Efficient processing method for hot bending large-angle parts
By using laser cutting and thermoforming molds to bend titanium alloy bands in two stages, the problems of low forming accuracy and efficiency of titanium alloy bands have been solved, achieving high-efficiency, low-cost, and high-yield processing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA HANGFA GUIZHOU LIYANG AVIATION POWER CO LTD
- Filing Date
- 2026-03-31
- Publication Date
- 2026-06-05
AI Technical Summary
The problem of low forming accuracy, low efficiency and low pass rate when titanium alloy hoop is bent at both ends by 180°.
After laser cutting, a flattened blank with multiple bands is formed. Deburring and remelting are performed, and after spraying protective coating, it is formed in two stages in a thermoforming mold. The first bending is into a U-shape, and the second bending is into the final shape. The process is carried out using a sliding plate, a mounting plate, a pad, and a baffle. Finally, the bands are disassembled and corrected.
It improved processing efficiency by 90%, increased the pass rate, increased raw material utilization by 37%, and ensured that the parts had no dents or scratches and that the processing consistency was good.
Smart Images
Figure CN122142694A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of machining technology, specifically relating to an efficient machining method for hot-bent large-angle parts. Background Technology
[0002] The ferrule on the aircraft engine is made of TC1 material with a thickness of t=1.5mm. Its design requires bending at both ends at a 180° angle. The structure is as follows: Figure 1 As shown, due to the large bending angle of the part, the titanium alloy experiences excessive springback after cold forming, making it difficult to guarantee bending accuracy. Therefore, hot forming is required to bend the part, but existing hot forming methods have low processing efficiency and low part yield. Summary of the Invention
[0003] This invention aims to provide an efficient processing method for hot-bent large-angle parts, solving the problems of low forming accuracy (easy springback), low forming efficiency, and low forming qualification rate when titanium alloy bands are bent at both ends by 180°.
[0004] To achieve the above objectives, the present invention adopts the following technical solution: A method for efficiently machining large-angle hot-bent parts includes the following steps: S1, laser cutting blanking, uses sheet metal to obtain multiple strips of material that are flattened and arranged in parallel and spaced intervals, and adjacent strips are connected to form a whole blank. S2, deburring, grinding the burrs on the surface of the entire blank in S1; S3, Remove remelted layer, remove the remelted layer formed by laser cutting around the corresponding opening in the overall billet; S4, Apply protective coating: Spray a thermoforming protective coating onto the entire blank surface to reduce thermoforming friction; S5, thermoforming: The entire blank is placed into a thermoforming mold. First, the first end of the band is bent into a U-shape. Then, the first end of the band that has been bent into a U-shape is bent a second time to obtain the final shape. The bending and forming process of the first end is repeated on the second end of the band. S6, clean the thermoforming protective coating and surface debris from the hoop surface; S7, split, trim and correct the hoop, remove the connection between adjacent hoops, split into individual hoops, and remove the remelted layer and correct the deformation of the individual hoops.
[0005] As an alternative: in S1, the connection width between adjacent hoops does not exceed 1 mm.
[0006] As an alternative: In S1, the connection positions of the multiple hoops after being flattened include the first end and the second end in the length direction of the hoops, as well as the connection between two adjacent hoops along the width direction of the hoops.
[0007] As an alternative: in S4, the thermoforming protective coating is boron nitride.
[0008] As an alternative: in S5, the thermoforming mold includes a lower template, a first punch, an upper template, a second punch, a round bar, and a top plate, wherein, The upper surface of the lower template includes a U-shaped forming groove for the first bending and a stepped forming surface for the second bending. The top plate is located within the U-shaped groove; The round bar is located at the stepped forming surface; The first punch matches the stepped forming surface and the round bar. Its outer surface includes a first plane corresponding to the horizontal plane in the stepped forming surface and a first inclined plane forming an obtuse angle with the first plane. The outer cylindrical surface of the round bar is located between the first inclined plane and the vertical plane in the stepped forming surface. The second punch matches the U-shaped forming groove, and its outer surface is U-shaped; The lower end of the upper template is connected to the first punch and the second punch, respectively.
[0009] As an alternative, thermoforming molds also include: The sliding plate has its first end connected to the side surface of the lower template, and the two sliding plates are arranged in pairs, located on two opposite side surfaces of the lower template respectively. A ramp, the two ends of which are connected to the second ends of two pairs of sliding plates; A pad, which is installed at the upper end of the upper template; Multiple baffles are installed on the upper surface of the lower template to form a positional constraint when the entire blank is placed on the upper surface of the lower template.
[0010] As an alternative: the bottom of the U-shaped groove has a through hole, and a material unloading screw is inserted into the through hole to lift the top plate upward.
[0011] Alternatively, the slide plate has a through groove along its length, and the slide plate is connected to the side surface of the lower template by two second screws inside the through groove.
[0012] This invention provides a method for batch processing titanium alloy bands in a thermoforming mold, whereby multiple bands are integrally thermoformed without being cut. The bending end of the band is formed in two stages: the first stage forms a "U-shaped" structure, and the second stage forms the final bent state of the band. The first and second bending stages can be performed alternately on the same thermoforming mold, improving processing efficiency. Furthermore, the thermoforming mold utilizes sliding plates, mounting plates, pads, and baffles for processing, allowing multiple bands to be processed from a single sheet of material. This results in band parts with advantages such as good consistency, high yield, and high processing efficiency.
[0013] Compared with traditional titanium alloy band forming methods, the present invention has the following advantages: 1. Improved pass rate: The band parts are processed by thermoforming molds, which greatly improves the pass rate of band parts, and the surface of the parts is free from surface defects such as dents and dents. 2. Increased efficiency: Parts efficiency is increased by 90%. Previously, only one hoop could be processed at a time, but now multiple parts (e.g., 28 parts) can be processed at a time. 3. Reduced costs: Raw material utilization has increased by 37%. Previously, a single sheet (2000*1000) could only yield 70 pieces, but now a single sheet can yield 112 pieces.
[0014] Currently, the processing method of this invention has been used in the field and has achieved the expected results and requirements of the invention. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the two-dimensional structure of the titanium alloy band involved in this invention; Figure 2 This is a schematic diagram of the thermoforming die structure for the band. Figure 3 for Figure 2 View A in the middle; Figure 4 for Figure 2 A three-dimensional image; Figure 5 A schematic diagram showing the forming of the first punch, the second punch, the round bar, the top plate, and the lower template. Figure 6 This is a schematic diagram showing the simultaneous feeding of materials from both sides of a thermoforming mold. Figure 7 A schematic diagram illustrating parallel material cutting into a single billet; In the diagram, 1-lower template; 2-slide plate; 3-first punch; 4-upper template; 5-pad; 6-baffle; 7-second punch; 8-round bar; 9-mount plate; 10-top plate; 11-first screw; 12-second screw; 13-third screw; 14-cylindrical pin; 15-bolt; 16-ejector screw. Detailed Implementation
[0016] The present invention will be further described below with reference to specific embodiments, but it should not be construed as limiting the scope of the subject matter of the present invention to the following embodiments. All modifications, substitutions and alterations made based on ordinary technical knowledge and common practices in the art without departing from the above-described technical concept of the present invention are included within the scope of the present invention.
[0017] like Figures 2-7 As shown, the thermoforming mold used in this invention includes a lower template 1, a sliding plate 2, a first punch 3, an upper template 4, a pad block 5, a baffle 6, a second punch 7, a round bar 8, a mounting plate 9, a top plate 10, a first screw 11, a second screw 12, a third screw 13, a cylindrical pin 14, a bolt 15, and a stripper screw 16.
[0018] The forming principle of the titanium alloy band in this invention is as follows: Multiple bands are cut from a single sheet of material and unfolded into a flat surface. For example, the sheet is laser-cut to cut the band parts in parallel, allowing multiple bands (28 in this embodiment) to be unfolded into a flat surface and arranged in parallel, spaced rows. Figure 7 As shown, the width of each hoop joint is no more than 1mm, and the joint includes... Figure 7 The uppermost and lowermost points, as well as the spaces between adjacent hoops, ensure that multiple hoops can be easily separated later while forming a single integral blank, ensuring that each hoop part within the integral blank does not wobble. After laser cutting, the integral blank is then hot-bent. The hot bending is divided into two forming stages. For the same end of the integral blank, the first bending is a "U-shape," and the second forming is the final state of the hoop part. The two forming stages are performed on opposite sides of the same set of thermoforming molds, thus allowing for alternating forming of the hoop parts and accelerating processing efficiency.
[0019] To achieve the above objectives, the present invention is implemented through the following technical solution: (1) Laser cutting: Many parts are cut in parallel. The width of the connection between the belted parts is no more than 1mm. The overall shape of the blank after laser cutting is shown in the figure. Figure 7 ; (2) Deburring: Grind the surface burrs of the same row of hoop parts to avoid affecting the positioning during subsequent thermoforming; (3) Remove the remelted layer: remove Figure 7 The remelted layer around the hole formed during laser cutting; (4) Apply boron nitride: Apply a protective coating evenly to the surface of the entire row of band parts to reduce friction between the band parts and the thermoforming mold; (5) Thermoforming: Place the entire row of hoop parts on the first forming side, then place the hoop parts that have been formed into the first "U" shape on the second forming side, and then alternate forming them in sequence; The specific process is as follows: Figures 4-6 As shown, firstly Figure 7 The hoop parts are laid flat Figure 4 The clamping part is pushed to the left onto the right-side mounting plate 9 (mounted on the sliding plate 2 by the first screw 11). The clamping part touches multiple baffles 6 on the lower template 1 (mounted on the upper surface of the lower template 1 by the third screw 13). These baffles 6 restrict the position of the clamping part on the lower template 1 in both length and width, ensuring that the bending position of the clamping part is precisely aligned with the second punch 7 and the U-shaped forming groove. Once aligned, the upper template 4 moves downwards, pressing the second punch 7 into the U-shaped forming groove, bending the first end of the clamping part into a U-shape. Then, the upper template 4 moves upwards, and the top plate 10 in the U-shaped forming groove moves upwards under the action of the unloading screw 16, pushing the clamping part out of the U-shaped forming groove. The clamping part, having completed its first bending, is then removed, and this end of the U-shaped clamping part is bent a second time. (See details below.) Figure 5 Place the strap parts flat Figure 5 On the left-side mounting plate 9, a round bar 8 is inserted inside the U-shaped end of the clamp part. The clamp part is then pushed to the right. When the clamp part touches the vertical surface of the stepped forming surface on the lower template 1, the upper template 4 is driven to move downward. When the first plane of the first punch 3 presses against the clamp part, its first inclined surface presses the clamp part and the round bar 8 together onto the vertical surface of the stepped forming surface, completing the second bending forming and obtaining... Figure 1 The final bending shape of the middle band component. The spacer block 5 is installed above the upper template 4. Its function is to allow the unbent end of the band component to rotate upwards around the U-shaped forming groove until it approaches the spacer block 5 during the first bending process. In other words, the spacer block 5 provides sufficient forming space for the band component to rotate, preventing interference between the band component and the thermoforming equipment. Bolts 15 are installed on the spacer block 5 for lifting the thermoforming mold.
[0020] The above forming process only describes the bending forming process on one side of the bending forming mold. Since the position of the second bending forming is vacant when the band part is bent in the first bending forming, the first and second bending forming can be carried out simultaneously on the U-shaped forming groove and the stepped forming surface during the process of pressing down the upper template 4.
[0021] (6) Cleaning boron nitride: Wash the boron nitride protective coating on the surface of the belt parts with clean water, and wipe the surface of the belt parts with a scouring pad to remove any remaining boron nitride and other excess substances; (7) Disassemble the hoop parts: Disassemble the entire row of hoop parts into individual hoop parts, remove the remelted layer around the individual hoop parts, and manually correct the deformation caused by the disassembled hoop parts.
[0022] Contents not described in detail in this specification are prior art known to those skilled in the art. Although illustrative specific embodiments of the invention have been described above to facilitate understanding by those skilled in the art, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications are readily apparent to those skilled in the art as long as they fall within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of this invention are protected.
Claims
1. A method for efficient processing of large-angle hot-bent parts, characterized in that, Includes the following steps: S1, laser cutting blanking, uses sheet metal to obtain multiple strips of material that are flattened and arranged in parallel and spaced intervals, and adjacent strips are connected to form a whole blank. S2, deburring, grinding the burrs on the surface of the entire blank in S1; S3, Remove remelted layer, remove the remelted layer formed by laser cutting around the corresponding opening in the overall billet; S4, Apply protective coating: Spray a thermoforming protective coating onto the entire blank surface to reduce thermoforming friction; S5, thermoforming: The entire blank is placed into a thermoforming mold. First, the first end of the band is bent into a U-shape. Then, the first end of the band that has been bent into a U-shape is bent a second time to obtain the final shape. The bending and forming process of the first end is repeated on the second end of the band. S6, clean the thermoforming protective coating and surface debris from the hoop surface; S7, split, trim and correct the hoop, remove the connection between adjacent hoops, split into individual hoops, and remove the remelted layer and correct the deformation of the individual hoops.
2. The efficient processing method for hot-bent large-angle parts according to claim 1, characterized in that: In S1, the connection width between adjacent bands does not exceed 1 mm.
3. The efficient processing method for hot-bent large-angle parts according to claim 1, characterized in that: In S1, the connection positions of the multiple hoops after being flattened include the first end and the second end in the length direction of the hoops, as well as the connection between two adjacent hoops along the width direction of the hoops.
4. The efficient processing method for hot-bent large-angle parts according to claim 1, characterized in that: In S4, the thermoforming protective coating is boron nitride.
5. The efficient machining method for large-angle hot-bent parts according to claim 1, characterized in that: In S5, the thermoforming mold includes a lower template (1), a first punch (3), an upper template (4), a second punch (7), a round bar (8), and a top plate (10), wherein, The upper surface of the lower template (1) includes a U-shaped forming groove for the first bending and a stepped forming surface for the second bending. The top plate (10) is located within the U-shaped groove; The round bar (8) is located at the stepped forming surface; The first punch (3) is matched with the stepped forming surface and the round bar (8). Its outer surface includes a first plane corresponding to the horizontal plane in the stepped forming surface and a first inclined plane forming an obtuse angle with the first plane. The outer cylindrical surface of the round bar (8) is between the first inclined plane and the vertical plane in the stepped forming surface. The second punch (7) matches the U-shaped forming groove, and its outer surface is U-shaped; The lower end of the upper template (4) is connected to the first punch (3) and the second punch (7) respectively.
6. The efficient machining method for hot-bent large-angle parts according to claim 5, characterized in that, Also includes: The first end of the slide plate (2) is connected to the side surface of the lower template (1), and the two slide plates (2) are arranged in pairs, respectively located on two opposite side surfaces of the lower template (1); A ramp (9) is provided, the two ends of which are connected to the second ends of two pairs of sliding plates (2); Pad (5), said pad (5) is installed on the upper end of the upper template (4); Baffles (6), multiple baffles (6) are installed on the upper end face of the lower template (1) to form a position constraint when the whole blank is placed on the upper end face of the lower template (1).
7. The efficient processing method for hot-bent large-angle parts according to claim 5, characterized in that: The bottom of the U-shaped groove has a through hole, and a discharge screw (16) is inserted into the through hole to lift the top plate (10) upward.
8. The efficient processing method for hot-bent large-angle parts according to claim 6, characterized in that: The slide plate (2) has a through groove along its length. The slide plate (2) is connected to the side surface of the lower template (1) by two second screws (12) in the through groove.