A die and method for rolling a spiral metal tube conductor for a coaxial cable

Abstract

The application discloses a die for a coaxial cable spiral metal pipe conductor and a texturing method, and technical scheme points are as follows: a metal pipe body, a texturing assembly arranged outside the metal pipe body and used for improving texturing productivity of the coaxial cable spiral metal pipe conductor; the texturing assembly comprises a texturing cutter seat arranged outside the metal pipe body, a plurality of first fixing holes are formed in one end of the texturing cutter seat, a plurality of positioning columns are fixedly installed at the other end of the texturing cutter seat, and a head outer circle is arranged outside the texturing cutter seat; the super wear resistance of a tungsten steel blade edge is combined with a reversible design of a double-blade handle, so that the total effective processing mileage of a single set of tooling is improved by several times compared with a traditional die, which directly leads to a significant decrease in die amortization cost of a unit length product and a significant reduction in time loss and labor cost caused by stoppage and die replacement.

Description

Technical Field

[0001] This invention relates to the field of communication cable manufacturing technology, specifically to a mold and corrugation method for a coaxial cable spiral metal tube conductor. Background Technology

[0002] In the manufacturing of radio frequency coaxial cables, in order to balance excellent shielding performance and good bending flexibility, the conductor usually adopts a spiral corrugated metal tube structure. For example, in the manufacturing of the inner conductor of large feeder cables (such as 1-5 / 8 specification) or the outer conductor of flexible cables (such as 1 / 2 ultra-flexible specification), a precise and uniform spiral corrugation must be formed on the surface of the copper tube through a corrugating process. The geometric parameters of the spiral shape, especially the diameter of the trough, are one of the core structural factors that determine the key electrical performance of the cable—characteristic impedance.

[0003] With the rapid development of technologies such as 5G communication and high-speed data networks, the market's requirements for the consistency of high-end cable performance have become extremely stringent. Taking 1 / 2-inch ultra-flexible cables as an example, their characteristic impedance tolerance requirements have been significantly tightened from the industry-standard ±2Ω to ±0.5Ω. This change poses unprecedented challenges to the corrugating process in terms of precision and durability, and existing technologies have revealed the following core defects:

[0004] First, rapid die wear leads to systemic quality degradation and cost overruns. The cutting edge of traditional corrugated dies wears significantly after 20 kilometers of continuous processing, directly causing the size of the forming troughs to gradually increase. This results in the characteristic impedance of the cable deviating from the set target and failing to consistently meet the precision tolerance of ±0.5Ω. To maintain product compliance within the limited lifespan of the die, manufacturers have to adopt passive compensation strategies: using insulated core wires with a specific capacitance (e.g., 82pF / m) in the early stages of a new die, and then replacing them with insulated core wires with another capacitance (e.g., 85pF / m) after the die wears out, attempting to pull the impedance back into the tolerance zone. Even so, the total effective lifespan of a single die is usually less than 50 kilometers before it is scrapped. This not only makes the die an expensive "disposable" consumable, but also complicates material management, reduces production efficiency, and dramatically increases overall costs due to frequent replacement of insulated core wires and downtime for debugging.

[0005] Secondly, the mold itself has limitations in materials and structure. When the existing mold is subjected to cyclic rolling force for a long time, in addition to the wear of the cutting edge, there is also the risk of plastic deformation (being "stretched") due to insufficient strength, which further aggravates the uncontrollable changes in the size of the spiral corrugation.

[0006] In summary, existing technologies have fallen into a vicious cycle of "pursuing high precision → rapid die wear → parameter drift → adopting high-cost compensation measures → die still rapidly becoming unusable → continuous increase in overall costs." This precision maintenance mode, which comes at the cost of high consumption, severely restricts the competitiveness of the high-end cable industry. Therefore, there is an urgent need for a texturing solution that can innovate in both materials and structure. By significantly improving the wear resistance and service life of the die, it can ensure the long-term stability of product parameters, thereby getting rid of the inefficient compensation production mode and achieving a breakthrough in both quality reliability and economic benefits. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a mold and corrugation method for a coaxial cable spiral metal tube conductor, thereby solving the problems mentioned in the background art.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0009] A mold for a coaxial cable spiral metal tube conductor includes a metal tube body and a corrugating assembly disposed outside the metal tube body to improve the corrugating productivity of the coaxial cable spiral metal tube conductor. The corrugating assembly includes: a corrugating cutter holder disposed outside the metal tube body; one end of the corrugating cutter holder has several first fixing holes; the other end of the corrugating cutter holder has several positioning pins fixedly installed; the outer surface of the corrugating cutter holder has a head outer circle; one end of the corrugating cutter holder has a second center hole; a base body is disposed outside the metal tube body; one end of the base body has several connecting holes and a connecting position; the other end of the base body has several threads. The threaded hole corresponds to the first fixing hole. One end of the base body has a grooving cutter mounting position. One end of the grooving cutter mounting position has a fourth center hole. A grooving cutter cover is movably engaged inside the grooving cutter mounting position. Several second fixing holes are opened on one side of the grooving cutter cover. A third center hole is opened on one side of the grooving cutter cover. A serrated tungsten steel grooving cutter is provided between the grooving cutter holder and the grooving cutter cover. Several positioning holes are opened on one side of the serrated tungsten steel grooving cutter. A first center hole is opened on one side of the serrated tungsten steel grooving cutter. The positioning pin is movably engaged with the positioning holes and the second fixing holes. A moving component for auxiliary conveying of the metal tube body is provided on one side of the connection position.

[0010] By adopting the above technical solution, the ultra-high hardness and wear resistance of tungsten steel are utilized to fundamentally resist wear, maintain the long-term stability of the micro-shape of the cutting edge, disperse instantaneous rolling force, reduce radial resistance, suppress vibration, improve surface quality, provide a channel for coolant, improve heat dissipation, and the wear mainly occurs in the inlet section. When one end of the inlet section is worn, the tool can be flipped to use the other end of the new inlet section, which, together with the original cutting edge with very little wear, forms a new cutting edge, thus doubling the service life.

[0011] Preferably, the moving component includes: an operating groove, the operating groove being formed inside one side of the connecting position, a plurality of support seats being fixedly installed on the inside one side of the operating groove, an operating ring being fixedly installed on one side of the plurality of support seats, a movable groove being formed on the top surface of the operating ring, a plurality of reserved holes being formed on the outer circular wall surface of the operating ring, a first external gear ring being movably sleeved inside the movable groove, an installation ring being fixedly installed at one end of the first external gear ring, a plurality of resistance columns being fixedly installed at one end of the installation ring, a plurality of conveying wheels being movably sleeved outside the operating ring, a plurality of power grooves being formed on the inner circular wall surface of the conveying wheels, the power grooves being slidably connected to the resistance columns, a micro servo motor being fixedly installed on one side of the operating groove, a first gear being fixedly installed at one end of the drive shaft of the micro servo motor, the first gear passing through the reserved holes and meshing with the first external gear ring.

[0012] By adopting the above technical solution, before the metal tube enters the interior of the crimping cutter holder and the base body, it first reaches the interior of the operating groove via the set conveyor wheels. Then, the metal tube moves to the interior of the operating ring, where it is positioned between several conveyor wheels. A micro servo motor is then used; the drive shaft of the micro servo motor rotates, driving the first gear to rotate. This rotation of the first gear meshes with the first external gear ring, causing it to rotate. The rotation of the first external gear ring drives the mounting ring and the resistance column to rotate. The resistance column then moves to the position of the conveyor wheels and enters the interior of the power groove. Due to the inclined angle of the power groove, when the resistance column enters and moves along the inner wall of the power groove, the resistance column presses against the inner wall, causing the conveyor wheels to rotate. Consequently, several conveyor wheels simultaneously rotate towards the center point of the operating ring, and the conveyor wheels rotate against the metal tube. The friction generated when the conveyor wheels contact the metal tube assists in its movement, allowing it to be fed into the base body and the crimping cutter holder.

[0013] Preferably, the outer circular wall of the conveyor wheel is provided with a plurality of detection grooves, a pressure sensor is fixedly installed on one side of the inside of the detection groove, and a pressure plate is fixedly installed inside the detection groove.

[0014] By adopting the above technical solution, and through the pressure sensor, when the conveyor wheel rotates on the surface of the metal tube, the contact between the conveyor wheel and the metal tube generates an interaction force. As the conveyor wheel continues to rotate, the pressure plate will come into contact with the surface of the metal tube. After being squeezed, the pressure plate will continue to squeeze the pressure sensor. Through the sensing of the pressure sensor, the pressure at the contact position between the metal tube and multiple conveyor wheels can be detected. Since the metal tube is located at the center position among several conveyor wheels, and the conveyor wheels are evenly arranged in a circle around the outside of the metal tube, under normal circumstances, the pressure on several conveyor wheels is the same. When the pressure sensor installed on one of the conveyor wheels shows excessive or insufficient pressure, it indicates that the position of the metal tube has shifted, or that there are protrusions on the outside of the metal tube, thus facilitating the elimination of problems with the metal tube before the metal tube is rolled.

[0015] Preferably, a fixing plate is fixedly sleeved inside the operating slot, and an inlet hole is opened at one end of the fixing plate. A wireless laser displacement sensor is provided on the side of the inlet hole near the operating slot.

[0016] By adopting the above technical solution, the metal tube passes through the inlet hole and enters the interior of the operating slot through the wireless laser displacement sensor. At this time, the staff can scan the outside of the metal tube by using the wireless laser displacement sensor, which makes it easier to detect the smoothness of the outside of the metal tube.

[0017] Preferably, a second external gear ring is provided on the side of the fixing plate near the operating groove, the wireless laser displacement sensor is fixedly installed with the second external gear ring, two limiting frames are fixedly installed on one end of the fixing plate, a limiting groove is opened on one end of the second external gear ring, the limiting groove is slidably connected with the limiting frame, a second gear is provided on one side of the fixing plate, the second gear is meshed with the second external gear ring, and a connecting rod is fixedly installed between the first gear and the second gear.

[0018] By adopting the above technical solution, when the drive shaft of the micro servo motor rotates, it will drive the connecting rod and the second gear to rotate through the first gear. Then, the second gear meshes and drives the second external gear to rotate. The second external gear will then drive the wireless laser displacement sensor to move in a circular motion on the surface of the metal tube, thereby facilitating the change of the detection position of the wireless laser displacement sensor on the metal tube.

[0019] Preferably, a fixed tube is fixedly installed at one end of the crimping tool holder, a rotating groove is formed on the outer circular wall of the fixed tube, a third external gear ring is movably sleeved on the inner circular wall of the rotating groove, a movable shell is fixedly installed at one end of the third external gear ring, an eddy current sensor is fixedly installed on the inner circular wall of the movable shell, a spur gear is meshed with the outer circular wall of the third external gear ring, and a micro drive motor is fixedly installed on the outer circular wall of the fixed tube, the drive shaft of the micro drive motor is meshed with the spur gear.

[0020] By adopting the above technical solution and using the eddy current sensor, after the metal tube is rolled, the drive shaft of the micro drive motor rotates, which drives the spur gear to rotate. The spur gear meshes and drives the third external gear ring to rotate. The third external gear ring drives the movable shell and the eddy current sensor to rotate. Then the eddy current sensor moves along the outer circumference of the metal tube, which facilitates the roughness detection of the rolled metal tube.

[0021] Preferably, a buffer shell is fixedly installed on the inner circular wall of the movable shell, a plurality of springs are fixedly installed on the inner bottom surface of the buffer shell, an extension plate is movably sleeved inside the buffer shell, a cleaning brush is fixedly installed on the top surface of the extension plate, and the extension plate is fixedly installed with the springs.

[0022] By adopting the above technical solution, the cleaning brush is installed so that when the metal tube is rolled, it enters the interior of the movable shell. When the movable shell rotates, it will drive the buffer shell, extension plate and cleaning brush to contact the outside of the metal tube, thereby facilitating the cleaning of the debris remaining on the surface of the rolled metal tube.

[0023] A method for die-rolling a coaxial cable spiral metal tube conductor, the method comprising the following steps:

[0024] Step 1, Installation: Install the tooling onto the corrugating machine spindle that is compatible with 1-5 / 8 inch cables, and finely calibrate the concentricity.

[0025] The second step, initial corrugation production: traction is started, and welding is started after the forming is stable. After the welding is stable, the corrugation and cooling system is started. The welded copper tube is intermittently squeezed by the serrated cutting edge in the guide section, forming a precisely sized spiral corrugation in the shaping section. The diameter of the trough is stabilized at 15.0±0.2mm, the peak at 17.3±0.25mm, and the pitch at 10.2±0.2mm by online measurement and monitoring. Continuous production is possible.

[0026] The third step is tool rotation and reuse: After 100 kilometers of continuous production, monitoring revealed that the diameter of the troughs was increasing to 15.0±0.2mm. The machine was stopped, the tooling was disassembled according to the procedure, the serrated tungsten carbide grooved cutter was rotated 180°, reassembled, and then installed back into the machine.

[0027] Fourth, secondary rolling production: using the flipped tool to continue production, the trough size is restored to around 15.0mm, and production can continue for another 95 kilometers.

[0028] In summary, the present invention has the following main beneficial effects:

[0029] 1. Revolutionary improvement in economic benefits: The exceptional wear resistance of tungsten steel cutting edges, combined with the reversible "double-edged" design, increases the total effective processing mileage of a single tooling set by several times compared to the traditional mold's <50km. This directly leads to a significant reduction in the amortization cost of molds per unit length of product and significantly reduces downtime and mold replacement time and labor costs.

[0030] 2. Extremely stable product performance: The high-hardness and wear-resistant cutting edge can maintain the stability of the tooth micro-geometry for more than 50km during the ultra-long production cycle, thereby eliminating the systematic drift of the trough size caused by mold wear from the source. This allows the characteristic impedance of the coaxial cable to be reliably stable within the strict tolerance range of ±0.5Ω for a long time, meeting the needs of high-end applications.

[0031] 3. Significantly simplified production process: Due to the long tool life and stable dimensions, the complex and passive operation of frequently replacing insulation core wires with different capacitance values ​​to compensate for mold wear in traditional processes has been completely eliminated. Production planning and material management have been simplified, the degree of process standardization has been improved, and production efficiency and product first-pass yield have been effectively improved.

[0032] 4. Enhanced process robustness: The optimized serrated structure reduces rolling impact, the high-rigidity tooling design avoids the risk of overall deformation, and the mirror-polished guide channel reduces the possibility of tube scratches. These factors together improve the reliability and repeatability of the entire rolling process. Attached Figure Description

[0033] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0034] Figure 2 This is a schematic diagram of the assembly structure of the present invention;

[0035] Figure 3 This is a schematic diagram of the serrated tungsten carbide grommet structure of the present invention;

[0036] Figure 4 yes Figure 3 A partial structural diagram of A in the middle;

[0037] Figure 5 This is a schematic diagram of the unfolded structure of the thread profile of the present invention;

[0038] Figure 6 This is a schematic diagram of the texturing tool holder structure of the present invention;

[0039] Figure 7 This is a schematic diagram of the embossing blade cover structure of the present invention;

[0040] Figure 8 This is a schematic diagram of the base main structure of the present invention;

[0041] Figure 9 This is a schematic diagram of the operating slot structure of the present invention;

[0042] Figure 10 This is a schematic diagram of the support structure of the present invention;

[0043] Figure 11 This is a schematic diagram of the operating ring structure of the present invention;

[0044] Figure 12 This is a schematic diagram of the first external toothed ring structure of the present invention;

[0045] Figure 13 This is a schematic diagram of the movable groove structure of the present invention;

[0046] Figure 14 This is a schematic diagram of the mounting ring structure of the present invention;

[0047] Figure 15 This is a schematic diagram of the conveyor wheel structure of the present invention;

[0048] Figure 16 This is a schematic diagram of the fixing plate structure of the present invention;

[0049] Figure 17 This is a schematic diagram of the limiting frame structure of the present invention;

[0050] Figure 18 This is a schematic diagram of the fixed tube structure of the present invention;

[0051] Figure 19 This is a schematic diagram of the movable shell structure of the present invention;

[0052] Figure 20 This is a schematic diagram of the buffer shell structure of the present invention;

[0053] Figure 21 This is a schematic diagram of the third external toothed ring structure of the present invention.

[0054] Reference numerals: 1. Metal tube body; 2. Serrated tungsten steel corrugated blade; 3. Corrugated blade holder; 4. Corrugated blade cover; 5. Base body; 6. Operating groove; 7. Support base; 8. Operating ring; 9. Movable groove; 10. Reserved hole; 11. First external toothed ring; 12. Mounting ring; 13. Resistance column; 14. Conveyor wheel; 15. Power groove; 16. Micro servo motor; 17. First gear; 18. Detection groove; 19. Pressure sensor; 20. Pressure... 21. Force plate; 22. Fixing plate; 23. Inlet hole; 24. Wireless laser displacement sensor; 25. Second external gear ring; 26. Limiting groove; 27. Limiting frame; 28. Second gear; 29. ​​Connecting rod; 30. Fixing tube; 31. Rotating groove; 32. Third external gear ring; 33. Movable shell; 34. Eddy current sensor; 35. Spur gear; 36. Miniature drive motor; 37. Buffer shell; 38. Spring; 39. Extension plate; 30. Cleaning brush;

[0055] 201. Serrated structure; 202. Inlet section; 203. First center hole; 204. Positioning hole; 205. Thread tip; 206. Thread root; 301. Second center hole; 302. Positioning pin; 303. Outer circle of head; 304. First fixing hole; 401. Third center hole; 402. Second fixing hole; 501. Fourth center hole; 502. Embossing tool installation; 504. Threaded hole; 505. Connecting hole; 506. Connecting position; 507. Disassembly groove. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] Example: Reference Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 and Figure 10A mold and corrugating method for a coaxial cable spiral metal tube conductor are disclosed. The mold includes a metal tube body 1, with a corrugating assembly on the outside of the metal tube body 1 to improve the corrugating productivity of the coaxial cable spiral metal tube conductor. The corrugating assembly includes a corrugating cutter holder 3, which is disposed outside the metal tube body 1. One end of the corrugating cutter holder 3 has several first fixing holes 304, and the other end of the corrugating cutter holder 3 has several positioning posts 302 fixedly installed. The corrugating cutter holder 3 has a head outer circle 303 on its outside, and one end of the corrugating cutter holder 3 has a second center hole 301. A base body 5 is disposed outside the metal tube body 1, with several connecting holes 505 at one end of the base body 5 and a connecting position 506 at one end of the base body 5. The other end is provided with several threaded holes 504, which correspond to the positions of the first fixing holes 304. One end of the base body 5 is provided with a texturing knife mounting position 502. One end of the texturing knife mounting position 502 is provided with a fourth center hole 501. The texturing knife mounting position 502 is movably engaged with a texturing knife cover 4. One side of the texturing knife cover 4 is provided with several second fixing holes 402, and one side of the texturing knife cover 4 is provided with a third center hole 401. A serrated tungsten steel texturing knife 2 is provided between the texturing knife holder 3 and the texturing knife cover 4. One side of the serrated tungsten steel texturing knife 2 is provided with several positioning holes 204, and one side of the serrated tungsten steel texturing knife 2 is provided with a first center hole 203. The positioning post 302 is movably engaged with the positioning holes 204 and the second fixing holes 402.

[0058] For a 1 / 2" ultra-flexible cable with a characteristic impedance requirement of 50±0.5Ω, the target trough diameter of its spiral copper tube outer conductor after corrugation is 9.6±0.15mm, the target peak diameter is 11.8±0.1mm, and the nominal pitch is 3.0±0.2mm.

[0059] Manufacturing and parameters of each component of the tooling

[0060] Fabrication of the serrated tungsten carbide crimping tool 2:

[0061] Matrix machining: 9SiCr round steel is selected as the blank, and it is initially shaped by turning. The first center hole 203 is machined with a diameter of d1=9.6mm. The preliminary outline of the spiral thread tooth with a total arc length of 540° is machined.

[0062] Heat treatment: The base material is quenched and tempered to achieve an overall hardness of HRC58-60.

[0063] Edge strengthening and finishing: A layer of tungsten carbide, such as YG8, is inlaid on the working surface of the thread through a special brazing process to form a wear-resistant layer. Then, the final shaping grinding is performed on a precision CNC thread grinding machine: the thickness L1 of the shaped section of the thread after grinding is 1.20mm, and the tolerance is controlled within ±0.02mm.

[0064] The thread thickness at the starting end of the feed section 202 is ground to 0.5*L1=0.60mm, and then smoothly transitions linearly to the shaping section, with the transition thread having an arc length of 90°.

[0065] The thread pitch L3 is ground to be 3.0mm + 0.12mm = 3.12mm to compensate for the springback of the copper material.

[0066] The diameter of the infeed arc d2 is machined to 2.2*d1=21.12mm.

[0067] The distance from the top of the infeed to the center distance L2 is machined to 0.5*9.6mm+4.2mm=9.0mm.

[0068] The top of the thread 205 is rounded with a radius R = 0.6 mm; the root of the thread 206 is rounded.

[0069] Serrated teeth processing: Using precision slow wire cutting technology, a uniform serrated structure 201 with a depth of 0.2mm and a length of 2.5mm is processed on the top 205 of the tungsten carbide thread. After processing, the thread is polished again.

[0070] Drilling and polishing: Machining four evenly distributed Φ7.2mm positioning holes 204, and finally deburring and cleaning the tool surface.

[0071] Fabrication of the 3rd grooved tool holder:

[0072] It is machined from 42CrMo alloy steel. The diameter of the second center hole 301 is d3 = crest + 0.6mm = 12.4mm, and the inner wall is ground to a mirror finish.

[0073] Four evenly distributed positioning posts 302 with a diameter of Φ7±0.03mm are machined to form a precise transition fit with the serrated tungsten steel riveting cutter 2 and the positioning hole 204.

[0074] The outer diameter of the head, 303, is the same as the outer diameter of the texturing tool 2.

[0075] Four evenly distributed M8 first fixing holes 304 are machined.

[0076] Making the embossing tool cover 4:

[0077] It is machined from 45 steel, and its outer diameter is the same as that of the embossing tool 2.

[0078] The diameter of the third center hole 401, d4, is equal to the crest plus 2.0 mm, which is 11.80 + 2.0 mm = 13.8 mm. The inner wall is polished.

[0079] Four evenly distributed Φ7.2mm second fixing holes 402 are machined, which are the same as the serrated tungsten steel riveting cutter 2 and the positioning hole 204.

[0080] Construction of base body 5:

[0081] It is machined using 40CrNiMoA forgings.

[0082] The fourth center hole is 501 straight d5 = crest + 0.7 = 11.80 + 0.7 = 12.5mm, the inlet chamfer is 5×45°, the outlet is R1 rounded corner, and the inner wall is ultra-fine ground to a mirror finish.

[0083] The machining grooved tool mounting position 502 has a hole diameter that matches the outer diameter 303 of the tool holder head.

[0084] The connection position 506 and the disassembly groove 507 are for connecting the front-end processing and the main shaft of the rolling mill.

[0085] Machining evenly distributed threaded holes 504 and connecting holes 505.

[0086] II. Assembly of tooling

[0087] Step 1: Insert the serrated tungsten steel embossing cutter 2 into the embossing cutter holder 3, so that the positioning pin 302 is inserted into the positioning hole 204.

[0088] Step 2: Cover the embossing tool cover 4 with the second fixing hole 402 and align it with the positioning post 302.

[0089] Step 3: Place the assembled crimping head module into the crimping cutter mounting position 502 of the base body 5.

[0090] Step 4: Using an internal hex screw, pass it through the base body 5, threaded hole 504, second fixing hole 402 of the cutter cover, serrated tungsten steel embossing cutter 2, and positioning hole 204 in sequence, screw it into the embossing cutter holder 3 and the first fixing hole 304 and tighten it.

[0091] III. Implementation Process of the Corrugation Method

[0092] Step 1, Installation: Install the tooling onto the main shaft of the texturing machine and calibrate its concentricity.

[0093] Step 2, Initial Corrugated Production: Start the traction process. After the forming stabilizes, start welding. After the welding stabilizes, start the corrugating and cooling system. The welded copper tube is intermittently squeezed by the serrated cutting edge through the guide section 202, forming a precisely sized spiral corrugation 102 in the shaping section. At the same time, the insulated core wire is inserted. Online measurement and monitoring show that the trough diameter is stable at 9.6±0.15mm, the peak diameter is stable at 11.8±0.10mm, and the pitch is stable at 3.0±0.2mm. A 20-meter sample is taken, and the characteristic impedance is tested to be 50±0.5Ω. Continuous production is possible.

[0094] Step 3, Tool Rotation and Reuse: After 150 km of continuous production, if the diameter of the detection trough shows an increasing trend, such as reaching 9.73 mm or the characteristic impedance is about to exceed 50±0.5Ω, disassemble the tooling, rotate the serrated tungsten steel crimping tool 2 180° so that the intact feed section 202 on the other side faces forward, reassemble and install it on the machine.

[0095] Fourth, secondary rolling production: using the flipped tool to continue production, the trough size immediately recovers to around 9.6mm, and the characteristic impedance is around 50Ω. This state can be maintained for 130 kilometers.

[0096] After adopting the tooling and method of this implementation:

[0097] Lifespan and Cost: A single set of tooling has produced more than 280 kilometers of high-quality spiral copper tube outer conductor cables, increasing the mold life by more than 5 times.

[0098] Quality and performance: Throughout the entire production process, the characteristic impedance of the cable remains stable at 50±0.4Ω, and the trough is stable at 9.6±0.15mm, which is better than customer requirements. The product consistency has reached a new high, and no process compensation is required.

[0099] Process stability: The serrated structure 201 effectively disperses the rolling force, ensuring stable equipment operation and improving the production environment.

[0100] For a 1-5 / 8" feeder cable used for macro base station signal transmission, the outer conductor is made of copper strip with a thickness of 0.26mm, longitudinally wrapped and welded into a tube and then corrugated. The diameter of the trough after corrugation is 15.0±0.2mm, the diameter of the crest is 17.3±0.25mm, and the nominal pitch is 10.2±0.2mm. Compared with ultra-flexible cables, the cable of this invention is larger in size and longer in pitch, which puts forward higher requirements on the overall rigidity and forming stability of the corrugating tooling, fully demonstrating the scalability and universality of the present invention.

[0101] Based on the above embodiments, refer to Figure 1 , Figure 2 , Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 13 , Figure 14 and Figure 15A movable component for auxiliary conveying of the metal tube body 1 is provided on one side of the connection position 506. The movable component includes an operation slot 6, which is opened on one side of the connection position 506. Several support seats 7 are fixedly installed on one side of the operation slot 6. An operation ring 8 is fixedly installed on one side of the support seats 7. An movable slot 9 is opened on the top surface of the operation ring 8. Several reserved holes 10 are opened on the outer circular wall of the operation ring 8. A first external toothed ring 11 is movably sleeved inside the movable slot 9. An installation ring 12 is fixedly installed at one end of the first external toothed ring 11. Several resistance columns 13 are fixedly installed at one end of the installation ring 12. Several conveying wheels 14 are movably sleeved outside the operation ring 8. Several power slots 15 are opened on the inner circular wall of the conveying wheels 14. The power slots 15 are slidably connected to the resistance columns 13. A micro servo motor 16 is fixedly installed on one side of the operation slot 6. A first gear 17 is fixedly installed at one end of the drive shaft of the micro servo motor 16. The first gear 17 passes through the reserved holes 10 and meshes with the first external toothed ring 11.

[0102] The outer circular wall of the conveyor wheel 14 is provided with several detection grooves 18. A pressure sensor 19 is fixedly installed on one side of the inside of the detection groove 18, and a pressure plate 20 is fixedly installed inside the detection groove 18.

[0103] Before the metal tube enters the corrugating cutter holder 3 and the base body 5, it must first pass through the operating groove 6 to reach the inside of the operating ring 8 via the set conveyor wheel 14. At this time, the metal tube is located between multiple circumferentially distributed conveyor wheels 14. After the system is started, the micro servo motor 16 drives the first gear 17 to rotate. The first gear 17 meshes and drives the first external gear ring 11 to rotate, thereby linking the mounting ring 12 and the resistance column 13 on it to rotate together. When the resistance column 13 moves to the position of the conveyor wheel 14 and slides into the inclined power groove 15 on its back, the groove wall is squeezed. The force is converted into the rotational power of the conveyor wheel 14 around its own axis. This design allows all the conveyor wheels 14 to rotate synchronously towards the center of the operating ring 8 and closely adhere to the surface of the metal tube. With the help of the generated friction, the conveyor wheels 14 can actively and smoothly push the metal tube to the predetermined station in the base body 5 and the embossing cutter holder 3, realizing automatic and precise centering and conveying of the metal tube before it enters the embossing station, replacing manual or passive tube feeding, ensuring high concentricity between the tube and the embossing cutter, laying the foundation for subsequent precision embossing, and improving the degree of automation and feeding stability.

[0104] Each conveyor wheel 14 is equipped with a pressure plate 20 and a pressure sensor 19, which are set up with pressure sensors 19. When the conveyor wheel 14 rotates in contact with the metal tube, the pressure plate 20 contacts the surface of the tube and transmits the pressure to the pressure sensor 19. Theoretically, since the metal tube is positioned at the center by the circumferentially distributed conveyor wheels 14, the pressure values ​​fed back by each sensor should be basically equal. If the reading of a certain sensor is abnormally large or small, it indicates that the metal tube has a center offset or local bulges / depressions in the tube wall. The circumferential and radial pressure distribution on the metal tube during the tube feeding process is monitored in real time. Before the rolling process, the positioning deviation or surface abnormality of the tube can be identified in time, realizing online quality pre-inspection and preventing unqualified products from entering the subsequent process and causing waste or equipment damage.

[0105] Based on the above embodiments, refer to Figure 1 , Figure 9 , Figure 10 , Figure 11 , Figure 16 and Figure 17 A fixing plate 21 is fixedly sleeved inside the operating slot 6. One end of the fixing plate 21 has an inlet hole 22. A wireless laser displacement sensor 23 is provided on the side of the inlet hole 22 near the operating slot 6. A second external gear ring 24 is provided on the side of the fixing plate 21 near the operating slot 6. The wireless laser displacement sensor 23 is fixedly installed with the second external gear ring 24. Two limit frames 26 are fixedly installed on one end of the fixing plate 21. A limit groove 25 is provided on one end of the second external gear ring 24. The limit groove 25 is slidably connected with the limit frame 26. A second gear 27 is provided on one side of the fixing plate 21. The second gear 27 is meshed with the second external gear ring 24. A connecting rod 28 is fixedly installed between the first gear 17 and the second gear 27.

[0106] To ensure the surface quality of the tube before corrugation, a wireless laser displacement sensor 23 is installed behind the inlet hole 22 at the entrance of the operating slot 6. This sensor is not fixed; its base is connected to the second external gear ring 24. When the micro servo motor 16 runs, the power is transmitted through the first gear 17, connecting rod 28, and second gear 27, driving the second external gear ring 24 to rotate. This causes the wireless laser displacement sensor 23 to move in a circular motion around the metal tube, achieving all-round non-contact detection of the outer surface of the metal tube. This overcomes the blind spots of single-point detection, more accurately assesses the overall smoothness and roundness, and makes the detection more comprehensive and efficient.

[0107] Based on the above embodiments, refer to Figure 1 , Figure 18 , Figure 19 , Figure 20 and Figure 21A fixed tube 29 is fixedly installed at one end of the texturing tool holder 3. A rotating groove 30 is opened on the outer circular wall of the fixed tube 29. A third external gear ring 31 is movably sleeved on the inner circular wall of the rotating groove 30. A movable shell 32 is fixedly installed at one end of the third external gear ring 31. An eddy current sensor 33 is fixedly installed on the inner circular wall of the movable shell 32. A spur gear 34 is meshed on the outer circular wall of the third external gear ring 31. A micro drive motor 35 is fixedly installed on the outer circular wall of the fixed tube 29. The drive shaft of the micro drive motor 35 is meshed with the spur gear 34. A buffer shell 36 is fixedly installed on the inner circular wall of the movable shell 32. Several springs 37 are fixedly installed on the inner bottom surface of the buffer shell 36. An extension plate 38 is movably sleeved inside the buffer shell 36. A cleaning brush 39 is fixedly installed on the top surface of the extension plate 38. The extension plate 38 is fixedly installed with the springs 37.

[0108] After the metal tube is rolled, the micro drive motor 35 drives the spur gear 34 to rotate. The spur gear 34 then meshes and drives the third external gear ring 31 to rotate. The third external gear ring 31 drives the movable shell 32 and the eddy current sensor 33 to rotate. Then the eddy current sensor 33 moves along the outer circumference of the metal tube, which facilitates the roughness detection of the rolled metal tube. After the metal tube is rolled, it enters the interior of the movable shell 32. When the movable shell 32 rotates, it drives the buffer shell 36, the extension plate 38 and the cleaning brush 39 to contact the outside of the metal tube, which facilitates the cleaning of the debris remaining on the surface of the rolled metal tube.

[0109] Based on the above embodiments, refer to Figures 1-20 A method for die corrugating a coaxial cable spiral metal tube conductor, the method comprising the following steps:

[0110] Step 1, Installation: Install the tooling onto the corrugating machine spindle that is compatible with 1-5 / 8 inch cables, and finely calibrate the concentricity.

[0111] The second step, initial corrugation production: traction is started, and welding is started after the forming is stable. After the welding is stable, the corrugation and cooling system is started. The welded copper tube is intermittently squeezed by the serrated cutting edge through the inlet section 202, forming a precisely sized spiral corrugation 102 in the shaping section. Online measurement and monitoring show that the trough diameter is stable at 15.0±0.2mm, the crest is stable at 17.3±0.25mm, and the pitch is stable at 10.2±0.2mm, allowing for continuous production.

[0112] The third step is tool flipping and reuse: After 100 kilometers of continuous production, monitoring showed that the diameter of the trough was increasing to 15.0±0.2mm. The machine was stopped, the tooling was disassembled according to the procedure, the serrated tungsten steel embossing tool 2 was flipped 180°, reassembled and installed on the machine.

[0113] Fourth, secondary rolling production: using the flipped tool to continue production, the trough size is restored to around 15.0mm, and production can continue for another 95 kilometers.

[0114] The core feature of the texturing method of this invention lies in the use of a specially designed, double-sided, high-wear-resistant serrated tungsten steel texturing cutter 2 to precisely plastically form a continuously moving metal tube. The main process of this method is as follows: the metal tube 1 is precisely guided and passes through a forming channel composed of a special tooling of this invention; the spiral thread teeth with tungsten steel serrated cutting edges on the texturing cutter are used to perform intermittent, progressive radial extrusion on the tube, thereby efficiently and stably rolling out a geometrically precise and uniform spiral corrugation 102 on its surface; when the working edge of one side of the cutter reaches the wear threshold due to long-term use, especially when the wear of the infeed section 202 is verified, and the wear of the forming section is slight and does not affect the quality, the entire cutter module can be rotated 180° and the new working edge on the other side can be used to continue production, thereby extending the effective service life of the cutter by at least 100%.

[0115] Special tooling

[0116] The specialized tooling for implementing the above method is an integrated precision functional module, which is assembled from four main parts: a serrated tungsten steel embossing knife 2, an embossing knife holder 3, an embossing knife cover 4, and a base body 5. Through synergistic action, it ensures forming accuracy and process stability.

[0117] Core innovative component: Serrated tungsten steel texturing blade 2

[0118] Matrix material and overall heat treatment: The tool matrix is ​​made of low alloy tool steel such as 9SiCr, which has good hardenability and tempering stability. After heat treatment, the hardness reaches HRC56-60, providing solid overall support for complex cutting edges.

[0119] Key Innovation Point A in Cutting Edge Material and Structure: The working surface of the thread tooth, which directly participates in forming, is treated with tungsten carbide inlay. The ultra-high hardness and wear resistance of tungsten carbide fundamentally resist wear and deformation during high-speed rolling. Simultaneously, the thread tooth is designed with a unique serrated structure. This design achieves four main functions:

[0120] ① By converting continuous extrusion into intermittent extrusion, the instantaneous rolling force and radial resistance are significantly reduced, and the processing heat is dispersed;

[0121] ② Suppress periodic vibrations and improve the surface quality of the spiral corrugated pattern;

[0122] ③ Distribute wear across multiple independent serrated edges to delay overall failure;

[0123] ④ Provides a channel for cooling and lubricating media, improving operating conditions.

[0124] Key Design Point B for Reversible Double-Sided Use: The tool adopts a double-sided symmetrical inlet design with a total thread development arc length of 540°. The inlet guide sections 202 at both ends each occupy 90°, and the middle shaping section occupies 360°. Wear is mainly concentrated on the inlet guide section 202. When one end of the guide section 202 wears out, the tool can be flipped to utilize the other end of the new guide section 202. This new guide section 202 can be combined with the original shaping section, which has very little wear, to form a complete new cutting edge sequence that can continue to work with high precision, thus doubling the tool's lifespan.

[0125] Parameters of the serrated tungsten steel crimping cutter: The center bore diameter d1 of the cutter is precisely equal to the target trough diameter; the distance from the top of the thread inlet to the center position L2 = 0.5*d1 + 4-4.5mm; the arc length diameter d2 at the inlet is designed to be 2-2.5*d1 to ensure smooth pipe feeding; the thread thickness at the inlet is designed to be 0.5*L1; the thickness of the shaped thread L1 is strictly controlled within ±0.02mm; the thread thickness at the inlet and the shaped thread thickness are linearly thickened for a smooth transition; the thread pitch L3 is the nominal pitch of the cable plus 0.1-0.5mm; all cutting edge roots are rounded, and the top is rounded with the same diameter as the thread thickness; the serrations on the thread are evenly distributed with a length of 2-3mm.

[0126] Support and mounting components

[0127] The texturing tool holder 3 and the texturing tool cover 4 together form a clamping unit for precise positioning, clamping, and protection of the serrated tungsten steel texturing tool 2. The diameter of the central guide hole d3 of the texturing tool holder 3 is slightly larger than that of the tube, which is equal to the crest diameter + 0.5-1.0 mm. The inner wall is mirror-polished to ensure that the metal tube passes through without resistance or scratches. The diameter of the central guide hole d4 of the texturing tool cover 4 is equal to the crest diameter + 1.5-3 mm. The texturing tool holder 3 is equipped with a fixing post that precisely matches the positioning hole 204 and is connected to the base body 5 through screw holes.

[0128] Base Body 5: Serving as the mounting base and equipment interface for the entire tooling, its core functions include:

[0129] It provides mounting interfaces such as circular steps and square slots that match the spindle of the texturing equipment; it has a precision-machined center guide hole with a diameter d5 = crest diameter + 0.6-1.1mm, and the inlet is chamfered and the outlet is rounded and mirror-polished to achieve ultimate centering and guidance from the equipment to the forming area; it provides a stable rigid support for the entire texturing head module through evenly distributed recessed screw holes.

[0130] Working principle: Please refer to Figures 1-21As shown, before the metal tube enters the interior of the crimping cutter holder 3 and the base body 5 via the set conveyor rollers 14, the metal tube first reaches the interior of the operating groove 6, and then moves to the interior of the operating ring 8. At this time, the metal tube is between several conveyor rollers 14. Then, by using the micro servo motor 16, the drive shaft of the micro servo motor 16 rotates, which drives the first gear 17 to rotate. When the first gear 17 rotates, it meshes with the first external gear ring 11, causing the first external gear ring 11 to rotate. The rotation of the first external gear ring 11 drives the mounting ring 12 and the resistance column 13 to rotate. Then the resistance column 1... 3 will move to the position of the conveyor wheel 14 and enter the interior of the power groove 15. Since the power groove 15 has an inclined angle, when the resistance column 13 enters the interior of the power groove 15 and moves along the inner wall of the power groove 15, the resistance column 13 squeezes the inner wall of the power groove 15, which can make the conveyor wheel 14 rotate. Then, several conveyor wheels 14 will rotate simultaneously towards the center point of the operating ring 8, and the conveyor wheel 14 will rotate against the metal tube. Through the friction generated when the conveyor wheel 14 contacts the metal tube, the metal tube can be moved to send the metal tube into the interior of the base body 5 and the crimping cutter holder 3.

[0131] By using the pressure sensor 19, when the conveyor wheel 14 rotates on the surface of the metal tube, the contact between the conveyor wheel 14 and the metal tube generates an interaction force. As the conveyor wheel 14 continues to rotate, the pressure plate 20 will come into contact with the surface of the metal tube. After being squeezed, the pressure plate 20 will continue to squeeze the pressure sensor 19. Through the sensing of the pressure sensor 19, the pressure at the contact position between the metal tube and multiple conveyor wheels 14 can be detected. Since the metal tube is located at the center position among several conveyor wheels 14, and the conveyor wheels 14 are evenly arranged in a circle around the outside of the metal tube, under normal circumstances, the pressure on several conveyor wheels 14 is the same. When the pressure sensor 19 installed on one of the conveyor wheels 14 shows that the pressure is too high or too low, it indicates that the position of the metal tube has shifted or that there are protrusions on the outside of the metal tube, thus making it easier to eliminate problems with the metal tube before the metal tube is rolled.

[0132] The metal tube passes through the inlet hole 22 and enters the operating groove 6 via the wireless laser displacement sensor 23. At this time, the staff can scan the outside of the metal tube by using the wireless laser displacement sensor 23, which makes it easier to detect the smoothness of the outside of the metal tube.

[0133] When the drive shaft of the micro servo motor 16 rotates via the second external gear ring 24, it will drive the connecting rod 28 and the second gear 27 to rotate via the first gear 17. In turn, the second gear 27 will mesh and drive the second external gear ring 24 to rotate. Then, the second external gear ring 24 will drive the wireless laser displacement sensor 23 to move in a circular motion on the surface of the metal tube, thereby making it easier to change the detection position of the wireless laser displacement sensor 23 on the metal tube.

[0134] With the eddy current sensor 33 in place, after the metal tube is rolled, the drive shaft of the micro drive motor 35 rotates, which drives the spur gear 34 to rotate. The spur gear 34 then meshes and drives the third external gear ring 31 to rotate. The third external gear ring 31 drives the movable shell 32 and the eddy current sensor 33 to rotate. Then the eddy current sensor 33 moves along the outer circumference of the metal tube, which facilitates the roughness detection of the rolled metal tube.

[0135] The cleaning brush 39 is installed so that when the metal tube is rolled, it enters the interior of the movable shell 32. When the movable shell 32 rotates, it will drive the buffer shell 36, the extension plate 38 and the cleaning brush 39 to contact the outside of the metal tube, thereby facilitating the cleaning of the debris remaining on the surface of the rolled metal tube.

[0136] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mold for a coaxial cable spiral metal tube conductor, characterized in that, include: Metal tube body (1); A corrugating assembly is disposed outside the metal tube body (1) to improve the corrugating productivity of coaxial cable spiral metal tube conductors. The corrugating assembly includes: a corrugating cutter holder (3), which is disposed outside the metal tube body (1). The corrugating cutter holder (3) has a head outer circle (303) on its outer side. A second center hole (301) is opened at one end of the corrugating cutter holder (3). A base body (5) is disposed outside the metal tube body (1). A connection position (506) is opened at one end of the base body (5). A corrugating cutter mounting position (502) is opened at one end of the base body (5). A fourth center hole is opened at one end of the corrugating cutter mounting position (502). The grooved tool mounting position (502) is internally and movably connected to the grooved tool cover (4). Several second fixing holes (402) are opened on one side of the grooved tool cover (4). A third center hole (401) is opened on one side of the grooved tool cover (4). A serrated tungsten steel grooved tool (2) is provided between the grooved tool holder (3) and the grooved tool cover (4). The serrated tungsten steel grooved tool (2) is made of low alloy tool steel with good hardenability and tempering stability. It has a tungsten steel serrated cutting edge and the cutting edge is a spiral thread. The thread has a unique serrated structure. The working surface of the thread is inlaid with a layer of tungsten steel (hard alloy, such as YG8) through a special brazing process to form a wear-resistant layer. A movable component for auxiliary conveying of the metal tube body (1) is provided on one side of the connection position (506).

2. The mold for a coaxial cable spiral metal tube conductor according to claim 1, characterized in that, The moving component includes: An operating groove (6) is formed on one side inside the connection position (506). Several support seats (7) are fixedly installed on one side inside the operating groove (6). An operating ring (8) is fixedly installed on one side of each of the support seats (7). A movable groove (9) is formed on the top surface of the operating ring (8). Several reserved holes (10) are formed on the outer circular wall of the operating ring (8). A first external toothed ring (11) is movably sleeved inside the movable groove (9). An installation ring (12) is fixedly installed at one end of the first external toothed ring (11). The installation ring (12) is... One end of the operating ring (8) is fixedly installed with several resistance columns (13), and several conveying wheels (14) are movably sleeved on the outside of the operating ring (8). Several power grooves (15) are opened on the inner circular wall of the conveying wheel (14). The power grooves (15) are slidably connected to the resistance columns (13). A micro servo motor (16) is fixedly installed on one side of the operating groove (6). A first gear (17) is fixedly installed on one end of the drive shaft of the micro servo motor (16). The first gear (17) passes through the reserved hole (10) and meshes with the first external gear ring (11).

3. The mold for a coaxial cable spiral metal tube conductor according to claim 2, characterized in that: The outer circular wall of the conveyor wheel (14) is provided with a number of detection grooves (18). A pressure sensor (19) is fixedly installed on one side of the inside of the detection groove (18), and a pressure plate (20) is fixedly installed inside the detection groove (18).

4. The mold for a coaxial cable spiral metal tube conductor according to claim 2, characterized in that: A fixing plate (21) is fixedly sleeved inside the operating slot (6). One end of the fixing plate (21) is provided with an inlet hole (22). A wireless laser displacement sensor (23) is provided on the side of the inlet hole (22) near the operating slot (6).

5. The mold for a coaxial cable spiral metal tube conductor according to claim 4, characterized in that: A second external gear ring (24) is provided on the side of the fixed plate (21) near the operating groove (6). The wireless laser displacement sensor (23) is fixedly installed with the second external gear ring (24). Two limit frames (26) are fixedly installed on one end of the fixed plate (21). A limit groove (25) is opened on one end of the second external gear ring (24). The limit groove (25) is slidably connected with the limit frame (26). A second gear (27) is provided on one side of the fixed plate (21). The second gear (27) is meshed with the second external gear ring (24). A connecting rod (28) is fixedly installed between the first gear (17) and the second gear (27).

6. The mold for a coaxial cable spiral metal tube conductor according to claim 1, characterized in that: A fixed tube (29) is fixedly installed at one end of the embossing tool holder (3). A rotating groove (30) is opened on the outer circular wall of the fixed tube (29). A third external gear ring (31) is movably sleeved on the inner circular wall of the rotating groove (30). A movable shell (32) is fixedly installed at one end of the third external gear ring (31). An eddy current sensor (33) is fixedly installed on the inner circular wall of the movable shell (32). A spur gear (34) is meshed on the outer circular wall of the third external gear ring (31). A micro drive motor (35) is fixedly installed on the outer circular wall of the fixed tube (29). The drive shaft of the micro drive motor (35) is meshed with the spur gear (34).

7. The mold for a coaxial cable spiral metal tube conductor according to claim 6, characterized in that: A buffer shell (36) is fixedly installed on the inner circular wall of the movable shell (32). Several springs (37) are fixedly installed on the inner bottom surface of the buffer shell (36). An extension plate (38) is movably sleeved inside the buffer shell (36). A cleaning brush (39) is fixedly installed on the top surface of the extension plate (38). The extension plate (38) and the springs (37) are fixedly installed.

8. A method for die-rolling a coaxial cable spiral metal tube conductor, and a die for a coaxial cable spiral metal tube conductor as described in any one of claims 1-7, characterized in that, This method Includes the following steps: Step 1, Installation: Install the tooling onto the spindle of the twill mill that is compatible with 1-5 / 8 inch cables, and finely correct the concentricity. Meanwhile, the base of the serrated tungsten steel twill mill cutter (2) is made of low alloy tool steel (such as 9SiCr) with good hardenability and tempering stability. After heat treatment, the hardness reaches HRC56-60, providing solid overall support for complex cutting edges. Parameters of serrated tungsten steel grommets (2): The center hole diameter d1 of the tool is exactly equal to the target trough diameter. The distance from the top of the thread inlet to the center position is L2 = 0.5*d1 + (4-4.5) mm. The arc length diameter d2 at the inlet is designed to be (2-2.5)*d1 to ensure smooth pipe feeding. The thread thickness at the inlet is designed to be 0.5*L1. The thickness of the shaped thread L1 is strictly controlled within ±0.02 mm. The thread thickness at the inlet and the shaped thread thickness are linearly thickened and smoothly transitioned. The thread pitch L3 is the nominal pitch of the cable plus 0.1-0.5 mm. All cutting edges are rounded at the root and rounded at the top. The rounded corner diameter is the same as the thread thickness. The serrations on the thread are evenly distributed with a length of 2-3 mm and are required to be evenly distributed. The second step is the first roll forming production: start traction, start welding after the forming is stable, start the roll forming and cooling system after the welding is stable, and the welded copper tube is intermittently squeezed by the sawtooth cutting edge through the inlet section (202) to form a spiral corrugation (102) with precise dimensions in the shaping section. The diameter of the trough is stabilized at 15.0±0.2mm, the peak is stabilized at 17.3±0.25mm, and the pitch is stabilized at 10.2±0.2mm, which can be used for continuous production. The third step is to flip and reuse the serrated tungsten carbide embossing cutter (2): After continuous production for 100 kilometers, the monitoring found that the diameter of the trough tended to increase to 15.0±0.2mm and the machine was stopped. The tooling was disassembled according to the procedure, and the serrated tungsten carbide embossing cutter (2) was flipped 180°. The serrated tungsten carbide embossing cutter (2) adopts a double-sided symmetrical inlet design. After reassembly, it was installed on the machine. Fourth, secondary rolling production: using the flipped tool to continue production, the trough size is restored to around 15.0mm, and production can continue for another 95 kilometers.

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