A processing and manufacturing method of a long-short intersection integral structure with different rigidities

Abstract

The application provides a processing and manufacturing method of a differential-rigidity long-short intersection integral structure, and belongs to the technical field of aircraft machining and manufacturing. The steps include: designing deformation compensation allowance and rigidity compensation structure; designing integral structure part full-process in-situ machining posture and positioning process boss; determining full-process in-situ machining datum; designing part full-process manufacturing process equipment; compiling numerical control machining program and process specification; carrying out integral structure part machining and manufacturing; and carrying out part inspection. The application can control part deformation, meet the final shape and position requirements of the part, and solve the problems of insufficient part rigidity, poor machining stability, complex process, difficult-to-control deformation, and deviation caused by multi-process and multi-station linkage transformation. The application breaks through the machining and manufacturing difficulties faced in the part production process under the condition of large rigidity difference and uneven length of the integral structure component structure characteristics and multi-process intersection, and provides a technical solution for subsequent more complex machining and manufacturing.

Description

Technical Field

[0001] This invention belongs to the field of aircraft mechanical processing and manufacturing technology, and relates to CNC machining and manufacturing technology, specifically to a processing and manufacturing method for an integral structure with different rigidity and length. Background Technology

[0002] With the improvement of aircraft manufacturing capabilities and the continuous upgrading of aircraft design concepts, large-scale structural components with high integration and integrated structural functions are increasingly common in aerospace structures. These large, integrated structures replace mechanical connections between parts, reduce the number of parts and rivets in aircraft assembly, and significantly reduce aircraft weight. This weight reduction, in turn, greatly improves maneuverability. However, the drawbacks include the high difficulty in machining these integrated structures, low machining efficiency, difficulty in deformation control, and difficulty in guaranteeing the final dimensional accuracy and requirements. The integrated structure with differing rigidity and lengths is the first to design two parts with varying rigidity and lengths as a single unit. The main problems in its machining and manufacturing are as follows:

[0003] 1) The rigidity of the parts varies greatly, and the positional accuracy is difficult to guarantee;

[0004] The differential rigidity, long and short integral structure combines a thin-walled plate with weak rigidity and a thick-walled plate with better rigidity and shorter dimensions into an integral structure with a large difference in rigidity and a combination of long and short dimensions. The size, function and structural stability of the constituent elements differ greatly, and the variable curvature plate with poor rigidity, long dimensions and thin thickness has higher requirements for shape and position.

[0005] 2) The parts are complex to manufacture, involving both hot and cold processes, making deformation difficult to control;

[0006] The fabrication of integral structures with varying rigidity and length involves multiple processes, including machining, welding, heat treatment, sandblasting, and laser shock peening. Machining, welding, and heat treatment all produce deformation, with welding and heat treatment exhibiting significantly greater deformation compared to cold processing. The core challenge and technical bottleneck lies in coordinating these processes to compensate for the deformation during manufacturing and ultimately meet the final design requirements.

[0007] 3) Deviations are easily generated in the transfer of reference points during multi-process and multi-station machining;

[0008] The machining, welding, and heat treatment processes of this integral structure with varying rigidity and length all require specialized tooling and fixtures to ensure stable machining and maintain the correct surface position. Throughout the entire machining process, nearly 10 sets of tooling and fixtures are involved in various processes. Any deviation in the design, transfer, and verification of the multi-station references could lead to the part being scrapped.

[0009] Therefore, a manufacturing method is urgently needed to develop for integral structures with varying rigidity and lengths, capable of controlling component deformation and meeting final form and position requirements. This method would address issues such as insufficient component rigidity, poor machining stability, complex and uncontrollable deformation during the manufacturing process, and deviations easily generated during the transition between multiple processes and workstations. It would overcome the manufacturing challenges faced in producing components with large differences in rigidity and uneven lengths, especially when multiple processes such as machining, welding, and heat treatment are involved. This would provide a technical solution for the subsequent manufacturing of more complex, large-scale, multi-functional integrated aerospace structural components. Summary of the Invention

[0010] To solve the above-mentioned technical problems, the present invention provides a method for processing and manufacturing an integral structure with different rigidity and lengths.

[0011] The present invention adopts the following technical solution:

[0012] A method for manufacturing a composite structure with varying rigidity and lengths, the method comprising the following steps:

[0013] Step 1: Design the deformation compensation margin and stiffness compensation structure.

[0014] 1.1 Determine the full-size compensation allowance H;

[0015] Based on the structural characteristics and welding methods of the integral structural parts, combined with welding finite element analysis, the maximum possible deformation M of the integral structural parts after welding heat treatment is determined. On this basis, double full-size allowance compensation is performed, and the full-size compensation allowance H = 2M is determined, with H rounded up to the nearest integer. The position of allowance compensation is determined according to the part structure and welding method.

[0016] 1.2 Set up a stiffness compensation structure;

[0017] In the components of the overall structural part, a stiffness compensation structure 4 is set on the component with poor stiffness. In combination with the structural characteristics of the part itself, it is preferable to set the stiffness compensation structure 4 on the rib structure of the component with poor stiffness. Its width B = (5~10)×E, where E is the width of the rib where the stiffness compensation structure 4 is located. Then, the length of the stiffness compensation structure 4 is set to (80~140)mm and the height is set to (15~25)mm. The stiffness compensation structure 4 of this size can compensate for stiffness and resist deformation while realizing auxiliary clamping, improving the stability of the part processing process, and facilitating removal during finishing.

[0018] 1.3 Establish a full-size margin digital model of the integral structural parts with stiffness compensation structure;

[0019] Based on the full-size compensation margin H determined in step 1.1 and the stiffness compensation structure 4 determined in step 1.2, a full-size margin digital model of the overall structural parts with stiffness compensation structure is established using 3D modeling software on the basis of the design digital model.

[0020] Step 2: Design the overall structural parts' in-situ machining posture and positioning process bosses.

[0021] 2.1 Determine the overall processing posture based on in-situ manufacturing and the characteristics of each process;

[0022] Based on the assembly and design requirements of the overall structural parts, the machining posture throughout the entire manufacturing process is kept consistent with its final on-machine assembly posture to facilitate the transfer of reference, deformation control, and measurement evaluation throughout the entire process. For machining processes that cannot meet the process requirements under the on-machine posture, other machining postures are adopted, and these machining postures must use the same positioning reference as the on-machine posture.

[0023] 2.2 Determine the positioning process for the entire machining and manufacturing process of the overall structural parts, specifically for boss 5;

[0024] Under the in-situ orientation, the position of the positioning process boss 5 is determined, specifically:

[0025] 2.2.1 In the design model, the plane with the largest projected area of ​​each component in the overall structural part under the assembly reference coordinate system is defined as plane K. Plane K is the plane where the positioning process boss 5 is located. A sketch is drawn on plane K of each component and extruded along the normal of plane K to obtain the positioning process boss 5.

[0026] 2.2.2 Positioning process bosses 5 are set on the outer edge of each component. A positioning process boss 5 is set at a distance of 150-300mm. The positioning process bosses 5 of each component are drawn respectively.

[0027] 2.2.3 The positioning process boss 5 is designed as a bolt hole clamping form. Through holes are set on the positioning process boss 5 as bolt through holes. The tooling used in each process uses bolts to clamp the positioning process boss 5.

[0028] 2.2.4 In combination with the characteristics of welding process, positioning process bosses 5 of each component are set at the beginning and end of the weld of the integral structural parts to ensure the stability of the welding process and the machining stability when the weld arc starting and ending structure is removed by CNC machining after welding.

[0029] 2.2.5 Determine the dimensions of the positioning process boss 5, with the bolt hole located at the center of its width on the side furthest from the part;

[0030] 2.2.6 Using 3D modeling software, based on the full-size margin digital model established in step 1.3, build a full-size margin digital model including the positioning process boss 5 according to the process in step 2.2.

[0031] Step 3: Determine the in-situ machining benchmark for the entire process.

[0032] Of the positioning process bosses 5 determined in the second step, three are selected as the reference process bosses 6 for the entire machining process. Specifically:

[0033] 3.1 The three reference process bosses 6 are selected from the positioning process bosses 5 on the components with poor rigidity;

[0034] 3.2 The triangle A formed by the connecting lines of the three reference process bosses should cover the length and width of the overall structural part to the maximum extent. The larger the area of ​​triangle A, the more conducive it is to stable positioning and clamping. Triangle A should be able to cover the center of gravity of the components with different stiffness in the split stage, and at the same time cover the center of gravity of the overall structural part in the overall stage.

[0035] 3.3 On the two reference process bosses 6 connected by the longest side of triangle A, an additional reference hole 7 is set on each of them. The diameter of the reference hole 7 is D = (10-14) mm.

[0036] 3.4 Use the datum hole 7 to establish a full-process machining coordinate system 10. The direction of the coordinate system is consistent with the direction of the assembly datum coordinate system in the design model. Fine-tune the two datum holes 7 respectively so that the difference between the projected coordinates of the two vertical directions under the full-process machining coordinate system is an integer, which facilitates straightening and alignment during the machining process.

[0037] 3.5 Using 3D modeling software, based on the full-size allowance digital model established in the second step, build a full-size allowance digital model including the in-situ machining datum process boss 6 and datum hole 7 according to the process in the third step.

[0038] Step 4: Design the entire process and equipment for the manufacturing of the parts.

[0039] Using the reference process boss 6 determined in the third step as the positioning reference, the positioning process boss 5 established in the second step as the support surface, and the stiffness compensation structure 4 determined in the first step as the auxiliary clamping, the pre-welding split machining fixture, welding fixture and heat treatment fixture and other process equipment are designed based on the full-size allowance digital model built in the third step.

[0040] Using the reference process boss 6 determined in the third step as the positioning reference, the positioning process boss 5 established in the second step as the support surface, and the stiffness compensation structure 4 determined in the first step as the auxiliary clamping, the overall machining assembly after welding is designed based on the design model of the overall structural parts.

[0041] Each tooling has a pin at the reference hole 7 to position the part, and uses an M16 bolt to tighten the positioning boss 5 to achieve clamping and clamping. A lateral clamping structure and a stiffness compensation structure 4 are used to achieve auxiliary clamping.

[0042] Step 5: Based on the full-size allowance numeral model, design numeral model and various tooling, compile the CNC machining program and process specification for the overall structural parts before and after welding, and perform program verification and simulation analysis of the machining process.

[0043] Step 6: Operate according to the process instructions prepared in Step 5, and use the CNC machining program prepared in Step 5 to carry out the machining and manufacturing of the integral structural parts on the corresponding equipment.

[0044] Step 7: Conduct parts inspection; the overall structural parts processing and manufacturing are completed.

[0045] The effects and benefits of this invention are:

[0046] 1) A reasonable deformation compensation allowance is set, which not only safely encompasses the welding deformation of the parts but also controls the allowance within a minimum range, improving overall processing efficiency. Furthermore, the stiffness compensation structure compensates for the stiffness of weaker parts and can be used for clamping and holding during processing, resisting deformation and improving the stability of the overall structure during processing; 2) The in-situ manufacturing processing posture is more conducive to datum transfer, deformation control, and measurement evaluation throughout the entire manufacturing process. The positioning process bosses can meet the requirements of the positioning clamping force and the constraint force on the parts during welding, achieving stable clamping to suppress part deformation; 3) The design of the entire process processing datum uses a method of connecting lines to form a triangle, and through the center of gravity of the split and overall parts, achieves precise part alignment with the minimum number of datum bosses. Accurate and stable positioning: only three reference process bosses need to be leveled and verified throughout the entire process. The remaining process bosses use adjustable supports, eliminating the need for leveling and greatly improving processing efficiency and reducing manual intervention; 4) Design the entire process processing equipment on the process model that includes the reference process bosses, positioning process bosses and stiffness compensation structure. This enables the parts to maintain the working posture and reference consistency during the entire process of cold and hot process cross manufacturing. At the same time, combined with different process characteristics, under the premise of ensuring reference consistency, the deformation of the parts during the processing can be effectively controlled, and the deformation control and precise manufacturing of the overall structure with different rigidity lengths can be achieved. Attached Figure Description

[0047] Figure 1 Typical differential rigidity long and short intersection overall structure diagram

[0048] Figure 2 In-situ machining posture and positioning process boss diagram

[0049] Figure 3Schematic diagram of benchmark process boss and center of gravity analysis

[0050] Figure 4 Schematic diagram of the clamping stiffness compensation structure of the tooling lateral clamping structure

[0051] In the figure: 1 Side wall plate; 2 Curved wall plate; 3 Connecting weld; 4 Stiffness compensation structure; 5 Positioning process boss; 6 Reference process boss; 7 Reference hole; 8 Reference boss connecting triangle; 9 Center of gravity projection; 10 Full process machining coordinate system; 11 Tooling lateral clamping structure. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. These embodiments are only some, not all, of the embodiments of the present invention. Therefore, the following detailed description of the embodiments provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0053] This embodiment uses a typical component of a composite structure with varying rigidity and intersecting lengths as an example to further illustrate the method. Figure 1 As shown, the material of this typical component is TA15, and the longest part of this typical component is approximately 1800mm long. This typical component designs the side wall plate 1, which has good rigidity and a short dimension, and the curved wall plate 2, which has poor rigidity and a long dimension, into an L-shaped integral structure. The two parts are connected by a connecting weld 3 at the intersection. The specific structural form is as follows. Figure 1 As shown. The specific implementation process of this typical part processing and manufacturing method is as follows:

[0054] 1. Design deformation compensation margin and stiffness compensation structure 4.

[0055] 1) The full-size compensation allowance is set at 3mm;

[0056] Based on the structural characteristics of this typical part and the electron beam welding method, and combined with processing experience and welding finite element analysis, the maximum deformation M of this typical part after welding and heat treatment is predicted to be about 1.3 mm. The allowance after double compensation of the process model is 2.6 mm on one side. After rounding up, the full-size one-side compensation allowance H is determined to be 3 mm.

[0057] 2) Determine that the stiffness compensation structure 4 is located above the stiffeners of the relatively weak curved wall panel 2, and design it as a cube with dimensions of 100mm×20mm×20mm;

[0058] The stiffness compensation structure 4 is placed on the curved wall panel 2, which has lower rigidity. Taking into account the structural feature of the curved wall panel 2 having ribs on one side, the stiffness compensation structure 4 is positioned above the rib structure. The width of the rib where the stiffness compensation structure 4 is located is E = 2mm, and the width of the stiffness compensation structure 4 is set to B = 10 × E = 20mm. Its length is set to 100mm, and its height is set to 20mm. The overall dimensions of the stiffness compensation structure 4 are 100mm × 20mm × 20mm.

[0059] 3) Establish a full-size margin digital model of a typical component with a stiffness compensation structure;

[0060] Based on the full-size compensation margin and stiffness compensation structure 4, using 3D modeling software, a full-size margin digital model of a typical component with stiffness compensation is established based on the design digital model, such as... Figure 1 As shown.

[0061] 2. Design the posture and positioning process boss for the entire process in-situ machining.

[0062] 1) Determine the processing posture throughout the entire process based on in-situ manufacturing and the characteristics of each process. Except for the heat treatment process, the remaining processes are consistent with the assembly posture.

[0063] Based on the assembly and design requirements of typical parts, the machining postures of the split machining, integral machining and welding processes in the entire part processing are kept consistent with their original postures after final on-machine assembly; in view of the deformation control requirements of the heat treatment process, the machining posture is determined to be V-shaped, which is more conducive to deformation control, and the same positioning reference is used for the machining posture and the original posture.

[0064] 2) Determine the positioning boss 5 in the entire process of machining and manufacturing;

[0065] The position of the positioning process boss 5 is determined using the following method under in-situ machining posture:

[0066] a) Based on the processing posture, the curved panel 2 is basically parallel to the horizontal plane of the aircraft, and the plane K1 where its positioning process boss 5 is located is the horizontal working surface of the fuselage. The side panel 1 is basically along the direction perpendicular to the ground, and the plane K2 where its positioning process boss 5 is located is a vertical plane;

[0067] b) Positioning process bosses 5 are set around the part at intervals of 150-300mm, so that they are basically evenly distributed.

[0068] c) The positioning process boss 5 is designed as a bolt hole clamping form. A Φ18 through hole is set on the process boss as a bolt through hole, and an M16 bolt is used for clamping.

[0069] d) Based on the characteristics of the welding process, positioning process bosses 5 are set at the beginning and end of the connecting weld 3 to ensure the stability of the welding process and the stability of the CNC machining removal of the arc initiation and termination segments after welding.

[0070] e) The positioning process boss 5 has a width of 50mm and a length of 55mm. The bolt hole is located on the side of the boss away from the part, at the center of the boss width, and 5mm away from the edge of the boss.

[0071] f) In the in-situ orientation, based on the full-size margin digital model with stiffness compensation, construct a full-size margin digital model including the positioning process boss 5, locally as follows: Figure 2 As shown.

[0072] 3. Determine the in-situ machining benchmark for the entire process.

[0073] In the positioning process bosses 5 of the curved wall panel 2, three locations are selected as the machining reference process bosses 6 for the entire process, as follows:

[0074] a) Select three of the positioning process bosses 5 on the two end faces of the curved wall panel 2 along the length direction as the reference process bosses 6.

[0075] b) Connecting the centers of the three reference process bosses 6 forms a triangle 8;

[0076] c) Use 3D model viewing software to analyze the center of gravity position of curved wall panel 2 and typical parts. In both the split and integral states, the center of gravity projection 9 of the part on the plane where triangle 8 is located is within triangle 8.

[0077] d) Set reference holes 7 with a diameter of D = 12 mm on the two reference process bosses 6 connected by the longest side of triangle 8.

[0078] e) Establish a full-process machining coordinate system 10 on the two reference holes 7. The direction of the coordinate system is consistent with the direction of the assembly reference coordinate system in the design model. The hole spacing of the reference holes 7 in the X and Y directions on the left side of the system is 1810mm and 390mm, respectively. Figure 3 As shown.

[0079] 4. Design the entire process and equipment for the machining and manufacturing of parts.

[0080] Using the reference process boss 6 as the positioning reference, the positioning process boss 5 as the support surface, and the stiffness compensation structure 4 as the auxiliary clamping, the pre-welding split machining fixture, welding fixture and heat treatment fixture are designed based on the full-size allowance and stiffness compensation digital model.

[0081] The tooling is in two places Setting at reference hole 7 The variable diameter pins are used to position the parts, and the M16 bolts are used to tighten the positioning boss 5 for clamping. A lateral clamping structure 11 and a clamping stiffness compensation structure 4 are used for auxiliary clamping. Figure 4 As shown.

[0082] 5. Based on the full-size allowance and stiffness compensation model of typical parts, design model and tooling, compile CNC machining programs and process specifications before and after welding, and perform program verification and simulation analysis of the machining process.

[0083] 6. Operate according to the process instructions and use the prepared CNC machining program to carry out the machining and manufacturing of typical components with different rigidity and long and short intersection structures on the corresponding equipment.

[0084] 7. Check the dimensions and positional accuracy, and complete the processing and manufacturing of typical components of the structural components with different rigidity and length.

Claims

1. A method for processing and manufacturing an integral structure with varying rigidity and lengths, characterized in that, The specific steps of the processing and manufacturing method are as follows: Step 1: Design the deformation compensation margin and stiffness compensation structure; 1.1 Determine the full-size compensation allowance H; Based on the structural characteristics and welding methods of the integral structural parts, combined with welding finite element analysis, the maximum possible deformation M of the integral structural parts after welding heat treatment is determined. On this basis, double full-size allowance compensation is performed, and the full-size compensation allowance H=2M is determined, with H rounded up to the nearest integer. 1.2 Set up a stiffness compensation structure; Stiffness compensation structures are set on the components with poor stiffness in the overall structural parts (4). 1.3 Establish a full-size margin digital model of the integral structural parts with stiffness compensation structure; Based on the full-size compensation margin H determined in step 1.1 and the stiffness compensation structure (4) determined in step 1.2, a full-size margin digital model of the overall structural parts with stiffness compensation structure is established on the basis of the design digital model. Step 2: Design the overall structural parts' in-situ machining posture and positioning process bosses throughout the entire process; 2.1 Determine the overall processing posture based on in-situ manufacturing and the characteristics of each process; Based on the assembly and design requirements of the overall structural parts, the processing posture of the entire manufacturing process is kept consistent with its final on-site posture after assembly. 2.2 Determine the positioning process of the entire process of machining and manufacturing of the overall structural parts, including the boss (5); Under the in-situ posture, determine the position of the positioning process boss (5); Step 3: Determine the in-situ machining benchmark for the entire process; In the second step, three of the positioning process bosses (5) are selected as the reference process bosses (6) for the entire process. Step 4: Design the entire process and equipment for the part's machining and manufacturing; Using the reference process boss (6) determined in the third step as the positioning reference, the positioning process boss (5) established in the second step as the support surface, and the stiffness compensation structure (4) determined in the first step as the auxiliary clamping, the pre-welding split machining fixture, welding fixture and heat treatment fixture are designed based on the full-size allowance digital model built in the first step. Using the reference process boss (6) determined in the third step as the positioning reference, the positioning process boss (5) established in the second step as the support surface, and the stiffness compensation structure (4) determined in the first step as the auxiliary clamping, the overall machining assembly after welding is designed based on the design model of the overall structural parts. Each tool is positioned by setting a pin at the reference hole (7), and the positioning process boss (5) is clamped by using bolts to achieve clamping and clamping. The lateral clamping structure is used to clamp the stiffness compensation structure (4) to achieve auxiliary clamping. Step 5: Based on the full-size allowance digital model, design digital model and various tooling, compile the CNC machining program and process specification for the overall structural parts before and after welding, and perform program verification and simulation analysis of the machining process; Step 6: Operate according to the process instructions prepared in Step 5, and use the CNC machining program prepared in Step 5 to carry out the machining and manufacturing of integral structural parts on the corresponding equipment; Step 7: Conduct parts inspection; the overall structural parts processing and manufacturing are completed.

2. The method for manufacturing a differentially rigid, long-short intersecting integral structure according to claim 1, characterized in that, In step 1.1, the position of the allowance compensation is determined based on the part structure and welding method.

3. The method for processing and manufacturing a differentially rigid, long-short intersecting integral structure according to claim 1, characterized in that, In step 1.1, for machining processes that cannot meet the process requirements in the in-situ posture, other machining postures are adopted, and the machining postures must adopt the same positioning reference as the in-situ postures.

4. The method for processing and manufacturing a differentially rigid, long-short intersecting integral structure according to claim 1, characterized in that, In step 1.2, a stiffness compensation structure (4) is set on the stiffener structure of the stiffness difference component.

5. The method for processing and manufacturing a differentially rigid, long-short intersecting integral structure according to claim 4, characterized in that, The width of the stiffness compensation structure (4) is B = (5~10) × E, where E is the width of the stiffness compensation structure (4), the length of the stiffness compensation structure (4) is set to 80~140mm, and the height is set to 15~25mm.

6. The method for manufacturing a differentially rigid, long-short intersecting integral structure according to claim 1, characterized in that, Step 2.2 specifically refers to: 2.2.1 In the design model, the plane with the largest projected area of ​​each component in the overall structural part under the assembly reference coordinate system is defined as plane K. Plane K is the plane where the positioning process boss (5) is located. Draw a sketch on the plane K of each component and stretch it along the normal of plane K to obtain the positioning process boss (5). 2.2.2 Positioning process bosses (5) are set at the edges of the outer shapes of each component; 2.2.3 The positioning process boss (5) is designed as a bolt hole clamping form. A through hole is set on the positioning process boss (5) as a bolt through hole. The tooling used in each process uses bolts to clamp the positioning process boss (5). 2.2.4 In combination with the characteristics of welding process, positioning process bosses (5) are set at the beginning and end of the weld seam of the integral structural parts. 2.2.5 Determine the dimensions of the positioning process boss (5), with the bolt hole located at the center of its width on the side furthest from the part; 2.2.6 Based on the full-size margin model established in step 1.3, build a full-size margin model including the positioning process boss (5) according to the process in step 2.

2.

7. The method for manufacturing a differentially rigid, long-short intersecting integral structure according to claim 6, characterized in that, The positioning process bosses (5) are spaced 150-300mm apart.

8. The method for manufacturing a differentially rigid, long-short intersecting integral structure according to claim 1, characterized in that, The third step is as follows: 3.1 Select three reference process bosses (6) from the positioning process bosses (5) on the component with poor rigidity. 3.2 The triangle A formed by the connecting lines of the three reference process bosses should cover the length and width of the overall structural part to the maximum extent, and triangle A should be able to cover the center of gravity of the component with stiffness difference in the split stage, and at the same time cover the center of gravity of the overall structural part in the overall stage. 3.3 On the two reference process bosses (6) connected by the longest side of triangle A, a reference hole (7) is set separately. 3.4 Use the reference hole (7) to establish the full-process machining coordinate system (10). The direction of the coordinate system is consistent with the direction of the assembly reference coordinate system in the design model. Adjust the two reference holes (7) respectively so that the difference between the projection coordinates of the two vertical directions under the full-process machining coordinate system is an integer. 3.5 Based on the full-size allowance model established in the first step, build a full-size allowance model including the in-situ machining reference process boss (6) and reference hole (7) according to the process of the third step.

9. The method for manufacturing a differentially rigid, long-short intersecting integral structure according to claim 8, characterized in that, The diameter of the reference hole (7) is D=10-14mm.

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