Process and device for steel billet punching and drawing and large-diameter bottle blank cold-drawing composite forming

Abstract

The invention relates to the technical field of metal pressure processing, in particular to a process and device for cold-drawing composite forming of a large-diameter bottle blank through billet punching and drawing, and the device comprises a base, a pushing mechanism, a cold-drawing device, a feeding mechanism, a conveying mechanism, a dismounting mechanism, a supporting mechanism, a demolding mechanism and four supporting columns. By arranging the feeding mechanism, after an infrared sensor detects a bottle blank body on a transverse plate, a first driving motor is started, a threaded rod is driven to rotate through a first rotating shaft, a movable frame slides to the position between two semi-arc bases along a sliding rod, and then a second electric push rod extends to push a semi-arc supporting plate to be parallel to the semi-arc bases; then a hydraulic cylinder drives a hydraulic rod to descend, then a T-shaped block drives a push plate to be located at the bottle blank body fed at the starting end, a feeding plate is located at the bottle blank body fed forwards at the tail end, then a first electric push rod extends, and the push plate pushes the bottle blank body fed at the starting end into two semi-arc seats.

Description

A process and apparatus for combined forming of large-diameter bottle preforms by punching and drawing steel billets. Technical Field

[0001] This invention relates to the field of metal pressure processing, and in particular to a process and apparatus for the combined forming of large-diameter bottle preforms by punching steel billets. Background Technology

[0002] Currently, three forming processes are used to manufacture steel cylinder preforms: billet stamping and drawing, steel pipe bottom forming, and steel plate stretching. The billet stamping and drawing process uses steel billets, ingots, or bars as raw materials, which are heated, extruded, and stretched. The steel pipe bottom forming process uses seamless steel pipes as raw materials, which are heated and formed at the bottom. The steel plate stretching process uses steel plates as raw materials, which are stretched.

[0003] Existing cold-drawing processes primarily use steel tube bottom-forming techniques to manufacture small-diameter, low-strength preforms, and the raw material is always transported manually. However, preforms manufactured using the stamping process for large-diameter (Φ219mm and above) and high-strength (tensile strength of 1100MPa and above) steel billets exhibit significant wall thickness deviations and heavy cylinder weights during hot stamping, along with numerous small defects on both the inner and outer surfaces, posing a greater risk to safe use. Therefore, appropriate reprocessing methods must be employed to ensure uniform wall thickness deviations in stamped preforms made from high-strength materials, achieving weight reduction and eliminating surface defects to ensure safe use. Furthermore, for these large-diameter, heavy preforms, the processing procedure requires addressing issues of intelligent operation and efficiency. Summary of the Invention

[0004] The purpose of this application is to provide a process and apparatus for the cold drawing composite forming of large-diameter bottle preforms from steel billets, to solve the technical problems of hot drawing large-diameter bottle preforms from high-strength steel billets: the difficulty in cold working deformation of high-strength bottle preforms; the large wall thickness deviation and poor lightweighting of bottle preforms from hot drawing steel billets; and the numerous small defects on the inner and outer surfaces of hot-drawn steel billets. This aims to achieve cold working of high-strength materials, resulting in uniform and lightweight bottle preforms with defect-free inner and outer surfaces.

[0005] This application provides a process for cold drawing composite forming of large-diameter bottle preforms from steel billets, employing the following technical solution: S1: Billet preparation: Using standard-sized square billets, sawing the billets according to the set cutting weight, designing the diagonals according to process requirements, the radius (R) according to standard dimensions, and designing the inner dimensions of the lower die according to fitting requirements. At a specific heating temperature, based on the thermal expansion coefficient of steel, the diagonals of the billet will experience corresponding thermal expansion. That is, when the billet is vertically pressed at this heating temperature, the diagonal dimensions change to a specific value due to thermal expansion. When matched with the lower die dimensions, this ensures that the billet can smoothly enter the lower die and that the gap between the billet and the lower die is controlled within the allowable range; S2: Billet heating: Heating the square billet to the process temperature... Set the temperature and maintain it for a specified time to ensure consistent temperature inside and outside the billet, ensuring that metal flow during stamping and hot drawing does not cause uneven wall thickness due to temperature deviation; S3: Through-hole: During stamping and drawing, a floating beam lower end positioning and clamping centering technology is adopted to ensure that the punch and lower die are always at the axisymmetric center during the entire reverse extrusion process, ensuring the uniformity of the stamped bottle blank skin thickness from the perspective of die reliability. The vertically pressed punched blank undergoes multiple round die extrusions in a specific temperature range, and then undergoes multiple rounds of cross-staggered covering rolling die rolling, finally forming a drawn bottle blank with inner and outer diameters meeting the design tolerance requirements. When passing through the overall round die, the punched blank undergoes multiple consecutive drawing passes, the overall outer diameter decreases, the wall thickness decreases, and the corresponding wall thickness deviation... It also reduces the thickness of the wall while the cross-staggered rolling die is designed. Each pass is staggered at a set angle, which not only finishes the outer surface but also ensures uniform wall thickness. S4: Preform Annealing: The preform is annealed at the set temperature to eliminate uneven hardness after hot drawing and to control the overall hardness of the preform within a suitable range for subsequent processing, facilitating metal deformation during cold drawing. S5: Preform Internal and External Polishing: The oxide scale on the annealed preform is polished clean to create favorable conditions for subsequent phosphating, saponification, and drawing processes. S6: Preform Phosphating and Saponification: The annealed preform undergoes phosphating and saponification to form a saponification layer on its surface, ensuring lubrication of the metal flow during drawing. S7: Preform Cold Drawing: During cold drawing, the power station moves towards... The main hydraulic cylinder supplies oil, causing it to advance along the guide rail. The piston rod inside the main hydraulic cylinder pushes the extrusion rod, which, supported by the support mechanism, advances to the rear of the conveying mechanism and stops. The feeding mechanism transports the preform to the front of the extrusion rod. The extrusion rod advances, causing the preform to fit onto the extrusion rod. The feeding mechanism then withdraws, and the extrusion rod continues to advance with the preform through the cold drawing device. The horizontal plate and rough pad support the preform portion that has not entered the cold drawing device, while the demolding plate supports the preform portion that has entered the cold drawing device. The drawing die inside the cold drawing device deforms the preform. After drawing is complete, the demolding mechanism separates the preform from the extrusion rod. The drawn preform rolls along the demolding plate onto the conveying mechanism. After completion, the main hydraulic cylinder returns to its original position with the extrusion rod. During this process, the filling valve is used for rapid oil discharge during the return stroke of the main hydraulic cylinder.S8: Bottle Preform Cutting: Irregular excess material or burrs caused by deformation at both ends of the cold-drawn bottle preform necessitates a cutting process. First, the cold-drawn preform is fixed to a specialized fixture. Then, high-precision cutting equipment is used to cut both ends of the preform according to the design dimensions. During cutting, an infrared positioning device ensures the cut is perpendicular to the preform's axis, with deviations controlled within acceptable limits. After cutting, a grinding wheel is used to polish the cut edges, removing burrs and flash to ensure a smooth transition and prevent stress concentration or scratches caused by sharp edges in subsequent processes. Simultaneously, the length of the preform after cutting is checked to ensure it meets the dimensional requirements of the next process, with tolerances controlled within specified limits. High-strength material-based punched preforms can achieve cold deformation. The processing method avoids surface cracking defects, reduces wall thickness deviation, and achieves uniform wall thickness. The quality of the preform is lower than that of similar preforms manufactured using the steel billet stamping process, achieving lightweighting, material savings, and carbon reduction goals. Minor defects on the inner and outer surfaces, such as oxide pits, wire drawing, or ridges, are completely eliminated during cold drawing deformation, achieving a defect-free surface and improving the safety performance of the cylinder. The second cold drawing deformation process makes the material structure denser, improving the material properties of the cylinder and further enhancing its safe use. A matching cold-drawing mandrel structure is designed to address the complex concave bottom structure of the hot-stamped preform, resulting in a preform bottom structure with good fatigue performance. Digital control technology ensures stable preform quality, high pass rate, and high production efficiency after cold drawing.

[0006] This application also provides a device for cold drawing composite forming of large-diameter bottle preforms from steel billets. Based on the aforementioned process for cold drawing composite forming of large-diameter bottle preforms from steel billets, it includes a base, a pushing mechanism, a cold drawing device, a feeding mechanism, a transport mechanism, a disassembly mechanism, a support mechanism, a demolding mechanism, and four support columns. The feeding mechanism includes a horizontal plate fixedly connected to the top of the four support columns. Two limiting plates are fixedly connected to the top of the horizontal plate. Support frames are fixedly connected to the sides of the two limiting plates. A hydraulic cylinder is fixedly installed on the top of the support frame. A hydraulic rod is fixedly installed inside the hydraulic cylinder. A T-shaped block is fixedly connected to the bottom of the hydraulic rod. A first electric push rod is fixedly installed on the side of the T-shaped block. A push plate is fixedly connected to one end of the first electric push rod. A feeding plate is fixedly connected to the side of the push plate. Several feeding plates are placed on the top of the horizontal plate. The preform body has an infrared sensor installed on the top of the support frame. A fixed box is fixedly connected to the bottom of the horizontal plate. A first drive motor is fixedly installed on the side of the fixed box via an mounting plate. First bearings are fixedly connected to both sides of the inner wall of the fixed box. A first rotating shaft is rotatably connected inside each of the two first bearings. One end of one of the first rotating shafts is fixedly connected to the output shaft of the first drive motor. A threaded rod is fixedly connected to one end of each of the two first rotating shafts. A movable frame is threadedly connected to the surface of the threaded rod. A second electric push rod is fixedly installed on the top of the movable frame. A semi-circular support plate is fixedly connected to the top of the second electric push rod. Two semi-circular seats are fixedly connected to the side of the horizontal plate. A rough pad is provided on the top of the horizontal plate. Two sliding rods are fixedly connected to the inner wall of the fixed box. The movable frame is slidably connected to the surface of the sliding rods.

[0007] By adopting the above technical solution and setting up a feeding mechanism, after the infrared sensor detects the preform body on the horizontal plate, the first drive motor starts, and drives the threaded rod to rotate through the first rotating shaft, causing the moving frame to slide along the slide bar between the two semi-circular seats. Then, the second electric push rod extends and pushes the semi-circular support plate parallel to the semi-circular seats. Subsequently, the hydraulic cylinder drives the hydraulic rod to descend, thereby causing the T-shaped block to move the push plate to the preform body at the beginning of the feeding, while the feeding plate is located at the preform body at the end of the feeding. Then, the first electric push rod extends, the push plate pushes the preform body at the beginning of the feeding into the two semi-circular seats, and the feeding plate pushes the preform body at the end of the feeding to the front. Finally, the moving frame and the semi-circular support plate transport the preform body to the extrusion rod, achieving the purpose of replacing manual feeding. The effect of automated operation is achieved through infrared sensing and mechanical linkage, while avoiding the safety hazards caused by manual contact. By setting a rough pad, the friction is increased to prevent the preform body from sliding.

[0008] Preferably, the pushing mechanism includes a fixed plate fixedly connected to the top of the base, a main hydraulic cylinder fixedly mounted on the side of the fixed plate, a piston rod fixedly mounted inside the main hydraulic cylinder, a support seat fixedly connected to the surface of the main hydraulic cylinder, and three prestressed supports fixedly connected to the interior of the fixed plate and the interior of the cold drawing device. By adopting the above technical solution, by setting the pushing mechanism, the main hydraulic cylinder can drive the piston rod to extend and retract forward, thereby providing extrusion power for subsequent applications. By setting the support seat, the stability of the main hydraulic cylinder is enhanced. By setting the prestressed supports, the reverse force generated during cold drawing is counteracted, ensuring the relative position of the fixed plate and the cold drawing device remains stable.

[0009] Preferably, a cold-drawing device is fixedly installed on the top of the base, a support platform is fixedly connected to the top of the fixing plate, a power station is fixedly installed on the top of the support platform, a filling valve is provided on the top of the main oil cylinder, an oil supply pipe is fixedly connected inside the filling valve, and the other end of the oil supply pipe is fixedly connected inside the power station. A railing is fixedly connected to the top of the support platform, four support legs are fixedly connected to the bottom of the support platform, a support frame is fixedly connected to the side of the base, four fastening seats are fixedly connected to the top of the support frame, two handles are fixedly connected to the side of the railing, a staircase is fixedly connected to the side of the support platform, and four support columns are fixedly connected to the top of the base. By adopting the above technical solution... By setting up a cold drawing device, the preform body can be cold drawn. By setting up a support platform, the installation space for the power station can be provided. By setting up a power station, a filling valve and an oil supply pipe, the power station can supply oil to the main oil cylinder through the oil supply pipe. The filling valve can easily control the oil supply flow, thus providing power to the extrusion rod. By setting up a fence, the maintenance personnel can be protected. By setting up support legs, the power station can be rigidly supported. By setting up a support frame and a fastening seat, the transportation mechanism can be stably supported. By setting up handles and stairs, the maintenance personnel can easily climb. By setting up support columns, the feeding mechanism can be rigidly supported.

[0010] Preferably, the transport mechanism includes two elongated plates fixedly connected to the top of four fastening seats. A second drive motor is fixedly mounted on the side of one of the elongated plates, and four second bearings are fixedly connected to the sides of the two elongated plates. A second rotating shaft is rotatably connected inside each of the two sets of second bearings. One end of one of the second rotating shafts is fixedly connected to the output shaft of the second drive motor. Pulleys are fixedly connected to the surfaces of both second rotating shafts. A rubber belt is driven between the two pulleys, and a conveyor belt is driven between the two second rotating shafts. By adopting the above technical solution and setting up the transport mechanism, the cold-drawn preform body can be rolled onto the conveyor belt via the demolding template. Subsequently, the second drive motor drives the pulleys to rotate through the second rotating shafts, thereby causing the rubber belt to drive the conveyor belt to operate, transporting the preform body to the next process. This structure prevents scratches on the surface of the preform body, and the conveyor belt speed is synchronized with the cold drawing rhythm, achieving continuous production and reducing collision damage caused by preform body accumulation.

[0011] Preferably, the disassembly mechanism includes a connecting seat fixedly connected to one end of the piston rod. A screw is threaded into the internal part of the connecting seat, and a pressing rod is threaded into the surface of the screw. A guide rail is fixedly connected to the side of the fixing plate and the side of the cold drawing device. A slider is slidably connected inside the guide rail, and the side of the slider is fixedly connected to the surface of the connecting seat. By adopting the above technical solution and setting up the disassembly mechanism, when the pressing rod needs to be replaced, the old pressing rod can be removed by unscrewing the screw on the connecting seat. After replacing the new pressing rod, the screw is tightened again for fixation, and the slider will slide along the guide rail, ensuring the coaxiality of the pressing rod and the piston rod. The screw connection method of this structure improves the tightness of the pressing rod, while the cooperation between the guide rail and the slider ensures stable movement of the pressing rod, improving the versatility of the equipment.

[0012] Preferably, the support mechanism includes a fixed frame fixedly connected to the top of the base, a third electric push rod fixedly installed at the bottom of the fixed frame, a lifting plate fixedly connected to the top of the third electric push rod, and the pressing rod overlapping the top of the lifting plate. By adopting the above technical solution and setting the support mechanism, the third electric push rod can push the lifting plate to the surface of the pressing rod, thereby achieving the purpose of providing auxiliary support for the pressing rod.

[0013] Preferably, the demolding mechanism includes a horizontal block and a demolding plate fixedly connected to the side of the cold drawing device. A fourth electric push rod is fixedly installed on the top of the horizontal block, and a clamping plate is fixedly connected to the bottom end of the fourth electric push rod. Rubber pads are provided on the surfaces of both the clamping plate and the demolding plate. By adopting the above technical solution and setting the demolding mechanism, after cold drawing, the fourth electric push rod extends to push the clamping plate down, cooperating with the demolding plate to clamp the preform body. Subsequently, the extrusion rod returns under the drive of the main hydraulic cylinder, and the preform body separates from the extrusion rod under the action of clamping force, achieving the purpose of convenient release of the preform body. By setting the rubber pads, damage to the surface of the preform body is avoided during clamping. Beneficial effects

[0014] In summary, this application includes at least one of the following beneficial technical effects: By setting up a feeding mechanism, after the infrared sensor detects the preform body on the horizontal plate, the first drive motor starts, driving the threaded rod to rotate through the first rotating shaft, causing the moving frame to slide along the slide bar between the two semi-circular seats. Then, the second electric push rod extends to push the semi-circular support plate parallel to the semi-circular seats. Subsequently, the hydraulic cylinder drives the hydraulic rod to descend, thereby causing the T-shaped block to move the push plate to the preform body at the beginning of the feeding, while the feeding plate is located at the preform body at the end of the feeding. Then, the first electric push rod extends, the push plate pushes the preform body at the beginning of the feeding into the two semi-circular seats, and the feeding plate pushes the preform body at the end of the feeding to the front. Finally, the moving frame and the semi-circular support plate transport the preform body to the extrusion rod, achieving the purpose of replacing manual feeding. The effect of automated operation is achieved through infrared sensing and mechanical linkage, while avoiding the safety hazards caused by manual contact. By setting a rough pad, friction is increased to prevent the preform from sliding. The high-strength material used in the cold-drawn preform allows for cold deformation without surface cracking, reducing wall thickness deviation and achieving uniform wall thickness. The preform quality is lower than that of similar preforms manufactured by steel billet drawing, achieving lightweighting, saving materials and meeting carbon reduction targets. Small defects on the inner and outer surfaces, such as oxide pits, wire drawing, or ridges, are completely eliminated during the cold-drawing deformation process, achieving a defect-free surface and improving the safety performance of the cylinder. The preform undergoes a second cold deformation process, making the material structure denser and improving the material properties of the cylinder, which is more conducive to safe use. A matching cold-drawing mandrel structure is designed for the complex concave bottom structure of the hot-drawn preform, resulting in a preform bottom structure with good fatigue performance. The intelligent control technology ensures stable quality, high pass rate, and high production efficiency of the cold-drawn preform. Attached Figure Description

[0015] Figure 1 is a schematic diagram of the overall front view of the present invention; Figure 2 is a schematic diagram of the overall side view of the present invention; Figure 3 is a schematic diagram of the front view of the pushing mechanism in the present invention; Figure 4 is a schematic diagram of the side view of the feeding mechanism in the present invention; Figure 5 is a schematic diagram of the bottom view of the feeding mechanism in the present invention; Figure 6 is a schematic diagram of the bottom view of a portion of the feeding mechanism in the present invention; Figure 7 is a schematic diagram of the side view of the transport mechanism in the present invention; Figure 8 is an enlarged schematic diagram of point A in Figure 7.

[0016] The components include: 1. Base; 2. Pushing mechanism; 201. Fixing plate; 202. Main hydraulic cylinder; 203. Piston rod; 3. Cold drawing device; 4. Feeding mechanism; 401. Horizontal plate; 402. Limiting plate; 403. Support frame; 404. Hydraulic cylinder; 405. Hydraulic rod; 406. T-block; 407. First electric push rod; 408. Push plate; 409. Feeding plate; 410. Bottle preform body; 411. Infrared sensor; 412. Fixing box; 413. Moving frame; 414. Second electric push rod; 415. Semi-arc support plate; 416. Semi-arc seat; 417. First drive motor; 418. First bearing; 419. First rotating shaft; 420. Threaded rod; 5. Support platform; 6. Power station; 7. Transportation mechanism; 701. Long plate; 702. Second drive motor. 703. Second bearing; 704. Second shaft; 705. Rubber belt; 706. Conveyor belt; 707. Pulley; 8. Disassembly mechanism; 801. Connecting seat; 802. Screw; 803. Extrusion rod; 9. Support mechanism; 901. Fixing frame; 902. Third electric push rod; 903. Lifting plate; 10. Demolding mechanism; 1001. Horizontal block; 1002. Fourth electric push rod; 1003. Clamping plate; 1004. Demolding template; 1005. Rubber pad; 11. Fence; 12. Support leg; 13. Support seat; 14. Support frame; 15. Fastening seat; 16. Handle; 17. Staircase; 18. Prestressed support column; 19. Guide rail; 20. Slider; 21. Oil supply pipe; 22. Filling valve; 23. Rough pad; 24. Support column; 25. Slide rod. Detailed Implementation

[0017] The present application will be further described in detail below with reference to Figures 1-8.

[0018] Example 1: A process for cold drawing composite forming of large-diameter bottle preforms from steel billets, comprising the following steps: S1: Billet preparation: Using standard-sized square billets, sawing the billets according to the set cutting weight, designing the diagonals according to process requirements, designing the radius (R) according to standard dimensions, and designing the inner dimensions of the lower die according to fitting requirements. At a specific heating temperature, the diagonals of the square billet will generate a corresponding amount of thermal expansion according to the coefficient of thermal expansion of steel. That is, when the billet is vertically pressed at this heating temperature, the diagonal dimension changes to a specific value due to thermal expansion, which is related to the lower die. When dimensionally matching, it ensures that the billet can smoothly enter the lower die and that the gap between the billet and the lower die is controlled within the allowable range; S2: Billet heating: The billet is heated to the process-set temperature and held at that temperature for a specified time to ensure that the temperature inside and outside the billet is consistent, ensuring that the metal flow during stamping and hot drawing does not cause uneven wall thickness due to temperature deviation; S3: Through-hole: During stamping and drawing, a floating beam lower end positioning and clamping centering technology is used to ensure that during the vertical pressing process, the punch and the lower die are always at the axisymmetric center throughout the entire reverse extrusion process. To ensure the uniformity of the sheet thickness of the stamped bottle preform from the perspective of mold reliability, the vertically pressed punched preform undergoes multiple rounds of ring die extrusion within a specific temperature range, followed by multiple rounds of cross-staggered covering rolling die rolling, ultimately forming a drawn bottle preform with inner and outer diameters meeting design tolerance requirements. During the overall ring die rolling, the punched preform undergoes multiple consecutive drawing passes, reducing the overall outer diameter and wall thickness, and correspondingly reducing wall thickness deviation. In the cross-staggered rolling die design, each pass is staggered at a set angle, which, while finishing the outer surface, also contributes to uniform wall thickness. 4. Preform Annealing: Anneal the preform at the set temperature to eliminate uneven hardness after hot drawing and control the overall hardness of the preform within a suitable range for subsequent processing, facilitating metal deformation during cold drawing; S5. Preform Internal and External Polishing: Polish the oxide scale off the annealed preform to create favorable conditions for subsequent phosphating, saponification, and drawing processes; S6. Preform Phosphating and Saponification: Treat the annealed preform with phosphating and saponification to form a saponification layer on its surface, ensuring lubrication for metal flow during drawing;S7: Preform Cold Drawing: During cold drawing, power station 6 supplies oil to main cylinder 202, causing main cylinder 202 to advance along guide rail 19. Piston rod 203 inside main cylinder 202 pushes extrusion rod 803. Extrusion rod 803 advances to the rear of conveying mechanism under the support of support mechanism 9 and stops. Feeding mechanism 4 conveys preform to the front of extrusion rod 803. Extrusion rod 803 advances to make preform fit over extrusion rod 803. Feeding mechanism 4 withdraws. Extrusion rod 803 continues to advance with preform through cold drawing device 3. Horizontal plate 401 and rough pad 23 support the preform portion that has not entered cold drawing device 3. Demolding plate 1004 supports the portion of preform that has entered cold drawing device 3. In the preform part, the drawing die in the cold drawing device 3 deforms the preform. After drawing, the demolding mechanism 10 separates the preform from the extrusion rod 803. The drawn preform rolls along the demolding plate 1004 onto the transport mechanism 7. After completion, the main oil cylinder 202 returns to its original position with the extrusion rod 803. During this process, the filling valve 22 is used for rapid oil discharge during the return stroke of the main oil cylinder 202. S8: Preform cutting: The preform has irregular excess material or burrs caused by deformation at both ends after cold drawing. It needs to be trimmed through the cutting process. First, the preform after cold drawing is fixed on a special fixture. Then, high-precision cutting equipment is used to cut the two ends of the preform according to the design dimensions. During the cutting process, an infrared positioning device ensures that the cut is perpendicular to the bottle preform axis, with deviations controlled within the allowable range. After cutting, a grinding wheel is used to polish the cut edges, removing burrs and flash to ensure a smooth transition and prevent stress concentration or scratches caused by sharp edges in subsequent processes. Simultaneously, the length of the preform after cutting is inspected to ensure it meets the dimensional requirements of the next process, with tolerances controlled within the specified range. High-strength material-manufactured preforms allow for cold deformation processing, preventing surface cracking defects, reducing wall thickness deviation, achieving uniform wall thickness, and resulting in preform quality superior to similar preforms manufactured using steel billet drawing processes. The reduced size of the preform achieves lightweighting, saving materials and meeting carbon reduction targets. Minor defects on the inner and outer surfaces, such as oxide pits, wire drawing, or ridges, are completely eliminated during cold drawing deformation, resulting in a defect-free surface and improved safety performance of the cylinder. The secondary cold drawing process further densifies the material structure, enhancing the cylinder's material properties and further promoting safe use. A matching cold-drawing mandrel structure was designed to address the complex concave bottom structure of the hot-stamped preform, resulting in a preform bottom structure with good fatigue resistance. Digital control technology ensures stable preform quality, high yield, and high production efficiency after cold drawing.

[0019] This application also provides a device for cold drawing composite forming of large-diameter bottle preforms from steel billets. Based on the aforementioned process for cold drawing composite forming of large-diameter bottle preforms from steel billets, referring to Figures 1, 4, 5, and 6, it includes a base 1, a pushing mechanism 2, a cold drawing device 3, a feeding mechanism 4, a transport mechanism 7, a disassembly mechanism 8, a support mechanism 9, a demolding mechanism 10, and four support columns 24. The feeding mechanism 4 includes a horizontal plate 401 fixedly connected to the top of the four support columns 24. Two limiting plates 402 are fixedly connected to the top of the horizontal plate 401. A support frame 403 is fixedly connected to the side, a hydraulic cylinder 404 is fixedly installed on the top of the support frame 403, a hydraulic rod 405 is fixedly installed inside the hydraulic cylinder 404, a T-shaped block 406 is fixedly connected to the bottom end of the hydraulic rod 405, a first electric push rod 407 is fixedly installed on the side of the T-shaped block 406, a push plate 408 is fixedly connected to one end of the first electric push rod 407, a feeding plate 409 is fixedly connected to the side of the push plate 408, several preform bodies 410 are placed on the top of the horizontal plate 401, and an infrared sensor 411 is provided on the top of the support frame 403.A fixed box 412 is fixedly connected to the bottom of the horizontal plate 401. A first drive motor 417 is fixedly mounted on the side of the fixed box 412 via a mounting plate. First bearings 418 are fixedly connected to both sides of the inner wall of the fixed box 412. A first rotating shaft 419 is rotatably connected inside each of the two first bearings 418. One end of one of the first rotating shafts 419 is fixedly connected to the output shaft of the first drive motor 417. A threaded rod 420 is fixedly connected to one end of both first rotating shafts 419. A movable frame 41 is threadedly connected to the surface of the threaded rod 420. 3. A second electric push rod 414 is fixedly installed on the top of the movable frame 413. A semi-circular support plate 415 is fixedly connected to the top of the second electric push rod 414. Two semi-circular seats 416 are fixedly connected to the side of the horizontal plate 401. A rough pad 23 is provided on the top of the horizontal plate 401. Two sliding rods 25 are fixedly connected to the inner wall side of the fixed box 412. The movable frame 413 is slidably connected to the surface of the sliding rods 25. By setting the feeding mechanism 4, after the infrared sensor 411 detects the preform body 410 on the horizontal plate 401, the first drive... The motor 417 starts, driving the threaded rod 420 to rotate via the first rotating shaft 419, causing the moving frame 413 to slide along the slide rod 25 between the two semi-circular seats 416. Then, the second electric push rod 414 extends and pushes the semi-circular support plate 415 parallel to the semi-circular seat 416. Subsequently, the hydraulic cylinder 404 drives the hydraulic rod 405 to descend, thereby causing the T-shaped block 406 to move the push plate 408 to the preform body 410 at the beginning of the feeding process, while the feeding plate 409 is located at the preform body 410 at the end of the feeding process. After that, the first electric push rod 407 extends. The pusher plate 408 pushes the preform body 410, which is initially fed, into the two semi-circular seats 416, while the feeding plate 409 pushes the preform body 410, which is continuously fed forward, to the front. Finally, the preform body 410 is transported to the extrusion rod 803 by the moving frame 413 and the semi-circular support plate 415. This achieves the purpose of replacing manual feeding, realizing the effect of automated operation through infrared sensing and mechanical linkage, while avoiding the safety hazards caused by manual contact. By setting a rough pad 23, the friction is increased to prevent the preform body 410 from sliding.

[0020] Please refer to Figures 1, 2, 3, and 4. The pushing mechanism 2 includes a fixed plate 201 fixedly connected to the top of the base 1. A main hydraulic cylinder 202 is fixedly installed on the side of the fixed plate 201. A piston rod 203 is fixedly installed inside the main hydraulic cylinder 202. A support seat 13 is fixedly connected to the surface of the main hydraulic cylinder 202. Three prestressed support columns 18 are fixedly connected to the interior of the fixed plate 201 and the interior of the cold drawing device 3. By setting the pushing mechanism 2, the main hydraulic cylinder 202 can drive the piston rod 203 to extend and retract forward, thus providing extrusion power for subsequent applications. By setting the support seat 13, the following is achieved: To enhance the stability of the main hydraulic cylinder 202, prestressed support columns 18 are installed to counteract the reverse force generated during cold drawing, ensuring the relative position stability of the fixed plate 201 and the cold drawing device 3. The cold drawing device 3 is fixedly installed on the top of the base 1, and a support platform 5 is fixedly connected to the top of the fixed plate 201. A power station 6 is fixedly installed on the top of the support platform 5. A filling valve 22 is installed on the top of the main hydraulic cylinder 202, and an oil supply pipe 21 is fixedly connected inside the filling valve 22. The other end of the oil supply pipe 21 is fixedly connected to the inside of the power station 6. A railing 11 is fixedly connected to the top of the support platform 5. Four support legs 12 are fixedly connected to the bottom of the support platform 5, a support frame 14 is fixedly connected to the side of the base 1, and four fastening seats 15 are fixedly connected to the top of the support frame 14. Two handles 16 are fixedly connected to the side of the fence 11, a staircase 17 is fixedly connected to the side of the support platform 5, and four support columns 24 are fixedly connected to the top of the base 1. By setting up the cold drawing device 3, the purpose of cold drawing the preform body 410 is achieved. By setting up the support platform 5, the purpose of providing installation space for the power station 6 is achieved. By setting up the power station 6, the filling valve 22, and the oil delivery pipe 21, the power station 6 can be powered. Power station 6 supplies oil to main cylinder 202 through oil supply pipe 21, and filling valve 22 facilitates control of oil supply flow, thus achieving the purpose of providing power to extrusion rod 803. By setting up fence 11, the purpose of protecting maintenance personnel is achieved. By setting up support legs 12, the purpose of providing rigid support to power station 6 is achieved. By setting up support frame 14 and fastening seat 15, the purpose of providing stable support to transport mechanism 7 is achieved. By setting up handle 16 and stairs 17, the purpose of facilitating climbing by maintenance personnel is achieved. By setting up support column 24, the purpose of providing rigid support to feeding mechanism 4 is achieved.

[0021] Referring to Figures 3 and 7, the transport mechanism 7 includes two elongated plates 701 fixedly connected to the top of four fastening seats 15. A second drive motor 702 is fixedly mounted on the side of one of the elongated plates 701. Four second bearings 703 are fixedly connected to the sides of the two elongated plates 701. A second rotating shaft 704 is rotatably connected inside each of the two sets of second bearings 703. One end of one of the second rotating shafts 704 is fixedly connected to the output shaft of the second drive motor 702. Pulleys 707 are fixedly connected to the surfaces of both second rotating shafts 704. A rubber belt 705 is driven between the two pulleys 707, and a conveyor belt 706 is driven between the two second rotating shafts 704. By setting up the transport mechanism 7, the cold-drawn preform body 410 can be rolled from the demolding template 1004 onto the conveyor belt 706. Subsequently, the second drive motor 702 drives the pulleys 707 to rotate via the second rotating shaft 704, which in turn drives the conveyor belt 706 to rotate, transporting the preform body 410 to the next process. The rubber belt 705 in this structure prevents the surface of the preform body 410 from being exposed to the wind. Scratches are prevented. The conveyor belt 706 operates at a speed synchronized with the cold drawing rhythm, achieving continuous production and reducing bump damage caused by the accumulation of preform bodies 410. The disassembly mechanism 8 includes a connecting seat 801 fixedly connected to one end of the piston rod 203. A screw 802 is threaded inside the connecting seat 801, and a pressing rod 803 is threaded on the surface of the screw 802. A guide rail 19 is fixedly connected to the side of the fixing plate 201 and the side of the cold drawing device 3. A slider 20 is slidably connected inside the guide rail 19, and the side of the slider 20 is fixedly connected to the connecting... On the surface of the seat 801, a disassembly mechanism 8 is provided. When the extrusion rod 803 needs to be replaced, the old extrusion rod 803 can be removed by unscrewing the screw 802 on the connecting seat 801. After replacing the extrusion rod 803, the screw 802 is tightened again to fix it. The slider 20 will slide along the guide rail 19, which ensures the coaxiality of the extrusion rod 803 and the piston rod 203. The screw 802 connection method of this structure improves the tightness of the extrusion rod 803, while the guide rail 19 and the slider 20 cooperate to ensure the stable movement of the extrusion rod 803 and improve the versatility of the equipment.

[0022] Please refer to Figures 3, 7, and 8. By setting the support mechanism 9, the third electric push rod 902 can push the lifting plate 903 to the surface of the extrusion rod 803, thus achieving the purpose of auxiliary support for the extrusion rod 803. The demolding mechanism 10 includes a horizontal block 1001 and a demolding template 1004 fixedly connected to the side of the cold drawing device 3. A fourth electric push rod 1002 is fixedly installed on the top of the horizontal block 1001, and a clamping plate 1003 is fixedly connected to the bottom end of the fourth electric push rod 1002. The clamping plate 1003 and the demolding template 1004 are connected to each other. Rubber pads 1005 are provided on the surface of 4. By setting the demolding mechanism 10, after cold drawing, the fourth electric push rod 1002 extends and pushes the clamping plate 1003 down to cooperate with the demolding plate 1004 to clamp the preform body 410. Then, the extrusion rod 803 returns under the drive of the main oil cylinder 202. The preform body 410 separates from the extrusion rod 803 under the action of clamping force, realizing the purpose of easy release of the preform body 410. By setting the rubber pads 1005, damage to the surface of the preform body 410 is avoided during clamping.

[0023] The implementation principle of this application embodiment is as follows: First, the preform body 410 to be cold-drawn is placed on the horizontal plate 401. Subsequently, the limiting plate 402 limits the preform body 410 to prevent it from sliding off both sides of the horizontal plate 401. The rough pad 23 increases the friction between the preform body 410 and the horizontal plate 401 to prevent the preform body 410 from sliding on its own. Then, the feeding mechanism 4 starts working. After the infrared sensor 411 detects the preform body 410 on the horizontal plate 401, the first drive motor 417 starts and drives the threaded rod 420 to rotate through the first rotating shaft 419, so that the moving frame 413 slides along the slide rod 25 between the two semi-arc seats 416. Then, the second electric push rod 414 extends and pushes the semi-arc support. Plate 415 rises to a height parallel to the semi-circular seat 416, facilitating the lifting of the preform body 410 from the horizontal plate 401. Then, hydraulic cylinder 404 drives hydraulic rod 405 to descend, simultaneously lowering T-block 406, first electric push rod 407, push plate 408, and feeding plate 409. This aligns push plate 408 with the starting preform body 410 requiring feeding, and feeding plate 409 with the ending preform body 410 requiring further feeding. Then, first electric push rod 407 extends, push plate 408 pushes the starting preform body 410 into the two semi-circular seats 416, and simultaneously feeding plate 409 pushes the ending preform body 410 forward, achieving the replacement of subsequent cylinders. Subsequently, the moving frame 413 moves along threaded rod 4... Driven by the 20, the preform body 410 on the semi-circular support plate 415 is transported to the front of the extrusion rod 803. At this time, the support mechanism 9 starts to work, and the third electric push rod 902 extends to push the lifting plate 903 to rise, supporting the middle of the extrusion rod 803 and enhancing the stability of the extrusion rod 803. After that, the pushing mechanism 2 starts, and the power station 6 supplies oil to the main oil cylinder 202 through the oil supply pipe 21. The main oil cylinder 202 drives the piston rod 203 to move forward along the guide rail 19. The piston rod 203 drives the extrusion rod 803 to move forward, so that the preform body 410 is fitted onto the extrusion rod 803. After the feeding mechanism 4 is reset, the extrusion rod 803 continues to move forward with the preform body 410, and performs cold drawing operation through the cold drawing device 3. During this process... Three prestressed supports 18 counteract the reverse force generated by cold drawing, ensuring equipment stability. Finally, after cold drawing, the demolding mechanism 10 operates, the fourth electric push rod 1002 extends and pushes the clamping plate 1003 down, cooperating with the demolding plate 1004 to clamp the preform body 410. The extrusion rod 803 returns under the drive of the main oil cylinder 202, and the preform body 410 separates from the extrusion rod 803 under the action of clamping force, and rolls down along the demolding plate 1004 onto the conveyor belt 706 of the transport mechanism 7. Then the second drive motor 702 starts, and drives the conveyor belt 706 to rotate through the second rotating shaft 704, pulley 707 and rubber belt 705, transporting the preform body 410 to the next process, completing the entire cold drawing process.After a period of use, if it is necessary to replace the extrusion rod 803 with a different specification, the screw 802 on the connecting seat 801 can be unscrewed, the old extrusion rod 803 can be removed and replaced with a new one. Alternatively, if the power station 6 malfunctions, maintenance personnel can use the stairs 17 and handles 16 to climb onto the support platform 5 for maintenance.

Claims

1. A process for the combined forming of large-diameter bottle preforms by punching and drawing steel billets, characterized in that... The process includes the following steps: S1: Billet preparation: Using standard-sized billets, the billets are sawn according to the set cutting weight. The diagonals are designed according to process requirements, the radius (R) is designed according to standard dimensions, and the inner dimensions of the lower die are designed according to fitting requirements. At a specific heating temperature, the diagonals of the billet will experience corresponding thermal expansion due to the coefficient of thermal expansion of steel. That is, when the billet is vertically pressed at this heating temperature, the diagonal dimension changes to a specific value due to thermal expansion. When matched with the lower die dimensions, this ensures that the billet can smoothly enter the lower die and that the gap between the billet and the lower die is controlled within the allowable range. S2: Billet heating: The billet is heated to the process-set temperature and held at that temperature for a specified time to ensure that the temperature inside and outside the billet is consistent. This ensures that the metal flow during stamping and hot drawing is not uneven due to temperature deviation. S3: Hole filling: During stamping and drawing, a floating beam is used for lower-end positioning and clamping alignment technology to ensure that the entire reverse extrusion process is consistent during vertical pressing. Finally, the punch and the lower die are positioned at the center of axisymmetry, ensuring the uniformity of the stamped bottle preform's skin thickness from the perspective of die reliability. The vertically pressed punched preform undergoes multiple rounds of ring die extrusion within a specific temperature range, followed by multiple rounds of cross-staggered covering rolling die rolling, ultimately forming a drawn bottle preform with inner and outer diameters meeting design tolerance requirements. During the overall ring die rolling, the punched preform undergoes multiple consecutive drawing passes, resulting in a reduction in overall outer diameter and wall thickness, and a corresponding reduction in wall thickness deviation. In the cross-staggered rolling die design, each pass is staggered at a set angle, which, while finishing the outer surface, also plays a role in uniformizing the wall thickness. S4: Bottle preform annealing: The bottle preform is annealed at the process-set temperature to eliminate uneven hardness after hot drawing and to control the overall hardness of the bottle preform within a suitable range for subsequent processing, facilitating metal deformation during subsequent cold drawing. S5: Bottle preform internal and external polishing: The oxide scale of the annealed bottle preform is polished clean, creating favorable conditions for subsequent phosphating, saponification, and drawing processes. S6: Preform phosphating and saponification: The annealed preform is subjected to phosphating and saponification to form a saponified layer on its surface, ensuring lubrication of the metal flow during the drawing process; S7: Preform cold drawing: During cold drawing, the power station (6) supplies oil to the main cylinder (202), causing the main cylinder (202) to advance along the guide rail (19). The piston rod (203) inside the main cylinder (202) pushes the extrusion rod (803). The extrusion rod (803) advances to the rear of the conveying mechanism under the support of the support mechanism (9) and stops. The feeding mechanism (4) transports the preform to the front of the extrusion rod (803). The extrusion rod (803) moves forward so that the preform fits onto the extrusion rod (803). The feeding mechanism (4) is removed, and the extrusion rod (803) continues to move forward with the preform through the cold drawing device (3). The horizontal plate (401) and the rough pad (23) support the part of the preform that has not entered the cold drawing device (3). The demolding plate (1004) supports the part of the preform that has entered the cold drawing device (3). The drawing die in the cold drawing device (3) deforms the preform. After the drawing is completed, the preform is demolded. The die mechanism (10) separates the preform from the extrusion rod (803). After being drawn, the preform rolls along the stripping die (1004) onto the transport mechanism (7). After completion, the main cylinder (202) returns to its original position with the extrusion rod (803). During this process, the filling valve (22) is used to quickly discharge oil during the return stroke of the main cylinder (202). S8: Preform cutting: The preforms after cold drawing have irregular excess material or burrs caused by deformation at both ends. They need to be trimmed through the cutting process. First, the preforms after cold drawing are fixed on a special fixture. High-precision cutting equipment is used to cut both ends of the preform according to the design dimensions. During the cutting process, an infrared positioning device is used to ensure that the cut is perpendicular to the preform axis and the deviation is controlled within the allowable range. After the cut is completed, a grinding wheel is used to grind the cut edge to remove burrs and flash, so that the edge transitions smoothly and avoids stress concentration or scratches caused by sharp edges in subsequent processes. At the same time, the length of the preform after cutting is checked to ensure that it meets the dimensional requirements of the next process and the tolerance is controlled within the specified range.

2. A device for cold drawing and composite forming of large-diameter bottle preforms from steel billets, based on the process for cold drawing and composite forming of large-diameter bottle preforms from steel billets according to claim 1, characterized in that: The system includes a base (1), a pushing mechanism (2), a cold drawing device (3), a feeding mechanism (4), a transport mechanism (7), a disassembly mechanism (8), a support mechanism (9), a demolding mechanism (10), and four support columns (24). The feeding mechanism (4) includes a horizontal plate (401) fixedly connected to the top of the four support columns (24). Two limiting plates (402) are fixedly connected to the top of the horizontal plate (401). Support frames (403) are fixedly connected to the sides of the two limiting plates (402). A hydraulic cylinder is fixedly installed on the top of the support frame (403). (404), a hydraulic rod (405) is fixedly installed inside the hydraulic cylinder (404), a T-shaped block (406) is fixedly connected to the bottom end of the hydraulic rod (405), a first electric push rod (407) is fixedly installed on the side of the T-shaped block (406), a push plate (408) is fixedly connected to one end of the first electric push rod (407), a feeding plate (409) is fixedly connected to the side of the push plate (408), a number of preform bodies (410) are placed on the top of the horizontal plate (401), and an infrared sensor (410) is provided on the top of the support frame (403). 11); A fixed box (412) is fixedly connected to the bottom of the horizontal plate (401), and a first drive motor (417) is fixedly installed on the side of the fixed box (412) by a mounting plate. A first bearing (418) is fixedly connected to both sides of the inner wall of the fixed box (412). A first rotating shaft (419) is rotatably connected inside the two first bearings (418). One end of one of the first rotating shafts (419) is fixedly connected to the output shaft of the first drive motor (417), and a threaded rod (420) is fixedly connected to one end of both first rotating shafts (419). The threaded rod (420) is threadedly connected to a movable frame (413). A second electric push rod (414) is fixedly installed on the top of the movable frame (413). A semi-circular support plate (415) is fixedly connected to the top of the second electric push rod (414). Two semi-circular seats (416) are fixedly connected to the side of the horizontal plate (401). A rough pad (23) is provided on the top of the horizontal plate (401). Two sliding rods (25) are fixedly connected to the inner wall side of the fixed box (412). The movable frame (413) is slidably connected to the surface of the sliding rods (25).

3. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 2, characterized in that: The pushing mechanism (2) includes a fixed plate (201) fixedly connected to the top of the base (1), a main oil cylinder (202) fixedly installed on the side of the fixed plate (201), a piston rod (203) fixedly installed inside the main oil cylinder (202), a support seat (13) fixedly connected to the surface of the main oil cylinder (202), and three prestressed support columns (18) fixedly connected inside the fixed plate (201) and inside the cold drawing device (3).

4. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 3, characterized in that: A cold drawing device (3) is fixedly installed on the top of the base (1). A support platform (5) is fixedly connected to the top of the fixed plate (201). A power station (6) is fixedly installed on the top of the support platform (5). A filling valve (22) is provided on the top of the main oil cylinder (202). An oil delivery pipe (21) is fixedly connected inside the filling valve (22). The other end of the oil delivery pipe (21) is fixedly connected inside the power station (6). A fence (11) is fixedly connected to the top of the support platform (5). Four support legs (12) are fixedly connected to the bottom of the support platform (5). A support frame (14) is fixedly connected to the side of the base (1). Four fastening seats (15) are fixedly connected to the top of the support frame (14). Therefore, two handles (16) are fixedly connected to the side of the fence (11). A staircase (17) is fixedly connected to the side of the support platform (5). Four support columns (24) are fixedly connected to the top of the base (1).

5. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 4, characterized in that: The transport mechanism (7) includes two elongated plates (701) fixedly connected to the top of four fastening seats (15). A second drive motor (702) is fixedly installed on the side of one of the elongated plates (701). Four second bearings (703) are fixedly connected to the sides of the two elongated plates (701). A second rotating shaft (704) is rotatably connected inside both sets of second bearings (703). One end of one of the second rotating shafts (704) is fixedly connected to the output shaft of the second drive motor (702). Pulleys (707) are fixedly connected to the surfaces of the two second rotating shafts (704). A rubber belt (705) is driven between the two pulleys (707). A conveyor belt (706) is driven between the two second rotating shafts (704).

6. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 3, characterized in that: The disassembly mechanism (8) includes a connecting seat (801) fixedly connected to one end of the piston rod (203). The connecting seat (801) is internally threaded with a screw (802). The screw (802) is threadedly connected to a pressing rod (803). The side of the fixing plate (201) is fixedly connected to the side of the cold drawing device (3) with a guide rail (19). The guide rail (19) is internally slidably connected with a slider (20). The side of the slider (20) is fixedly connected to the surface of the connecting seat (801).

7. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 6, characterized in that: The support mechanism (9) includes a fixed frame (901) fixedly connected to the top of the base (1), a third electric push rod (902) fixedly installed at the bottom of the fixed frame (901), a lifting plate (903) fixedly connected to the top of the third electric push rod (902), and a pressing rod (803) overlapping the top of the lifting plate (903).

8. The apparatus for composite forming of large-diameter bottle preforms by punching and drawing steel billets according to claim 4, characterized in that: The demolding mechanism (10) includes a horizontal block (1001) and a demolding template (1004) fixedly connected to the side of the cold drawing device (3). A fourth electric push rod (1002) is fixedly installed on the top of the horizontal block (1001). A clamping plate (1003) is fixedly connected to the bottom of the fourth electric push rod (1002). Rubber pads (1005) are provided on the surfaces of the clamping plate (1003) and the demolding template (1004).

Images