Anti-twisting bending forming process for super-large-diameter positive turning frame with straight edge and acute angle

Abstract

The invention provides an anti-twisting bending forming process for a super-large-diameter acute-angle forward turning frame with straight edges. The anti-twisting bending forming process comprises the following steps that S1, a sectional material frame raw material is set; and S2, roll bending forming is conducted on the profile frame on the basis of a four-axis anti-twisting horizontal numerical control profile roll bending machine with a rotating disc. The method has the beneficial effects that a roll bending forming process is adopted for replacing a stretch bending forming process for the oversized-diameter straight-edge acute-angle forward-turning profile frame, the investment of a large-diameter stretch bending die can be reduced, the size of one set of rolling wheels is small, profile frame parts with different diameters can be rolled and bent, and therefore the die manufacturing and storage cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of anti-twisting bending forming of a positive turning frame, and in particular relates to an anti-twisting bending forming process of a positive turning frame with an ultra-large diameter and straight edges and sharp angles. Background Art

[0002] The profile frame is an important component of the launch vehicle. The diameter of the launch vehicle is large, and the required profile frame diameter is also large. The existing profile frame diameter is a semicircle of 2-5 meters. The profile frame diameter of the new generation of launch vehicle fairing is 6.4 meters. The diameter will be larger in the future. Most of the profile frames are formed by stretching and bending, from straight materials to semicircles. Stretch-bending forming has many disadvantages. The mold diameter is large and the cost is high. Soft material stretching, heating and quenching methods are required. For profile frames with larger diameters, they exceed the limit of the bending radius of the equipment and cannot be stretched and bent into a semicircle. They can only be stretched and bent at 90° or smaller bending angles. When multiple sections of the frame are riveted, the interfaces are mostly unstable.

[0003] Most of the profile frames of current models of launch vehicles are asymmetric profiles formed by stretching and bending. There are many disadvantages in stretching and bending. The diameter of the launch vehicle profile frame parts is very large, requiring a large-diameter stretching and bending mold, which has high mold costs. The diameter of the launch vehicle is developing in a large diameter trend. For profile frames with larger diameters, the limit of the bending radius of the equipment is exceeded and they cannot be stretched and bent into a semicircle. They can only be stretched and bent into multiple sections with small bending angles. When the multiple sections are riveted, the interfaces are often unstable. An ultra-large diameter sharp-angle profile frame uses a high-cost stretching and bending mold, needs to be split into 90°, has poor stability, and needs to be stretched and bent by heating and quenching soft materials. After quenching, the deformation is large and the stretching and bending forming accuracy is poor. Conventional rolling bending is prone to uneven force and leaning to one side, the cross-section is twisted, and the end part is twisted and warped, and qualified parts cannot be rolled out. Specifically:

[0004] An extra-large diameter straight-edge sharp-angle profile frame, with a semicircular outline, a diameter of 6.4 meters, an acute-angle cross-section, an angle of 64°, a short straight edge at the corner, a length of 15mm, a thinner bevel thickness of 4mm, a bottom length of 51mm, and a thickness of 5mm. Parts such as Figure 1 shown.

[0005] At present, the stretch-bending forming method is adopted. The mold cost is high, and a set of molds costs more than 500,000 yuan. It needs to be split into 90° stretch-bending forming, and the stability is poor. The raw material is 7A09 aluminum alloy, and the O-state soft material stretch-bending heating treatment quenching method is required. After quenching, the deformation is large, the stretch-bending forming accuracy is poor, and the cross-sectional distortion will occur, resulting in poor part surface accuracy. Deformation such as Figure 2 shown.

[0006] Roll bending can be used to bend a semicircle of 180°, and the rolling bending mold is small in size and low in cost. A set of rolling bending molds costs less than 100,000 yuan. However, conventional rolling bending methods are suitable for symmetrical cross-section profiles. For asymmetrical cross-section sharp-angle profiles, rolling bending is prone to uneven force and leaning to one side, causing the cross-section to twist and the end to twist, making it impossible to roll out qualified parts. Summary of the invention

[0007] In view of this, the present invention aims to propose an anti-twisting bending forming process for an ultra-large diameter, straight-edge, sharp-angled positive frame, so as to solve the problem that the launch vehicle profile frame adopts the stretch bending forming method, the stretch bending mold used is large in size and high in cost, and the profile frame with a larger diameter exceeds the limit of the bending radius of the equipment and cannot be stretched into a semicircle, and can only be stretched and bent into multiple sections with small bending angles. During riveting, the interface has poor stability and it is necessary to adopt the soft material stretch bending, heating and quenching method. After quenching, the deformation is large and the stretch bending forming accuracy is poor. At the same time, the conventional roll bending forming section of the asymmetric sharp-angle profile frame is easy to twist. The anti-twisting bending forming process is adopted, and the rolling process parameters are reasonably designed to produce profile frame parts with surface dimensions that meet the requirements.

[0008] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0009] A torsion-proof bending forming process for a super-large diameter straight-edge sharp-angle positive turning frame comprises the following steps:

[0010] S1. Set the raw materials of the profile frame;

[0011] S2, rolling and bending the profile frame based on a four-axis horizontal CNC profile rolling and bending machine with a turntable to prevent twisting;

[0012] In step S1, the raw material of the profile frame is 7A09 aluminum alloy, and T6 hard aluminum alloy is used for roll bending. The profile frame is directly roll-bent after blanking, and a 1200 mm margin is added during blanking, and the margin is cut off after rolling.

[0013] Furthermore, in step S2, the four-axis horizontal CNC profile rolling bending machine with a turntable anti-twist is provided with an anti-twist disk. During the part rolling and bending process, the profile material is inserted into the corresponding mold of the turntable. By setting the rotation angle of the turntable, the workpiece is driven to rotate. The turntable can move up and down in the vertical direction to adjust the twisting of the part end.

[0014] Furthermore, in step S2, the roll bending forming only adjusts the radius size, and the part is in a twisted shape after rolling. At this time, it is necessary to eliminate the torsion of the part and give the part a reverse torsion force. The specific settings include:

[0015] The rotation angle rule is to rotate in the opposite direction of the bevel of the profile frame, that is, to rotate counterclockwise at a negative angle. The profile frame is rolled and bent in multiple passes, with each pass twisting at a different angle. The rotation angle rule is to greatly increase the rotation angle in the first few passes, and then reduce the rotation angle slightly in the next few passes. This can correct the distortion of the profile frame and improve the forming accuracy of the profile surface.

[0016] Further, in step S2, the rolling bending passes range from 4 to 16 times, the maximum rotation angle range of the first few passes is 20° to 26°, and the final rotation angle range of the last few passes is 13° to 17°.

[0017] Furthermore, in step S2, while the angle of each rolling and bending is rotated, the turntable drives the parts to move up and down to increase the angle correction force. The up and down movement rule of the turntable is the same as the angle rotation rule. The turntable moves downward in the first few rolling and bending passes, and then moves upward in the next few rolling and bending passes.

[0018] An electronic device comprises a processor and a memory which is in communication with the processor and is used to store instructions executable by the processor, wherein the processor is used to execute the anti-twisting bending forming process of an ultra-large diameter straight-edge sharp-angle positive-turn frame.

[0019] A server includes at least one processor and a memory connected to the processor in communication, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to enable the at least one processor to perform the super-large diameter straight-edge sharp-angle positive frame anti-twisting bending forming process.

[0020] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the super-large diameter straight-edge sharp-angle positive-turn frame anti-twist bending forming process is realized.

[0021] Compared with the prior art, the anti-twist bending forming process of the super-large diameter straight-edge sharp-angle positive turning frame described in the present invention has the following advantages:

[0022] (1) The present invention discloses a torsion-proof bending forming process for an ultra-large diameter straight-edge and sharp-angled positively turned frame. The ultra-large diameter straight-edge and sharp-angled positively turned profile frame adopts a rolling forming process instead of a stretching forming process, which can reduce the investment in large-diameter stretching and bending dies. A set of rollers is small in size and can bend profile frame parts of different diameters, thereby reducing the cost of mold manufacturing and storage.

[0023] (2) The present invention discloses a process for anti-twisting bending of an ultra-large diameter profile with a straight edge and sharp angle. The ultra-large diameter profile can be continuously bent by rolling, and the bending radius and length are not limited by the equipment. This solves the problem that the large diameter profile can only be bent by multiple sections with small bending angles when it exceeds the limit of the bending radius of the equipment and has poor interface stability during riveting.

[0024] (3) The invention discloses a torsion-proof bending forming process for an ultra-large diameter straight-edge and sharp-angled positively turned frame. The ultra-large diameter straight-edge and sharp-angled positively turned profile frame can be directly rolled and formed by T6 hard material, thus saving the heat treatment and quenching process of the stretching and bending forming, reducing the production cost, reducing the production cycle by 30%, and improving the production efficiency.

[0025] (4) The present invention discloses a process for anti-twisting bending of an ultra-large diameter straight-edge and sharp-angled positive frame, which adopts a rolling process method in which the cross-sectional angle of one end of the profile is rotated as a whole during the rolling process, while the height of the profile at one end is moved and the downward pressure value is increased. The process parameters of first greatly increasing the rotation angle, then slightly reducing the rotation angle, while moving the height of the profile at one end, first moving downward, and then moving upward can effectively solve the problem of profile rolling distortion, and successfully roll out profile frame parts with qualified dimensions and straight edges and sharp angles, with high part forming accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 It is a schematic diagram of parts in the prior art;

[0028] Figure 2 It is a schematic diagram of part deformation in the prior art;

[0029] Figure 3 A schematic diagram of a turntable according to an embodiment of the present invention;

[0030] Figure 4 A schematic diagram of disk correction according to an embodiment of the present invention;

[0031] Figure 5 The figure is a schematic diagram of the process flow described in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0033] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0036] like Figures 3 to 5 As shown, a torsion-proof bending forming process of an extra-large diameter straight-edge sharp-angle positive-flip frame is used. The raw material of the profile frame is 7A09 aluminum alloy, and the roll-bending forming adopts T6 hard aluminum alloy. It is directly roll-bent after cutting. A 1200mm margin is added during cutting, and the margin is cut off after rolling.

[0037] The rolling and bending adopts a four-axis horizontal CNC profile rolling and bending machine with a turntable to prevent twisting. The equipment has an anti-twist plate. During the rolling and bending process of the part, the profile material is inserted into the corresponding mold of the turntable. By setting the turntable to rotate a certain angle, the workpiece is driven to rotate. The turntable can move up and down in the vertical direction to adjust the twisting of the part end. The schematic diagram of the turntable rotation and movement is shown as follows Figure 3 shown.

[0038] The profile adopts the normal rolling method, that is, only the radius size is adjusted. After rolling, the part is twisted and twisted, so the torsion of the part must be eliminated and a reverse torsion force must be applied to the part. Through multiple tests and adjustment of process parameters, a method of rotating the cross-section angle of the profile during the rolling process of this type of acute-angle profile has been studied. The rotation angle rule is to rotate in the opposite direction of the profile bevel, that is, counterclockwise negative angle rotation. Due to the long arc length of the profile, it needs to be rolled in multiple passes, and each pass is twisted at a different angle. The rotation angle rule is to greatly increase the rotation angle in the first few passes, and then reduce the rotation angle slightly in the next few passes. This can well correct the distortion of the profile and improve the forming accuracy of the profile. The rolling pass range is 4-16 times. The fewer the times, the higher the efficiency. The maximum rotation angle range of the first few passes is 20°-26°, and the final rotation angle range of the next few passes is 13°-17°. While the angle is rotated in each rolling process, the turntable drives the parts to move up and down to increase the angle correction force. The up and down movement pattern of the turntable is the same as the angle rotation pattern. The turntable moves downward in the first few rolling processes and then moves upward in the next few rolling processes.

[0039] For this profile frame with straight edges and sharp angles, the rolling forming process parameters are shown in Table 1, and the rolling turntable correction is as follows: Figure 4 shown.

[0040] Table 1 Anti-twist rolling forming process parameters

[0041]

[0042] As can be seen from the table, the first three rolling bends first greatly increase the rotation angle, the maximum rotation angle reaches -23°, and the last three rolling bends slightly reduce the rotation angle, and the final rotation angle reaches -15°. While rotating the angle at each rolling bend, the turntable drives the part to move up and down to increase the angle correction force. The up and down movement rule of the turntable is the same as the angle rotation rule. The first three rolling bends first move downward to -3mm, and then move upward to 2mm in the last three rolling bends. While rolling each time, the downward pressure value is increased to gradually reduce the radius of the part. The downward pressure value increases by the same value in the first four times, all 2, and the increase in the last two times is smaller than the first four times, both 0.5. The process parameters of each rolling bend are shown in the table.

[0043] By rotating the profile cross-section angle and moving one end of the profile up and down and adjusting the radius size during each rolling process, the radius size, bottom edge flatness size and bevel angle size of the part meet the technical index requirements after 6 rolling bendings. The radius deviation is 0.8mm (required ≤1.5mm), the gap between the bottom plane flatness and the platform is 0.6mm (required ≤0.8mm), and the gap between the bevel angle and the right-angle ruler is 0.4mm (required ≤0.8mm).

[0044] The present invention proposes an electronic device, comprising a processor and a memory connected to the processor for storing executable instructions, wherein the processor is used to execute the super-large diameter straight-edge sharp-angle positive-turn frame anti-twisting bending forming process.

[0045] The present invention proposes a server, comprising at least one processor and a memory communicatively connected to the processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to enable the at least one processor to perform the super-large diameter straight-edge and sharp-angle positive frame anti-twisting bending forming process.

[0046] The present invention provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the super-large diameter straight-edge sharp-angle positive turning frame anti-twisting bending forming process is realized.

[0047] The invention discloses a rotating disk anti-twisting hard material rolling and bending forming process for a super-large diameter straight-edge sharp-angle positive-turning profile frame, and adopts a rolling and bending process method in which one end of the profile cross-section angle is integrally rotated and the other end of the profile height is moved and the downward pressure value is increased during the rolling and bending process.

[0048] The process parameters of the turntable anti-twisting hard material rolling bending forming of the super-large diameter straight-edge sharp-angle positive-turning profile frame of the present invention are as follows: the rolling bending parameter rule is counterclockwise rotation, first greatly increasing the rotation angle, then slightly reducing the rotation angle, and at the same time moving the height of one end of the profile, first moving downward, and then moving upward.

[0049] Advantages of the present invention:

[0050] (1) The large diameter straight edge and sharp angle positive turning profile frame adopts the rolling forming process instead of the stretch bending forming process, which can reduce the investment of large diameter stretch bending molds. A set of rollers is small in size and can roll profile frame parts of different diameters, thereby reducing the mold manufacturing and storage costs.

[0051] (2) The roll bending of ultra-large diameter profiles can be continuously bent, and the bending radius and length are not limited by the equipment. This solves the problem that the large diameter profile stretch bending exceeds the limit of the equipment bending radius and can only be divided into multiple sections with small bending angles for stretch bending. During riveting, the interface often has poor stability.

[0052] (3) Extra-large diameter straight-edge and sharp-angled profile frames can be directly rolled and formed using T6 hard material, saving the heat treatment and quenching process of stretch bending, reducing production costs, reducing production cycles by 30%, and improving production efficiency.

[0053] (4) A rolling bending process method is adopted in which the profile cross-section angle is rotated as a whole at one end during the rolling process, and the profile height at one end is moved and the downward pressure value is increased. The process parameters are firstly greatly increased in rotation angle, then slightly decreased in rotation angle, and the profile height at one end is moved downward and then upward. This can effectively solve the problem of profile rolling distortion, and successfully roll out profile frame parts with straight edges and sharp angles of qualified dimensions, with high part forming accuracy.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A process for forming a super-large diameter straight-edge sharp-angle positive frame anti-twist bending, characterized in that: The following steps are involved: S1. Set the profile frame raw materials; S2, rolling and bending the profile frame based on a four-axis horizontal CNC profile rolling and bending machine with a turntable to prevent twisting; In step S1, the raw material of the profile frame is 7A09 aluminum alloy, and T6 hard aluminum alloy is used for roll bending. The profile frame is directly roll-bent after blanking, and a 1200 mm margin is added during blanking, and the margin is cut off after rolling.

2. According to claim 1, a super-large diameter straight-edge sharp-angle positive turning frame anti-twist bending forming process is characterized by: In step S2, the four-axis horizontal CNC profile rolling bending machine with a turntable anti-twist is provided with an anti-twist disk. During the part rolling process, the profile material is inserted into the corresponding mold of the turntable. By setting the rotation angle of the turntable, the workpiece is driven to rotate. The turntable can move up and down in the vertical direction to adjust the twisting of the part end.

3. The process for forming a super-large diameter straight-edge sharp-angle positive turning frame anti-twist bending according to claim 2, characterized in that: In step S2, the roll bending only adjusts the radius size. After the part is rolled, it is twisted and twisted. At this time, it is necessary to eliminate the torsion of the part and give the part a reverse torsion force. The specific settings include: The rotation angle rule is to rotate in the opposite direction of the bevel of the profile frame, that is, to rotate counterclockwise at a negative angle. The profile frame is rolled and bent in multiple passes, with each pass twisting at a different angle. The rotation angle rule is to greatly increase the rotation angle in the first few passes, and then reduce the rotation angle slightly in the next few passes. This can correct the distortion of the profile frame and improve the forming accuracy of the profile surface.

4. The process for forming a super-large diameter straight-edge sharp-angle positive turning frame for anti-twisting bending according to claim 3 is characterized in that: In step S2, the rolling bending passes range from 4 to 16, the maximum rotation angle range of the first few passes is 20° to 26°, and the final rotation angle range of the last few passes is 13° to 17°.

5. The process for forming a super-large diameter straight-edge sharp-angle positive turning frame for anti-twisting bending according to claim 4, characterized in that: In step S2, while the turntable rotates the angle at each rolling bending pass, the turntable drives the part to move up and down to increase the angle correction force. The turntable moves up and down in the same manner as the angle rotation. The turntable moves downward in the first few rolling bending passes and then moves upward in the next few rolling bending passes.

6. An electronic device, comprising a processor and a memory connected to the processor for storing instructions executable by the processor, characterized in that: The processor is used to execute the anti-twisting bending forming process of the super-large diameter straight-edge sharp-angle positive frame as described in any one of claims 1-5 above.

7. A server, characterized in that: It includes at least one processor and a memory communicatively connected to the processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor so that the at least one processor performs the anti-twisting bending forming process of an ultra-large diameter straight-edge sharp-angle positive frame as described in any one of claims 1-5.

8. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it implements the anti-twisting bending forming process of an ultra-large diameter straight-edge sharp-angle positive frame as described in any one of claims 1 to 5.

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