A processing method of an aluminum alloy high-bead wall plate part

Abstract

The application provides a processing method of an aluminum alloy high-bead-wall plate part, and belongs to the technical field of aviation sheet metal part manufacturing. The method comprises two parts of roll bending forming and shot forming, and is realized based on a special tool. The special tool is a mold tire with a positioning and pressing function. The tire body profile is arranged according to the profile of the wall plate. The positioning assembly is matched with the positioning hole on the wall plate to realize positioning. The pressing assembly presses the two sides of the wall plate to the surface of the tire body. The wall plate filled with padding is subjected to roll bending forming. The distance between the roller shafts is adjusted to obtain different curvatures, and the special tool is used for inspection. The wall plate is positioned and installed on the special tool to complete shot forming. The special tool prevents secondary positioning during the transition between the roll bending forming and the shot forming processes. The manufacturing precision of the wall plate profile and the distance between the two adjacent beads are ensured through accurate positioning. The gap between the high-bead-wall plate and the tool when finally delivered is not greater than 0.8mm.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of manufacturing of aviation sheet metal parts, and relates to a processing method of an aluminum alloy high-stripe wall plate part. BACKGROUND

[0002] The high-stripe integral wall plate is an aerodynamic shape part of an airplane, has multiple parallel stripes in the length direction, has the characteristics of large curvature, and is used as a load-bearing part of the integral structure of the airplane, has high performance, smooth surface, high strength-to-weight ratio, good air tightness, and the like. The high-stripe integral wall plate can reduce the weight of the airplane, improve the overall stiffness, strength and reliability of the airplane, and the manufacturing technology level of the high-stripe integral wall plate has become one of important indicators for measuring the level of aviation technology.

[0003] The forming of the aluminum alloy integral wall plate is currently mainly based on die pressing and roll bending forming. In the forming process, due to the large residual stress, uneven distribution, different stripe heights, limited width between the stripe grooves, springback of the aluminum alloy material and the like of the integral wall plate, repeated continuous forming is required, which is prone to instability of the stripes and the web, and in severe cases, the stripes and the web can be cracked, resulting in low shape manufacturing precision and seriously affecting the fatigue life of the part.

[0004] With the continuous improvement of the maneuvering performance of the airplane, there is a higher demand for the shape precision and service life of the aluminum alloy high-stripe integral wall plate component, and the traditional process method cannot meet the performance demand, so there is an urgent need for new processing methods to iterate, optimize and improve the manufacturing technology of the aluminum alloy inner and outer high-stripe integral wall plate. SUMMARY

[0005] The application aims to solve the problems of low length direction shape surface precision, poor continuity and unstable quality after traditional forming. In view of the problem of stretch deformation of the high-stripe large-curvature integral wall plate in shot peening forming, the application provides a processing method of an aluminum alloy high-stripe wall plate part, and realizes the precise manufacturing of the aluminum alloy high-stripe wall plate part with unequal distance, unequal height, large curvature and inner and outer stripe characteristics. The processing method can also be used for manufacturing complex aluminum alloy wall plate aviation parts of different thicknesses, different materials and different stripe heights.

[0006] In order to achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows:

[0007] A processing method of an aluminum alloy high rib strip wall plate part, the processing method comprising two parts of roll bending forming and shot peening forming, the roll bending forming is that the high rib strip wall plate filled with padding passes between three synchronously rotating roller shafts to continuously generate plastic bending forming, the mutual distance between the roller shafts is adjusted to obtain different curvatures; the shot peening forming is a special aircraft sheet metal processing method using high-speed spherical projectiles to spray the surface layer to generate plastic deformation. The above combined method is realized based on a special tooling, the special tooling is a mold tire with positioning and pressing functions, which is used for roll bending forming and shot peening forming of the high rib strip wall plate, the positioning and pressing functions of the mold tire are used to prevent secondary positioning during the transfer between the roll bending forming and the shot peening forming processes, to ensure the manufacturing precision of the high rib strip wall plate shape and the distance between the two adjacent rib strips from accurate positioning, and finally the gap between the high rib strip wall plate and the tooling is not greater than 0.8mm when delivered. The specific steps are as follows:

[0008] First step: check the surface quality of the high rib strip wall plate to be formed, including checking whether the high rib strip wall plate to be formed and the product record content are complete, checking the surface state of the material, and the material surface is not allowed to have visible cracks, cracks, scratches, delamination, non-metallic inclusions, bubbles, corrosion spots and other surface defects.

[0009] Second step: check the state of the numerical control skin roll bending machine; check whether all handles of the numerical control skin roll bending machine are normal, whether there is excess material between the roller shafts; adjust the gap between the upper and lower roller shafts according to the thickness of the material of the high rib strip wall plate to be formed; when checking and adjusting the pressure, it should be performed on the screw of the limiting mechanism at the cross beam lever.

[0010] Third step: fill the padding between the rib strips. First, measure the distance between the adjacent rib strips, the length and maximum height of each rib strip of the high rib strip wall plate to be formed, and record the measurement data; second, cut or mill the padding according to the corresponding data; finally, lay the padding between the adjacent rib strips; the total thickness of the padding is equal to the maximum thickness of the rib strip + 0.5mm, and the purpose of filling the padding is to prevent the rib strip from being crushed or broken during the roll bending forming process.

[0011] Fourth step: roll bending forming. The roll bending forming is a pre-forming, and the main forming part is the highest bending part of the wall plate in the transverse direction, which is perpendicular to the rib strip direction. The high rib strip wall plate filled with padding is placed in the numerical control skin roll bending machine, so that the high rib strip wall plate passes between three synchronously rotating roller shafts to continuously generate plastic bending. The rib strip and the roller shaft always keep parallel during the forming process. According to the bending radius of the inner surface of the high rib strip wall plate part before springback, the fixed position of the two lower roller shafts is kept, the three roller shafts are kept parallel, the lowering value of the upper roller shaft is changed with the change of the curvature, the roll bending forming is completed, and the semi-finished wall plate is obtained. The lowering value of the upper roller shaft is calculated as follows:

[0012]

[0013] H - R

[0014] R q R

[0015] R z R

[0016] t

[0017] a

[0018] Fifth step: check the semi-finished wallboard state. Check the semi-finished wallboard surface quality, using special tooling to detect curvature deformation.

[0019] The special tooling is a set of tire body 1 with positioning and pressing function, including positioning assembly 2, pressing assembly 5 and hanging bar 9.

[0020] The upper surface of the tire body 1 is provided according to the profile of the high rib wallboard, and a plurality of blind holes are provided on the two side edges of the upper surface in parallel with the rib of the wallboard. The position and number of the blind holes correspond to the positioning holes on the high rib wallboard, and the blind holes are coaxial with the positioning holes on the high rib wallboard. A plurality of round holes are also provided on the two side edges of the upper surface of the tire body 1 in parallel with the rib of the wallboard.

[0021] The positioning assembly 2 is composed of positioning pins 3 and fixed bushings 4, and the number of the positioning assembly 2 is the same as the number of the positioning holes on the wallboard. The fixed bushings 4 are pressed into the blind holes on the two side edges of the tire body 1, and the positioning pins 3 are inserted into the fixed bushings 4. The two are used together to fix the high rib wallboard.

[0022] The pressing assembly 5 includes a pressing plate 6, an internal hexagonal screw 7 and a steel wire sleeve 8, and the number of the pressing assembly 5 is the same as the number of the round holes on the two side edges of the tire body 1. The pressing plate 6 is a groove structure, and the width of the groove is the same as the outer diameter of the internal hexagonal screw 7. The tail of the internal hexagonal screw 7 is wrapped with the steel wire sleeve 8. The pressing plate 6 is pressed on the two side edges of the high rib wallboard. The internal hexagonal screw 7 wrapped with the steel wire sleeve 8 is inserted into the round holes on the two side edges of the tire body 1 through the pressing plate 6, and is used to press the two side edges of the high rib wallboard to keep the edge position unchanged. The steel wire sleeve 8 is used to improve the connection condition and improve the reliability of the internal hexagonal screw 7 connection, avoid the phenomenon of wire slipping and tooth missing, and improve the service life of the thread.

[0023] The hanging bars 9 are evenly distributed and fixedly installed on the two end faces of the tire body 1 along the rib parallel direction, and are used for lifting the special tooling.

[0024] Place the semi-finished wall panel on the special tooling fixture 1 and check the fit between the highest lateral bending point of the semi-finished wall panel and the top surface of the special tooling fixture 1 to confirm whether the curvature of the semi-finished wall panel meets the requirements. If it does not meet the requirements, return to step four to adjust the parameters and continue rolling and bending.

[0025] Step 6: Inspect the shot peening equipment, take a shot sample and inspect it, screen the shot shape, sieve the shot size, and check the shot cleanliness.

[0026] Step 7: Clean the surface of the semi-finished wall panel.

[0027] Step 8: Select the shot peening area. Based on the curvature and initial deformation characteristics of the semi-finished panel, select the shot peening area and use a strip shot peening method to determine the shot peening path.

[0028] Step 9: Protect the non-formed areas of the semi-finished panel. To prevent deformation of the non-formed areas of the semi-finished panel due to shot blasting, in conjunction with Step 8, the pre-analyzed non-shot blasting paths and areas are protected on the surface of the semi-finished panel using tape.

[0029] Step 10: Install the semi-finished wall panel on the special tooling. Position the semi-finished wall panel on the special tooling through the positioning component 2, and fix the position of the semi-finished wall panel through the clamping component 5. Select and set the parameters of nozzle size, shot peening angle, machine tool feed speed, air pressure, shot flow rate, shot diameter, and shot peening distance to perform shot peening and form a high-rib wall panel.

[0030] Step 11: Shot Peening Correction. Based on the actual needs after shot peening, determine whether shot peening correction is necessary. If the local bending of the high-rib panel exceeds requirements after shot peening, the high-rib panel needs to be removed from the special tooling before reverse shot peening correction. The process parameters and shot peening trajectory for shot peening correction are selected according to actual needs, but generally the correction air pressure should be lower than the shot peening air pressure in that area. The process parameter values ​​for shot peening correction should be as small as possible compared to the process parameter values ​​for shot peening formation, as large process parameter values ​​can cause bulging in thinner parts. To avoid the shot peening area being too large during correction, local protection with tape may be necessary.

[0031] Further, the material of the tire body 1 in the special tool is epoxy resin SAM910, and the surface material is epoxy resin SAM900. The SAM900 and SAM910 resins are non-metallic materials, and have the characteristics of excellent chemical stability, electrical insulation, corrosion resistance, good adhesion and high mechanical properties. The SAM900 resin material is widely used in aircraft part tooling. The material has strong adhesion, high strength, convenient processing and molding, small shrinkage, high dimensional stability, good heat and chemical resistance, and good mechanical processing performance. The surface strength, wear resistance and impact resistance of the material are very close to those of metal materials, so the SAM900 and SAM910 resins are selected to replace traditional metal and non-metal tooling materials.

[0032] Further, the positioning pin 3, the pressing plate 6 and the steel wire screw sleeve 8 in the special tool are made of steel.

[0033] Further, the fixed bushing 4 in the positioning assembly 2 is a press-in threaded bushing.

[0034] The beneficial effects of the present application are as follows:

[0035] The present application meets the manufacturing requirements of complex aluminum alloy wallboard aviation parts with different thicknesses, different aluminum alloy materials and different rib heights, solves the composite forming method of large-curvature inner and outer ribs of the whole wallboard, and meets the shape and performance requirements of the whole inner and outer high-rib wallboard components. The shape precision of the aluminum alloy high-rib whole wallboard component is optimized, and the manufacturing technology of the aluminum alloy inner and outer high-rib whole wallboard is improved. The parts manufactured according to this processing method meet the inspection requirements that the gap between the parts and the tooling is not greater than 0.8mm under the pressure of 200N. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 It is a schematic diagram of the special tool.

[0037] Figure 2 It is an A-A sectional view of the special tool.

[0038] Figure 3 It is a B-direction partial enlarged view of Figure 2

[0039] Figure 4 It is a C-direction partial enlarged view of Figure 2

[0040] In the figure: 1 tire body; 2 positioning assembly; 3 positioning pin; 4 fixed bushing; 5 pressing assembly; 6 pressing plate; 7 inner hexagonal screw; 8 steel wire screw sleeve; 9 hanging rod. DETAILED DESCRIPTION

[0041] ​​In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be described in detail below with reference to the drawings.

[0042] A processing method of an aluminum alloy high rib strip wall plate part, taking a typical 7050T7451 high rib strip large-curvature wall plate aluminum alloy part as an example, the processing method comprising the following steps:

[0043] First step: checking the surface quality of the to-be-formed high rib strip wall plate. Checking whether the wall plate and product record content are complete, checking the material surface state, and the material surface is not allowed to have visible cracks, cracks, scratches, delamination, non-metallic inclusions, bubbles, corrosion spots and other surface defects.

[0044] Second step: checking the equipment state of the numerical control skin roll bending machine. Checking whether all handles of the operating system are normal, and whether there is excess material between the rollers. Adjust the gap between the upper and lower rollers according to the thickness of the to-be-formed high rib strip wall plate material. When checking and adjusting the pressure, it should be done on the screw of the limiting mechanism at the cross beam lever.

[0045] Third step: filling the filler between the ribs. First, prepare the filler between the two adjacent ribs, the filler material is selected from aluminum alloy material, and the material state is preferably T state. Measure the distance between adjacent ribs, the length and maximum height of each rib of the to-be-formed high rib strip wall plate, and record the measurement data. Second, cut or mill the filler according to the corresponding data. The length of each filler is equal to the length of the rib + 5mm, and the thickness of each filler is not limited. Finally, lay the filler between the adjacent ribs. The filler should fill the gap between the adjacent ribs, and the total thickness of the filler is equal to the maximum thickness of the rib + 0.5mm. The purpose of filling the filler is to prevent the rib from being crushed or broken during the roll bending forming process.

[0046] Fourth step: roll bending forming. The roll bending forming is pre-forming, and the main forming part is the highest bending part of the wall plate in the transverse direction (the transverse direction is perpendicular to the rib direction). Place the to-be-formed high rib strip wall plate with filled filler in the numerical control skin roll bending machine, so that the to-be-formed high rib strip wall plate passes between three synchronously rotating rollers, continuously producing plastic bending. During the forming process, the rib always keeps parallel with the roller. According to the bending radius of the inner surface of the high rib strip wall plate before springback, keep the fixed position of the two lower rollers, ensure that the three rollers are parallel to each other, change the lowering value of the upper roller with the change of curvature, complete the roll bending forming, and obtain a semi-finished wall plate. The lowering value of the upper roller is calculated as follows:

[0047]

[0048] In the formula, H is the lowering value of the upper roller, mm

[0049] R q R is the bending radius of the inner surface of the part before springback, mm, the inner surface refers to the side of the high rib strip wall plate without rib.

[0050] R z —Lower roller shaft radius, mm

[0051] t — Material thickness, mm

[0052] a—Half the horizontal center distance between the two lower roller shafts, mm

[0053] The roll forming equipment used is a CNC skin roll forming machine. The inner surface bending radius R of the part before springback during forming is... q It is 280 mm, and the radius of the lower roller shaft is R. z Given a thickness of 50 mm, a material thickness of t of 2.5 mm, and half the horizontal center distance of the lower roller shaft (a) of 210 mm, the calculated drop value H of the upper roller shaft is 82 mm.

[0054] Step 5: Inspect the condition of the semi-finished wall panels. Check the surface quality of the semi-finished products. The surface of the semi-finished products should be free of oil stains, rust, dents, and scratches. Check the curvature deformation of the semi-finished products. The semi-finished products should be free of bulging, loose edges, etc.

[0055] The special tooling is a mold with positioning and clamping functions. The main components of the mold are: mold body 1, positioning component 2, clamping component 5, and lifting rod 9.

[0056] The upper surface of the tire body 1 is designed with a high-ribbed wall panel profile. Four blind holes are provided on both sides of the upper surface parallel to the ribs of the wall panel. The positions of the blind holes correspond to the positioning holes on the high-ribbed wall panel, and the blind holes are coaxial with the positioning holes on the high-ribbed wall panel. Twelve round holes are also provided on both sides of the upper surface of the tire body 1 parallel to the ribs of the wall panel. The tire body 1 measures 2100 mm × 500 mm × 447 mm. The body material is epoxy resin SAM910, and the surface material is epoxy resin SAM900. SAM900 and SAM910 resins are non-metallic materials, characterized by excellent chemical stability, electrical insulation, corrosion resistance, good adhesion, and high mechanical properties. SAM900 resin material is widely used in aircraft parts tooling. This material has strong adhesion, high strength, easy processing and molding, minimal shrinkage, high dimensional stability, and good heat and chemical resistance. In addition, it has good machinability. Its surface strength, wear resistance and impact resistance are very close to those of metal materials. Therefore, SAM900 and SAM910 resins are chosen to replace traditional metal and non-metal tooling materials.

[0057] The positioning assembly 2 is composed of positioning pins 3 and fixed bushings 4. The positioning pins 3 are selected as 1AM-17, with a length of 25mm. The center of the positioning pins 3 is the same as the hole center of the high rib wall plate positioning hole. The fixed bushings 4 are selected as JB / T8005.1999 press-in threaded bushings, with a length of 12mm. The fixed bushings 4 are pressed into the blind holes at the two side edges of the tire body 1. The positioning pins 3 are inserted into the fixed bushings 4, and the two are used in combination to fix the high rib wall plate part.

[0058] The pressing assembly 5 is composed of 12 pressing plates 6, internal hexagonal screws 7 and steel wire nuts 8. Every six are arranged on the two long sides (parallel to the ribs) of the high rib wall plate, in a symmetrical distribution, to press the two side edges of the high rib wall plate part, so that the edge position remains unchanged. The pressing plates 6 are selected as steel materials with a standard of 1AM-35, in a groove structure. The width of the groove is the same as the outer diameter of the internal hexagonal screws 7. The internal hexagonal screws 7 are selected as GB / T70.1, with the tail wrapped with the steel wire nuts 8. The steel wire nuts 8 are selected as GJB119.1A, with a specification of 12mm×1.75mm×10mm. The pressing plates 6 are pressed on the two side edges of the high rib wall plate. The internal hexagonal screws 7 wrapped with the steel wire nuts 8 are inserted into the round holes at the two side edges of the tire body 1 through the pressing plates 6, to press the two side edges of the high rib wall plate, so that the edge position remains unchanged. Among them, the steel wire nuts 8 are used to improve the connection conditions, improve the reliability of the internal hexagonal screws 7 connection, avoid the phenomenon of wire slipping and tooth missing, and improve the service life of the thread.

[0059] The hanging rods 9 are selected as standards 1AM-27, with a specification of 40mm, and four in number. The hanging rods 9 are fixedly installed on the two short sides (perpendicular to the ribs) of the tire body 1 and are uniformly distributed, to hoist the tire body 1.

[0060] The semi-finished wall plate is placed on the special tool tire body 1. The adhesion of the transverse highest bending part of the semi-finished wall plate to the top profile of the special tool tire body 1 is checked, to confirm whether the curvature of the semi-finished wall plate meets the requirements. If not, return to the fourth step to adjust the parameters and continue to roll and bend.

[0061] The sixth step is to check the shot forming equipment. The equipment is checked to be in good condition, and the stable voltage power supply is connected. The accumulated water in the pressure storage tank and the filter is discharged, and the gas source is connected. The air dryer is turned on, and the air cleanliness is checked using a mirror to ensure that the air is dry and clean. The CNC system is started, and the performance of the machine tool is checked through the CNC system self-checking function. It is confirmed whether the current projectile type is consistent with the requirements of the process specification. If not, the projectile is replaced. The machine tool is run for 5 to 10 minutes to check the operation of the machine tool and the circulation of the projectile. It is visually checked whether there is a crack in the nozzle, and the wear of the inner wall of the nozzle is checked using a gage. The diameter wear of the nozzle in use should not exceed 5% of the nominal inner diameter size of the nozzle.

[0062] Step 7: Sampling ASH280 shot sample. Shot sample is selected from the nozzle inside the machine, the specific operation method is as follows: first, empty the shot sampling barrel and place it on the workbench inside the machine; then move the nozzle above the barrel opening, align the nozzle with the sampling barrel and maintain a height of at least 100 mm; finally, run the machine to spray the shot into the barrel, turn off the machine, take out the sampling barrel, and select the shot for inspection.

[0063] Step 8: Screening shot shape. Spread the selected shot of the corresponding model over a 0.25 (ASH280) square inch plane, and arrange the shots neatly without overlapping. Visually inspect and use a minimum 10x magnifying lens inspection method according to ASH280 to screen out unqualified shots and deformed shots. Shot inspection period is controlled at 40h of cumulative work of shot peening or when new shots are added.

[0064] Step 9: Screening shot size. Select a standard test screen according to the shot model, randomly sample 100 grams of shot in the shot barrel, screen on a rotary shaker, screen for 5 minutes ± 5 seconds, and check whether the screen oversize meets the requirements. If the shot size screening is unqualified, the automatic shot blasting machine should increase the shot circulation times until the screening is qualified. Shot size and breakage rate inspection is conducted by the operator and the inspector together. Shot inspection period is controlled at 40h of cumulative work of shot peening or when new shots are added.

[0065] Step 10: Checking shot cleanliness. The shot should be dry, rust-free, oil-free, and free of contaminants such as metal chips. The inspection method is to use a gas pressure of 0.1 Mpa to spray a flat and clean aluminum plate (the material, state, and thickness of the aluminum plate are not limited) at a distance of 100-120 mm for 1 minute. After spraying, cover the aluminum plate with a layer of water film and check whether the water film is broken. If it is broken, it means that the shot has oil stains. The inspection is conducted by the operator and the inspector together.

[0066] Step 11: Cleaning the surface of the semi-finished wall panel. Use the required cleaning agent to manually clean the surface of the part.

[0067] Step 12: Selecting shot peening forming area. Select the shot peening forming area according to the curvature structure characteristics and initial deformation state of the semi-finished wall panel, use strip shot peening method, and determine the shot peening forming path.

[0068] Step 13: Protecting non-forming area of semi-finished wall panel. In order to prevent the non-forming area of the semi-finished wall panel from being deformed by shot blasting, use P-68 type adhesive tape to protect the non-shot peening area on the surface of the semi-finished wall panel according to the analysis in Step 12. The protection area tolerance should meet the drawing and process specification. If not specified, the protection area tolerance is 0~+3mm.

[0069] Fourteenth step: install the semi-finished wall plate on the special tool, position the semi-finished wall plate on the special tool through the positioning assembly 2, and fix the position of the semi-finished wall plate through the pressing assembly 5; select and set the nozzle size, shot angle, machine feed speed, air pressure, shot flow, shot diameter, and shot distance parameters, and perform shot forming to obtain a high rib wall plate. Nozzle selection: a single nozzle is usually selected for shot forming; shot angle: when 90° shot can be achieved, the shot angle is selected to be 90°; machine speed: when other process parameters can be adjusted, the maximum machine feed speed is selected; air pressure: select an appropriate air pressure according to the part material, thickness, and different area bending radius; shot flow: usually select a smaller shot flow, generally not more than 8 kg / min; shot diameter size: the shot diameter size represents the limit capacity of shot forming, and ASH280 (0.028 inches) is generally selected; shot distance: the distance mainly affects the strip width, and can be selected according to the size of the shot forming area. The part material in forming is 7050-T7451, the material thickness is 2.5 mm, the maximum height of the rib is 25 mm, and the shot forming process parameters are as follows: 1 nozzle, 90° shot angle, 4000-6000 mm / min machine speed, 0.1-0.3 mpa air pressure, 8 kg / min shot flow, 0.028 inch shot diameter size, and 400 mm shot distance.

[0070] Fifteenth step: shot correction. According to the actual needs after shot forming, it is determined whether to perform shot correction. If the local bending degree of the high rib wall plate after shot forming exceeds the requirement of the drawing, reverse shot correction is needed; the process parameters and shot trajectory of shot correction are selected according to actual needs, but generally the correction air pressure should be lower than the area shot forming air pressure, and the process parameter value of shot correction is preferably smaller than the process parameter value of shot forming, otherwise it will cause the drumming of thin parts. In order to avoid that the shot area is too large during correction, a P-68 type adhesive tape is used for local protection when necessary.

[0071] Position and fix the finally formed high rib wall plate on the special tool, apply 200N pressure to the high rib wall plate, and detect that the fit gap between the high rib wall plate and the special tool is not greater than 0.8 mm, and the high rib wall plate meets the requirements.

[0072] The above-described embodiments only express the implementation of the present application, but cannot be interpreted as a limitation on the scope of the present application. It should be noted that, for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application.

Claims

1. A method of machining an aluminum alloy high stringer wall panel part, characterized by, The processing method comprises the following steps: First step: checking the surface quality of the high-stiffener strip wallboard to be formed; Second step: checking the equipment state of the numerical control skin roll bending machine; Third step: filling the filler between the stiffeners of the high-stiffener strip wallboard to be formed; Fourth step: roll bending forming; placing the high-stiffener strip wallboard to be formed filled with the filler into the numerical control skin roll bending machine, so that the high-stiffener strip wallboard to be formed passes between three synchronously rotating roller shafts, continuously generates plastic bending, and the stiffeners always keep parallel to the roller shafts during the forming process; according to the bending radius of the inner surface of the high-stiffener strip wallboard part before springback, the fixed positions of the two lower roller shafts are kept, the three roller shafts are kept parallel to each other, the lowering value of the upper roller shaft is changed with the change of the curvature, the roll bending forming is completed, and the semi-finished wallboard is obtained; Fifth step: checking the state of the semi-finished wallboard; checking the surface quality of the semi-finished wallboard, and detecting the curvature deformation condition by using a special tool; placing the semi-finished wallboard on the special tool, checking the adhesion degree of the highest bending part of the semi-finished wallboard in the transverse direction to the top profile of the special tool, and confirming whether the curvature of the semi-finished wallboard meets the requirements; if not, returning to the fourth step to adjust the parameters and continuously performing the roll bending forming; Sixth step: checking the shot blasting forming equipment, sampling the shot sample and checking, screening the shape of the shot, screening the particle size of the shot, and checking the cleanliness of the shot; Seventh step: cleaning the surface of the semi-finished wallboard; Eighth step: selecting the shot blasting forming area; selecting the shot blasting forming area according to the curvature structure characteristics and the initial deformation state of the semi-finished wallboard, adopting the strip shot blasting mode, and determining the shot blasting forming path; Ninth step: protecting the non-forming area of the semi-finished wallboard; combining the eighth step, using the adhesive tape to protect the non-shot blasting path and the non-shot blasting area of the semi-finished wallboard on the surface of the semi-finished wallboard according to the pre-analysis; Tenth step: positioning and installing the semi-finished wallboard on the special tool; selecting and setting the nozzle size, shot blasting angle, machine feeding speed, air pressure, shot flow, shot diameter, shot blasting distance parameters, performing shot blasting forming, and obtaining the high-stiffener strip wallboard; Eleventh step: shot blasting correction; if the local bending degree of the high-stiffener strip wallboard after the shot blasting forming exceeds the requirements, the high-stiffener strip wallboard is removed from the special tool, and the reverse shot blasting correction is performed.

2. The method of claim 1, wherein The third step specifically comprises the following steps: first, measuring the distance between adjacent stiffeners, the length and the maximum height of each stiffener of the high-stiffener strip wallboard to be formed, and recording the measurement data; second, cutting or milling the filler according to the corresponding data; and finally, laying the filler between the adjacent stiffeners; the total thickness of the filler is equal to the maximum thickness of the stiffener + 0.5 mm.

3. The method of claim 2, wherein the aluminum alloy high stringer wall panel component is a fuselage component. The filler material is an aluminum alloy material.

4. The method of claim 1, wherein In the fourth step, the lowering value of the upper roller shaft is calculated according to the following formula: ； In the formula, H is the lowering value of the upper roller shaft, mm; R q — the bending radius of the inner surface of the part before springback, the inner surface refers to the side of the high rib wallboard without ribs, mm; R z — Lower roll radius, mm; t is the material thickness, mm; a is half of the horizontal center distance between the two lower roller shafts, mm.

5. The method of claim 1, wherein In the fifth step, the special tool comprises a tire body (1), a positioning assembly (2) and a pressing assembly (5); The upper surface of the tire body (1) is provided according to the profile of the high-stiffener strip wallboard, a plurality of blind holes are arranged on the two side edges of the upper surface in the parallel direction of the stiffeners of the wallboard, the positions and the number of the blind holes correspond to the positioning holes on the high-stiffener strip wallboard, the blind holes are coaxial with the positioning holes on the high-stiffener strip wallboard, and a plurality of round holes are further arranged on the two side edges of the upper surface in the parallel direction of the stiffeners of the wallboard. The positioning assembly (2) is composed of positioning pins (3) and fixing bushings (4), the number of which is the same as the number of positioning holes on the wallboard, wherein the fixing bushings (4) are pressed into the blind holes at the two side edges of the tire body (1), the positioning pins (3) are inserted into the fixing bushings (4), and the two are used in cooperation for fixing the high rib wallboard; The pressing assembly (5) includes a pressing plate (6), an inner hexagonal screw (7) and a steel wire screw sleeve (8), the number of which is the same as the number of the round holes at the two side edges of the tire body (1); the pressing plate (6) is a groove type structure, the width of the groove is the same as the outer diameter of the inner hexagonal screw (7), the tail of the inner hexagonal screw (7) is wound with the steel wire screw sleeve (8), the pressing plate (6) is pressed on the two side edges of the high rib wallboard, the inner hexagonal screw (7) wound with the steel wire screw sleeve (8) is inserted into the round holes at the two side edges of the tire body (1) after passing through the pressing plate (6), and is used for pressing the two side edges of the high rib wallboard, so that the edge position is kept unchanged.

6. The method of claim 5, wherein, The special tool further includes lifting rods (9) which are uniformly distributed and fixedly installed on the end faces of the tire body (1) in the parallel direction of the ribs, and are used for lifting the special tool.

Images