Method for rapidly extracting bending forming result of aviation pipe

Abstract

The invention relates to a rapid extraction method for an aviation pipe bending forming result, and belongs to the field of aeronautical manufacturing engineering / digital information. A simulation model of a rotary traction bending forming die is constructed in ABAQUS software, material parameters of a pipe and the die need to be set in pretreatment, forming analysis steps are defined, the contact type between the pipe and a forming tool is set, and mesh generation is conducted on the formed pipe and the tool. And submitting and calculating to obtain a conduit bending forming simulation result, and obtaining important data such as forming deviation, forming stress and strain and the like. According to the method, the forming deviation and the stress strain of the guide pipe part are rapidly analyzed, the setting difficulty of finite element analysis is greatly reduced, and a theoretical basis is provided for safety and reliability evaluation after the guide pipe is installed while the pipeline forming quality prediction and control are guaranteed.

Description

Technical Field

[0001] The invention relates to a method for quickly extracting bending forming results of aviation pipes, and belongs to the field of aviation manufacturing engineering / digital information. Background Art

[0002] The pipe forming process usually uses straight pipes as the initial blanks, and is processed and manufactured according to the bending curvature required by the design through various plastic bending forming processes. During the forming process, the forming results of pipe parts will inevitably deviate from the theoretical design, and are prone to cross-sectional flattening, changes in pipe wall thickness, changes in bending radius and bending angle, and even serious forming defects such as wrinkling and cracking. These forming deviations will affect the stiffness and strength of the conduit to varying degrees, and thus affect the overall strength of the pipeline.

[0003] At present, the numerical simulation analysis of the strength of aircraft pipeline systems mostly takes the theoretical model of the pipeline as the analysis object, without considering the influence of the processing results during the pipe bending process on the mechanical properties of the pipeline. As a result, there are certain deviations in the analysis of the overall strength and fatigue of the pipeline, which affects the accuracy of the prediction of strength failures such as pipeline damage and cracking and the analysis of high-risk areas.

[0004] Therefore, how to accurately analyze the tube bending results and obtain important parameters such as forming deviation, forming stress and strain has become an urgent problem to be solved. Summary of the invention

[0005] The invention proposes a rapid extraction method of aviation tube bending forming results based on ABAQUS finite element software, and the method is suitable for rotary traction bending and stretch bending forming process.

[0006] The technical solution of the present invention is as follows:

[0007] The method for quickly extracting the bending results of aviation pipes is as follows:

[0008] Overall idea: In CATIA software, extract the center line of the catheter, calculate the catheter's bending radius, bending angle, rotation angle, straight pipe section feed distance, catheter start point and end point and other forming parameters. Construct a simulation model of the rotary traction bending forming die in ABAQUS software. Pre-processing requires setting the material parameters of the pipe and die, defining the forming analysis step, setting the contact type between the pipe and the forming tooling, and meshing the forming pipe and tooling. After submitting the calculation, obtain the catheter bending forming simulation results, and obtain important data such as forming deviation, forming stress and strain.

[0009] Step 1: In CATIA software, export the catheter digital model in .stp format, extract the center line of the catheter, and calculate the catheter's bending radius, bending angle, rotation angle, feed distance, starting point and end point, outer diameter and inner diameter, catheter length and other forming parameters;

[0010] Step 2: In ABAQUS finite element software, perform parametric rapid modeling of the rotary traction forming tooling, including the bending die, clamping die, pressing die, anti-wrinkle die, mandrel, and ball core. Set basic parameters such as the bending die parameters, clamping die parameters, pressing die parameters, anti-wrinkle die parameters, mandrel parameters, and ball core parameters of the forming die;

[0011] Step 3: Complete the finite element pre-processing work, set the material parameters of the pipe (material brand, conduit outer diameter D, conduit inner diameter d, conduit length L, etc.), import the stress-strain data obtained from the pipe tensile test (obtained from the metal pipe tensile test), set the cross-section type and unit type of the pipe, define the forming analysis step (through the bending radius, bending angle, rotation angle, feed distance, starting point and end point of the conduit calculated in step 1, determine the motion path of the pipe bending forming, including feeding, bending, rotation and other processes, until all pipe sections are set), set the material type of the rotary traction forming tooling (set to rigid body type), set the contact type (surface contact) and friction coefficient and contact gap between the pipe and the forming tooling, mesh the formed pipe and tooling (the mesh size is determined according to the analysis accuracy), etc.

[0012] Step 4: Create and start a job, set the job type to full analysis, use multi-processor parallel analysis to improve the calculation speed, obtain the simulation results of the catheter bending forming, and obtain important data such as forming deviation, forming stress and strain.

[0013] A fast algorithm for extracting spatial geometric parameters of catheters

[0014] In CATIA software, the catheter digital model in .stp format is exported, and the center line of the catheter is extracted using the sheet metal bending forming approximation algorithm. The bending radius, bending angle, rotation angle, straight pipe section feed distance, and the starting point and end point of the catheter are calculated based on the center line.

[0015] Assume that the coordinates of the starting and ending points of the first straight pipe section of the pipe fitting are:

[0016] P1: (x1, y1, z1)

[0017] P2: (x2, y2, z2)

[0018] Assume that the coordinates of the starting and ending points of the second straight pipe section of the pipe fitting are:

[0019] P3: (x3, y3, z3)

[0020] P4: (x4, y4, z4)

[0021] Then the feed of the first straight pipe section is:

[0022]

[0023] From the above 4 points, we can get the vector:

[0024]

[0025] Assume that the angle between the first and second straight pipe sections is θ1, then:

[0026]

[0027] The bending angle

[0028] Bending radius

[0029] Assume that the plane determined by the three points P1, P2, and P3 is α1, then the plane equation is:

[0030] ax+by+cz+d=0

[0031] in:

[0032] a=(y2-y1)*(z3-z1)-(y3-y1)*(z2-z1)

[0033] b=(z2-z1)*(x3-x1)-(z3-z1)*(x2-x1)

[0034] c=(x2-x1)*(y3-y1)-(x3-x1)*(y2-y1)

[0035] Assume the coordinates of the starting and ending points of the third straight pipe section are:

[0036] P5: (x5, y5, z5)

[0037] P6: (x6, y6, z6)

[0038] The plane determined by the second and third straight pipe sections is α2, and the plane equation is:

[0039] a1x+b1y+c1z+d1=0

[0040] in:

[0041] a1=(y4-y3)*(z5-z3)-(y5-y3)*(z4-z3)

[0042] b1=(z4-z3)*(x5-x3)-(z5-z3)*(x4-x3)

[0043] c1=(x4-x3)*(y5-y3)-(x5-x3)*(y4-y3)

[0044] The pipe rotation angle Then the feed of the second straight pipe section is:

[0045]

[0046] The vector is determined by the four points P3, P4, P5, and P6:

[0047]

[0048] Assume that the angle between the second and third straight pipe sections is θ2, then:

[0049]

[0050] Bending radius

[0051]

[0052] And so on, calculate the parameters of all pipe segments.

[0053] Parametric rapid modeling of rotary traction forming tooling

[0054] Rotary traction bending forming tooling (such as Figure 1 As shown), it mainly includes a core shaft 1, a clamping block 2, a spherical core 3, an anti-wrinkle block 4 and a clamping block 2 to fix the pipe 5, and a pulling die 7 is arranged in the tangential direction of the outer edge of the rotary bending die 6. The pulling die 7 and the rotary bending die 6 rotate together around the axis of the rotary bending die at the same angular velocity to provide a bending moment for the pipe. At the same time, the pipe is bent along the outer surface of the rotary bending die 6 driven by friction. By applying additional axial tension to the pipe on the basis of bending under pure bending moment, additional tensile stress is generated to partially offset the tangential compressive stress generated by the bending moment on the concave side of the pipe, thereby reducing the thickness increase of the concave side wall of the pipe during the bending process and inhibiting wrinkling of the pipe. A finite element model of the rotary traction forming tooling is established, which mainly includes a core shaft 1, a clamping block 2, a spherical core 3, an anti-wrinkle block 4, a rotary bending die 6, and a pulling die 7.

[0055] Set the basic parameters of the bending forming die, including bending die parameters, clamping die parameters, pressing die parameters, anti-wrinkle die parameters, mandrel parameters, and ball core parameters. The recommended parameters are as follows:

[0056] Bending die Pressing die die Anti-wrinkle mold Mandrel Core Maximum forming angle Mould length Mould length Mould length Mould length Number of core balls 270 100 100 100 100 3

[0057] Finite Element Pre-processing of Tube Bending

[0058] 1) Set the material parameters of pipes and tooling

[0059] Set the basic parameters of the pipe in ABAQUS software.

[0060] Step 1: Input the material grade of the pipe, the outer diameter D, the inner diameter d, and the length L of the pipe;

[0061] Step 2: Import the stress-strain data obtained from the pipe tensile test:

[0062] The material parameters of the pipe are determined by the stress-strain data obtained from the tensile test of the metal pipe.

[0063] Step 3: Set the section type and unit type of the pipe:

[0064] The cross-section type of pipe 5 can be set to shell element or solid element. When shell element is selected, the element type can be set to triangle, quadrilateral or mixed. When solid element is selected, the element type can be set to tetrahedron, hexahedron or mixed.

[0065] The setting principles are as follows:

[0066] ① When the pipe is a thin-walled pipe, the section type can be set to shell element. Under the premise of ensuring the calculation accuracy, the number of nodes of the finite element model can be effectively reduced, and the calculation time can be saved by 50% to 70%.

[0067] The definition of thin-walled tubes is as follows: the ratio of wall thickness to outer diameter of the tube is no more than 6%, and the wall thickness is 0.6mm to 4.0mm.

[0068] ② When the pipe fitting is not a thin-walled pipe, the section type is set to solid unit.

[0069] Step 4: Set the material type of the rotary traction forming tooling:

[0070] The six components of the rotary traction forming tooling (mandrel 1, clamping block 2, ball core 3, anti-wrinkle block 4, rotary bending die 6, and traction die 7) are all production tools. Their strains are negligible compared to the strains of the pipe products. Therefore, in order to simplify the analysis, reduce the computer computing power requirements, and reduce the error in the appearance of the finished pipe products, the materials of the above six components must be set as rigid bodies.

[0071] 2) Set up the pipe bending analysis step

[0072] The bending radius, bending angle, rotation angle, feed distance, starting point and end point of the conduit calculated in step (1) are used to determine the motion path of the tube bending process. The analysis step parameters are set as follows:

[0073] Analysis step 1: Feed distance L1;

[0074] Analysis step 2: bending radius R1; bending angle θ1;

[0075] Analysis step 3: rotation angle γ1; feed distance L2;

[0076] Analysis step 4: bending radius R2; bending angle θ2;

[0077] Continue until all pipe segments are set.

[0078] 3) Set the contact type between the pipe and the forming tooling to surface contact. The recommended friction coefficient is shown in the table below.

[0079] Bending die Pressing die die Anti-wrinkle mold Mandrel Core Friction coefficient Friction coefficient Friction coefficient Friction coefficient Friction coefficient Friction coefficient 0.01 2.5 0.01 0.01 0.01 0.01 Contact gap Contact gap Contact gap Contact gap 0.01 0.01 0.1 0.1

[0080] 4) The formed pipe and tooling are meshed in ABAQUS software, and the mesh size is determined according to the analysis accuracy.

[0081] 5) Create and start a job, submit the job calculation, obtain the simulation results of the catheter bending forming, obtain important data such as forming deviation, forming stress and strain, and export them in the form of .odb file.

[0082] Beneficial effects of the present invention:

[0083] The present invention proposes a rapid extraction method for tube bending forming results based on ABAQUS finite element software, which realizes the rapid analysis of forming deviation and stress strain of catheter parts, greatly reduces the difficulty of setting up finite element analysis, and provides a theoretical basis for safety and reliability evaluation after catheter installation while ensuring the prediction and control of pipeline forming quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Figure 1 Schematic diagram of rotary traction bending forming tooling;

[0085] Figure 2 Example diagram of rotary traction stretch bending forming pipe;

[0086] Figure 3 Stress-strain curve of pipe. DETAILED DESCRIPTION

[0087] The invention proposes a method for quickly extracting bending forming results of aviation pipes based on a finite element analysis method, and the method is suitable for a rotary traction bending and stretch bending forming process.

[0088] Step 1: After exporting the .stp file using CATIA modeling, extract its geometric parameters. The parameters extracted in this embodiment include the bending radius, bending angle, rotation angle, feed distance, starting point and end point, outer diameter and inner diameter, and catheter length of the catheter, which are calculated according to the following formula: θ1

[0089] Given: the outer diameter of the pipe is 30mm, the inner diameter is 28mm, the wall thickness is 1.0mm, P1: (0, 0, 0), P2: (0, 60, 0), P3: (0, 95.355, 14.645), P4: (0, 182.683, 101.972), then

[0090]

[0091] vector vector

[0092]

[0093] Suppose the plane defined by points P1, P2, and P3 is α1, and the plane equation is: ax+by+cz+d=0

[0094] in:

[0095] a=(y2-y1)*(z3-z1)-(y3-y1)*(z2-z1)=878.7

[0096] b=(z2-z1)*(x3-x1)-(z3-z1)*(x2-x1)=0

[0097] c=(x2-x1)*(y3-y1)-(x3-x1)*(y2-y1)=0

[0098] Given P5: (50, 218.038, 137.328), P6: (100, 218.038, 137.328),

[0099] The plane determined by the second and third straight pipe sections is α2, and the plane equation is:

[0100] a1x+b1y+c1z+d1=0

[0101] in:

[0102] a1=(y4-y3)*(z5-z3)-(y5-y3)*(z4-z3)=0.12

[0103] b1=(z4-z3)*(x5-x3)-(z5-z3)*(x4-x3)=4366.35

[0104] c1=(x4-x3)*(y5-y3)-(x5-x3)*(y4-y3)=-4336.4

[0105]

[0106] Then the feed of the second straight pipe section is:

[0107]

[0108] vector vector

[0109]

[0110] Step 2: Import the tube bending mold and establish the finite element model of the rotary traction forming tooling. The components include the bending mold, clamping mold, pressing mold, anti-wrinkle mold, mandrel, and ball core. Set the basic parameters of the mold according to the recommended values:

[0111] Bending die Compression mold die Anti-wrinkle mold Mandrel Core Maximum forming angle Mould length Mould length Mould length Mould length Number of core balls 270 100 100 100 100 3

[0112] Step 3: Set the material parameters of the pipe

[0113] The pipe material selected in this embodiment is 1Cr18Ni10Ti, with an outer diameter D=30, an inner diameter d=28, and a wall thickness of 1.0 mm. It meets the thin-walled pipe condition, so the conduit is set as a shell unit model, and the unit type is quadrilateral.

[0114] The true stress-strain curve is obtained by tensile test of metal pipes, such as Figure 3 As shown in the figure, it is imported into the Property module of ABAQUS software as the basic performance data of the pipe.

[0115] Step 4: Set the material type of the forming tool:

[0116] Set the material type of the mandrel 1, pressing block 2, ball core 3, anti-wrinkle block 4, rotary bending die 6, and traction die 7 to discrete rigid body, and create RP points for binding respectively.

[0117] Step 5: Establish 5 analysis steps based on the calculation results of step 1:

[0118] Analysis step 1: the starting section of the pipe, and feed L1 = 60mm;

[0119] Analysis step 2: bending point A, bending radius R1 = 50 mm, bending angle θ1 = 45°;

[0120] Analysis step 3: pipe feed L2 = 123.5 mm, pipe circumferential rotation, rotation angle γ1 = 90°;

[0121] Analysis step 4: bending point B, bending radius R2 = 50 mm, bending angle θ2 = 90°;

[0122] Analysis step 5: At the end of the pipe, the pipe rebounds very slightly due to internal stress.

[0123] Step 6: Set the contact type between the tube and the forming tooling to surface contact, and set the friction coefficient as follows:

[0124] Bending die Compression mold die Anti-wrinkle mold Mandrel Core Friction coefficient Friction coefficient Friction coefficient Friction coefficient Friction coefficient Friction coefficient 0.01 2.5 0.01 0.01 0.01 0.01 Contact gap Contact gap Contact gap Contact gap Contact gap Contact gap 0 0 0.01 0.01 0.1 0.1

[0125] Step 7: Set the pipe mesh size to 0.1 and the forming tooling mesh size to 1, and divide the meshes separately.

[0126] Step 8: Use ABAQUS software to create and start a job. The job type is full analysis, using multi-processor parallel analysis.

Claims

1. A method for rapidly extracting bending results of aviation pipes, characterized in that: Here are the steps: Step 1: In CATIA software, export the catheter digital model in .stp format, extract the center line of the catheter, and calculate the catheter's bending radius, bending angle, rotation angle, feed distance, starting point and end point, outer diameter and inner diameter, and catheter length forming parameters; Step 2: In ABAQUS finite element software, perform parametric rapid modeling of the rotary traction forming tooling, including bending die, clamping die, pressing die, anti-wrinkle die, mandrel, and ball core; set the basic parameters of the forming die bending die parameters, clamping die parameters, pressing die parameters, anti-wrinkle die parameters, mandrel parameters, and ball core parameters; Step 3: Complete the finite element pre-processing work, set the material parameters of the pipe, import the stress-strain data obtained from the pipe tensile test, set the section type and unit type of the pipe, define the forming analysis, set the material type of the rotary traction forming tooling, set the contact type, friction coefficient and contact gap between the pipe and the forming tooling, and mesh the formed pipe and tooling; Step 4: Create and start a job, set the job type to full analysis, use multi-processor parallel analysis to improve the calculation speed, obtain the simulation results of the catheter bending forming, and obtain the forming deviation and forming stress and strain data.

2. The method for rapidly extracting the bending results of aviation pipes according to claim 1, characterized in that: In the CATIA software, the specific operation of exporting the catheter digital model in .stp format is as follows: The center line of the conduit is extracted by using a sheet metal bending forming approximation algorithm, and the bending radius, bending angle, rotation angle, straight section feed distance, and starting and ending points of the conduit are calculated through the center line; Assume that the coordinates of the starting and ending points of the first straight pipe section of the pipe fitting are: P1: (x1, y1, z1) P2: (x2, y2, z2) Assume that the coordinates of the starting and ending points of the second straight pipe section of the pipe fitting are: P3: (x3, y3, z3) P4: (x4, y4, z4) Then the feed of the first straight pipe section is: From the above 4 points, we can get the vector: Assume that the angle between the first and second straight pipe sections is θ1, then: The bending angle Bending radius Assume that the plane determined by the three points P1, P2, and P3 is α1, then the plane equation is: ax+by+cz+d=0 in: a=(y2-y1)*(z3-z1)-(y3-y1)*(z2-z1) b=(z2-z1)*(x3-x1)-(z3-z1)*(x2-x1) c=(x2-x1)*(y3-y1)-(x3-x1)*(y2-y1) Assume the coordinates of the starting and ending points of the third straight pipe section are: P5: (x5, y5, z5) P6: (x6, y6, z6) The plane determined by the second and third straight pipe sections is α2, and the plane equation is: a1x+b1y+c1z+d1=0 in: a1=(y4-y3)*(z5-z3)-(y5-y3)*(z4-z3) b1=(z4-z3)*(x5-x3)-(z5-z3)*(x4-x3) c1=(x4-x3)*(y5-y3)-(x5-x3)*(y4-y3) The pipe rotation angle Then the feed of the second straight pipe section is: The vector is determined by the four points P3, P4, P5, and P6: Assume that the angle between the second and third straight pipe sections is θ2, then: Bending radius And so on, calculate the parameters of all pipe segments.

3. The method for rapidly extracting the bending results of aviation pipes according to claim 1 or 2, characterized in that: The parameterized rapid modeling of the rotary traction forming tooling is specifically as follows: The rotary traction bending forming tool comprises a core shaft (1), a clamping block (2), a ball core (3), an anti-wrinkle block (4) and a clamping block (2) for fixing a pipe (5), a traction die (7) being arranged in the tangential direction of the outer edge of the rotary bending die (6), the traction die (7) and the rotary bending die (6) rotating together around the axis of the rotary bending die at the same angular velocity to provide a bending moment for the pipe, and at the same time, the pipe is bent along the outer surface of the rotary bending die (6) driven by the friction force; by applying an additional axial tension to the pipe on the basis of bending under the action of pure bending moment, an additional tensile stress is generated to partially offset the tangential compressive stress generated by the bending moment on the concave side of the pipe, thereby reducing the thickness increase of the concave side wall of the pipe during the bending process and inhibiting the wrinkling of the pipe; A finite element model is established for the rotary traction forming tooling, including a core shaft (1), a pressing block (2), a ball core (3), an anti-wrinkle block (4), a rotary bending die (6), and a traction die (7); Set the basic parameters of the bending forming mold, including bending mold parameters, clamping mold parameters, pressing mold parameters, anti-wrinkle mold parameters, mandrel parameters, and ball core parameters.

4. The method for rapidly extracting the bending results of aviation pipes according to claim 1 or 2, characterized in that: The finite element pre-processing of the pipe bending forming is specifically performed as follows: 1) Set the material parameters of pipes and tooling Set the basic parameters of the pipe in ABAQUS software; Step 1: Input the material grade of the pipe, the outer diameter D, the inner diameter d, and the length L of the pipe; Step 2: Import the stress-strain data obtained from the pipe tensile test: The material parameters of the pipe are determined by the stress-strain data obtained from the tensile test of the metal pipe; Step 3: Set the section type and unit type of the pipe: The cross-section type of pipe (5) can be set to shell element or solid element. When shell element is selected, the element type can be set to triangle, quadrilateral or mixed. When solid element is selected, the element type can be set to tetrahedron, hexahedron or mixed. The setting principles are as follows: ① When the pipe is a thin-walled pipe, the section type can be set to shell element. Under the premise of ensuring the calculation accuracy, the number of nodes of the finite element model can be effectively reduced, and the calculation time can be saved by 50% to 70%; The definition of thin-walled tubes requires the following: the ratio of wall thickness to outer diameter of the tube is no more than 6%, and the wall thickness is 0.6mm to 4.0mm; ② When the pipe is not a thin-walled pipe, the section type is set to solid unit; Step 4: Set the material type of the rotary traction forming tooling: The six components of the rotary traction forming tooling (mandrel (1), clamping block (2), ball core (3), anti-wrinkle block (4), rotary bending die (6), and traction die (7)) are all production tools. Their strains are negligible compared to the strains of the pipe products. Therefore, in order to simplify the analysis, reduce the requirements for computer computing power, and reduce the error of the appearance of the finished pipe products, the materials of the above six components must be set as rigid bodies; 2) Set up the pipe bending analysis step The bending radius, bending angle, rotation angle, feed distance, starting point and end point of the conduit calculated in step (1) are used to determine the motion path of the tube bending process. The analysis step parameters are set as follows: Analysis step 1: Feed distance L1; Analysis step 2: bending radius R1; bending angle θ1; Analysis step 3: rotation angle γ1; feed distance L2; Analysis step 4: bending radius R2; bending angle θ2; Until all pipe sections are set; 3) Set the contact type between the tube and the forming tooling to surface contact; 4) Mesh the formed pipe and tooling in ABAQUS software, and the mesh size is determined according to the analysis accuracy; 5) Create and start a job, submit the job calculation, obtain the simulation results of the catheter bending forming, obtain important data such as forming deviation, forming stress and strain, and export them in the form of .odb file.

5. The method for rapidly extracting bending results of aviation pipes according to claim 3, characterized in that: The finite element pre-processing of the pipe bending forming is specifically performed as follows: 1) Set the material parameters of pipes and tooling Set the basic parameters of the pipe in ABAQUS software; Step 1: Input the material grade of the pipe, the outer diameter D, the inner diameter d, and the length L of the pipe; Step 2: Import the stress-strain data obtained from the pipe tensile test: The material parameters of the pipe are determined by the stress-strain data obtained from the tensile test of the metal pipe; Step 3: Set the section type and unit type of the pipe: The cross-section type of pipe (5) can be set to shell element or solid element. When shell element is selected, the element type can be set to triangle, quadrilateral or mixed. When solid element is selected, the element type can be set to tetrahedron, hexahedron or mixed. The setting principles are as follows: ① When the pipe is a thin-walled pipe, the section type can be set to shell element. Under the premise of ensuring the calculation accuracy, the number of nodes of the finite element model can be effectively reduced, and the calculation time can be saved by 50% to 70%; The definition of thin-walled tubes requires the following: the ratio of wall thickness to outer diameter of the tube is no more than 6%, and the wall thickness is 0.6mm to 4.0mm; ② When the pipe is not a thin-walled pipe, the section type is set to solid unit; Step 4: Set the material type of the rotary traction forming tooling: The six components of the rotary traction forming tooling (mandrel (1), clamping block (2), ball core (3), anti-wrinkle block (4), rotary bending die (6), and traction die (7)) are all production tools. Their strains are negligible compared to the strains of the pipe products. Therefore, in order to simplify the analysis, reduce the requirements for computer computing power, and reduce the error of the appearance of the finished pipe products, the materials of the above six components must be set as rigid bodies; 2) Set up the pipe bending analysis step The bending radius, bending angle, rotation angle, feed distance, starting point and end point of the conduit calculated in step (1) are used to determine the motion path of the tube bending process. The analysis step parameters are set as follows: Analysis step 1: Feed distance L1; Analysis step 2: bending radius R1; bending angle θ1; Analysis step 3: rotation angle γ1; feed distance L2; Analysis step 4: bending radius R2; bending angle θ2; Until all pipe sections are set; 5) Set the contact type between the tube and the forming tooling to surface contact; 6) Mesh the formed pipe and tooling in ABAQUS software, and the mesh size is determined according to the analysis accuracy; 5) Create and start a job, submit the job calculation, obtain the simulation results of the catheter bending forming, obtain important data such as forming deviation, forming stress and strain, and export them in the form of .odb file.

6. The method for rapidly extracting bending results of aviation pipes according to claim 1, 2 or 5, characterized in that: The defined forming analysis is to determine the motion path of the tube bending forming, including the feeding, bending and rotating processes, based on the bending radius, bending angle, rotation angle, feed distance, and forming parameters of the starting and ending points of the conduit calculated in step 1, until all tube sections are set.

7. The method for rapidly extracting bending results of aviation pipes according to claim 3, characterized in that: The defined forming analysis is to determine the motion path of the tube bending forming, including the feeding, bending and rotating processes, based on the bending radius, bending angle, rotation angle, feed distance, and forming parameters of the starting and ending points of the conduit calculated in step 1, until all tube sections are set.

8. The method for rapidly extracting bending results of aviation pipes according to claim 4, characterized in that: The defined forming analysis is to determine the motion path of the tube bending forming, including the feeding, bending and rotating processes, based on the bending radius, bending angle, rotation angle, feed distance, and forming parameters of the starting and ending points of the conduit calculated in step 1, until all tube sections are set.

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