is carried out in multiple segments. Before welding each segment, spot welding is performed on the weld joint. After welding each segment, the interpass temperature is measured. When the interpass temperature is below 100°C, the next segment is welded.

[0013] Preferably, the beveling process results in a blunt edge width of 1.0-1.5 mm for the zirconium tube, a blunt edge gap of 2.0-2.5 mm during assembly, and a beveling angle of 60±5°.

[0014] Preferably, the clamping and grinding fixture in step one includes a slide rail frame, with slide seats symmetrically slidably connected to both ends of the slide rail frame, and a telescopic rod installed on the slide rail frame. The upper end of the telescopic rod is connected to a support plate. A clamping mechanism is provided on the slide seat for clamping the zirconium tube to be welded. A grinding mechanism is provided on the support plate for grinding the bevel of the zirconium tube. A driving mechanism is provided on the slide rail frame for pulling the zirconium tubes on both slide seats closer together to weld the zirconium tubes.

[0015] Preferably, the grinding mechanism includes a sleeve, a disc, a second servo motor, a lead screw, a collar, a limiting slide rail, a first rotating plate, a right-angle limiting seat, and a mounting plate. The sleeve is connected to the support plate, and a bidirectional telescopic rod is rotatably fitted inside the sleeve. Both ends of the bidirectional telescopic rod are connected to guide cylinders, and the outer sides of the guide cylinders are arrayed with through-path slideways. The disc is connected to the guide cylinders, the second servo motor is connected inside the guide cylinders, the lead screw is connected to the second servo motor, the collar is threaded onto the outer side of the lead screw, and slides inside the guide cylinders. The limiting slide rail is radially through-pathed on the disc, and a limiting slider is slidably connected inside the limiting slide rail. One end of the first rotating plate is rotatably connected to the limiting slider, and the other end passes through the slideway and is rotatably connected to the collar. The right-angle limiting seat is connected to the limiting slider, and the mounting plate is rotatably connected to the right-angle limiting seat via a spring hinge. A grinding rod is connected to the right-angle limiting seat, and the grinding rod is limited by the two side frames of the right-angle limiting seat.

[0016] Preferably, a gear ring is fitted on the outer side of the bidirectional telescopic rod inside the sleeve, a servo motor is installed inside the sleeve, and the output end of the servo motor is connected to a gear, which meshes with the gear ring.

[0017] Preferably, the clamping mechanism includes a lower clamping seat, a first guide slide rod seat, a slide frame, an upper clamping seat, and a first spring. The lower clamping seat is fixedly connected to the slide frame, the first guide slide rod seat is connected to the slide frame, the slide frame is slidably sleeved on the outside of the first guide slide rod seat, the upper clamping seat is connected to the lower end of the slide frame and is staggered with the lower clamping seat, and the first spring is sleeved on the outside of the first guide slide rod seat. The two ends of the first spring are respectively connected to the first guide slide rod seat and the slide frame.

[0018] Preferably, the driving mechanism includes a second guide slide seat, a second rotating plate, and a second spring. The second guide slide seat is connected to the slide rail frame. A sliding plate is sleeved on the outer side of the second guide slide seat. One end of the second rotating plate is rotatably connected to the slide seat, and the other end is rotatably connected to the sliding plate. The second spring is sleeved on the outer side of the second guide slide seat, and both ends of the second spring are respectively connected to the second guide slide seat and the slide rail frame. Pressure plates are connected to both sides of the support plate. The pressure plates abut against the upper surface of the sliding plate. A bottom frame is connected to the support plate, and a push plate is connected to the bottom frame. The upper end of the push plate abuts against the slide frame.

[0019] Compared with related technologies, the manual tungsten inert gas welding method for zirconium tubes provided by this invention has the following beneficial effects:

[0020] The use of a large nozzle for front-side protection of the weld and argon purging inside the pipe for back-side protection of the weld ensures effective protection of the weld in the high-temperature zone and the heat-affected zone, and ensures welding quality.

[0021] Furthermore, by using large-diameter nozzles and high gas flow rates, it can be further ensured that the high-temperature weld seam, heat-affected zone, and high-temperature zone at the end of the welding wire are always in the protective atmosphere of argon gas sprayed from the welding torch, thus preventing the high-temperature weld seam and heat-affected zone from being oxidized.

[0022] Ensure that the temperature of the molten pool and heat-affected zone is reduced during the welding process under the protection of high-purity, high-flow-rate argon gas to prevent excessive temperature from causing defects in the zirconium tube;

[0023] Equipped with a clamping and grinding fixture, it can clamp and weld zirconium tubes of various materials, and automatically perform pre-welding processing, which improves the efficiency of the welding operation and increases its versatility. Attached Figure Description

[0024] Figure 1 This is a diagram illustrating the segmented welding steps of the present invention.

[0025] Figure 2 This is a schematic diagram showing the dimensions of the zirconium plate specimen assembly according to the present invention.

[0026] Figure 3 This is a schematic diagram of the clamping and grinding fixture structure of the present invention.

[0027] Figure 4 This is a cross-sectional view of the structure of the present invention.

[0028] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0029] Figure 6 This is a schematic diagram of the slide rail-less structure of the present invention.

[0030] Figure 7 This is a schematic diagram of the clamping mechanism of the present invention.

[0031] Figure 8 This is a schematic diagram of the grinding mechanism of the present invention.

[0032] Figure 9 This is a schematic diagram of the right-angle limiting seat of the present invention.

[0033] In the diagram: 1. Slide rail frame; 2. Slide seat; 3. Telescopic rod; 4. Support plate; 5. Sleeve; 6. Bidirectional telescopic rod; 7. Gear ring; 8. Servo motor one; 9. Gear; 10. Guide cylinder; 11. Disc; 12. Slide rail; 13. Servo motor two; 14. Lead screw; 15. Collar; 16. Limiting slide rail; 17. Limiting slider; 18. Rotating plate one; 19. Right angle limiting seat; 20. Mounting plate; 21. Grinding rod; 22. Lower clamp; 23. Guide slide rod seat one; 24. Slide frame; 25. Upper clamp; 26. Spring one; 27. Guide slide rod seat two; 28. Slide plate; 29. ​​Rotating plate two; 30. Pressure plate; 31. Spring two; 32. Base frame; 33. Push plate; 34. Zirconium tube. Detailed Implementation

[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0035] Example 1

[0036] Please see Figure 1-2 This invention provides a technical solution: a method for manual tungsten electrode welding of zirconium tubes, comprising the following steps:

[0037] Step 1: Clamp the two zirconium tubes to be welded on the clamping and grinding fixture, and perform beveling on the zirconium tubes to be welded until the surface is exposed to a silvery white color.

[0038] Step 2: Assemble the two zirconium tubes together, and then use a tungsten inert gas (TIG) welding torch to weld the assembled zirconium tubes. During the welding process, the front and back of the weld seam are protected by the shielding gas of the welding torch, the shielding gas outside the zirconium tube, and the shielding gas inside the zirconium tube.

[0039] The shielding gas flow rate of the welding torch is 25-35 L / min, the external shielding gas flow rate of the zirconium tube is 70-80 L / min, and the internal shielding gas flow rate of the zirconium tube is 50-60 L / min.

[0040] The tungsten electrode welding torch nozzle is Φ25 or larger, the tungsten electrode is Φ2.5-3.5mm, the tungsten electrode extension length is 5-6.5mm, the welding wire is Φ2-3mm, and the welding current is 100-130A.

[0041] Step one involves beveling, which includes grinding the oxides, oxide film, burrs, oil, and rust on the inside and outside of the zirconium tube bevel, followed by wiping with acetone and drying.

[0042] In step two, welding is carried out in multiple segments. Before welding each segment, tack welding is performed on the weld joint. After welding each segment, the interpass temperature is measured. When the interpass temperature is below 100℃, the next segment is welded.

[0043] The beveling process results in a blunt edge width of 1.0-1.5mm for the zirconium tube, a blunt edge gap of 2.0-2.5mm during assembly, and a beveling angle of 60±5°.

[0044] The above welding method is not only used for zirconium pipes, but also for metal plates, such as zirconium plates. Figure 2 The diagram shown is a schematic of the dimensions of the zirconium plate specimen assembly.

[0045] Taking a zirconium tube with a diameter of 60mm and a wall thickness of 3.5mm as an example, the specific steps include:

[0046] After beveling, the zirconium tubes are assembled.

[0047] The assembled zirconium tubes were welded using manual tungsten inert gas welding, and a protective gas was introduced into the zirconium tubes during the welding process.

[0048] The welding torch nozzle is Φ28mm, the shielding gas flow rate is 30L / min, the shielding gas flow rate for the external weld of the zirconium tube is 70-80L / min, the shielding gas flow rate for the internal weld of the zirconium tube is 50-60L / min, the shielding gas needs to be high-purity argon (99.999%), the tungsten electrode is Φ3.0mm, the welding wire is Φ2.4mm, a DC positive polarity arc welding power supply is used, and the welding current is 100-130A.

[0049] This invention employs a welding torch with a weld protection device to protect the front side of the weld and adds protection to the back side of the weld inside the tube. This ensures that both sides of the weld in the high-temperature zone and the heat-affected zone are always under a protective atmosphere of zirconium-pure argon gas, guaranteeing weld quality. Furthermore, by using a large-diameter nozzle and a high gas flow rate, it further ensures that the high-temperature weld, heat-affected zone, and high-temperature area at the end of the welding wire are always under the protective atmosphere of zirconium-pure argon gas sprayed from the welding torch, preventing oxidation of the high-temperature weld and heat-affected zone. By using rapid welding and a high-purity, high-gas-flow protection method, the temperature of the molten pool and heat-affected zone can be controlled while ensuring rapid weld penetration, achieving precise weld temperature control and preventing welding defects caused by excessive temperature. This invention effectively guarantees welding quality, and all post-weld tests meet the quality requirements.

[0050] Before welding zirconium tubes, impurities such as oxides, oxide films, burrs, oil, and rust within a 30-50 mm range on the inner and outer sides of the zirconium tube bevel are successively ground and cleaned with acetone until the surface is exposed to a silvery white color.

[0051] When performing beveling, the blunt edge dimension should be 1.0-1.5mm, and the assembly gap should be 2.0-2.5mm. This ensures that the weld penetration is completed in the shortest time and that the loss of shielding gas inside the pipe is minimized.

[0052] When performing segmented welding, the length of each segment is 1 / 4 of the total weld length. Before welding, tack welding is performed on the zirconium tube joints. The segmented welding method involves dividing the weld into multiple segments, welding each segment, and then welding the symmetrical segment next to it. Figure 1 The joint comprises sections I, II, III, and IV. Section I is welded first, followed by section II, and then sections III and IV are welded in sequence. After each layer of weld is completed for each section, the interpass temperature needs to be measured. The next section can only be welded if the interpass temperature is below 100°C. This segmented welding method helps to control the temperature of the molten pool and the high-temperature zone weld to always be within the high-purity argon gas protection area, achieves faster heat dissipation and cooling speed, and ensures that the high-temperature zone weld and heat-affected zone are always in a high-purity argon gas protection atmosphere.

[0053] In the manual tungsten inert gas (TIG) welding method for zirconium tubes according to an embodiment of the present invention, a combination of high-purity argon gas protection via a large nozzle on the weld front and high-purity argon gas filling inside the tube for weld back protection is employed to ensure effective protection of the high-temperature weld and heat-affected zone, thereby ensuring welding quality. Furthermore, the high-temperature zone at the end of the welding wire is always within the protective atmosphere of argon gas sprayed from the welding torch, preventing oxidation of the high-temperature weld and heat-affected zone. This ensures that the temperature of the molten pool and heat-affected zone is reduced during the welding process under the protection of high-purity, high-flow-rate argon gas, preventing excessively high temperatures from causing defects in the zirconium tube.

[0054] In summary, this invention improves aspects such as pre-welding preparation, matching of welding materials and tools, selection of welding parameters, purity and flow rate of shielding gas, temperature control of the weld during welding, and protection of the high-temperature zone. In particular, it incorporates measures such as a large nozzle diameter, high gas flow rate, segmented welding with large welding parameters, high shielding gas flow rate, high-purity shielding gas, and argon purging into the tube. These measures ensure the welding quality of manual tungsten inert gas (TIG) welding of Φ60mm×3.5mm zirconium tubes, guaranteeing single-sided welding with double-sided forming in a single pass, and ensuring the weld color on both sides meets quality requirements. Through the technical solution of this invention, the high-temperature molten pool and heat-affected zone are consistently protected by a high-purity argon atmosphere throughout the welding process, preventing oxidation of the high-temperature weld and heat-affected zone, ensuring welding quality, and preventing post-weld oxidation under process conditions where the weld temperature remains below 100℃. The weld also exhibits no defects upon flaw detection and meets various mechanical property test standards.

[0055] Based on the above welding process, after adjusting the gas shielding effect, the influence of the gas shielding effect on the weld quality is shown in Table 1 below:

[0056]

[0057] Based on the above welding process, after adjusting the shielding gas flow rate and the fixed direction of the zirconium tube, the influence of the gas shielding effect on the weld quality is shown in Table 2 below:

[0058]

[0059] Example 2

[0060] Specimen #1 is a 60×3.5mm zirconium tube, welded in a horizontal fixed position. The blunt edge of the zirconium tube to be welded is 1.0-1.5mm, the assembly gap is 2.0-2.5mm, the tungsten electrode is Φ3.0mm, the welding wire is Φ2.4mm, the welding torch nozzle is Φ28mm, the tungsten electrode extension length is 6mm, the argon purity is 99.999%, the argon flow rate of the welding torch is 30L / min, the gas flow rate of the external protective cover of the zirconium tube is 70-80L / min, the flow rate of the shielding gas inside the tube is 50-60L / min, and the welding current is 100-110A. When performing horizontal overhead welding at the 6 o'clock position of the zirconium tube, attention should be paid to adding welding wire when the weld hole size is greater than 2.5mm. The welding wire should be added from the inside of the weld joint to the weld hole and moved forward as much as possible with the arc to ensure that no concave defects are generated in the bottom weld of the tube. After welding, the weld is silvery-white. The weld formation is uniform upon visual inspection. No defects such as blue or purple discoloration, undercut, porosity, incomplete penetration, or lack of fusion were found. The flaw detection showed no defects and met the requirements of various mechanical property tests.

[0061] Example 3

[0062] Specimen #2 is a 60×3.5mm zirconium tube, welded in a vertical fixed position. The blunt edge of the zirconium tube to be welded is 1.0-1.5mm, the assembly gap is 2.0-2.5mm, the tungsten electrode is Φ3.0mm, the welding wire is Φ2.4mm, the welding torch nozzle is Φ28mm, the tungsten electrode extension length is 5.5mm, the argon purity is 99.999%, the argon flow rate of the welding torch is 30L / min, the gas flow rate of the external protective cover of the zirconium tube is 70-80L / min, the internal protective gas flow rate is 50-60L / min, and the welding current is 110-130A. When welding the upper part of the zirconium tube weld, care should be taken to prevent undercut. When the argon arc welding weld hole size is about 1mm, the welding wire should be added to the rear end of the weld hole along the side of the upper end of the tube to be welded, thereby preventing undercut from occurring on the upper end of the pipe weld. After welding, the weld is silvery-white. The weld formation is uniform upon visual inspection. No defects such as blue or purple discoloration, undercut, porosity, incomplete penetration, or lack of fusion were found. The flaw detection showed no defects and met the requirements of various mechanical property tests.

[0063] Example 4

[0064] Please see Figure 3-9The present invention provides a technical solution: In step one, the clamping and grinding fixture includes a slide rail frame 1, with slide seats 2 symmetrically slidably connected to both ends of the slide rail frame 1, and a telescopic rod 3 is installed on the slide rail frame 1. The upper end of the telescopic rod 3 is connected to a support plate 4. A clamping mechanism is provided on the slide seat 2. The clamping mechanism is used to clamp the zirconium tube 34 to be welded. The clamping mechanism includes a lower clamp seat 22, a guide slide rod seat 23, a slide frame 24, an upper clamp seat 25, and a spring 26. The lower clamp seat 22 is fixedly connected to the slide seat 2, the guide slide rod seat 23 is connected to the slide seat 2, the slide frame 24 is slidably sleeved on the outside of the guide slide rod seat 23, the upper clamp seat 25 is connected to the lower end of the slide frame 24 and is staggered with the lower clamp seat 22, and the outer side of the guide slide rod seat 23 is sleeved with a spring 26. The two ends of the spring 26 are respectively connected to the guide slide rod seat 23 and the slide frame 24.

[0065] like Figure 7 As shown, the slide frame 24 can be pulled upward first, so that it slides upward on the guide slide seat 23 and compresses the spring 26. At this time, the upper clamp 25 moves upward away from the lower clamp 22, creating a gap between them, which facilitates the placement of the zirconium tube 34. Then, the slide frame 24 is released. Under the elastic force of the compressed spring 26, the upper clamp 25 moves downward and cooperates with the lower clamp 22 to firmly clamp the zirconium tube 34.

[0066] A grinding mechanism is provided on the support plate 4. The grinding mechanism is used to grind the bevel of the zirconium tube. The grinding mechanism includes a sleeve 5, a disc 11, a second servo motor 13, a lead screw 14, a collar 15, a limiting slide rail 16, a rotating plate 18, a right-angle limiting seat 19, and a mounting plate 20. The sleeve 5 is connected to the support plate 4, and a bidirectional telescopic rod 6 is rotatably fitted inside the sleeve 5. Both ends of the bidirectional telescopic rod 6 are connected to guide cylinders 10, and the outer side of the guide cylinders 10 is provided with a through-type slide rail 12. The disc 11 is connected to the guide cylinder 10, the second servo motor 13 is connected inside the guide cylinder 10, and the lead screw 14 is connected to the servo motor 15. On the second machine 13, the collar 15 is threaded on the outside of the lead screw 14 and slides inside the guide cylinder 10. The limiting slide rail 16 is radially opened on the disc 11, and the limiting slider 17 is slidably connected inside the limiting slide rail 16. One end of the rotating plate 18 is rotatably connected to the limiting slider 17, and the other end passes through the slide rail 12 and is rotatably connected to the collar 15. The right-angle limiting seat 19 is connected to the limiting slider 17. The mounting plate 20 is rotatably connected to the right-angle limiting seat 19 through a spring hinge, and a grinding rod 21 is connected to the right-angle limiting seat 19. The grinding rod 21 is limited by the two side frames of the right-angle limiting seat 19 respectively.

[0067] like Figure 5 and 8As shown, after the clamping mechanisms on both sides clamp the two zirconium tubes 34 to be welded, the bidirectional telescopic rod 6 drives the guide cylinders 10 and the disc 11 on both sides to move closer to the zirconium tube bevel at the welding point of the zirconium tube 34 on their respective sides, but still maintains an appropriate distance from the zirconium tube bevel. Then, the servo motor 13 starts and drives the lead screw 14 to rotate. The collar 15 threaded on it will slide in the guide cylinder 10, and through the rotating plate 18, drive the limiting sliders 17 sliding in the limiting slide rail 16 on the disc 11 to move closer to each other or move further away from each other. This will then pull the grinding rods 21, which are rotated and installed on each right-angle limiting seat 19 through the mounting plate 20, to be on the inner or outer side of the zirconium tube 34 respectively.

[0068] When it is necessary to polish the inside of the zirconium tube 34, adjust each polishing rod 33 to be close together so that its range is smaller than the diameter of the zirconium tube 34. Then, the bidirectional telescopic rod 10 will drive it to extend into the opening of the zirconium tube 34, and then drive each polishing rod 33 to move away and disperse. Since the polishing rod 33 will abut against the lower side frame of the right angle limit seat 19 at this time, the polishing rod 33 can be adjusted to be in a state of contact with the inner wall of the zirconium tube 34 before polishing.

[0069] When grinding is required on the outer side of the zirconium tube 34 and the zirconium tube bevel, adjust the grinding rods 33 to be further apart, making their range larger than the diameter of the zirconium tube 34. Then, the bidirectional telescopic rod 10 will extend them to a position overlapping with the outer side of the zirconium tube 34. Then, the grinding rods 33 will be brought closer together. At this time, the grinding rods 33 will gradually come into contact with the outer side of the zirconium tube 34, and the outer side can be ground. When grinding is required on the zirconium tube bevel, continue to bring the grinding rods 33 closer together. At this time, there is no contact limit from the lower side frame of the right angle limit seat 19, and the grinding rods 33 will rotate until they are parallel to the zirconium tube bevel. At this time, the zirconium tube bevel can be ground. They can also continue to rotate until they come into contact with the vertical frame of the right angle limit seat 19. At this time, the grinding rods 33 can come into contact with the blunt edge of the zirconium tube bevel and be ground.

[0070] A gear ring 7 is fitted on the outer side of the bidirectional telescopic rod 6 inside the sleeve 5. A servo motor 8 is installed inside the sleeve 5, and the output end of the servo motor 8 is connected to a gear 9. The gear 9 meshes with the gear ring 7, so that the servo motor 8 can drive the guide cylinder 10 and the disc 11 to rotate, thereby driving the grinding rods 33 in various states to rotate, so as to realize the grinding operation.

[0071] A drive mechanism is provided on the slide rail frame 1. The drive mechanism is used to pull the zirconium tubes 34 on both sides of the slide seat 2 closer to each other for welding. The drive mechanism includes a guide slide seat 27, a rotating plate 29, and a spring 31. The guide slide seat 27 is connected to the slide rail frame 1. A slide plate 28 is sleeved on the outside of the guide slide seat 27. One end of the rotating plate 29 is rotatably connected to the slide seat 2, and the other end is rotatably connected to the slide plate 28. The spring 31 is sleeved on the outside of the guide slide seat 27. The two ends of the spring 31 are respectively connected to the guide slide seat 27 and the slide rail frame 1. Pressure plates 30 are connected to both sides of the support plate 4. The pressure plates 30 and the upper end surface of the slide plate 28 are in contact.

[0072] like Figure 6 As shown, after the grinding and acetone cleaning are completed and dried, the support plate 4 and the grinding mechanism on it can be moved down by the telescopic rod until they are completely below the slides 2 on both sides. During the process, the downward movement of the support plate 4 will drive the pressure plate 30 to push the slide plate 28 down and compress the second spring 31, and simultaneously pull the second rotating plate 29 to rotate, causing the slides 2 on both sides to move closer to each other, so that the zirconium tubes 34 clamped on the slides 2 move closer to each other, thus facilitating welding. The degree of closeness between the two zirconium tubes 34, that is, the size of the gap between them, needs to be set according to the specific welding process, welding wire, and argon arc welding equipment. For details, please refer to the operation manual of the relevant equipment.

[0073] A bottom frame 32 is connected to the support plate 4, and a push plate 33 is connected to the bottom frame 32. The upper end of the push plate 33 engages with the sliding frame 24, allowing the support plate 4 to be moved upward by the telescopic rod 3 and the push plate 33 to push the sliding frame 24 upward. This facilitates clamping the zirconium tube 34 between the upper clamp 25 and the lower clamp 22, and also avoids manual labor.

[0074] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications, improvements, and substitutions without departing from the concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A method for manual tungsten electrode welding of zirconium tubes, characterized in that, Includes the following steps: Step 1: Clamp the two zirconium tubes to be welded on the clamping and grinding fixture, and perform beveling on the zirconium tubes to be welded until the surface is exposed to a silvery white color. The clamping and grinding fixture includes a slide rail frame (1), with slide seats (2) symmetrically slidably connected to both ends of the slide rail frame (1), and a telescopic rod (3) installed on the slide rail frame (1). The upper end of the telescopic rod (3) is connected to a support plate (4). A clamping mechanism is provided on the slide seat (2), which is used to clamp the zirconium tube (34) to be welded. A grinding mechanism is provided on the support plate (4), which is used to grind the bevel of the zirconium tube. A driving mechanism is provided on the slide rail frame (1), which is used to pull the zirconium tube (34) on both sides of the slide seat (2) closer to each other so as to weld the zirconium tube (34). The grinding mechanism includes a sleeve (5), a disc (11), a second servo motor (13), a lead screw (14), a collar (15), a limiting slide rail (16), a rotating plate (18), a right-angle limiting seat (19), and a mounting plate (20). The sleeve (5) is connected to the support plate (4), and a bidirectional telescopic rod (6) is rotatably fitted inside the sleeve (5). Both ends of the bidirectional telescopic rod (6) are connected to guide cylinders (10), and a slide rail (12) is arrayed through the outer side of the guide cylinder (10). The disc (11) is connected to the guide cylinder (10), the second servo motor (13) is connected inside the guide cylinder (10), the lead screw (14) is connected to the second servo motor (13), and the collar (15) is connected to the guide cylinder (16). 5) The threaded sleeve is installed on the outside of the lead screw (14) and slides in the guide cylinder (10). The limiting slide rail (16) is opened radially through the disc (11) and the limiting slide rail (16) is slidably connected to the limiting slider (17). One end of the rotating plate (18) is rotatably connected to the limiting slider (17), and the other end passes through the slide rail (12) and is rotatably connected to the collar (15). The right angle limiting seat (19) is connected to the limiting slider (17). The mounting plate (20) is rotatably connected to the right angle limiting seat (19) through the spring hinge. A grinding rod (21) is connected to the right angle limiting seat (19). The grinding rod (21) is limited by the two side frames of the right angle limiting seat (19). Step 2: Assemble the two zirconium tubes together, and then use a tungsten inert gas (TIG) welding torch to weld the assembled zirconium tubes. During the welding process, the front and back of the weld seam are protected by the shielding gas of the welding torch, the shielding gas outside the zirconium tube, and the shielding gas inside the zirconium tube. The shielding gas flow rate of the welding torch is 25-35 L / min, the external shielding gas flow rate of the zirconium tube is 70-80 L / min, and the internal shielding gas flow rate of the zirconium tube is 50-60 L / min.

2. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The tungsten electrode welding torch has a nozzle of Φ25mm or larger, a tungsten electrode of Φ2.5-3.5mm, a tungsten electrode extension length of 5-6.5mm, a welding wire of Φ2-3mm, and a welding current of 100-130A.

3. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The beveling process described in step one includes grinding the oxides, burrs, and oil on the inside and outside of the zirconium tube bevel in sequence, and then cleaning and drying with acetone.

4. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The welding described in step two is carried out in multiple segments. Before welding each segment, tack welding is performed on the weld joint. After welding each segment, the interpass temperature is measured. When the interpass temperature is below 100℃, the next segment is welded.

5. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The beveling process results in a blunt edge width of 1.0-1.5mm for the zirconium tube, a blunt edge gap of 2.0-2.5mm during assembly, and a beveling angle of 60±5°.

6. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The bidirectional telescopic rod (6) has a gear ring (7) fitted on the outer side inside the sleeve (5). A servo motor (8) is installed inside the sleeve (5), and the output end of the servo motor (8) is connected to a gear (9). The gear (9) meshes with the gear ring (7).

7. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The clamping mechanism includes a lower clamp (22), a guide slide seat (23), a slide frame (24), an upper clamp (25), and a spring (26). The lower clamp (22) is fixedly connected to the slide (2). The guide slide seat (23) is connected to the slide (2). The slide frame (24) is slidably sleeved on the outside of the guide slide seat (23). The upper clamp (25) is connected to the lower end of the slide frame (24) and is staggered with the lower clamp (22). The spring (26) is sleeved on the outside of the guide slide seat (23). The two ends of the spring (26) are respectively connected to the guide slide seat (23) and the slide frame (24).

8. The method for manual tungsten electrode welding of zirconium tubes according to claim 1, characterized in that, The driving mechanism includes a guide slide seat 2 (27), a rotating plate 2 (29), and a spring 2 (31). The guide slide seat 2 (27) is connected to the slide rail frame (1). A slide plate (28) is sleeved on the outside of the guide slide seat 2 (27). One end of the rotating plate 2 (29) is rotatably connected to the slide seat (2), and the other end is rotatably connected to the slide plate (28). The spring 2 (31) is sleeved on the outside of the guide slide seat 2 (27). The two ends of the spring 2 (31) are respectively connected to the guide slide seat 2 (27) and the slide rail frame (1). Pressure plates (30) are connected to both sides of the support plate (4). The pressure plates (30) and the upper surface of the slide plate (28) are in contact. A bottom frame (32) is connected to the support plate (4), and a push plate (33) is connected to the bottom frame (32). The upper end of the push plate (33) is in contact with the slide frame (24).

Images