Multi-angle stretch bending method for first rib profile of civil wing

Abstract

The invention discloses a multi-angle stretch bending method for a first rib profile of a civil wing, belongs to the technical field of stretch bending of wing profiles, is used for stretch bending of wing profiles, and comprises the following steps: carrying out solution quenching treatment on an extruded profile, then carrying out stretch bending, recording quenching completion time m1, and mounting a stretch bending device; the stretch bending device is positioned, the sectional material is fixed, the sectional material is straightened, the mold is positioned, the sectional material is stretch-bent, stretch-bent and shaped, the clamping head A and the clamping head B tilt downwards by 0.1 degree to start discharging, the stretching force is unloaded, the clamping head A and the clamping head B are opened, the stretching cylinder retreats until the sectional material completely retreats from the clamping head A and the clamping head B, the stretching force unloading time is recorded as m2, and finally the sectional material is cut. Compared with the prior art, the stretching, straightening and stretch-bending device can stretch, straighten and stretch-bend a long profile, the influence on the mechanical performance of the profile is reduced to the minimum, the problem that the precision of a large-size profile after being stretched is low is solved, the stretch-bending radian and the outline of the obtained first rib profile are within the design deviation range, the product application requirement is met, and the yield of the profile is increased.

Description

Technical Field

[0001] The invention discloses a multi-angle bending method for a No. 1 rib profile of a civil wing, and belongs to the technical field of bending of wing profiles. Background Art

[0002] As the application fields of aluminum profiles gradually expand, the requirements for the shapes of aluminum profiles are also gradually increasing. Stretch bending is a way of further processing aluminum profiles, and the resulting bent parts are widely used in aviation, aerospace, automobiles, high-speed rail and other fields. For example, in the civil (aviation, high-speed rail) field, many skeleton parts use profile frames, such as the reinforcement ribs and skeletons of the fuselage and wings, train head supports, curved window frames, curved frame skeletons, etc.

[0003] Aluminum profile bending is an important forming process in industrial production. It is used to manufacture variable curvature extruded profile bent parts with large size, high requirements for shape accuracy and large relative bending radius. The characteristics of the bent parts are relatively large curvature radius, relatively large springback, and curvature changes along the axial direction. The existing mature aluminum profile bending technology is mainly aimed at the bending of low-strength aluminum alloys such as 5 series and 6 series or small-section profiles, and is mainly used in construction, daily necessities and other fields. Due to the low strength of 5 series and 6 series alloys and the small cross-section of the bent profile, the bending process is relatively simple and cannot meet the bending requirements of high-strength and high-toughness profiles in the aviation field; general bending technology usually uses a press or a bending machine for bending and forming, the bending angle is single, and the profile length is limited, which cannot meet the requirements of segmented bending of the No. 1 rib.

[0004] The No. 1 rib upper edge strip of a civil aircraft wing is an important wing structural component. It has a complex double-cross cross-section and high density. It is used to connect the long spars of the wing. There are strict requirements on the size and bending angle of the No. 1 rib after bending. In addition, the aircraft wing is symmetrical on the left and right, so the bending structural components required at the same position are two bending structural components with the same angle but opposite directions.

[0005] In the existing technology, it is usually necessary to replace the stretching and bending mold to achieve the angular symmetry of the left and right structural parts. The invention patent application with publication number CN115446167A discloses a bending method for a long stringer on a civil aircraft wing. The bending is achieved by adjusting the height of workbench A, workbench B, and workbench C and adjusting the rotation angle of chuck A and chuck B. However, there is only one bending point on the profile of the patent. The stretching and bending method cannot process an arc-shaped profile, and the profile structure is single. The profile bending and bending shaping process is relatively simple, and the bending force is small, which cannot meet the requirements of multi-angle stretching and bending of large materials with complex cross-sections. The invention patent application with the publication number CN106363083A discloses a flexible bending die and a processing method for rapidly forming large curvature profile parts. It adopts multiple adjustable telescopic mechanisms to realize flexible processing of profile parts with different curvatures without the need to manufacture a large number of special molds. However, it can only be used for small profiles. For large-section profiles, a large tensile force is required. The telescopic mechanism is prone to failure and cannot achieve the required deformation. In addition, the equipment needs to be installed with multiple hydraulic devices, and the equipment cost is high. It can only process profiles with simple structures. The utility model patent with the announcement number CN206662069U discloses a bending die for bending and forming a T-hook profile. A movable core mold connected to the upper mold is used to press and form the T-hook surface of the profile during the bending and forming of the T-hook profile. However, the device generates a large amount of internal stress at the compression bending position through compression molding, while the state of other positions of the profile remains unchanged. The deformation of the entire profile is uneven. In the subsequent use process, the bending position is likely to break, which poses certain safety hazards.

[0006] The invention patent application with publication number CN111411273A discloses a 7 series aluminum alloy profile for the No. 1 rib of a civil aircraft and its preparation method. Figure 2 Disclosed is a rib profile structure (as shown in the accompanying drawings of the present invention) Figure 8 As shown in the figure, the present invention uses the same No. 1 rib profile, and on this basis, improves the mold and studies the stretch-bending method. Summary of the invention

[0007] The purpose of the present invention is to provide a multi-angle bending method for a No. 1 rib profile of a civil wing, so as to solve the problems of insufficient deformation and uneven deformation of the wing profile in the prior art.

[0008] A multi-angle bending method for a No. 1 rib profile of a civil wing is provided, wherein a bending device is used for bending, wherein the bending device comprises a stretching machine and a bending mechanism, wherein the stretching machine and a bending die are used in combination, wherein the bending die is located on a central platform of the stretching machine, wherein the bending die comprises a combined die A and a die B, wherein the die A and the die B are combined to form a through groove A, wherein a clamp A and a clamp B having the same structure are used to clamp the No. 1 rib profile at both ends thereof, respectively, and the bending process comprises:

[0009] s1, preparation work, after solution quenching treatment of the extruded profile, stretch and bend it, record the quenching completion time m1, and install the stretch and bending device;

[0010] s2, positioning of the stretch bending device, adjusting the distance between chuck A and chuck B to 12000mm, the central platform is located between chuck A and chuck B, and the distance between chuck A and chuck B and the central platform is 6000mm;

[0011] s3, profile fixation, using equal length soft slings, the crane cooperates with the hoist to lift the profile steadily, so that the profile is located above the central platform, and the clamps A and B of the stretching machine clamp and fix the two ends of the profile;

[0012] s4, straighten the profile. After the two ends of the profile are clamped and fixed, chuck A and chuck B are rotated back to horizontal, and tensile force is applied to chuck A and chuck B;

[0013] s5, mold positioning, adjust the lifting device, so that the height of the central platform rises to the point where the arc top of the bending mold contacts the bottom of the profile, and the bottom of the profile enters the through groove A of the bending mold, and the initial height of the central platform is recorded as 0mm;

[0014] s6, profile bending, start bending and stretching, and the stretching deformation is controlled between 1.7% and 2.5%;

[0015] s7, stretching and bending to finalize. After s6 stretching and bending is completed, the height of the central platform is raised step by step and the pitch angles of chuck A and chuck B are adjusted to make the bottom of the profile fit with the through groove A at the top of the arc of the stretching and bending die;

[0016] s8, unloading, chuck A and chuck B tilt downward 0.1°, unloading the tensile force, opening chuck A and chuck B, and the stretching cylinder retreats until the profile is completely out of chuck A and chuck B, unloading is carried out, and the tensile force unloading time is recorded as m2. The time of the profile bending process is controlled to be m1-m2<3h, where h is hours. Start the crane to transport the bent No. 1 rib profile to the rack and lay it flat. Use the detection arc template to check the curvature deviation of the profile outer contour, and return the mold workbench position to zero;

[0017] s9, cutting the profile, sawing the profile of s8, cutting and scrapping the bent part formed by the contact between the profile and the chuck A and the chuck B, leaving part of the profile between the central platform and the chuck A or the chuck B, and obtaining the bent profile.

[0018] s6 includes:

[0019] A1, the central platform rises from the initial position 0mm, the initial rising height is 373mm, the lifting speed of the central platform is 6mm / s-8mm / s, until the bottom of the profile contacts the arc top of the bending die, and the straightening force is 180t;

[0020] A2, the central platform continues to rise to 570mm, all the profiles enter the bending die, the bottom of the profile enters the through slot A, the bottom surface of the reinforcement rib A and the bottom surface of the reinforcement rib C contact with the bottom surface of the through slot B, the bottom surface of the reinforcement rib B and the bottom surface of the reinforcement rib D contact with the bottom surface of the through slot C, the profile is supported and bent, and the straightening force is 360t.

[0021] s7 includes:

[0022] B1, keep the central platform height at 570mm, and at the same time increase the conjugate pitch of chuck A and chuck B from 0° to 5°. After the pitch is completed, the central platform continues to rise to 1034mm, and the straightening force is 439t-445t, so that the profile fits the bending die;

[0023] B2, keep the central platform height at 1034mm, and at the same time increase the conjugate pitch of chuck A and chuck B from 5° to 7°. After the pitch is completed, the central platform continues to rise to 1128mm, and the straightening force is 463t-479t;

[0024] B3, keep the central platform height at 1128mm, and at the same time increase the conjugate pitch of chuck A and chuck B from 7° to 10°. After the pitch is completed, the central platform continues to rise to 1293mm, and the straightening force is 486t-504t;

[0025] B4, keep the central platform height at 1293mm, and at the same time increase the conjugate pitch of chuck A and chuck B from 10° to 13°. After the pitch is completed, the central platform continues to rise to 1427mm, and the straightening force is 516t-532t;

[0026] B5, keep the central platform height at 1427mm, and at the same time increase the conjugate pitch of chuck A and chuck B from 13° to 16°. After the pitch is completed, the central platform continues to rise to 1600mm, and the straightening force is 574t-589t.

[0027] The stretching machine is a 2000T stretching machine. The clamping force of chuck A and chuck B on the profile is 150t. The angular deviation between adjacent partings that make up mold A is less than ±0.01°, the angular deviation between adjacent partings that make up mold B is less than ±0.01°, and the angular deviation between the bending mold and the straight line between chuck A and chuck B is less than ±0.02°.

[0028] The stretch-bending die is arranged along the length direction of the central platform and the top surface is an upwardly convex arc surface. Die A and die B are combined to form through grooves B and through grooves C. The width of through groove A is smaller than the width of through groove B, and the width of through groove B is smaller than the width of through groove C. The top of through groove A is connected to the bottom surface of through groove B, and the top of through groove B is connected to the bottom surface of through groove C. Through grooves A, through grooves B and through grooves C extend along the length direction of the central platform.

[0029] The No. 1 rib profile includes a central plate extending along the length direction. On the cross-section of the No. 1 rib profile, the central plate includes a main body and an extension part. The extension part is arranged at the top and bottom of the main body. Four reinforcing ribs are connected to the main body. Reinforcing rib A and reinforcing rib B are located on the same side of the main body, and reinforcing rib C and reinforcing rib D are located on the other side of the main body. Reinforcing rib A and reinforcing rib C correspond in the horizontal direction, and reinforcing rib B and reinforcing rib D correspond in the horizontal direction. The vertical length of reinforcing rib A is shorter than that of reinforcing rib C, and the vertical length of reinforcing rib B is shorter than that of reinforcing rib D. Reinforcing rib A and reinforcing rib C are arranged at the bottom of reinforcing rib B and reinforcing rib D.

[0030] The cross section of mold A includes four steps from bottom to top, and the cross section of mold B includes three steps from bottom to top.

[0031] The riser surface of the first step of mold A fits with the lower half riser surface of the first step of mold B;

[0032] A through groove A is formed between the kick surface of the second step of mold A and the upper half kick surface of the first step of mold B;

[0033] A through groove B is formed between the riser surface of the third step of mold A and the riser surface of the second step of mold B;

[0034] A through groove C is formed between the riser surface of the fourth step of mold A and the riser surface of the third step of mold B.

[0035] The through groove A clamps the extension of the bottom of the central plate, the through groove B clamps the reinforcing rib A and the reinforcing rib C, and the through groove C clamps the reinforcing rib B and the reinforcing rib D;

[0036] The tread of the first step of mold A abuts against the end of the extension of the bottom of the central plate, and the riser of the second step of mold A and the riser of the first step of mold B clamp the extension of the bottom of the central plate from both sides;

[0037] The tread of the second step of mold A abuts against the bottom of reinforcing rib A, the riser of the third step of mold A abuts against the end of reinforcing rib A, the tread of the first step of mold B abuts against the bottom of reinforcing rib C, and the riser of the second step of mold B abuts against the end of reinforcing rib C;

[0038] The tread of the third step of mold A abuts against the bottom of reinforcing rib B, the riser of the fourth step of mold A abuts against the end of reinforcing rib B, the tread of the second step of mold B abuts against the bottom of reinforcing rib D, and the riser of the third step of mold B abuts against the end of reinforcing rib D.

[0039] When the chuck A and the chuck B clamp the No. 1 rib profile, six inserts with anti-slip grooves are arranged around the No. 1 rib profile. The six inserts fill the gaps of the No. 1 rib profile and form a rectangle together with the No. 1 rib profile on the cross section.

[0040] Compared with the prior art, the present invention has the following beneficial effects: the present invention can stretch, straighten and bend longer profiles, thereby minimizing the impact on the mechanical properties of the profiles, solving the problem of low drawing precision of large-size profiles, and the bending curvature and outer contour of the obtained No. 1 rib profile are within the design deviation, meet product application requirements, and improve the profile yield rate. The method of the present invention has the advantages of high yield and high precision of the No. 1 rib profile; the present invention breaks through the yield strength in the stretching process, causes the profile to undergo plastic deformation, the overall deformation of the bent profile is relatively uniform, there is no local work hardening, and heavy-duty profiles with large cross-sections that need to be deformed can be bent; the present invention bends the No. 1 rib profile on a symmetrical mold, so the bent structural parts at the same position have the same outer contours and opposite directions, ensuring that the same batch of bent profiles have symmetrical structures; the bending time is within 3 hours after quenching, and the profile does not need to be heated during the bending process, thereby reducing the performance impact and profile deformation caused by aging strengthening caused by bending; using the specific mold of the present invention, the mold forms a specific curvature along the length direction, and the mold is composed of a plurality of mold blocks. The bending method of the present invention is used in conjunction with the mold of the present invention to ensure the shape and position dimensions of the profile, and can ensure that the outer contour of the profile is within the specified deviation, thereby improving the qualified rate of the product of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is the cross-section diagram of the profile;

[0042] Figure 2 This is a schematic diagram of the structure of rib profile No. 1;

[0043] Figure 3 This is a cross-sectional view of the profile when used in conjunction with the stretch-bending die;

[0044] Figure 4 This is the structural diagram of the No. 1 rib profile and the stretch-bending die;

[0045] Figure 5 This is a diagram of the use of inserts and profiles;

[0046] Figure 6 This is the arc test sample for the left side bending profile of the No. 1 rib profile;

[0047] Figure 7 This is the arc test sample for the right side bending profile of the No. 1 rib profile;

[0048] Figure 8 It is a No. 1 rib profile in the prior art.

[0049] The figure marks include: 1-central platform, 2-mold A, 3-mold B, 4-through groove A, 5-through groove B, 6-through groove C, 7-horizontal plate, 8-reinforcement rib A, 9-reinforcement rib B, 10-reinforcement rib C, 11-reinforcement rib D, 12-chuck A, 13-chuck B, 14-embed A, 15-embed B, 16-embed C, 17-embed D, 18-embed E, 19-embed F, 20-inner arc, 21-outer arc. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] A multi-angle bending method for a No. 1 rib profile of a civil wing is provided, wherein a bending device is used for bending, wherein the bending device comprises a stretching machine and a bending mechanism, wherein the stretching machine and a bending die are used in combination, wherein the bending die is located on a central platform 1 of the stretching machine, wherein the bending die comprises a combined die A2 and a combined die B3, wherein a through groove A4 is formed after the die A2 and the die B3 are combined, and a clamp A12 and a clamp B13 having the same structure are used to clamp the No. 1 rib profile at both ends respectively, and the bending process comprises:

[0052] s1, preparation work, after solution quenching treatment of the extruded profile, stretch and bend it, record the quenching completion time m1, and install the stretch and bending device;

[0053] s2, positioning the bending device, adjusting the distance between the chuck A12 and the chuck B13 to 12000 mm, the central platform 1 is located between the chuck A12 and the chuck B13, and the distance between the chuck A12 and the chuck B13 and the central platform 1 is 6000 mm;

[0054] s3, profile fixation, using soft slings of equal length, the crane cooperates with the hoisting to lift the profile steadily, so that the profile is located above the central platform 1, and the clamps A12 and B13 of the stretching machine clamp and fix the two ends of the profile;

[0055] s4, straighten the profile. After the two ends of the profile are clamped and fixed, the chuck A12 and the chuck B13 are rotated horizontally, and a tensile force is applied to the chuck A12 and the chuck B13;

[0056] s5, mold positioning, adjust the lifting device, so that the height of the central platform 1 rises to the point where the arc top of the bending mold contacts the bottom of the profile, and the bottom of the profile enters the through groove A4 of the bending mold, and the initial height of the central platform 1 is recorded as 0mm;

[0057] s6, profile bending, start bending and stretching, and the stretching deformation is controlled between 1.7% and 2.5%;

[0058] s7, stretching and bending to finalize. After s6 stretching and bending is completed, the height of the central platform 1 is raised step by step and the pitch angles of the chucks A12 and B13 are adjusted so that the bottom of the profile fits with the through groove A4 at the top of the arc of the stretching and bending die;

[0059] s8, unloading, chuck A12 and chuck B13 tilt downward 0.1°, unloading the tensile force, opening chuck A12 and chuck B13, and the stretching cylinder retreats until the profile is completely out of chuck A12 and chuck B13, unloading is carried out, and the tensile force unloading time is recorded as m2. The time of the profile bending process is controlled to be m1-m2<3h, where h is hours. The crane is started to transport the bent No. 1 rib profile to the rack and lay it flat. The curvature deviation of the profile outer contour is tested with an arc test plate, and the position of the mold workbench is reset to zero;

[0060] s9, cutting the profile, sawing the profile of s8, cutting and scrapping the bent part formed by the contact between the profile and the chuck A12 and the chuck B13, leaving part of the profile between the central platform 1 and the chuck A12 or the chuck B13, and obtaining the bent profile.

[0061] s6 includes:

[0062] A1, the central platform 1 rises from the initial position 0mm, the initial rising height is 373mm, the lifting speed of the central platform 1 is 6mm / s-8mm / s, until the bottom of the profile contacts the arc top of the bending die, and the straightening force is 180t;

[0063] A2, the central platform 1 continues to rise to 570mm, all the profiles enter the bending die, the bottom of the profile enters the through groove A4, the bottom surface of the reinforcement rib A8 and the bottom surface of the reinforcement rib C10 contact with the bottom surface of the through groove B5, the bottom surface of the reinforcement rib B9 and the bottom surface of the reinforcement rib D11 contact with the bottom surface of the through groove C6, the profile is supported and bent, and the straightening force is 360t.

[0064] s7 includes:

[0065] B1, keep the height of central platform 1 at 570mm, and at the same time, the conjugate pitch of chuck A12 and chuck B13 increases from 0° to 5°. After the pitch is completed, central platform 1 continues to rise to 1034mm, and the straightening force is 439t-445t, so that the profile fits the bending die;

[0066] B2, keep the height of the central platform 1 at 1034mm, and at the same time increase the conjugate pitch of the chuck A12 and the chuck B13 from 5° to 7°. After the pitch is completed, the central platform 1 continues to rise to 1128mm, and the straightening force is 463t-479t;

[0067] B3, keep the height of the central platform 1 at 1128mm, and at the same time increase the conjugate pitch of the chuck A12 and the chuck B13 from 7° to 10°. After the pitch is completed, the central platform 1 continues to rise to 1293mm, and the straightening force is 486t-504t;

[0068] B4, keep the height of the central platform 1 at 1293mm, and at the same time increase the conjugate pitch of the chuck A12 and the chuck B13 from 10° to 13°. After the pitch is completed, the central platform 1 continues to rise to 1427mm, and the straightening force is 516t-532t;

[0069] B5, keep the height of the central platform 1 at 1427mm, and at the same time increase the conjugate pitch of chuck A12 and chuck B13 from 13° to 16°. After the pitch is completed, the central platform 1 continues to rise to 1600mm, and the straightening force is 574t-589t.

[0070] The stretching machine is a 2000T stretching machine, the clamping force of chuck A12 and chuck B13 on the profile is 150t, the angular deviation between adjacent parting molds that make up mold A2 is less than ±0.01°, the angular deviation between adjacent parting molds that make up mold B3 is less than ±0.01°, and the angular deviation between the straight line between the stretching and bending mold and chuck A12 and chuck B13 is less than ±0.02°.

[0071] The stretch-bending die is arranged along the length direction of the central platform 1 and the top surface is an upwardly convex arc surface. The die A2 and the die B3 are combined to form through grooves B5 and through grooves C6. The width of through groove A4 is smaller than that of through groove B5, and the width of through groove B5 is smaller than that of through groove C6. The top end of through groove A4 is connected to the bottom surface of through groove B5, and the top end of through groove B5 is connected to the bottom surface of through groove C6. Through grooves A4, through grooves B5 and through grooves C6 extend along the length direction of the central platform 1.

[0072] The rib profile No. 1 includes a central plate extending along the length direction. On the cross-section of the rib profile No. 1, the central plate includes a main body and an extension portion, the extension portion is arranged at the top and bottom of the main body, four reinforcing ribs are connected to the main body, the reinforcing rib A8 and the reinforcing rib B9 are located on the same side of the main body, the reinforcing rib C10 and the reinforcing rib D11 are located on the other side of the main body, the reinforcing rib A8 and the reinforcing rib C10 correspond in position in the horizontal direction, the reinforcing rib B9 and the reinforcing rib D11 correspond in position in the horizontal direction, the vertical length of the reinforcing rib A8 is shorter than that of the reinforcing rib C10, the vertical length of the reinforcing rib B9 is shorter than that of the reinforcing rib D11, and the reinforcing ribs A8 and C10 are arranged at the bottom of the reinforcing ribs B9 and D11.

[0073] The cross section of mold A2 includes four steps from bottom to top, and the cross section of mold B3 includes three steps from bottom to top.

[0074] The riser surface of the first step of mold A2 fits with the lower riser surface of the first step of mold B3;

[0075] A through groove A4 is formed between the kick surface of the second step of mold A2 and the upper half kick surface of the first step of mold B3;

[0076] A through groove B5 is formed between the riser surface of the third step of the mold A2 and the riser surface of the second step of the mold B3;

[0077] A through groove C6 is formed between the riser surface of the fourth step of mold A2 and the riser surface of the third step of mold B3.

[0078] The through groove A4 clamps the extension of the bottom of the central plate, the through groove B5 clamps the reinforcing rib A8 and the reinforcing rib C10, and the through groove C6 clamps the reinforcing rib B9 and the reinforcing rib D11;

[0079] The tread of the first step of mold A2 abuts against the end of the extension of the bottom of the central plate, and the riser of the second step of mold A2 and the riser of the first step of mold B3 clamp the extension of the bottom of the central plate from both sides;

[0080] The tread of the second step of mold A2 abuts against the bottom of the reinforcing rib A8, the riser of the third step of mold A2 abuts against the end of the reinforcing rib A8, the tread of the first step of mold B3 abuts against the bottom of the reinforcing rib C10, and the riser of the second step of mold B3 abuts against the end of the reinforcing rib C10;

[0081] The tread of the third step of mold A2 abuts against the bottom of the reinforcing rib B9, the riser of the fourth step of mold A2 abuts against the end of the reinforcing rib B9, the tread of the second step of mold B3 abuts against the bottom of the reinforcing rib D11, and the riser of the third step of mold B3 abuts against the end of the reinforcing rib D11.

[0082] When the chuck A12 and the chuck B13 clamp the No. 1 rib profile, six inserts with anti-slip grooves are arranged around the No. 1 rib profile. The six inserts fill the gaps of the No. 1 rib profile and form a rectangle together with the No. 1 rib profile in the cross section.

[0083] The cross-sectional view of the profile of the present invention is as follows Figure 1 As shown, it includes horizontal plate 7, reinforcing rib A8, reinforcing rib B9, reinforcing rib C10, and reinforcing rib D11. The schematic diagram of the No. 1 rib profile structure is as shown in Figure 2As shown, X is the horizontal projection length of the arc formed by the horizontal plate 7 of the product bending part, which is 5120mm, and Y is the vertical projection length of the arc formed by the horizontal plate 7 of the product bending part, which is 460mm. The cross-sectional view of the profile when used in conjunction with the bending die is as follows: Figure 3 As shown, it includes mold A2, mold B3, through groove A4, through groove B5, through groove C6, horizontal plate 7, reinforcing rib A8, reinforcing rib B9, reinforcing rib C10, and reinforcing rib D11. The structural diagram of the No. 1 rib profile and the bending mold is shown in Figure 4 As shown, it includes a central platform 1, a mold B3, a horizontal plate 7, a chuck A12, and a chuck B13. The insert and the profile are used in combination as shown in the figure Figure 5 As shown, it includes insert A14, insert B15, insert C16, insert D17, insert E18, and insert F19. The left side bending test arc sample of the No. 1 rib profile is as follows Figure 6 As shown in the figure, the arc test sample of the right side bending profile of rib profile No. 1 is as follows Figure 7 As shown, including inner arc 20 and outer arc 21, the produced No. 1 rib bending profile is tested using the left detection arc template and the right detection arc template, and the curvature deviation of the outer contour is checked, X1 is the lateral projection length of the left detection arc template 2269.27mm, Y1 is the longitudinal projection length of the left detection arc template 197.61mm, X2 is the lateral projection length of the right detection arc template 2263.68mm, Y2 is the longitudinal projection length of the right detection arc template 197.55mm, the detection arc template is divided into inner arc 20 and outer arc 21, the inner arc 20 is compared with the inner diameter of the No. 1 rib profile, and the outer arc 21 is compared with the outer diameter of the No. 1 rib profile, and the maximum curvature deviation of the No. 1 rib profile and the outer contour of the left / right detection arc template over the entire length is required to be less than 2.3mm.

[0084] In the present invention, after the mold A2 and the mold B3 are combined, through grooves A4, B5 and C6 are formed. The width of through groove A4 is smaller than that of through groove B5, and usually the width of B is smaller than that of through groove C6; the top of through groove A4 is connected to the bottom of through groove B5, and the top of through groove B5 is connected to the bottom of through groove C6; through grooves A4, B5 and C6 extend along the length direction of the central platform 1; the profile includes a horizontal plate 7, and the two sides of the horizontal plate 7 with the largest areas are side A and side B respectively; reinforcing ribs A8 and B9 are provided on side A, and reinforcing rib B9 is located above reinforcing rib A8, and reinforcing rib C10 and D11 are provided on side B, and reinforcing rib D11 is located above reinforcing rib C10; the horizontal center lines of reinforcing ribs A8 and C10 are located on the same horizontal plane, and reinforcing ribs B 9 and the horizontal center lines of the reinforcing ribs D11 are located on the same horizontal plane; the lengths of the reinforcing ribs A8, B9, C10 and D11 are the same as the length of the horizontal plate 7; when in use, the chucks A12 and B13 of the stretching machine are respectively located on both sides of the central platform 1 and connected to the two ends of the profile, so that the profile spans above the stretching and bending die; as the stretching machine works, the bottom of the profile enters the through groove A4, the bottom surface of the reinforcing rib A8 and the bottom surface of the reinforcing rib C10 contact the bottom surface of the through groove B5, and the bottom surface of the reinforcing rib B9 and the bottom surface of the reinforcing rib D11 contact the bottom surface of the through groove C6; during the stretching process, the horizontal plate 7, the reinforcing ribs A8, B9, C10 and D11 of the profile can all be effectively supported, and can improve the deformation accuracy of the profile during the stretching process, thereby improving the yield rate.

[0085] The reinforcing rib B9 contacts the inner side surface of the chuck A12, and an insert A14 is provided in the gap between the reinforcing rib A8 and the chuck A12, an insert B15 is provided in the gap between the insert A14, the reinforcing rib A8 and the reinforcing rib B9, and an insert C16 is provided in the gap between the reinforcing rib B9 and the chuck A12; an insert D17 is provided in the gap between the reinforcing rib C10 and the chuck A12, an insert E18 is provided in the gap between the reinforcing rib C10, the chuck A12 and the reinforcing rib D11, and an insert F19 is provided in the gap between the reinforcing rib D11 and the chuck A12; this arrangement makes the chuck A12 and the chuck B13 clamp the profile more firmly. The insert blocks A14, B15, C16, D17, E18 and F19 are all provided with anti-skid patterns for clamping the profiles to prevent the profiles from slipping out of the chuck A12 or B13 due to slipping during the bending process.

[0086] In the experimental process of the present invention, at s6, the profile is bent: bending and stretching are started, and the stretching deformation is controlled between 1.7% and 2.5%; at s7, during the bending and shaping, the height of the central platform 1 is maintained at 570mm, and the conjugate pitch of the chuck A12 and the chuck B13 is increased from 0° to 5°. After the pitch is completed, the central platform 1 continues to rise to 1034mm, and the straightening force is 439t-445t, so that the profile is further fitted with the bending die; 4 groups of experiments are provided in the present invention as shown in Table 1.

[0087] Table 1 Maximum curvature deviation of the contour

[0088]

[0089] It can be seen from the above table that the bent profiles obtained by the bending methods of Experiment 1 and Experiment 3 of the present invention meet the standards. Comparison of Experiment 1 and Experiment 2 shows that the profile needs to continue to be bent and shaped after being bent, and the bending angles of chuck A12 and chuck B13 during bending and shaping are much larger than the bending angles required by the specification. Comparison of Experiment 3 and Experiment 4 shows that the bending time of the profile must be controlled within 3 hours after heat treatment, otherwise the maximum curvature deviation of the profile's outer contour is likely to exceed the specified range. On the basis of using the mold of the present invention and using the bending method of the present invention, the maximum curvature deviation of the outer contour is controlled within 2.3 mm.

[0090] It can be seen that the present invention uses a large-tonnage special stretching machine, utilizes the rotation and tilting functions of the stretching chuck, cooperates with the designed special mold, and optimizes the parameters of the stretching process to achieve multi-stage stretching and bending of the No. 1 rib upper edge strip profile of the civil wing. The No. 1 rib used in the present invention is mainly used for connecting the wing to the wing long stringer, with small deviation of the outer contour and high qualified rate.

[0091] Preferably, when the bent profile is placed horizontally, X is the transverse projection length of the arc formed by the horizontal plate 7 of the bent portion of the product, which is 5120 mm, and Y is the longitudinal projection length of the arc formed by the horizontal plate 7 of the bent portion of the product, which is 460 mm.

[0092] Preferably, the produced No. 1 rib bending profile is inspected using a left-side detection arc template and a right-side detection arc template to check the curvature deviation of the outer contour, X1 is the lateral projection length of the left-side detection arc template 2269.27mm, Y1 is the longitudinal projection length of the left-side detection arc template 197.61mm, X2 is the lateral projection length of the right-side detection arc template 2263.68mm, Y2 is the longitudinal projection length of the right-side detection arc template 197.55mm, the detection arc template is divided into an inner arc 20 and an outer arc 21, the inner arc 20 is compared with the inner diameter of the No. 1 rib profile, and the outer arc 21 is compared with the outer diameter of the No. 1 rib profile, and the maximum curvature deviation of the No. 1 rib profile and the outer contour of the left / right detection arc templates over the entire length is required to be less than 2.3mm.

[0093] In the present invention, the basic principle of the stretching and bending forming is that the stretching and bending die is fixed to the central platform 1, and the stretching machine stretches the profile to rotate around the stretching and bending die, so that the profile raw material undergoes plastic deformation under the action of tension and bending moment, and gradually fits the stretching and bending die, thereby obtaining a part of the desired shape. The aluminum profile stretching and bending process can enable the parts to obtain a reasonable shape correction margin, improve the manufacturing accuracy of the parts, and reduce the manufacturing cost of the parts. Direct stretching and bending of aluminum profiles can replace the welding of multiple sections of aluminum profiles to reduce costs.

[0094] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features may be replaced by equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-angle bending method for a No. 1 rib profile of a civil wing, wherein a bending device is used for bending, wherein the bending device comprises a stretching machine and a bending mechanism, wherein the stretching machine and a bending die are used in combination, wherein the bending die is located on a central platform (1) of the stretching machine, wherein the bending die comprises a combined die A (2) and a combined die B (3), wherein the die A (2) and the die B (3) form a through groove A (4), wherein a chuck A (12) and a chuck B (13) having the same structure are used to clamp the No. 1 rib profile from both ends thereof, wherein the method comprises: The stretch bending process includes: s1, preparation work, after solution quenching treatment of the extruded profile, stretch and bend it, record the quenching completion time m1, and install the stretch and bending device; s2, the stretch-bending device is positioned, the distance between the chuck A (12) and the chuck B (13) is adjusted to 12000 mm, the central platform (1) is located between the chuck A (12) and the chuck B (13), and the distance between the chuck A (12) and the chuck B (13) and the central platform (1) is 6000 mm; s3, the profile is fixed by using soft slings of equal length and a crane to lift the profile steadily so that the profile is located above the central platform (1). The clamps A (12) and B (13) of the stretching machine clamp and fix the two ends of the profile; s4, straightening the profile. After the two ends of the profile are clamped and fixed, the chuck A (12) and the chuck B (13) are rotated to a horizontal position, and a tensile force is applied to the chuck A (12) and the chuck B (13); s5, mold positioning, adjust the lifting device, so that the height of the central platform (1) rises to the point where the arc top of the bending mold contacts the bottom of the profile, and the bottom of the profile enters the through groove A (4) of the bending mold, and the initial height of the central platform (1) is recorded as 0 mm; s6, profile bending, starting bending and stretching, the stretching deformation is controlled between 1.7% and 2.5%; s7, stretching and bending to finalize the shape. After the stretching and bending is completed in s6, the height of the central platform (1) is raised step by step and the pitch angles of the chuck A (12) and the chuck B (13) are adjusted so that the bottom of the profile fits with the through groove A (4) at the top of the arc of the stretching and bending die; s8, unloading, chuck A (12) and chuck B (13) tilt downward 0.1°, unloading the tensile force, opening chuck A (12) and chuck B (13), and retracting the tensile cylinder until the profile is completely out of chuck A (12) and chuck B (13), unloading, recording the tensile force unloading time as m2, controlling the profile bending process time m1-m2<3h, h is hours, starting the crane to transport the bent No. 1 rib profile to the rack and lay it flat, using the detection arc template to check the curvature deviation of the profile outer contour, and returning the mold workbench position to zero; s9, cutting the profile, sawing the profile of s8, cutting and scrapping the bent portion formed by the contact between the profile and the chuck A (12) and the chuck B (13), leaving the portion of the profile between the central platform (1) and the chuck A (12) or the chuck B (13), and obtaining the bent profile.

2. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 1, characterized in that s6 include: A1, the central platform (1) rises from the initial position 0mm, the initial rising height is 373mm, the lifting speed of the central platform (1) is 6mm / s-8mm / s, until the bottom of the profile contacts the arc top of the bending die, and the straightening force is 180t; A2, the central platform (1) continues to rise to 570mm, the profiles all enter the bending die, the bottom of the profiles enter the through groove A (4), the bottom surface of the reinforcing rib A (8) and the bottom surface of the reinforcing rib C (10) contact the bottom surface of the through groove B (5), the bottom surface of the reinforcing rib B (9) and the bottom surface of the reinforcing rib D (11) contact the bottom surface of the through groove C (6), and the profiles are supported and bent, and the straightening force is 360t.

3. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 2, characterized in that: s7 includes: B1, keep the height of the central platform (1) at 570mm, and at the same time increase the conjugate pitch of chuck A (12) and chuck B (13) from 0° to 5°. After the pitch is completed, the central platform (1) continues to rise to 1034mm, and the straightening force is 439t-445t, so that the profile fits the bending die; B2, keep the height of the central platform (1) at 1034mm, and at the same time increase the conjugate pitch of chuck A (12) and chuck B (13) from 5° to 7°. After the pitch is completed, the central platform (1) continues to rise to 1128mm, and the straightening force is 463t-479t; B3, keep the height of the central platform (1) at 1128mm, and at the same time increase the conjugate pitch of chuck A (12) and chuck B (13) from 7° to 10°. After the pitch is completed, the central platform (1) continues to rise to 1293mm, and the straightening force is 486t-504t; B4, keep the height of the central platform (1) at 1293mm, and at the same time increase the conjugate pitch of chuck A (12) and chuck B (13) from 10° to 13°. After the pitch is completed, the central platform (1) continues to rise to 1427mm, and the straightening force is 516t-532t; B5, keep the height of the central platform (1) at 1427mm, and at the same time increase the conjugate pitch of chuck A (12) and chuck B (13) from 13° to 16°. After the pitch is completed, the central platform (1) continues to rise to 1600mm, and the straightening force is 574t-589t.

4. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 3, characterized in that: The stretching machine is a 2000T stretching machine. The clamping force of the chuck A (12) and the chuck B (13) on the profile is 150t. The angle deviation between adjacent partings constituting the mold A (2) is less than ±0.01°, the angle deviation between adjacent partings constituting the mold B (3) is less than ±0.01°, and the angle deviation between the straight line between the stretching and bending mold and the chuck A (12) and the chuck B (13) is less than ±0.02°.

5. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 4, characterized in that: The bending die is arranged along the length direction of the central platform (1) and the top surface is an arc surface convex upwards. The die A (2) and the die B (3) are combined to form a through groove B (5) and a through groove C (6). The width of the through groove A (4) is smaller than the width of the through groove B (5), and the width of the through groove B (5) is smaller than the width of the through groove C (6). The top of the through groove A (4) is connected to the bottom surface of the through groove B (5), and the top of the through groove B (5) is connected to the bottom surface of the through groove C (6). The through groove A (4), the through groove B (5) and the through groove C (6) extend along the length direction of the central platform (1).

6. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 5, characterized in that: The rib profile No. 1 includes a central plate extending along the length direction. On the cross section of the rib profile No. 1, the central plate includes a main body and an extension portion, the extension portion is arranged at the top and the bottom of the main body, four reinforcing ribs are connected to the main body, the reinforcing rib A (8) and the reinforcing rib B (9) are located on the same side of the main body, the reinforcing rib C (10) and the reinforcing rib D (11) are located on the other side of the main body, the reinforcing rib A (8) and the reinforcing rib C (10) are located in the horizontal direction. The reinforcing rib B (9) and the reinforcing rib D (11) are located in the horizontal direction. The vertical length of the reinforcing rib A (8) is shorter than that of the reinforcing rib C (10), and the vertical length of the reinforcing rib B (9) is shorter than that of the reinforcing rib D (11). The reinforcing ribs A (8) and the reinforcing rib C (10) are arranged at the bottom of the reinforcing ribs B (9) and the reinforcing rib D (11).

7. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 6, characterized in that: The cross section of mold A (2) includes four steps from bottom to top, and the cross section of mold B (3) includes three steps from bottom to top.

8. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 7, characterized in that: The riser surface of the first step of mold A (2) and the lower riser surface of the first step of mold B (3) fit together; A through groove A (4) is formed between the riser surface of the second step of the mold A (2) and the upper half riser surface of the first step of the mold B (3); A through groove B (5) is formed between the riser surface of the third step of the mold A (2) and the riser surface of the second step of the mold B (3); A through groove C (6) is formed between the riser surface of the fourth step of mold A (2) and the riser surface of the third step of mold B (3).

9. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 8, characterized in that: The through groove A (4) clamps the extension of the bottom of the central plate, the through groove B (5) clamps the reinforcing rib A (8) and the reinforcing rib C (10), and the through groove C (6) clamps the reinforcing rib B (9) and the reinforcing rib D (11); The tread of the first step of mold A (2) abuts against the end of the extension of the bottom of the central plate, and the riser of the second step of mold A (2) and the riser of the first step of mold B (3) clamp the extension of the bottom of the central plate from both sides; The tread of the second step of the mold A (2) abuts against the bottom of the reinforcing rib A (8), the riser of the third step of the mold A (2) abuts against the end of the reinforcing rib A (8), the tread of the first step of the mold B (3) abuts against the bottom of the reinforcing rib C (10), and the riser of the second step of the mold B (3) abuts against the end of the reinforcing rib C (10); The tread of the third step of mold A (2) abuts against the bottom of the reinforcing rib B (9), the riser of the fourth step of mold A (2) abuts against the end of the reinforcing rib B (9), the tread of the second step of mold B (3) abuts against the bottom of the reinforcing rib D (11), and the riser of the third step of mold B (3) abuts against the end of the reinforcing rib D (11).

10. A multi-angle bending method for a No. 1 rib profile of a civil wing as claimed in claim 9, characterized in that: When the clamp A (12) and the clamp B (13) clamp the No. 1 rib profile, six inserts with anti-slip grooves are arranged around the No. 1 rib profile. The six inserts fill the gaps of the No. 1 rib profile and form a rectangle together with the No. 1 rib profile in the cross section.

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