An envelope-rolling forming apparatus and process for a tubular member with internal ribs

Abstract

The application discloses an envelope-rolling forming device and process of a cylinder with inner ribs, and the forming device comprises a workbench, a clamping seat, a swing pressure roller, a side pressure roller and a core roller; the swing pressure roller continuously rolls the top surface of a ring blank through a compound motion of vertical motion and circumferential swing; the side pressure roller continuously rolls the outer lateral surface of the ring blank through a compound motion of rotation, revolution and radial motion; the core roller and the side pressure roller form a stable radial constraint forming system for the lateral wall of the ring blank; and the internal metal material of the ring blank directionally and plastically flows into the core roller die cavity under the synergistic action of the axial swing rolling force and the radial constraint force. The envelope-rolling compound process method is adopted, the production process flow is simplified, the manufacturing cost is significantly reduced, and the compound axial radial loading formed by the swing pressure roller and the side pressure roller can form the structure with inner ring ribs in a short process and high precision, realizes near-net forming with less cutting, and greatly improves the material utilization rate.

Description

Technical Field

[0001] This invention belongs to the field of metal plastic forming technology, specifically an envelope-roll forming device and process for cylindrical parts with internal ribs. Background Technology

[0002] like Figure 1 As shown, titanium alloy cylindrical sections are generally made of lightweight, high-strength titanium alloys such as TC4, TC4ELI (low-gap TC4 alloy), Ti80, and Ti62A. Each section has numerous annular thin-walled internal ribs, and the overall structure is further strengthened by thicker external ribs (or flanges) at the joints. This is a typical complex structure made of difficult-to-deform materials, posing a significant challenge to its high-performance, high-precision forming and manufacturing. For large-size titanium alloy cylindrical sections, a modular manufacturing approach is generally adopted.

[0003] Near-net-shape forming technology can directly produce components with shapes, dimensions, and microstructures close to the finished product through plastic forming, significantly reducing subsequent machining allowances, greatly improving material utilization, and ensuring continuous and complete metal flow lines. It effectively refines grains, improves part density and comprehensive mechanical properties, and in particular, improves the strength, plasticity, and fatigue life of components. This technology can also simplify the process flow, improve dimensional accuracy and production stability, and reduce production energy consumption and manufacturing costs. For integral components with complex structures such as internal ribs, it can achieve near-net-shape forming, avoiding the cutting of metal flow lines by machining, and fundamentally improving the structural integrity and service reliability of components.

[0004] The existing manufacturing method for titanium alloy cylindrical parts with inner and outer ring ribs is unit die forging and milling, specifically: ① First, a titanium alloy casting billet is used for primary machining (more than 10 heats for opening and re-forging), then a ring billet is prepared by heating and upsetting and punching, and then the ring part is expanded by heating and radial rolling; ② The inner ring rib structure is machined into the expanded ring part by CNC machining center.

[0005] Existing processes suffer from problems such as long processing time, high cost, difficulty in forming the ring rib structure of cylindrical shells by axial and radial rolling, resulting in low material utilization (extensive machining), and the axial and radial rolling process of thin-walled large-size rings is prone to various forming defects such as cracking and out-of-roundness; the advantages of near-net-shape forming are not fully utilized. Summary of the Invention

[0006] To solve the above-mentioned technical problems, this invention proposes an envelope-roll forming device and process for cylindrical parts with internal ribs. The envelope-rolling composite process method simplifies the production process and significantly reduces the manufacturing cost. Furthermore, by using the radial loading of the composite shaft formed by the cooperation of the swing pressure roller and the side pressure roller, the structure with internal ring ribs can be formed with high precision in a short process, achieving near-net-shape forming with less cutting and greatly improving the material utilization rate.

[0007] The envelope-roll forming process proposed in this invention can achieve near-net-shape forming of cylindrical parts with internal ribs: A oscillating pressure roller rotates around the main shaft of the equipment at a preset angle (typically 1°~5°), continuously applying periodic local pressure to the upper surface of the ring blank. Under the synergistic effect of axial upsetting by the oscillating pressure roller and radial constraint by the side pressure rollers, the plastic flow metal inside the ring blank is forced into the preset mold cavity of the core roller. Through continuous pressure transmission and metal filling, the mold cavity is gradually filled, directly forming an inner ring rib structure integrated with the cylindrical substrate. Finally, when the axial compression of the ring blank and the filling degree of the inner rib reach the preset values, forming stops, resulting in a cylindrical blank with internal ribs that has continuous metal flow lines, integrated inner ribs with the cylindrical wall, and dimensional accuracy close to that of the finished product. This process can significantly reduce subsequent machining allowances and solves the problems of high cost, long forming cycle, and low material utilization of traditional processes, thereby achieving low-cost, short-process, and near-net-shape forming of complex titanium alloy cylindrical parts with internal ribs.

[0008] One technical solution adopted in this invention is: An enveloping-roll forming device for a cylindrical part with internal ribs includes a worktable, a clamping seat fixed on the top surface of the worktable, and an axial feeding mechanism located above the clamping seat. The ring blank to be formed is clamped on the top of the clamping seat. The bottom end of the axial feeding mechanism is rotatably connected to a swing roller through a bending shaft. The axial feeding mechanism is provided with a swing rotation drive mechanism that drives the bending shaft to rotate. A side pressure roller is provided on the outer side of the side wall of the ring blank, and a core roller is provided on the inner side of the side wall. The central axis of the side pressure roller, the core roller and the ring blank are located in the same vertical plane. An annular core roller cavity is opened in the outer wall of the core roller. The worktable is equipped with a side pressure rotation drive mechanism that drives the side pressure roller to revolve around the ring blank and a synchronous rotation drive mechanism that drives the core roller to revolve synchronously. The top of the side pressure rotation drive mechanism is provided with a first linear drive mechanism for driving the side pressure roller to feed radially. The first linear drive mechanism is provided with a side pressure rotation drive mechanism for driving the side pressure roller to rotate. The top of the synchronous rotation drive mechanism is provided with a second linear drive mechanism for driving the core roller to feed radially. The oscillating roller continuously rolls the top surface of the ring blank through a combination of vertical and circumferential oscillation. The side rollers continuously roll the outer surface of the ring blank through a combination of rotation, revolution, and radial motion. The core roller and the side rollers form a stable radial constraint forming system for the sidewall of the ring blank. Under the synergistic effect of axial rolling force and radial constraint force, the metal material inside the ring blank flows in a directional plastic manner into the core roller mold cavity.

[0009] Furthermore, the side-pressure rotation drive mechanism includes an outer turntable rotatably mounted on the top surface of the worktable and a first drive motor fixedly mounted on the bottom of the worktable. The output shaft end of the first drive motor is fixedly connected to a first driving gear, and the bottom of the outer turntable is coaxially connected to a first driven gear that meshes with the first driving gear.

[0010] Furthermore, the first linear drive mechanism includes a first servo hydraulic cylinder fixedly mounted on the top surface of the outer turntable, a first bracket connected to the output shaft end of the first servo hydraulic cylinder and slidably mounted on the top surface of the outer turntable, and a side pressure roller rotatably mounted inside the first bracket.

[0011] Furthermore, the side pressure rotation drive mechanism includes a second drive motor fixedly mounted on the top of the first bracket, a second drive gear fixedly connected to the output shaft end of the second drive motor, and a second driven gear meshing with the second drive gear fixedly connected to the top of the rotating shaft of the side pressure roller.

[0012] Furthermore, the synchronous rotation drive mechanism includes an inner turntable rotatably mounted on the top surface of the worktable and a third drive motor fixedly installed at the bottom of the worktable. The output shaft end of the third drive motor is fixedly connected to a second driving gear, and the bottom of the inner turntable is coaxially connected to a second driven gear that meshes with the second driving gear.

[0013] Furthermore, the bottom end face of the side pressure roller and the outer top end face of the clamping seat are located in the same horizontal plane, and the bottom end face of the core roller and the inner top end face of the clamping seat are located in the same horizontal plane.

[0014] Furthermore, when the bottom end face of the swing roller is in its lowest position, the outer part of the bottom end face rolls in contact with the top end face of the side roller, and the inner part of the bottom end face rolls in contact with the top end face of the core roller.

[0015] An enveloping roll forming process for cylindrical parts with internal ribs is also provided, using the enveloping roll forming apparatus for cylindrical parts with internal ribs as described above, including the following steps: S1. The ring blank is prepared by hot isostatic pressing. S2. Place the heated ring blank in the clamping seat, and feed the side pressure roller and core roller radially, gradually approaching the side wall surface of the ring blank until contact. S3. The swing roller descends to the bottom of its swing grinding chamber end face and contacts the upper end face of the ring billet, and establishes stable axial loading conditions. S4. The swing roller continuously swings at a preset swing angle and feeds axially at a preset feed speed to continuously roll and load the ring blank. The ring blank material undergoes uniform plastic deformation in the axial direction and gradually flows stably. S5. The side pressure roller rotates with preset parameters and revolves around the ring blank, and superimposed with radial feed motion to apply a continuous and stable radial clamping force to the outer surface of the ring blank. The core roller, the side pressure roller and the central axis of the ring blank always remain coplanar. S6. Under the combined action of axial rolling force and radial constraint force, the metal material inside the ring billet undergoes directional plastic flow, and the inner metal is gradually forced into the core roller mold cavity until the metal gradually fills the mold cavity and forms a stable structure. S7. The swing roller stops swinging and moves upward to reset; the side roller stops rotating and moves outward to reset; the core roller moves inward to reset. S8. Remove the formed workpiece from the clamping seat.

[0016] Furthermore, the oscillating speed of the oscillating roller is 15~40 rpm, and the axial feed speed is 3~5 mm / min.

[0017] Furthermore, the rotational speed of the side pressure roller is 20~60 rpm, the revolution speed is 0.5~3 rpm, and the radial feed speed is 1~2 mm / min.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention adopts a combined forming process of oscillating rolling and roller pressing, which simplifies the overall process. Through the synergistic effect of the oscillating roller, side roller, and core roller, continuous and progressive plastic deformation of the ring component is achieved. It can obtain formed parts with high dimensional accuracy and uniform cross-section in a shorter process path, breaking through the limitations of traditional integral molding on equipment tonnage and structural complexity, achieving near-net-shape forming, and significantly improving material utilization. 2. In the forming process of the present invention, the side pressure roller and the core roller form a stable clamping and constraint system for the ring blank. While ensuring the continuous rotation of the ring, the inner and outer diameter dimensions can be effectively controlled, which improves the stability and dimensional consistency of the forming process and helps to improve roundness and coaxiality. The forming surface at the lower end of the swing pressure roller maintains a stable contact relationship with the surface of the ring blank and establishes a matching motion with the roller system. Under high-speed swing rolling conditions, the influence of off-center load and vibration is effectively suppressed, ensuring the stability of the forming trajectory and the coaxiality and roundness accuracy of the ring. 3. The oscillating roller of the present invention adopts a local high-speed oscillating loading method, which allows the material to gradually accumulate plastic deformation in a smaller deformation zone, reducing the overall forming force and improving the material flowability. Under the action of continuous loading and rotational inertia, it is beneficial to achieve uniform wall thickness distribution and dense structure. The local high-speed oscillating loading method, together with the circumferential continuous motion provided by the side roller and the stable constraint of the inner diameter by the core roller, forms a synergistic deformation mode of "radial loading + circumferential feeding". Through the progressive continuous deformation path design, the material is guided to flow uniformly along the circumference, so that the material can achieve continuous and controllable plastic flow during the forming process, and the deformation can be gradually accumulated in space and time, taking into account both forming accuracy and deformation efficiency. Through continuous hot plastic deformation, the grains can be effectively refined, the metal flow distribution can be improved, the stress concentration can be effectively reduced, and the generation of defects such as cracks and folds can be reduced. At the same time, the density and uniformity of the structure are improved, and the strength, toughness and fatigue life of the component are improved. 4. By constructing an integrated system of a swing head mechanism and a roller drive device, combined with a stable support and control unit, the present invention can realize continuous and automated operation of the forming process. The equipment structure is relatively simple, the process adaptability is strong, and it is suitable for the flexible manufacturing needs of ring parts of different sizes and cross-sectional shapes. 5. The present invention adopts hot isostatic pressing of the blank and then takes it out at a medium-high temperature (without cooling to room temperature) and directly enters the subsequent heating and forming process. This effectively realizes the thermal connection of the process, reduces the number of thermal cycles, improves the material structure stability and forming performance, and significantly reduces energy consumption and improves production efficiency. Attached Figure Description

[0019] Figure 1 A schematic diagram of the structure of the formed part processed by the forming apparatus and process of the present invention; Figure 2 This is a three-dimensional structural schematic diagram of the envelope-roll forming apparatus for cylindrical parts with internal ribs according to the present invention. Figure 3 This is a cross-sectional structural schematic diagram of the envelope-roll forming apparatus for cylindrical parts with internal ribs according to the present invention. Figure 4 One of the structural schematic diagrams showing the side pressure roller and core roller assembled on the worktable; Figure 5 The second schematic diagram shows the side pressure roller and core roller assembled on the worktable. Figure 6 This is a schematic diagram of the side-pressure rotation drive mechanism and the synchronous rotation drive mechanism assembled on the worktable (with the outer turntable and inner turntable removed); Figure 7 This is a structural schematic diagram showing the forming working state of the swing roller, side roller, and core roller.

[0020] In the diagram: 1. Clamping seat; 2. Axial feed mechanism; 201. Third servo hydraulic cylinder; 202. Connector; 203. Stud; 204. Lifting plate; 205. Guide column; 3. Bending shaft; 4. Swinging pressure rotation drive mechanism; 5. Side pressure rotation drive mechanism; 501. Outer turntable; 502. First drive motor; 503. First driving gear; 504. First driven gear; 505. First thrust bearing; 506. Second thrust bearing; 6. Synchronous rotation drive mechanism; 601. Inner turntable; 602. Third drive motor; 603. Second driving gear 604. Wheel; 605. Second driven gear; 606. Third thrust bearing; 7. First linear drive mechanism; 701. First servo hydraulic cylinder; 702. First bracket; 703. First slide rail slider assembly; 704. First mounting base; 8. Side pressure rotation drive mechanism; 801. Second drive motor; 802. Second driving gear; 803. Second driven gear; 9. Second linear drive mechanism; 10. Swinging pressure roller; 20. Side pressure roller; 30. Core roller; 100. Ring blank; 110. Worktable; 120. Support column; 130. Column; 140. Beam plate. Detailed Implementation

[0021] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0022] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] See Figure 2 and Figure 3An enveloping-roll forming apparatus for a cylindrical part with internal ribs includes a worktable 110, a clamping seat 1 fixed to the top surface of the worktable 110, and an axial feed mechanism 2 located above the clamping seat 1. The ring blank 100 to be formed is clamped on the top of the clamping seat 1. The worktable 110 has a disc structure, and its bottom surface is fixedly connected to the working area of ​​the forming workshop by several evenly distributed support columns 120. Multiple columns 130 are arranged on the outer side of the worktable 110, and beam plates 140 are fixedly connected to the top of the columns 130 to form a gantry structure for mounting the axial feed mechanism 2. The clamping seat 1 has an annular structure, and an annular groove is formed on its top end face. The radial dimension of the annular groove matches the inner and outer diameter dimensions of the ring blank 100, allowing the bottom end of the ring blank 100 to be vertically embedded in the annular groove for clamping and positioning.

[0025] In this embodiment, the axial feed mechanism 2 employs a servo-controlled hydraulic cylinder device for the vertical feed of the swing roller 3 and the stable output of the swing force. Specifically, the axial feed mechanism 2 includes a third servo hydraulic cylinder 201, a connector 202 fixedly connected to the bottom end of the output rod of the third servo hydraulic cylinder 201, and a lifting plate 204 fixedly connected to the bottom end of the connector 202 via studs 203. Guide columns 205 are symmetrically fixedly connected to both sides of the top surface of the lifting plate 204, and the top of each guide column 205 is movably inserted into the beam plate 140 via a linear bearing. The third servo hydraulic cylinder 201 drives the lifting plate 204 to move vertically and position itself, while the guide columns 205 provide guidance.

[0026] The bottom end of the axial feed mechanism 2 is rotatably connected to the swing roller 10 via the bending shaft 3. The axial feed mechanism 2 contains a swing roller rotation drive mechanism 4 that drives the bending shaft 3 to rotate. The bending shaft 3 is a continuously bent three-section shaft. Its top section is a vertical cylinder, the top of which is rotatably connected to the lifting plate 204 via a bearing and bearing cover, allowing the vertical cylinder to rotate around its vertical axis within the lifting plate 204. The middle section of the bending shaft 3 is an outwardly inclined cylinder bent downwards from the bottom end of the vertical cylinder, and the bottom section of the bending shaft 3 is an inwardly inclined cylinder bent downwards from the bottom end of the outwardly inclined cylinder. The angle between the axis of the inwardly inclined cylinder in the bottom section and the axis of the vertical cylinder in the top section is a preset inclination angle of the swing roller 10, set to 1°~5°. The swing roller 10 is rotatably sleeved on the outside of the bottom section of the bending shaft 3 via a bearing. Thus, when the bending shaft 3 rotates around the vertical axis, the axis of its bottom section rotates within the conical surface, thereby driving the axis of the swing roller 10 to rotate synchronously. The end face of the swing rolling cavity on the bottom surface of the swing roller 10 continuously rolls and contacts the top end of the ring blank 100. The cross-sectional shape of the swing rolling cavity is a rectangle with an open bottom (arranged above and below the groove on the clamping seat 1), which can be fastened to the top of the ring blank 100 and simultaneously contacts the top end face and the inner and outer sides of the top of the ring blank 100, thereby enabling shape control of the top part of the ring blank 100. During the process of the axial feed mechanism 2 driving the lifting plate 204 to move vertically downward, pressure is transmitted to the swing roller 10 through the bending shaft 3, thereby causing the swing roller 10 to continuously roll and press the top surface of the ring blank 100 through a combination of vertical movement and circumferential oscillation during the swing rolling process, so that the top of the ring blank 100 is subjected to uniform and continuous downward pressure and undergoes directional plastic deformation.

[0027] In this embodiment, the swing pressure rotation drive mechanism 4 adopts a servo motor, which is fixedly connected to the center of the top surface of the lifting plate 204 by bolts. Its output shaft is keyed to the top end of the bending shaft 3, so as to accurately control the rotation speed of the bending shaft 3, that is, to realize the control of the swing pressure roller 10 swing cycle.

[0028] A side pressure roller 20 is provided on the outer side of the sidewall of the ring blank 100, and a core roller 30 is provided on the inner side of the sidewall. The central axes of the side pressure roller 20, the core roller 30, and the ring blank 100 are located in the same vertical plane. An annular core roller cavity is formed in the outer wall of the core roller 30. The side pressure roller 20 continuously rolls the outer surface of the ring blank 100 through a combination of rotation, revolution, and radial motion. The core roller 30 and the side pressure roller 20 form a stable radial constraint forming system for the sidewall of the ring blank 100. Under the combined action of axial rolling force and radial constraint force, the metal material inside the ring blank 100 flows plastically in a direction to enter the core roller cavity, that is, the top material flows downward and the outer material flows inward, thus flowing steadily into the core roller cavity of the core roller 30 to form an integral internal rib structure.

[0029] Specifically, the worktable 110 is provided with a side pressure rotation drive mechanism 5 that drives the side pressure roller 20 to revolve around the ring blank 100 and a synchronous rotation drive mechanism 6 that drives the core roller 30 to revolve synchronously. The two rotation drive mechanisms work simultaneously so that the central axes of the side pressure roller 20 and the core roller 30 remain aligned throughout the forming process and are located in the same vertical plane as the central axis of the ring blank 100. This constrains and controls the inner and outer diameter dimensions of the side wall of the ring blank 100, ensuring the dimensional accuracy and stability of the ring workpiece during the forming process.

[0030] like Figures 4 to 6 As shown, the side-pressure rotation drive mechanism 5 includes an outer turntable 501 rotatably mounted on the top surface of the worktable 110 and a first drive motor 502 fixedly mounted on the bottom of the worktable 110. A first drive gear 503 is fixedly connected to the output shaft end of the first drive motor 502, and a first driven gear 504 coaxially connected to the bottom of the outer turntable 501 and meshing with the first drive gear 503. The outer turntable 501 is an annular disc, and its outer and inner edges are connected to the top surface of the worktable 110 through a first thrust bearing 505 and a second thrust bearing 506 coaxially mounted, respectively, so that the outer turntable 501 can be smoothly rotated on the worktable 110. The first driven gear 504 is an internal gear ring structure, which is fixedly connected to the bottom surface of the outer turntable 501 by bolts, and is coaxially arranged with the first thrust bearing 505 / second thrust bearing 506. The first driving gear 503 and the first driven gear 504 mesh internally and form a reduction gear pair. The first drive motor 502 is a servo motor, which can precisely control the speed output, and thus precisely control the speed of the outer turntable 501, that is, the speed of the side pressure roller 20 revolving around the ring blank 100.

[0031] The synchronous rotation drive mechanism 6 includes an inner turntable 601 rotatably mounted on the top surface of the worktable 110 and a third drive motor 602 fixedly mounted on the bottom of the worktable 110. A second drive gear 603 is fixedly connected to the output shaft of the third drive motor 602, and a second driven gear 604, meshing with the second drive gear 603, is coaxially connected to the bottom of the inner turntable 601. The inner turntable 601 is a circular disc, and its outer edge is connected to the top surface of the worktable 110 via a third thrust bearing 605 coaxially mounted, and is coaxially mounted with the outer turntable 501, so that the inner turntable 601 can be smoothly rotated on the worktable 110. The second driven gear 604 is bolted to the center of the bottom surface of the inner turntable 601 and is coaxially arranged with the third thrust bearing 605. The second driving gear 603 and the second driven gear 604 mesh externally to form a reduction gear pair. The third drive motor 602 is also a servo motor, which can precisely control the speed output, thereby precisely controlling the speed of the inner turntable 601, that is, the speed of the core roller 30 revolving around the ring blank 100, so that its speed is consistent with that of the outer turntable 501. In this way, it can be ensured that the core roller 30 set on the inner turntable 601 and the side pressure roller 20 set on the outer turntable 501 always maintain synchronous revolution around the ring blank 100, and ensure that the central axes of the side pressure roller 20 and the core roller 30 remain aligned throughout the forming process and are located in the same vertical plane as the central axis of the ring blank 100.

[0032] A first linear drive mechanism 7 for driving the radial feed of the side pressure roller is provided on the top of the side pressure rotation drive mechanism, and a side pressure rotation drive mechanism 8 for driving the rotation of the side pressure roller is provided on the first linear drive mechanism. The first linear drive mechanism 7 includes a first servo hydraulic cylinder 701 fixedly mounted on the top surface of the outer turntable 501 and a first bracket 702 connected to the output shaft end of the first servo hydraulic cylinder 701 and slidably mounted on the top surface of the outer turntable 501. A first slide rail slider assembly 703 distributed radially is fixedly connected to the top surface of the outer turntable 501 by bolts, and the first bracket 702 is fixedly connected to the top of the slider of the first slide rail slider assembly 703; a first mounting base 704 is fixedly connected to the outer edge of the top surface of the outer turntable 501 by bolts, the first servo hydraulic cylinder 701 is fixedly mounted on the first mounting base 704 and its output shaft is distributed radially, the output shaft end of the first servo hydraulic cylinder 701 is fixedly connected to the outer side surface of the first bracket 702, and the two ends of the rotating shaft of the side pressure roller 20 are rotatably mounted in the first bracket 702 by bearings and bearing covers, respectively. Thus, the first servo hydraulic cylinder 701 can drive the side pressure roller 20 to move horizontally to achieve radial feed and provide radial pressure to the side pressure roller 20, thereby achieving continuous rolling pressure on the outer surface of the ring blank 100, causing the metal material of the ring blank 100 to flow inward. The side pressure roller 20 is fed radially until its cylindrical surface is externally tangent to the outer groove wall / outer wall of the oscillating roll cavity of the clamping seat 1, so that the outer wall of the ring blank 100 is a complete cylindrical surface.

[0033] The side-pressure rotation drive mechanism 8 includes a second drive motor 801 fixedly mounted on the top of the first bracket 702, a second drive gear 802 fixedly connected to the output shaft end of the second drive motor 801, and a second driven gear 803 fixedly connected to the top of the rotating shaft of the side pressure roller 20, meshing with the second drive gear 802. A motor mounting bracket is bolted to the outer side of the top of the first bracket 702. The second drive motor 801 is fixedly mounted on the motor mounting bracket, and the second drive gear 802 is located inside the motor mounting bracket, forming a reduction gear pair with the second driven gear 803. The second drive motor 801 is also a servo motor, which can precisely control the rotation speed of the side pressure roller 20 through the gear pair, creating a speed difference between its rotation speed and its revolution speed. This allows the cylindrical surface of the side pressure roller 20 to roll (revolve) relative to the outer surface of the ring blank 100, causing the outer surface of the ring blank 100 to be sheared, thus achieving circumferential flow of metal material.

[0034] Preferably, such as Figure 7 As shown, the bottom end face of the side pressure roller 20 and the outer top end face of the clamping seat 1 are located in the same horizontal plane, and the bottom end face of the core roller 30 and the inner top end face of the clamping seat 1 are located in the same horizontal plane. In this embodiment, the outer top end face and the inner top end face of the clamping seat 1 are set to the same height, and the axial heights of the side pressure roller 20 and the core roller 30 are also the same. In this way, it can be ensured that the action positions of the side pressure roller 20 and the core roller 30 on the ring blank 100 are always consistent inside and outside, avoiding uneven force at the action position, and at the same time preventing metal material from entering between the bottom end face of the side pressure roller 20 and the outer top end face of the clamping seat 1 and between the bottom end face of the core roller 30 and the inner top end face of the clamping seat 1, ensuring the integrity of the inner and outer walls of the bottom of the formed part, and avoiding undesirable structures such as protrusions or burrs.

[0035] More preferably, when the bottom end face of the swing roller 10 is in its lowest position, the outer portion of the bottom end face rolls in contact with the top end face of the side roller 20, and the inner portion of the bottom end face rolls in contact with the top end face of the core roller 30. Similarly, this prevents metal material from entering between the bottom end face of the swing roller 10 and the top end face of the side roller 20, and between the bottom end face of the swing roller 10 and the top end face of the core roller 30, thus ensuring the integrity of the inner and outer walls of the top portion of the formed part.

[0036] A second linear drive mechanism 9 is provided on the top of the inner turntable 601 of the synchronous rotation drive mechanism 6 to drive the core roller 30 to feed radially. The second linear drive mechanism 9 has a similar structure to the first linear drive mechanism 7 and is arranged opposite to the first linear drive mechanism 7 on both sides of the side wall of the ring blank 100, which will not be described in detail here. The second linear drive mechanism 9 can drive the core roller 30 to move horizontally to achieve radial feed and provide radial back pressure to the core roller 30 (opposite to the radial pressure of the side pressure roller 20), thereby achieving continuous rolling of the inner surface of the ring blank 100 (the cylindrical surface of the core roller 30 rolls and contacts the inner wall of the ring blank 100 and rotates passively), so that the metal material of the ring blank 100 flows inward into the core roller mold cavity to form annular inner ribs. The core roller 30 is radially fed until its cylindrical surface is internally tangent to the inner wall of the groove of the clamping seat 1 / the inner wall of the oscillating rolling cavity, so that the inner wall of the ring blank 100 is a complete cylindrical surface above and below the inner diameter.

[0037] This invention also provides an envelope-roll forming process for cylindrical parts with internal ribs, using the envelope-roll forming device for cylindrical parts with internal ribs as described above. Before using the device, necessary equipment checks and mold preparations are required: check the operating status of the forming equipment, confirm that the swing roller, side roller, core roller and clamping seat are working properly, and check whether each drive mechanism, transmission mechanism and control system are in normal working condition; align and calibrate the side roller and core roller to ensure that the equipment axis is consistent, so as to ensure the stable progress of the subsequent forming process.

[0038] The forming process includes the following steps: S1. Billet preparation: Titanium alloy ring billets are prepared using hot isostatic pressing (HIP) process.

[0039] First, the pre-formed powder blank or packaged blank is placed in a HIP (High-Intensity Interval) machine and densified at 900–1200℃ and 100–150 MPa for 1–4 h. Then, under depressurization, it is cooled in the furnace to 400–500℃ and removed to obtain a dense, uniformly structured titanium alloy ring blank. Before forming, the ring blank is reheated to 900–1050℃ and held for a certain time to ensure temperature uniformity, then quickly transferred to the forming machine's working area.

[0040] S2. Installation and positioning of ring blank 100: Place the heated ring blank 100 in the clamping seat 1, and feed the side pressure roller 20 and core roller 30 radially, gradually approaching the side wall surface of the ring blank 100 until contact.

[0041] S3, Swinging roller 10 descends for loading: The swinging roller 10 descends until the end face of its bottom swinging chamber contacts the upper end face of the ring blank 100, and establishes stable axial loading conditions; the downward pressing speed of the swinging head is controlled at 1~3mm / min to avoid excessive initial impact and ensure smooth loading.

[0042] S4. Continuous oscillating forming: The oscillating pressure roller 10 oscillates continuously according to the preset oscillation angle and feeds axially at the preset feed speed to continuously oscillate and roll the ring blank 100, so that the material of the ring blank 100 produces uniform plastic deformation in the axial direction and gradually becomes stable; the rotation speed of the oscillating head is controlled at 15~40 rpm, while the axial feed speed is maintained at 3~5 mm / min.

[0043] S5. Side Pressure Roller Constraint and Radial Loading: The side pressure roller 20 rotates with preset parameters and revolves around the ring blank 100, while simultaneously performing radial feed motion, applying a continuous and stable radial clamping force to the outer surface of the ring blank 100. The rotational speed of the side pressure roller 20 is controlled at 20~60 rpm, the revolving speed at 0.5~3 rpm, and the radial feed speed at 1~2 mm / min. Throughout the forming process, the core roller 30, the side pressure roller 20, and the central axis of the ring blank 100 remain coplanar and precisely aligned in the circumferential direction, thus forming a stable radial constraint forming system.

[0044] S6. Forming of the inner rib structure: Under the combined action of axial rolling force and radial constraint force, the metal material inside the ring blank 100 undergoes directional plastic flow, and the inner metal is gradually forced into the core roller mold cavity; as the forming process continues, the metal gradually fills the core roller mold cavity and forms a stable structure, realizing the integrated plastic forming of the inner rib structure and the cylinder wall.

[0045] S7. Equipment Reset: The swing roller 10 stops swinging and moves upward to reset; the side roller 20 stops rotating and moves outward to reset; and the core roller 30 moves inward to reset.

[0046] S8. Remove the formed workpiece from the clamping seat.

[0047] After forming, the workpiece can be further processed and its performance tested: appropriate heat treatment and a small amount of finishing are performed as needed to improve dimensional accuracy and surface quality; then, samples are taken from different characteristic areas of the component for testing, and the microstructure is observed through metallographic microscopy to evaluate the forming quality and optimize the process parameters.

[0048] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An enveloping-roll forming apparatus for a cylindrical part with internal ribs, comprising a worktable, a clamping seat fixed to the top surface of the worktable, and an axial feed mechanism located above the clamping seat, wherein the ring blank to be formed is clamped at the top of the clamping seat, characterized in that: The bottom end of the axial feed mechanism is rotatably connected to a swing roller via a bending shaft, and the axial feed mechanism is equipped with a swing rotation drive mechanism that drives the bending shaft to rotate. A side pressure roller is provided on the outer side of the side wall of the ring blank, and a core roller is provided on the inner side of the side wall. The central axis of the side pressure roller, the core roller and the ring blank are located in the same vertical plane. An annular core roller cavity is opened in the outer wall of the core roller. The worktable is equipped with a side pressure rotation drive mechanism that drives the side pressure roller to revolve around the ring blank and a synchronous rotation drive mechanism that drives the core roller to revolve synchronously. The top of the side pressure rotation drive mechanism is provided with a first linear drive mechanism for driving the side pressure roller to feed radially. The first linear drive mechanism is provided with a side pressure rotation drive mechanism for driving the side pressure roller to rotate. The top of the synchronous rotation drive mechanism is provided with a second linear drive mechanism for driving the core roller to feed radially. The oscillating roller continuously rolls the top surface of the ring blank through a combination of vertical and circumferential oscillation. The side rollers continuously roll the outer surface of the ring blank through a combination of rotation, revolution, and radial motion. The core roller and the side rollers form a stable radial constraint forming system for the sidewall of the ring blank. Under the synergistic effect of axial rolling force and radial constraint force, the metal material inside the ring blank flows in a directional plastic manner into the core roller mold cavity.

2. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to claim 1, characterized in that: The side-pressure rotation drive mechanism includes an outer turntable rotatably mounted on the top surface of the worktable and a first drive motor fixedly mounted on the bottom of the worktable. The output shaft end of the first drive motor is fixedly connected to a first driving gear, and the bottom of the outer turntable is coaxially connected to a first driven gear that meshes with the first driving gear.

3. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to claim 2, characterized in that: The first linear drive mechanism includes a first servo hydraulic cylinder fixedly mounted on the top surface of the outer turntable, a first bracket connected to the output shaft end of the first servo hydraulic cylinder and slidably mounted on the top surface of the outer turntable, and a side pressure roller rotatably mounted inside the first bracket.

4. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to claim 3, characterized in that: The side pressure rotation drive mechanism includes a second drive motor fixedly mounted on the top of the first bracket, a second drive gear fixedly connected to the output shaft end of the second drive motor, and a second driven gear fixedly connected to the top of the rotating shaft of the side pressure roller and meshing with the second drive gear.

5. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to claim 1, characterized in that: The synchronous rotation drive mechanism includes an inner turntable rotatably mounted on the top surface of the worktable and a third drive motor fixedly installed at the bottom of the worktable. The output shaft of the third drive motor is fixedly connected to a second driving gear, and the bottom of the inner turntable is coaxially connected to a second driven gear that meshes with the second driving gear.

6. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to any one of claims 1 to 5, characterized in that: The bottom end face of the side pressure roller and the outer top end face of the clamping seat are located in the same horizontal plane, and the bottom end face of the core roller and the inner top end face of the clamping seat are located in the same horizontal plane.

7. The envelope-roll forming apparatus for cylindrical parts with internal ribs according to claim 6, characterized in that: When the bottom end face of the swing roller is in its lowest position, the outer part of the bottom end face rolls in contact with the top end face of the side roller, and the inner part of the bottom end face rolls in contact with the top end face of the core roller.

8. An enveloping-roll forming process for a cylindrical part with internal ribs, using the enveloping-roll forming apparatus for a cylindrical part with internal ribs as described in any one of claims 1 to 7, characterized in that, Includes the following steps: The ring blank was prepared by hot isostatic pressing. The heated ring blank is placed in the clamping seat, and the side pressure roller and core roller are fed radially, gradually approaching the side wall surface of the ring blank until they contact each other; The oscillating roller descends to the bottom of its oscillating grinding chamber end face, which contacts the upper end face of the ring billet and establishes stable axial loading conditions; The oscillating roller oscillates continuously at a preset oscillation angle and feeds axially at a preset feed speed, continuously rolling and loading the ring blank. The ring blank material undergoes uniform plastic deformation in the axial direction and gradually flows stably. The side pressure roller rotates on its own axis and revolves around the ring blank with preset parameters, and is superimposed with radial feed motion to apply a continuous and stable radial clamping force to the outer surface of the ring blank. The core roller, the side pressure roller and the central axis of the ring blank always remain coplanar. Under the combined action of axial rolling force and radial constraint force, the metal material inside the ring blank undergoes directional plastic flow, and the inner metal is gradually forced into the core roller mold cavity until the metal gradually fills the mold cavity and forms a stable structure. The oscillating pressure roller stops oscillating and moves upward to reset; the side pressure roller stops rotating and moves outward to reset; the core roller moves inward to reset. Remove the formed workpiece from the clamping seat.

9. The envelope-roll forming apparatus and process for cylindrical parts with internal ribs according to claim 1, characterized in that: The oscillating speed of the oscillating roller is 15~40 rpm, and the axial feed speed is 3~5 mm / min.

10. The envelope-roll forming apparatus and process for cylindrical parts with internal ribs according to claim 1, characterized in that: The rotational speed of the side pressure roller is 20~60 rpm, the revolution speed is 0.5~3 rpm, and the radial feed speed is 1~2 mm / min.

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