Method for processing long thin stringers

Abstract

This invention discloses a processing method for long, thin edge-mounted wings. It includes the following steps: wire cutting the edge-mounted wing blank, ensuring allowances are reserved on both sides in the length, width, and thickness directions; aging for stress relief; preliminary cold straightening; designing milling fixtures for semi-finish milling to remove allowances; secondary aging for stress relief; secondary cold straightening; finish milling the outer surface and wing surface of the edge-mounted wing blank to the finished dimensions; designing grinding fixtures, clamping the wing surface, and grinding the smaller assembly surface until the thickness of the ground assembly surface is the same as the finished assembly surface thickness. This invention does not employ a hot straightening process, yet it can still guarantee the flatness of long, thin edge-mounted wings, solving the technical problem of large deformation in long, thin edge-mounted wings and avoiding the high cost and low efficiency of hot straightening.

Description

Technical Field

[0001] This invention relates to the field of solid rocket motor manufacturing technology, specifically to a method for processing long, thin leading-edge slats. Background Technology

[0002] Solid rocket engines are the power plants of spacecraft, consisting of main components such as the combustion chamber, propellant grains, nozzle, and igniter. The combustion chamber shell is a key component of the solid rocket engine, providing power to the spacecraft through propellant combustion and enduring high temperatures and pressures during flight. The leading-edge extensions (LES) are external components of the combustion chamber shell, playing a role in controlling and adjusting the spacecraft's flight attitude.

[0003] Solid rocket motors typically have four leading-edge extensions (LEXs), evenly distributed along the engine's flight path on the outer circumference mounting base. Each LEX is simultaneously fixed to multiple mounting bases, requiring high precision in LEX flatness and thickness. Operating in high-temperature and high-pressure environments, LEXs demand high high-temperature strength and thermal stability, generally utilizing high-temperature alloys or titanium alloys. However, machining LEX blanks is difficult, resulting in significant part deformation.

[0004] The traditional processing method for edge strip blanks involves pressing the workpiece with a pressure plate, then milling to ensure uniform thickness in all parts of the part, and finally using a straightening fixture to perform heat straightening one by one to ensure flatness. However, the straightening fixture is bulky and has a low furnace loading capacity, resulting in low production efficiency and high production costs, which is not conducive to mass production. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a processing method for long and thin edge strips that can ensure the flatness of long and thin edge strips without using a thermal straightening process. This solves the technical problem of large deformation of long and thin edge strips and avoids the drawbacks of high cost and low efficiency of thermal straightening.

[0006] To achieve the above objectives, the present invention provides a processing method for a long, thin edge strip, which is characterized by comprising the following steps:

[0007] S1) The edge strip blank is cut by wire cutting to ensure that allowances are reserved on both sides in the length direction, width direction and thickness direction of the blank;

[0008] The wing includes a wing surface and a mounting surface. The outer edge of the mounting surface is provided with T-slots arranged at intervals, and waist holes corresponding to the T-slots are drilled on the mounting surface.

[0009] S2) The cut edge strip blanks are subjected to aging stress relief;

[0010] S3) Perform preliminary cold shaping on the edge strip blank after stress relief by aging;

[0011] S4) Design a milling fixture to semi-finish mill the length, width, and thickness of the edge strip blank after preliminary cold straightening.

[0012] S5) Perform secondary aging stress relief on the semi-finish milled edge flange blank;

[0013] S6) Perform secondary cold straightening on the edge strip blank after secondary aging stress relief;

[0014] S7) The length, width, wing thickness, and two bevels of the side strip blank are precision milled to the finished size using a milling fixture;

[0015] S8) Design a grinding fixture, clamp the edge strip wing surface, and grind the assembly surface so that the thickness of the ground assembly surface is the same as the thickness of the finished assembly surface.

[0016] Furthermore, in S1), a 2-4 mm allowance is reserved on both sides of the length direction of the edge strip blank, a 2-4 mm allowance is reserved on both sides of the width direction, and a 1-2 mm allowance is reserved on both sides of the thickness direction.

[0017] Further, in S4), the milling fixture includes a base, the surface of which is provided with a planar assembly seat, the surface of which is chiseled with a groove that matches the edge wing blank, and the width of the assembly seat surface on one side of the groove along the length direction is smaller than the width of the edge wing blank.

[0018] The groove side is chiseled with spaced first screw holes along the length of the edge wing blank, and the first screw holes are perpendicular to and abut against the long side of the edge wing blank. An accumulator screw is installed in the first screw hole. The inner surface of the groove is provided with spaced second screw holes along the length of the edge wing blank. The upper surface of the mounting base is chiseled with spaced second screw holes on both sides along the length of the edge wing blank. A first mounting screw is installed in each second screw hole.

[0019] The surface of the mounting base is provided with first pressure plates arranged at intervals along the length direction of the edge wing blank, and the first pressure plates extend along the width direction of the mounting base and are connected to the groove by first mounting screws. A gasket is provided between the first pressure plate and the mounting base.

[0020] The groove surface is provided with second pressure plates arranged at intervals along the length direction of the edge wing blank, and the second pressure plates extend along the width direction of the mounting base and are connected to the mounting base by first mounting screws at both ends.

[0021] Furthermore, in S4), a milling fixture is used to clamp the edge flange blank for semi-finish milling in the length and width directions. The specific method is as follows:

[0022] Using the milling fixture as a leveling block, the edge wing blank is placed horizontally on one side surface of the assembly seat, and then the first pressure plate is placed on the upper surface of the edge wing blank. The first pressure plate is fixed by the first assembly screw, thereby pressing the edge wing blank onto the milling fixture. The length direction and width direction of the edge wing blank are milled to the design length and design width dimensions respectively.

[0023] The edge flange blank is clamped using a milling fixture for semi-finish milling in the thickness direction. The specific method is as follows:

[0024] Place the edge wing blank in the groove, screw the nut screw into the first screw hole, and press the edge wing blank along the length direction to the side, so that the edge wing blank is not subjected to a force perpendicular to the thickness direction, and mill both sides of the edge wing blank in the thickness direction to the first design thickness.

[0025] Furthermore, in S7), a milling fixture is used to clamp the edge flange blank for precision milling in both length and width directions. The specific method is as follows:

[0026] Using the milling fixture as a leveling block, the edge wing blank is placed on one side surface of the assembly seat, and then the first pressure plate is placed on the upper surface of the edge wing blank. The first pressure plate is fixed by the first assembly screw, thereby pressing the edge wing blank onto the milling fixture. The length direction and width direction of the edge wing blank are milled to the corresponding finished size.

[0027] The edge flange blank is clamped using a milling fixture and precision milled in the thickness direction. The specific method is as follows:

[0028] Place the edge wing blank in the groove, screw in the grommets in the first screw holes, and tighten the edge wing blank along its length. Without any force perpendicular to the thickness direction, mill both sides of the edge wing blank along its thickness direction to the second design thickness. Then, place the edge wing blank in the groove again, and use the first mounting screws to fix both ends of the second pressure plate to the mounting base. For every 0.2mm of excess material removed, loosen the second pressure plate 2-9, move the edge wing, and press the second pressure plate against the machined area. Mill the area covered by the second pressure plate in the next step. For every 0.6mm of excess material removed, flip the blank over and clamp it, then mill the other side. Finally, mill the wing surface thickness to the finished size.

[0029] The flange blank is clamped using a milling fixture, and the oblique edges on both sides of the flange surface are precision milled. The specific method is as follows:

[0030] Place the edge wing blank on one side of the mounting base and tilt it downwards. Then place the shim on the upper surface of the wing surface and place the first pressure plate on the upper surface of the shim. Fix the first pressure plate with the first mounting screw to press the wing surface onto the milling fixture. Mill one side of the wing surface. After milling one side of the wing surface, rotate the edge wing 180° and mill the other side of the wing surface to the finished wing surface size.

[0031] Furthermore, in S7), when the thickness direction of the edge strip blank is milled to the second design thickness on both sides, it is required that the feed per cut be 0.1mm, and after removing 0.2mm of the allowance, the blank is flipped and clamped to mill the other side. Finally, the overall thickness of the edge strip is milled to the second design thickness, and the flatness is guaranteed to be within 0.12. The second design thickness is 0.2 to 0.4mm greater than the finished product thickness.

[0032] Further, in S8), the grinding fixture includes a lower base plate and an upper base plate; one side edge of the upper base plate and the lower base plate is drilled with a threaded through hole, and a second mounting screw is provided in the threaded through hole; the other side edge of the upper base plate is drilled with a countersunk hole, and a third mounting screw is provided in the countersunk hole; a cavity for clamping the edge strip wing surface is provided between the lower base plate and the upper base plate.

[0033] Furthermore, in S8), the specific method for grinding the edge blade surface using a grinding fixture is as follows:

[0034] S81) Tighten the second mounting screw to connect the lower base plate and the upper base plate together. Then insert the wing surface of the edge strip into the cavity formed by the lower base plate and the upper base plate. Tighten the third mounting screw to press the wing surface of the edge strip onto the lower base plate. When the edge strip is installed on the grinding fixture, the wing surface needs to protrude 8 to 12 mm. When grinding the assembly surface, measure the height difference between the assembly surface and the wing surface.

[0035] S82) Use the electromagnetic chuck on the grinding machine to clamp the grinding fixture equipped with the edge blade, and use a dial indicator to check the runout of the exposed part of the edge blade surface. The runout should not be greater than 0.05. If the requirement is not met, copper sheet should be used to adjust the grinding fixture.

[0036] S83) Grind the mounting surface of the edge strip. When grinding the mounting surface, the height difference between the grinding surface and the airfoil surface is measured by dial gauge to determine the grinding allowance.

[0037] Furthermore, in S83), the grinding surface allowance is C+A / 2-B / 2, where A is the measured thickness of the airfoil, B is the theoretical thickness of the assembly surface, and C is the height difference between the surface to be ground and the airfoil.

[0038] Furthermore, it also includes step S9), which uses a simulated wing mount to detect the matching degree between the strake wing assembly surface and the engine wing mount, and verifies whether the machining accuracy and form and position tolerances of the long and thin strake wing meet the assembly requirements and design requirements.

[0039] The simulated wing seat includes a detection seat, on which are arranged in a straight line at intervals. Each of the detection seats is provided with a slot that matches the T-shaped slot in the vertical state. Through detection holes are provided on both sides of the slot, and the detection holes match the waist holes. Matching fourth assembly screws are provided in the detection holes.

[0040] The advantages of this invention are:

[0041] 1. This invention first performs wire cutting, stress relief, and preliminary leveling on the edge wing blank; then, using a self-designed milling fixture, the edge wing blank is clamped, and the length, width, and thickness of the edge wing blank are semi-finished to remove excess material; next, the edge wing blank is stress-relieved and leveled a second time; then, using a self-designed milling fixture, the edge wing blank is clamped, and the length, width, and two beveled edges of the edge wing blank are milled to the corresponding finished dimensions. The thickness of the edge wing blank is the second design thickness, and the wing surface is directly milled to obtain the finished wing surface thickness dimension; finally, using a self-designed grinding fixture, the assembly surface is ground so that the thickness of the ground assembly surface is the finished assembly surface thickness.

[0042] 2. This invention inspects the finished leading-edge slats by using a self-designed simulated wing mount to simulate the engine wing mount structure, and designs a leading-edge slat inspection gauge to inspect the matching degree between the leading-edge slat assembly surface and the engine wing mount, and to verify whether the machining accuracy and geometric tolerances of the long and thin leading-edge slats meet the assembly requirements and design requirements.

[0043] The processing method for long and thin edge strips of the present invention can ensure the flatness of long and thin edge strips without using a hot straightening process, thus solving the technical problem of large deformation of long and thin edge strips and avoiding the defects of high cost and low efficiency of hot straightening. Attached Figure Description

[0044] Figure 1 This is a three-dimensional structural diagram of the finished edge-strip wing of the present invention;

[0045] Figure 2 This is a three-dimensional structural diagram of the milling fixture in this invention;

[0046] Figure 3 for Figure 2 A three-dimensional structural diagram of a milling fixture for semi-finish milling in the length and width directions, using a clamping edge wing.

[0047] Figure 4 for Figure 2 A three-dimensional structural diagram of a milling fixture for semi-finish milling in the thickness direction, using a clamping edge blade.

[0048] Figure 5 for Figure 2 A three-dimensional structural diagram of a milling fixture for precision milling of edge strips in length and width directions, as well as T-slots and waist-shaped holes;

[0049] Figure 6 for Figure 2 A three-dimensional structural diagram of a milling fixture used for precision milling of the oblique edges on both sides of the wing surface;

[0050] Figure 7 for Figure 2 A three-dimensional structural diagram of the milling fixture used for precision milling of the edge strip in the thickness direction;

[0051] Figure 8 This is a three-dimensional structural diagram of the grinding fixture in this invention;

[0052] Figure 9 for Figure 8 A three-dimensional structural diagram of the grinding fixture used for grinding the assembly surface by clamping the edge blades;

[0053] Figure 10 This is a three-dimensional structural diagram of the simulated wing seat in this invention;

[0054] Figure 11 for Figure 10 A three-dimensional structural diagram of a simulated wing mount assembly with a leading-edge slat wing for testing.

[0055] In the diagram: 1. Edge slat wing; 2. Milling fixture; 3. Grinding fixture; 4. Simulated wing mount.

[0056] The wing 1 includes: wing surface 1-1, mounting surface 1-2, T-slot 1-3, and waist hole 1-4;

[0057] The milling fixture 2 includes: base 2-1, assembly seat 2-2, groove 2-3, first screw hole 2-4 (not shown in the figure), grommet screw 2-5, second screw hole 2-6, first assembly screw 2-7, first pressure plate 2-8, second pressure plate 2-9, and washer 2-10.

[0058] The grinding fixture 3 includes: a lower base plate 3-1, an upper base plate 3-2, a threaded through hole 3-3, a countersunk hole 3-4, a cavity 3-5, a second assembly screw 3-6, and a third assembly screw 3-7;

[0059] The simulated wing mount 4 includes: a detection seat 4-1, a mounting base 4-2, a mounting slot 4-3, a detection hole 4-4, and a fourth assembly screw 4-5. Detailed Implementation

[0060] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0062] In this embodiment, a long, thin leading-edge slat wing for a solid rocket motor is constructed from GH1131 solution-strengthened iron-based high-temperature alloy hot-rolled sheet. The wing has a length of 1300 mm, a width of 140 mm, a surface thickness of 4.0 ± 0.15 mm, a mounting surface thickness of 6.0 (-0.03 / -0.045) mm, a surface flatness of 0.15, and a surface symmetry relative to the mounting surface of 0.06. The processing method for this long, thin leading-edge slat wing includes the following steps:

[0063] S1) The blank of the edge wing 1 is cut by wire cutting to ensure that the blank has a reserved allowance on both sides in the length direction, width direction and thickness direction respectively.

[0064] Specifically, a 2-4mm allowance is reserved on both sides of the blank in the length direction, a 2-4mm allowance is reserved on both sides in the width direction, and a 1-2mm allowance is reserved on both sides in the thickness direction. At the same time, in order to reduce the internal stress introduced by traditional plasma cutting and sawing, wire cutting is used for blanking.

[0065] The wing 1 includes a wing surface 1-1 and a mounting surface 1-2. The outer edge of the mounting surface 1-2 is provided with T-slots 1-3 arranged at intervals. Waist holes 1-4 corresponding to the T-slots 1-3 are drilled on the mounting surface 1-2.

[0066] S2) The cut edge strip wing 1 blank is subjected to aging stress relief to eliminate residual stress during the plate cutting and rolling process.

[0067] Specifically, the aging temperature is 750–850℃, and the holding time is 1.8–2.2 hours.

[0068] S3) Perform preliminary cold straightening on the edge strip 1 billet after aging stress relief.

[0069] In this embodiment, a hydraulic press is used to cold-shape the blank of the edge wing 1, requiring a flatness of no more than 1mm, and ensuring that the thickness of the blank can be processed on both sides with a 1mm allowance on each side.

[0070] S4) Design milling fixture 2, and use milling fixture 2 to semi-finish mill the outer surface of the edge strip wing 1 blank after preliminary cold straightening to remove the excess material.

[0071] Specifically, the milling fixture 2 includes a base 2-1, and the surface of the base 2-1 is provided with a planar assembly seat 2-2. The surface of the assembly seat 2-2 is chiseled with a groove 2-3 that matches the blank of the edge wing 1, and the width of the surface of the assembly seat 2-2 on one side of the groove 2-3 along the length direction is smaller than the width of the blank of the edge wing 1.

[0072] The groove 2-3 has first screw holes 2-4 arranged at intervals along the length of the edge wing 1 blank, and the first screw holes 2-4 are perpendicular to and abut against the long side of the edge wing 1 blank. An organic screw 2-5 is installed in the first screw hole 2-4. The inner surface of the groove 2-3 has second screw holes 2-6 arranged at intervals along the length of the edge wing 1 blank. The upper surface of the mounting base 2-2 has second screw holes 2-6 arranged at intervals on both sides along the length of the edge wing 1 blank. A first mounting screw 2-7 is installed in the second screw hole 2-6.

[0073] The surface of the assembly base 2-2 is provided with first pressure plates 2-8 arranged at intervals along the length direction of the blank of the edge strip 1, and the first pressure plates 2-8 extend along the width direction of the assembly base 2-2 and are connected to the groove 2-3 by first assembly screws 2-7. A gasket 2-10 is provided between the first pressure plate 2-8 and the assembly base 2-2.

[0074] The surface of the groove 2-3 is provided with second pressure plates 2-9 arranged at intervals along the length direction of the blank of the edge strip 1, and the second pressure plates 2-9 extend along the width direction of the mounting base 2-2 and are connected to the mounting base 2-2 by first mounting screws 2-7 at both ends.

[0075] Preferably, the first assembly screws 2-7 are M16 screws.

[0076] The edge wing 1 blank is clamped by milling fixture 2 and semi-finished in length and width directions. The specific method is as follows: the milling fixture 2 is used as a leveling block. The edge wing 1 blank is placed horizontally on one side surface of the assembly seat 2-2. Then the first pressure plate 2-8 is placed on the upper surface of the edge wing 1 blank. The first pressure plate 2-8 is fixed by the first assembly screw 2-7, thereby pressing the edge wing 1 blank on the milling fixture 2. The length direction and width direction of the edge wing blank are milled to the design length and design width dimensions respectively.

[0077] Specifically, such as Figure 3 As shown, side surface 1 and side surface 2 are milled to a polished finish. Then, the blank of edge strip 1 is rotated 180° and side surface 3 and side surface 4 are milled, ensuring that the length of the blank is 1.5-2.5 mm longer than the finished product length and the width is 1.5-2.5 mm wider than the finished product width. In this embodiment, the blank length is 1302 mm and the blank width is 142 mm.

[0078] The edge wing 1 blank is clamped by milling fixture 2 for semi-finish milling in the thickness direction. The specific method is as follows: place the edge wing 1 blank in the groove 2-3, screw in the grommet 2-5 in the first screw hole 2-4, and tighten the side of the edge wing 1 blank in the length direction. Under the condition that the edge wing 1 blank is not subjected to a force perpendicular to the thickness direction, the two sides of the edge wing blank in the thickness direction are milled to the first design thickness, and the excess is removed. This avoids the disadvantage of forcibly flattening the edge wing 1 blank, which would make its flatness impossible to correct.

[0079] Specifically, such as Figure 4 As shown, each cut feeds 0.15mm, and after removing 0.3mm of excess material, the blank is flipped and clamped for milling the other side. By continuously flipping and clamping, the deformation of the edge wing 1 blank is constantly corrected, gradually reducing its flatness. The first design thickness is 0.5 to 3.0mm greater than the finished product thickness. In this embodiment, the blank thickness is guaranteed to be 7mm.

[0080] Preferably, in order to control the milling quality, the end mill is an impact-resistant, heat-fatigue-resistant end mill with a sharp cutting edge, a large chip groove, and a large helix angle.

[0081] S5) Perform secondary aging stress relief on the semi-finished edge flange 1 blank to remove the above-mentioned milling stress.

[0082] Preferably, the secondary aging temperature is 750–850℃, and the holding time is 1.8–2.2 hours.

[0083] S6) Perform secondary cold straightening on the edge strip 1 billet after secondary aging stress relief.

[0084] In this embodiment, a hydraulic press is used to perform secondary cold shaping on the blank of the edge wing 1, requiring the flatness to be no more than 0.5mm, and ensuring that the thickness of the blank can be processed on both sides with a 0.5mm allowance on each side.

[0085] S7) The length, width, two oblique sides, and thickness of the wing surface 1-1 blank are precision milled to the finished size using milling fixture 2.

[0086] The edge wing 1 blank is clamped by milling fixture 2 and precision milled in length and width directions. The specific method is as follows: the milling fixture 2 is used as a leveling block. The edge wing 1 blank is placed on one side surface of the assembly seat 2-2. Then the first pressure plate 2-8 is placed on the upper surface of the edge wing 1 blank. The first pressure plate 2-8 is fixed by the first assembly screw 2-7, thereby pressing the edge wing 1 blank on the milling fixture 2. The length direction and width direction of the edge wing blank are milled to the corresponding finished size.

[0087] Specifically, such as Figure 5As shown, side surface 1 and side surface 2 are milled to a polished finish; then the edge strip wing 1 blank is rotated 180° and side surface 3 and side surface 4 are milled. In this embodiment, the blank length is guaranteed to be 1300mm and the width to be 140mm. Finally, T-slots 1-3 and waist-shaped holes 1-4 are milled.

[0088] The edge wing 1 blank is clamped by milling fixture 2 and precision milled in the thickness direction. The specific method is as follows: place the edge wing 1 blank in the groove 2-3, screw in the grommet 2-5 in the first screw hole 2-4, and tighten the side of the edge wing 1 blank in the length direction. Under the condition that the edge wing 1 blank is not subjected to a force perpendicular to the thickness direction, mill both sides of the edge wing blank in the thickness direction to the second design thickness.

[0089] Specifically, each cut feeds 0.1mm, and after removing 0.2mm of excess material, the blank is flipped and clamped for milling the other side. By continuously flipping and clamping, the deformation of the edge wing 1 blank is constantly corrected, gradually reducing its flatness. The second design thickness is 0.5 to 2.8mm greater than the finished product thickness. In this embodiment, when the thickness direction of the edge wing blank is milled to the second design thickness on both sides, the overall thickness of the edge wing is finally milled to 6.6mm, ensuring a flatness within 0.12.

[0090] Provided that the flatness meets the design requirements, then according to Figure 7 As shown, the blank of the edge strip 1 is placed in the groove 2-3. The two ends of the second pressure plate 2-9 are fixed to the mounting base 2-2 using the first mounting screw 2-7. For every 0.2mm of excess material removed, the second pressure plate 2-9 is loosened, and the edge strip 1 is moved so that the second pressure plate 2-9 presses against the machined part. The part covered by the second pressure plate 2-9 is then milled. For every 0.6mm of excess material removed, the blank is flipped and clamped, and the other side is milled. Finally, the bevels on both sides of the wing surface 1-1 are milled to the finished bevel dimensions. In this embodiment, the thickness of the wing surface 1-1 is milled to the finished dimension of 4.0±0.15mm.

[0091] The milling fixture 2 is used to clamp the blank of the edge strip 1 for precision milling of the two oblique edges of the wing surface 1-1. The specific method is as follows: Place the blank of the edge strip 1 on one side surface of the mounting base 2-2, with the mounting surface 1-2 facing downwards at an angle. Then place the shim 2-10 on the upper surface of the wing surface 1-1, and place the first pressure plate 2-8 on the upper surface of the shim 2-10. Fix the first pressure plate 2-8 with the first mounting screw 2-7, thereby pressing the wing surface 1-1 firmly onto the milling fixture 2. Mill one oblique edge of the wing surface 1-1. After milling one oblique edge, rotate the edge strip 180° and mill the other oblique edge to the finished oblique edge size. Figure 6 As shown.

[0092] S8) Design grinding fixture 3, clamp the edge strip wing surface 1-1, and grind the assembly surface 1-2 so that the thickness of the ground assembly surface 1-2 is the thickness of the finished assembly surface.

[0093] The grinding fixture 3 includes a lower base plate 3-1 and an upper base plate 3-2; one edge of the upper base plate 3-2 and the lower base plate 3-1 is chiseled with a threaded through hole 3-3, and a second mounting screw 3-6 is provided in the threaded through hole 3-3; the other edge of the upper base plate 3-2 is chiseled with a countersunk hole 3-4, and a third mounting screw 3-7 is provided in the countersunk hole 3-4; a cavity 3-5 for clamping the edge strip wing surface 1-1 is provided between the lower base plate 3-1 and the upper base plate 3-2.

[0094] Specifically, the grinding fixture 3 is made of 30CrMnSiA steel plate with strong magnetism. The edge wing 1 is clamped by an electromagnetic chuck and the grinding fixture 3, which solves the problem of the weak magnetism of high temperature alloys and the difficulty of clamping them on the grinding machine.

[0095] The grinding process of the side spar assembly surface 1-2 includes:

[0096] S81) Tighten the second assembly screw 3-6 to connect the lower base plate 3-1 and the upper base plate 3-2 together. Then insert the side strip wing surface 1-1 into the cavity 3-5 formed by the lower base plate 3-1 and the upper base plate 3-2. Tighten the third assembly screw 3-7 to press the side strip wing surface 1-1 onto the lower base plate 3-1. When the side strip wing 1 is installed on the grinding fixture 3, the wing surface 1-1 needs to protrude 8-12mm. When grinding the assembly surface 1-2, measure the height difference between the assembly surface 1-2 and the wing surface 1-1.

[0097] S82) Use the electromagnetic chuck on the grinding machine to clamp the grinding fixture 3 equipped with the edge blade 1, and use a dial indicator to check the runout of the exposed part of the edge blade surface 1-1. The runout should not be greater than 0.05. If the runout is not met, copper sheet should be used to adjust the grinding fixture 3.

[0098] S83) Grind the edge strip wing assembly surface 1-2. When grinding the assembly surface 1-2, the height difference between the grinding surface and the wing surface 1-1 is measured by dial gauge to determine the grinding surface allowance.

[0099] Specifically, in S83), the grinding surface allowance is C+A / 2-B / 2, where A is the measured thickness of the airfoil 1-1, B is the theoretical thickness of the assembly surface 1-2, and C is the height difference between the surface to be ground and the airfoil 1-1.

[0100] Preferably, the second assembly screw 3-6 is an M12 screw, and the third assembly screw 3-7 is an M8 aluminum screw.

[0101] In this embodiment, when the edge wing 1 is installed on the grinding fixture 3, the wing surface 1-1 is exposed with a width of 10mm. When grinding the assembly surface 1-2, the height difference between the assembly surface 1-2 and the wing surface 1-1 is measured. The grinding surface allowance is confirmed by measuring the height difference between the two wing surfaces 1-1 relative to the assembly surface 1-2.

[0102] During the grinding process, one side of the assembly surface 1-2 is ground first, leaving a grinding allowance of 0.03mm. Then, the other side of the assembly surface 1-2 is ground to the required dimensions. Finally, it is ground again to the final finished size. When grinding the other side, the tooling and the edge strip must be turned over together to avoid introducing clamping errors. In this embodiment, the tooling is ground again to the final finished size of 6.0mm.

[0103] The processing method of the present invention further includes step S9), using a simulated wing mount 4 to detect the matching degree between the leading edge wing assembly surface 1-2 and the engine wing mount, and to verify whether the processing accuracy and form and position tolerance of the long thin leading edge wing 1 meet the assembly requirements and design requirements.

[0104] The simulated wing seat 4 includes a detection seat 4-1, on which are arranged in a straight line at intervals, each of the detection seats 4-2 having a slot 4-3 that matches the vertical T-slot 1-3, and through detection holes 4-4 on both sides of the slot 4-3, which match the waist hole 1-4, and a matching fourth assembly screw 4-5 is provided in the detection hole 4-4.

[0105] Preferably, the fourth assembly screw 4-5 is an M6 countersunk screw.

[0106] In this embodiment, seven T-slots 1-3 are provided on the assembly surface 1-2, and seven waist holes 1-4 are provided accordingly. Seven card holders 4-2 are provided on the simulated wing seat 4.

[0107] The simulated wing mount 4 is used to simulate the engine wing mount structure. A leading-edge extension wing inspection gauge is designed to perform a qualification inspection on the leading-edge extension wing. If the leading-edge extension wing can be smoothly installed into the gauge slot 4-3 without jamming, and all seven inspection holes 4-4 on the wing mount can be screwed into the fourth assembly screw 4-5 to secure the leading-edge extension wing, then the machining accuracy and dimensional tolerances of the long, thin leading-edge extension wing meet the assembly and design requirements. In this embodiment, all seven inspection holes 4-4 on the gauge mount can be screwed into the fourth assembly screw 4-5 to secure the leading-edge extension wing without interference, indicating that the machining accuracy and dimensional tolerances of the long, thin leading-edge extension wing meet the assembly and design requirements.

[0108] The processing method for long and thin edge strips of the present invention can ensure the flatness of long and thin edge strips without using a hot straightening process, thus solving the technical problem of large deformation of long and thin edge strips and avoiding the defects of high cost and low efficiency of hot straightening.

[0109] The present invention provides a preferred embodiment, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for processing a long, thin edge strip, characterized in that, Includes the following steps: S1) The edge strip (1) blank is cut by wire cutting to ensure that the blank has a reserved allowance on both sides in the length direction, width direction and thickness direction respectively; The wing (1) includes a wing surface (1-1) and a mounting surface (1-2). The outer edge of the mounting surface (1-2) is provided with T-slots (1-3) arranged at intervals. Waist holes (1-4) corresponding to the T-slots (1-3) are drilled on the mounting surface (1-2). S2) The cut-off edge strip (1) blank is subjected to aging stress relief; S3) Perform preliminary cold straightening on the edge strip flange (1) billet after aging stress relief; S4) Design milling fixture (2) and use milling fixture (2) to semi-finish mill the length, width and thickness of the edge strip (1) blank after preliminary cold straightening to remove excess material; The milling fixture (2) includes a base (2-1), and a mounting seat (2-2) arranged in a plane is provided on the surface of the base (2-1). The mounting seat (2-2) has a groove (2-3) that matches the blank of the edge wing (1) and the width of the mounting seat (2-2) on one side of the groove (2-3) along the length direction is smaller than the width of the blank of the edge wing (1). The groove (2-3) has first screw holes arranged at intervals along the length of the blank of the side strip (1), and the first screw holes are perpendicular to and abut against the long side of the blank of the side strip (1). Organic screws (2-5) are installed in the first screw holes. The inner surface of the groove (2-3) has second screw holes (2-6) arranged at intervals along the length of the blank of the side strip (1). The upper surface of the mounting base (2-2) has second screw holes (2-6) arranged at intervals on both sides along the length of the blank of the side strip (1). A first mounting screw (2-7) is installed in each second screw hole (2-6). The surface of the mounting base (2-2) is provided with first pressure plates (2-8) arranged at intervals along the length direction of the blank of the side strip (1), and the first pressure plates (2-8) extend along the width direction of the mounting base (2-2) and are connected to the groove (2-3) by first mounting screws (2-7). A gasket (2-10) is provided between the first pressure plate (2-8) and the mounting base (2-2). The surface of the groove (2-3) is provided with second pressure plates (2-9) arranged at intervals along the length direction of the blank of the side strip (1), and the second pressure plates (2-9) extend along the width direction of the mounting base (2-2) and are connected to the mounting base (2-2) by first mounting screws (2-7) at both ends; The milling fixture (2) is used to clamp the edge wing (1) blank for semi-finish milling in length and width directions. The specific method is as follows: Using the milling fixture (2) as a leveling block, the edge wing (1) blank is placed horizontally on one side surface of the assembly base (2-2), and the first pressure plate (2-8) is placed on the upper surface of the edge wing (1) blank. The first pressure plate (2-8) is fixed by the first assembly screw (2-7), thereby pressing the edge wing (1) blank onto the milling fixture (2). The length direction and width direction of the edge wing (1) blank are milled to the designed length and width dimensions respectively. The edge flange (1) blank is clamped using a milling fixture (2) for semi-finish milling in the thickness direction. The specific method is as follows: Place the edge wing (1) blank in the groove (2-3), screw in the nut screw (2-5) in the first screw hole, press the edge wing (1) blank along the length direction, so that the edge wing (1) blank is not subjected to a force perpendicular to the thickness direction, and mill the two sides of the edge wing (1) blank along the thickness direction to the first design thickness. S5) Perform secondary aging stress relief on the semi-finished edge flange (1) blank; S6) Perform secondary cold straightening on the edge strip flange (1) billet after secondary aging stress relief; S7) The length, width, thickness of the wing surface (1-1), and the two bevels of the side strip wing (1) blank are precision milled to the finished size using milling fixture (2); The milling fixture (2) is used to clamp the edge wing (1) blank for precision milling in the length and width directions. The specific method is as follows: Using the milling fixture (2) as a leveling block, place the edge wing (1) blank on one side surface of the assembly base (2-2), and then place the first pressure plate (2-8) on the upper surface of the edge wing (1) blank. Fix the first pressure plate (2-8) with the first assembly screw (2-7) to press the edge wing (1) blank onto the milling fixture (2). Mill the two sides of the length direction and the two sides of the width direction of the edge wing (1) blank to the corresponding finished size. The edge flange (1) blank is clamped by a milling fixture (2) and precision milled in the thickness direction. The specific method is as follows: Place the edge wing (1) blank in the groove (2-3), screw in the machine screw (2-5) in the first screw hole, and tighten the edge wing (1) blank along the length direction. Under the condition that the edge wing (1) blank is not subjected to a force perpendicular to the thickness direction, mill the two sides of the edge wing (1) blank in the thickness direction to the second design thickness. Then place the edge wing (1) blank in the groove (2-3), and use the first assembly screw (2-7) to fix the two ends of the second pressure plate (2-9) on the assembly base (2-2). It is required that for every 0.2mm of excess material removed, the second pressure plate (2-9) is loosened, the edge wing (1) is moved, and the second pressure plate (2-9) is pressed against the machined part. The part covered by the second pressure plate (2-9) in the upper step is milled. For every 0.6mm of excess material removed, the side is flipped and clamped, and the other side is milled. Finally, the thickness of the wing surface (1-1) is milled to the finished size. The edge flange (1) blank is clamped using a milling fixture (2) and the two sides of the flange surface (1-1) are precision milled in the direction of the inclined sides. The specific method is as follows: Place the blank of the edge wing (1) on one side surface of the assembly base (2-2) and tilt the assembly surface (1-2) downwards. Then place the shim (2-10) on the upper surface of the wing surface (1-1) and place the first pressure plate (2-8) on the upper surface of the shim (2-10). Fix the first pressure plate (2-8) with the first assembly screw (2-7) to press the wing surface (1-1) onto the milling fixture (2). Mill the oblique edge of one side of the wing surface (1-1). After milling one oblique edge, rotate the edge wing (1) 180° and mill the other oblique edge to the finished oblique edge size. S8) Design grinding fixture (3), clamp the edge strip wing surface (1-1), grind the assembly surface (1-2) so that the thickness of the ground assembly surface (1-2) is the thickness of the finished assembly surface.

2. The processing method for the long thin-edged wing according to claim 1, characterized in that: In S1), a 2-4mm allowance is reserved on both sides of the length direction of the edge strip blank, a 2-4mm allowance is reserved on both sides of the width direction, and a 1-2mm allowance is reserved on both sides of the thickness direction.

3. The processing method for the long thin-edged wing according to claim 1, characterized in that, In S7), when the thickness direction of the edge strip blank is milled to the second design thickness on both sides, it is required that the feed per cut be 0.1mm, and after removing 0.2mm of the allowance, the blank is flipped and clamped to mill the other side. Finally, the overall thickness of the edge strip is milled to the second design thickness, and the flatness is guaranteed to be within 0.

12. The second design thickness is 0.2~0.4mm greater than the finished product thickness.

4. The processing method for the long thin-edged wing according to claim 1, characterized in that, In S8), the grinding fixture (3) includes a lower base plate (3-1) and an upper base plate (3-2); a threaded through hole (3-3) is drilled on one side edge of the upper base plate (3-2) and the lower base plate (3-1), and a second mounting screw (3-6) is provided in the threaded through hole (3-3); a countersunk hole (3-4) is drilled on the other side edge of the upper base plate (3-2), and a third mounting screw (3-7) is provided in the countersunk hole (3-4); a cavity (3-5) for clamping the edge strip wing surface (1-1) is provided between the lower base plate (3-1) and the upper base plate (3-2).

5. The processing method for the long thin-edged wing according to claim 4, characterized in that, In S8), the specific method for grinding the edge blade surface (1-1) using the grinding fixture (3) is as follows: S81) Tighten the second assembly screw (3-6) to connect the lower base plate (3-1) and the upper base plate (3-2) together. Then insert the side wing surface (1-1) into the cavity (3-5) formed by the lower base plate (3-1) and the upper base plate (3-2). Tighten the third assembly screw (3-7) to press the side wing surface (1-1) onto the lower base plate (3-1). When the side wing (1) is installed on the grinding fixture (3), the wing surface (1-1) needs to be exposed with a width of 8~12mm. When grinding the assembly surface (1-2), measure the height difference between the assembly surface (1-2) and the wing surface (1-1). S82) Use the electromagnetic chuck on the grinding machine to clamp the grinding fixture (3) equipped with the edge wing (1), and use a dial indicator to check the runout of the exposed part of the edge wing surface (1-1). The runout should not be greater than 0.

05. If the runout is not met, copper sheet should be used to adjust the grinding fixture (3). S83) Grind the edge strip wing assembly surface (1-2). When grinding the assembly surface (1-2), the height difference between the grinding surface and the wing surface (1-1) is measured by dial gauge to determine the grinding surface allowance.

6. The processing method for the long thin-edged wing according to claim 5, characterized in that: In S83), the grinding surface allowance is C+A / 2-B / 2, where A is the measured thickness of the airfoil (1-1), B is the theoretical thickness of the assembly surface (1-2), and C is the height difference between the surface to be ground and the airfoil (1-1).

7. The processing method for the long thin-edge wing according to claim 1, characterized in that: It also includes step S9), using a simulated wing seat (4) to detect the matching degree between the strake wing assembly surface (1-2) and the engine wing seat, and to verify whether the machining accuracy and form and position tolerance of the long thin strake wing meet the assembly requirements and design requirements; The simulated wing seat (4) includes a detection seat (4-1), on which are arranged in a straight line with slots (4-2). Each slot (4-2) is provided with a slot (4-3) that matches the vertical T-slot (1-3). Through detection holes (4-4) are provided on both sides of the slot (4-3), and the detection holes (4-4) match the waist hole (1-4). A matching fourth assembly screw (4-5) is provided in the detection hole (4-4).

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