A method for integrally manufacturing a composite engine lip part

Abstract

The application discloses a kind of composite integrated manufacturing method of engine lip parts, it is related to aero-engine parts forming technology.Deep drawing process and electromagnetic induction auxiliary heating progressive roll forming process are integrated on the same set of mould to complete, and after forming, rubber bag is shaped to improve the precision of parts.The manufacturing method is realized based on integrated mould, the integrated mould includes lip piece punch, shaping cover plate, blank holder, assembly die, inner gasket ring, outer gasket ring and concave die;Manufacture is carried out according to the following steps: step 1, deep drawing forming;Step 2, laser cutting;Step 3, electromagnetic induction auxiliary heating progressive roll forming forming;Step 4, trimming;Step 5, rubber bag shaping.Integrated mould makes that workpiece does not need repeated clamping and handling between deep drawing and progressive forming, the design of assembly die makes a set of mould can complete two-step deep drawing-progressive forming lip processing and rubber bag shaping integration.

Description

Technical Field

[0001] This invention relates to aero-engine component forming technology, specifically to an integrated method for sheet metal deep drawing-electromagnetic induction progressive roll forming composite forming of engine inlet lip parts, and for shape correction. Background Technology

[0002] Engine lip components are ring-shaped or irregularly shaped critical structural parts located at the front end of an aero-engine or air intake. Their core function is to smoothly guide and rectify the airflow entering the engine, while also withstanding aerodynamic loads, foreign object impacts, vibrations, and potential temperature fluctuations from the anti-icing system. The aerodynamic shape accuracy of this component directly determines the total pressure recovery coefficient and the degree of flow field distortion in the air intake, thus significantly affecting the engine's thrust, fuel economy, and surge margin. Typical engine lip components have complex geometric features such as high curvature thin walls and annular hollow structures. Their outer surface is usually a three-dimensional freeform surface conforming to a specific airfoil curve, while the inner surface mates with the support structure or anti-icing channel.

[0003] To meet the requirements of high thrust-to-weight ratio and harsh service environments, engine lip components are generally made of lightweight but difficult-to-deform materials such as high-performance aluminum alloys and titanium alloys. These materials have poor plasticity at room temperature, significant springback, and are extremely sensitive to forming speed and temperature history.

[0004] Currently, traditional manufacturing processes for engine lip parts mainly include: segmented deep drawing followed by welding, segmented-welding cold forming, double-pass deep drawing, and creep aging forming. However, these methods reveal the following shortcomings when addressing the increasingly stringent structural and performance requirements of modern high-performance lip parts:

[0005] Engine lip components are located at the front end of the air intake. Their cross-section often features a ring structure with inner and outer double flanges, placing stringent requirements on aerodynamic shape, dimensional accuracy, and surface quality. Lip components are often the subject of high R&D costs and timelines for small-batch, multi-variety products. Separate welding processes involve numerous steps and significant deformation; casting microstructures and properties are difficult to meet lightweight requirements. Furthermore, deep drawing, when using deep drawing processes for both inner and outer rings simultaneously, is prone to wrinkling due to the lack of a blank holder on the inner side or insufficient space, affecting part quality. If formed in two stages, two sets of molds need to be designed, increasing costs. While electromagnetic induction progressive roll forming, which has emerged in recent years, can achieve inner and outer flange characteristics, its efficiency is low when used alone. Creep aging forming offers high forming accuracy and effective springback control, but its forming cycle is long and its production efficiency is lower than that of electromagnetic induction progressive roll forming.

[0006] Therefore, those skilled in the art urgently need a forming scheme that can balance efficiency and precision, and accurately and efficiently manufacture engine lip parts that can meet the aerodynamic shape accuracy requirements. Summary of the Invention

[0007] To address the above problems, this invention proposes a composite integrated manufacturing method for engine lip parts, which integrates deep drawing process and electromagnetic induction assisted heating progressive roll forming process on the same mold, and performs rubber bladder correction after forming to improve the part's precision.

[0008] The technical solution of the present invention is as follows: the manufacturing method is based on an integrated mold, which includes a lip punch, a shaping cover plate, a pressing die, a combination mold, an inner pad ring, an outer pad ring, and a concave mold;

[0009] The die, lip die, blank holder die, and combination die are installed in the press for deep drawing;

[0010] The lip punch is installed in a rolling forming equipment for local heating and progressive rolling of thin-walled components for flanging.

[0011] Install the die cavity, the combination die, the shaping cover plate, the inner gasket ring, and the outer gasket ring in the press, and insert a rubber bladder for rubber bladder shaping;

[0012] To manufacture, follow these steps:

[0013] Step 1, Deep drawing: Cover the die with a flat plate and press it with a blank holder. Fix the die on the press table with the help of the grooves around the die. Combine the die and the lip punch and install them on the upper die. Then, under the condition of applying a preset temperature, drive the press so that the upper die drives the combined die and the lip punch to move down and draw the plate downward to form a basin-shaped part with an outward flange including the lip part.

[0014] Step 2, Laser Cutting: Using a laser cutting machine, a circular area is cut off in the center of the bottom of the basin-shaped part, thereby forming a central hole at the bottom, and the undeformed part of the plate material is cut off to make the part into a perforated basin-shaped part.

[0015] Step 3, Electromagnetic induction assisted heating progressive rolling and flanging forming: The cavity of the lip part punch faces upward, and its center hole is connected to the lower worktable of the thin-walled component local heating progressive rolling forming equipment to fix the lip part punch.

[0016] The perforated basin-shaped part is inverted and placed on the lip part punch, so that the outer flange of the perforated basin-shaped part that belongs to the lip part fits against the outer wall of the lip part punch.

[0017] The perforated basin-shaped part is formed by using a local heating progressive rolling head to form an inner flange. The area of ​​the perforated basin-shaped part near the central hole is gradually pressed into the cavity of the lip part punch to form the inner flange of the lip part.

[0018] Step 4, trimming: Use laser cutting to cut off the excess part of the outer ring of the lip-shaped part and the excess part of the inner side after the inner flange, and use sandpaper to polish the cut part of the lip to obtain the finished lip-shaped part;

[0019] Step 5, Rubber Bag Shaping: Using the grooves around the die, fix the die on the press table; place the combination die in the center of the die and combine it; then place the finished lip-shaped part in the die, so that the inner flange of the lip part abuts against the outer wall of the combination die, and the outer flange of the lip part abuts against the inner wall of the die. At this time, the combination die and the die together form the standard lip part outline.

[0020] Prepare an annular rubber bladder and place it on the finished lip-shaped part. Then, place the inner shim ring, outer shim ring, and shaping cover plate on top in sequence. The inner and outer shim rings are connected to the shaping cover plate using locating pins. The locating pins are interference-fitted with the inner and outer shim rings and clearance-fitted with the shaping cover plate to allow the shaping cover plate to move axially under the pressure of the press. The function of the inner and outer shim rings is to seal the rubber bladder by connecting it to the shaping cover plate. The press presses the shaping cover plate downward until it is in contact with the edge of the die. The rubber bladder is filled with oil and pressure is maintained through the pipes opened in the shaping cover plate. After the pressure is maintained, the oil in the bladder is sucked out, and the shaped lip-shaped part is taken out.

[0021] Furthermore, the shaped cover plate, the pressing die, and the die have threaded holes around their perimeter for mounting lifting lugs. The lip die has holes punched in the center for fixing to the upper die of the press or the worktable of the rolling equipment for local heating and progressive rolling of thin-walled components. The die has grooves around its perimeter for clamping onto the worktable of the press, thereby fixing the die.

[0022] Furthermore, the outer wall of the lip punch is adapted to the outer flange in the lip part, and it also has a cavity adapted to the inner flange in the lip part.

[0023] Furthermore, the combined mold is used to fill the cavity portion of the lip punch, thereby filling the lip punch and forming a continuous inner wall of the basin-shaped part.

[0024] Furthermore, the calibrating cover plate is provided with a ring-shaped rubber bladder filling space, and the calibrating cover plate is also provided with an oil inlet channel connecting the rubber bladder filling space.

[0025] This invention takes into account the localized thermal deformation characteristics of the electromagnetic induction-assisted heating progressive roll forming process. It utilizes this process to achieve an inner flange feature, effectively avoiding wrinkling issues during the deep drawing of the inner lip ring. The modular mold design allows it to be combined with the lip part punch for the first deep drawing step, or with the die for post-forming rubber bladder shaping. This eliminates the need for three sets of molds required for the original two-step forming and shaping process, creating a single, integrated mold. Combined with the electromagnetic induction-assisted heating progressive roll forming process, it achieves precise forming of the inner lip ring.

[0026] The beneficial effects of this invention are as follows: the combined mold can be freely combined with the lip part punch and die to achieve multiple uses in one mold, forming three types of molds required for stretching basin-shaped parts, electromagnetic induction progressive roll forming inner rings, and shaping parts; deep drawing quickly pre-forms basin-shaped parts, providing the main material distribution and shape basis; then, the electromagnetic induction assisted heating progressive roll forming process is used to turn the inner edge, resulting in a small heat-affected zone and the formation of a clear inner lip, effectively avoiding wrinkling when the inner lip is not pressed enough; the integrated mold eliminates the need for repeated clamping and handling of the workpiece between deep drawing and progressive forming, and the design of the combined mold allows one set of molds to complete the two-step deep drawing-progressive forming lip processing and rubber bladder shaping in one integrated manner. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the first step of deep drawing, showing the lip part punch and the combination die.

[0028] Figure 2 This is a schematic diagram of the second step of progressive forming.

[0029] Figure 3 This is a schematic diagram of the forming process, showing the combination of the concave mold and the composite mold.

[0030] Figure 4 This is a schematic diagram of a formed lip part.

[0031] Figure 5 This is a schematic diagram of all the molds.

[0032] Figure 6 This is a cross-sectional view of the oil inlet passage. Detailed Implementation

[0033] To clearly illustrate the technical features of the present invention, the present invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings.

[0034] This embodiment focuses on the deep drawing-incremental forming process for manufacturing a 2219 aluminum alloy lip part for a certain type of aero-engine. The initial sheet material used is a 2219 aluminum alloy plate with a thickness of 2mm and a side length of 2200mm. Specific examples are provided below for illustration:

[0035] like Figure 1 As shown, in this case, the integrated mold includes a lip punch, a shaping cover plate, a pressing die, a combination mold, an inner pad ring, an outer pad ring, and a die.

[0036] The sizing cover plate, pressing die, and die cavity have threaded holes around them for mounting lifting lugs. The lip punch has holes for fixing to the upper part of the press or the lower part of the progressive forming machine. The combination die has holes for combining with the lip punch / die.

[0037] The lip-shaped punch and the combined die have a cavity that matches the outer contour of the basin-shaped part.

[0038] The lip punch is aligned with the inner wall of the target basin-shaped part and can be used as a punch for progressive roll forming.

[0039] like Figure 3 As shown, the die has grooves around its perimeter for clamping in the lower slide of the press to fix the die.

[0040] The die and the combination die have a cavity that matches the outer contour of the actual part for shaping.

[0041] Process according to the following steps:

[0042] Step 1, Deep drawing: Cover the flat plate with the die and press it with the blank holder. Combine the die and the lip punch and install them on the upper part of the press. Then, under the condition of applying the preset temperature, drive the press so that the upper die drives the combined lip punch downward to draw the plate at a speed of 100mm / min to form a basin-shaped part with an outward flange, thus forming the outward flange feature of the engine lip part. The hot deep drawing is completed to obtain a basin-shaped part with a closed bottom and complete side walls.

[0043] Step 2, Laser Cutting: Use a laser cutting machine to cut out a circular area in the center of the bottom of the basin-shaped part (the radius of the circular area should not be too large, and sufficient allowance should be left for the inner ring of the lip), thereby forming a central hole with a radius of 350mm at the bottom, and cutting off the undeformed part of the plate material to make the part into a perforated basin-shaped part.

[0044] Step 3: Progressive Rolling and Flanging Forming with Electromagnetic Induction Assisted Heating: Disassemble the lip punch and the combined mold. Install bolts in the center hole of the lip punch and connect it to the worktable of a progressive rolling forming equipment for thin-walled components (such as the one shown in Chinese Invention Application No. CN 120532934 A) to fix the mold. The lip punch is consistent with the inner wall of the target basin-shaped part and can be used as the punch for progressive rolling forming. Place the perforated basin-shaped part on the lip feature protrusion of the upper mold. Use the electromagnetic induction rolling head to progressively roll the top of the perforated basin-shaped part inwards in circles to form the inner flange of the lip part with electromagnetic induction assisted heating. The tool head moves according to the preset forming trajectory in the first layer to complete the forming of the first layer planar contour. Then the tool head feeds a certain step amount to enter the processing of the next layer contour. Repeat this forming process to finally complete the inner flange feature, causing part of the material to bend inward to form the inner flange, and finally obtain a lip-shaped part prototype with flange features on both the inside and outside.

[0045] Step 4, Trimming: Use laser cutting to remove the excess outer edge and inner edge of the lip-shaped part. Then, use 400#, 800#, 1200#, and 2000# sandpaper to polish the cut areas of the lip, obtaining the finished lip-shaped part.

[0046] Step 5, Rubber Bag Shaping: The die cavity is positioned under the press by pressing the grooves around its perimeter with a pressure plate, and the combined mold is placed inside the die cavity and assembled with it. The finished part is then placed in the die cavity, and the inner shim ring, outer shim ring, rubber bag, and shaping cover plate are placed on top in sequence. A locating pin passes through the inner shim ring, outer shim ring, rubber bag, and shaping cover plate to seal the rubber bag. The inner and outer shim rings provide a good seal and provide space for the rubber bag during the initial assembly. Initially, the rubber bag is annular and 10mm thick. At this point, the combined mold and die cavity form the outer wall of the standard lip part. The press presses downwards, pressing the shaping cover plate and applying oil through the oil inlet channel of the shaping cover plate (e.g., ...). Figure 6 As shown, the rubber bladder is filled with oil and maintained at 190°C and 30MPa for 2 hours to achieve the desired shape correction for the engine lip. Afterward, the oil is allowed to cool naturally before being drained from the bladder, and the corrected lip part is removed.

[0047] The integrated mold and method provided by this invention can also be used for high-temperature deep drawing, forming, and shaping of similar lip parts made of materials such as titanium alloys and stainless steel, requiring only adjustments to the temperature and mold shape. By combining deep drawing with electromagnetic induction rolling progressive forming and rubber bladder shaping, a multi-purpose composite forming method is proposed, achieving low-cost, high-precision, and high-efficiency manufacturing of engine lips.

[0048] There are many specific ways to implement this invention. The above description is only a preferred embodiment of this invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of this invention, and these improvements should also be considered within the scope of protection of this invention.

Claims

1. A composite integrated manufacturing method for engine lip parts, characterized in that, This manufacturing method is based on an integrated mold, which includes a lip punch, a shaping cover plate, a pressing die, a combination mold, an inner shim ring, an outer shim ring, and a die. The die, lip die, blank holder die, and combination die are installed in the press for deep drawing; The lip punch is installed in a rolling forming equipment for local heating and progressive rolling of thin-walled components for flanging. Install the die cavity, the combination die, the shaping cover plate, the inner gasket ring, and the outer gasket ring in the press, and insert a rubber bladder for rubber bladder shaping; To manufacture, follow these steps: Step 1, Deep drawing: Cover the die with a flat plate and press it with a blank holder. Fix the die on the press table with the help of the grooves around the die. Combine the die and the lip punch and install them on the upper die. Then, under the condition of applying a preset temperature, drive the press so that the upper die drives the combined die and the lip punch to move down and draw the plate downward to form a basin-shaped part with an outward flange including the lip part. Step 2, Laser Cutting: Using a laser cutting machine, a circular area is cut off in the center of the bottom of the basin-shaped part, thereby forming a central hole at the bottom, and the undeformed part of the plate material is cut off to make the part into a perforated basin-shaped part. Step 3, Electromagnetic induction assisted heating progressive rolling and flanging forming: With the cavity of the lip part punch facing upward, the four central holes of the punch are connected to the lower worktable of the thin-walled component local heating progressive rolling forming equipment to fix the lip part punch. The perforated basin-shaped part is inverted and placed on the lip part punch, so that the outer flange of the perforated basin-shaped part that belongs to the lip part fits against the outer wall of the lip part punch. The perforated basin-shaped part is formed by using a local heating progressive rolling head to form an inner flange. The area of ​​the perforated basin-shaped part near the central hole is gradually pressed into the cavity of the lip part punch to form the inner flange of the lip part. Step 4, trimming: Use laser cutting to cut off the excess part of the outer ring of the lip-shaped part and the excess part of the inner side after the inner flange, and use sandpaper to polish the cut part of the lip to obtain the finished lip-shaped part; Step 5, Rubber Bag Shaping: Using the grooves around the die, fix the die on the press table; place the combination die in the center of the die and combine it; then place the finished lip-shaped part in the die, so that the inner flange of the lip part abuts against the outer wall of the combination die, and the outer flange of the lip part abuts against the inner wall of the die. At this time, the combination die and the die together form the standard lip part outline. Prepare an annular rubber bladder and place it on the finished lip-shaped part. Then, place the inner shim, outer shim, and shaping cover plate on top in sequence. The inner and outer shims are connected to the shaping cover plate using locating pins. The locating pins are interference-fitted with the inner and outer shims and clearance-fitted with the shaping cover plate to allow the shaping cover plate to move axially under the pressure of the press. The function of the inner and outer shims is to seal the rubber bladder by connecting with the shaping cover plate. The press presses the shaping cover plate downwards to achieve the sealing effect of the inner and outer shims on the rubber bladder. The rubber bladder is filled with oil and pressurized through the oil inlet channel on the side of the shaping cover plate. After pressurization, the oil in the bladder is sucked out, and the shaped lip-shaped part is removed.

2. The composite integrated manufacturing method for an engine lip part according to claim 1, characterized in that, The shaped cover plate, the pressing die, and the die have threaded holes around their perimeter for mounting lifting lugs. The lip punch has four holes for fixing to the upper die of the press or the worktable of the rolling equipment for local heating and progressive rolling of thin-walled components. The die has grooves around its perimeter for clamping onto the worktable of the press, thereby fixing the die.

3. The composite integrated manufacturing method for an engine lip part according to claim 1, characterized in that, The outer wall of the lip punch is adapted to the outer flange in the lip part, and it also has a cavity adapted to the inner flange in the lip part.

4. The composite integrated manufacturing method for an engine lip part according to claim 1, characterized in that, The combined mold is used to fill the cavity portion of the lip punch, thereby filling the lip punch and forming a continuous inner wall of the basin-shaped part.

5. The composite integrated manufacturing method for an engine lip part according to claim 1, characterized in that, The calibrating cover plate is provided with a ring-shaped rubber bladder filling space, and the calibrating cover plate is also provided with an oil inlet channel that connects to the rubber bladder filling space.

Images