A simulation calculation method, application, device and computer software product for a vulcanization capsule 3D model

Abstract

The present invention relates to the technical field of tire vulcanization, and particularly to a 3D model simulation calculation method, application, device and computer software product for a vulcanization bladder. A 3D model simulation calculation method for a vulcanization bladder, the method comprising the following steps: 1) finite element mesh generation and material property assignment; 2) definition of contact conditions; 3) definition of boundary conditions; 4) three-dimensional simulation calculation of the vulcanization bladder. It can be found from the calculation results of the present invention that the shape of the calculated vulcanization bladder is similar to the final state of shrinkage when the vulcanization bladder is withdrawn from the tire during actual use, that is, the calculation results of the model are of reference significance. Researchers can analyze the maximum stress position and the maximum deformation position of the bladder, that is, the weak points of the bladder, according to the stress distribution of the vulcanization bladder, so as to make targeted improvements to the bladder or fixture structure, and extend the service life of the vulcanization bladder.

Description

Technical Field

[0001] The present invention relates to the technical field of tire vulcanization, and particularly to a 3D model simulation calculation method, application, device and computer software product for a vulcanization bladder. Background Art

[0002] With the development of the tire industry, tire enterprises are becoming more and more strict with product quality and cost control. The vulcanization bladder cooperates with the vulcanizer for tire shaping and vulcanization operations. It is an important consumable auxiliary part in the tire production process and an important control element in vulcanization cost, directly affecting the production efficiency of enterprises. The service life of the vulcanization bladder has always been an important indicator that tire enterprises are extremely concerned about and is the focus of attention of technicians.

[0003] At present, some researchers have found that early mechanical damage that occurs before reaching normal thermal oxygen aging is one of the main problems in the use of vulcanization bladders, and cracks are the main factors causing mechanical damage. When the bladder is repeatedly stretched and deformed under high temperature and high pressure conditions, fine weak points will rapidly expand due to poor mechanical properties, forming micro-cracks, which will lead to early damage of the bladder and greatly reduce the service life of the bladder. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a 3D model simulation calculation method for a vulcanization bladder, which can analyze the stress conditions of the vulcanization bladder during the stretching process, find out the weak points of the bladder's stress deformation, and the calculation results can guide technicians to improve the vulcanization bladder or chuck structure, etc., so as to improve the service life of the vulcanization bladder.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A 3D model simulation calculation method for a vulcanization bladder, the method comprising the following steps:

[0007] 1) Finite element mesh generation and material property assignment

[0008] Draw a sectional view of the vulcanization bladder and the fixture, and coincide the rotation axes of the bladder and the fixture; mesh the drawn sectional view of the bladder, dividing it into quadrilateral elements or triangular elements; assign material properties to each vulcanization bladder element, and set the fixture as a rigid contact body;

[0009] 2) Definition of contact conditions

[0010] Set the contact properties between the vulcanization bladder and the fixture, select the outer surface at the top of the bladder to contact the upper fixture, the outer surface at the top of the bladder is subordinate to the upper fixture surface, the outer surface at the bottom of the bladder contacts the lower fixture surface, and the outer surface at the bottom of the bladder is subordinate to the lower fixture surface;

[0011] 3) Definition of boundary conditions

[0012] The boundary condition is that the upper fixture moves upward, the lower fixture remains stationary, and pressure is applied to the outer surface of the capsule; during the movement process, a certain pressure is applied to the outer surface of the vulcanized capsule, and at the same time, the upper fixture moves upward by a certain distance; at this time, the vulcanized capsule will contact the fixture, the bottom of the capsule is fixed by the lower fixture and cannot move, the upper end of the capsule moves with the upper fixture, and at the same time, it is subjected to a pressure pointing from the outer surface vertically into the capsule inside on the outer surface. The vulcanized capsule will be in a tensile state and shrink inward; according to the calculation results, adjust the range of the pressure application surface, the magnitude of the applied pressure, and the upward movement distance of the upper fixture, repeat this step, and gradually adjust until the upper fixture moves to the specified height;

[0013] 4) Three-dimensional simulation calculation of the vulcanized capsule

[0014] Rotate the two-dimensional model 360 degrees to form a three-dimensional simulation model. Define the Y-axis as the rotation axis, and set the two-dimensional models of the vulcanized capsule and the fixture to rotate 360 degrees around the rotation axis Y-axis, and form a cross-section every 3 degrees; then perform simulation calculations according to step 3), and adjust the pressure on the outer surface and the displacement height of the upper fixture according to the calculation results until the shape of the vulcanized capsule in the calculation termination state.

[0015] Preferably, in step 1), use CAD to draw the cross-sectional views of the vulcanized capsule and the fixture, and align the rotation axes of the capsule and the fixture; save the drawn cross-sectional view of the capsule in dxf format, import it into HyperMesh for mesh division, divide it into quadrilateral elements or triangular elements, and export the file in inp format; open the finite element mesh inp file of the capsule and the dxf file of the fixture structure in Abaqus, and assign material properties to each vulcanized capsule element.

[0016] Preferably, the material properties assigned to each vulcanized capsule element in step 1) include density, elastic modulus, and Poisson's ratio.

[0017] Preferably, the contact properties between the vulcanized capsule and the fixture set in step 2) include normal contact properties and friction coefficient.

[0018] Preferably, in step 2), select the Interaction module in Abaqus, create normal contact properties and friction coefficient in the Interaction Property Manager. Preferably, set the range to 0.1 - 0.35; create Surface-to-surface contact in the Interaction Manager, that is, surface-to-surface contact.

[0019] Preferably, in step 3), Abaqus is used for simulation; first, create steps in the Step module, and create 3 steps according to the movement of the capsule; the first step is named "dis1", the second step is named "Pre2", and the third step is named "Pre3".

[0020] 3.1) Define the boundary conditions for the first step "dis1":

[0021] During the movement process, the upper fixture moves a certain distance in the positive Y-axis direction, and at the same time, a certain pressure is applied to the lower half area of the outer surface of the vulcanized capsule; at this time, the vulcanized capsule will contact the fixture, the bottom of the capsule is fixed by the lower fixture and cannot move, the upper end of the capsule moves with the upper fixture, and at the same time, it is subjected to a pressure perpendicular to the outer surface and pointing to the inside of the capsule on the outer surface. The vulcanized capsule will be in a tensile state and shrink inward; preferably, the specific setting steps are as follows: select the Load module, in Create Boundary Condition, select "dis1" for the step, select Displacement / Rotation for the type, select the upper fixture, check U2, and enter the displacement distance in the input box at the back. More preferably, the displacement distance is set in the range of 220 - 270; in Create Load, select "dis1" for the step, select Pressure for the type, select the lower half of the outer surface of the capsule for the Surface, and enter the applied pressure. More preferably, the pressure is set in the range of 0.05 - 0.15 MPa.

[0022] 3.2) Define the boundary conditions for the second step "Pre2":

[0023] The movement in this step is to apply pressure to the middle and upper parts of the outer surface of the capsule to make the middle and upper parts of the capsule shrink inward; preferably, the specific setting steps are as follows: in Create Load, select "Pre2" for the step, select Pressure for the type, select the middle and upper parts of the outer surface of the capsule for the Surface, and enter the applied pressure. More preferably, the pressure is set in the range of 0.05 - 0.15 MPa.

[0024] 3.3) Define the boundary conditions for the third step "Pre3":

[0025] The movement in this step is to apply pressure to the middle part of the outer surface of the capsule to make the middle part of the capsule shrink inward and adjust the shrinkage shape of the capsule; preferably, the specific setting steps are as follows: in Create Load, select "Pre3" for the step, select Pressure for the type, select the middle part of the outer surface of the capsule for the Surface, and enter the applied pressure. More preferably, the setting range is 0.005 - 0.1 MPa.

[0026] Furthermore, the present invention also discloses a simulation calculation method for the 3D model of the curing bladder, which is used to analyze the maximum stress position and the maximum deformation position of the bladder during the curing bladder design according to the stress distribution of the curing bladder, that is, the weak points of the bladder, so as to make targeted improvements to the bladder or fixture structure and extend the service life of the curing bladder.

[0027] Furthermore, the present invention also discloses a computer device, including a memory, a processor, and a computer program stored on the memory, and the processor executes the computer program to implement the method.

[0028] Furthermore, the present invention also discloses a computer-readable storage medium, on which a computer program or instruction is stored, and when the computer program or instruction is executed by a processor, the method is implemented.

[0029] Furthermore, the present invention also discloses a computer program product, including a computer program or instruction, and when the computer program or instruction is executed by a processor, the method is implemented.

[0030] Due to the above technical solution adopted by the present invention, it can be found from the calculation results that the shape of the calculated curing bladder is similar to the termination state of the curing bladder shrinking and being pulled out from the tire during actual use, that is, the calculation results of the model are of reference significance. Researchers can analyze the maximum stress position and the maximum deformation position of the bladder during this process according to the stress distribution of the curing bladder, that is, the weak points of the bladder, so as to make targeted improvements to the bladder or fixture structure and extend the service life of the curing bladder. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is the design flow chart of the present invention.

[0032] Figure 2 is the two-dimensional finite element model of the curing bladder and fixture of the present invention.

[0033] Figure 3 is the schematic diagram of contact definition of the two-dimensional finite element model.

[0034] Figure 4 is the 3D simulation model of the curing bladder.

[0035] Figure 5 is the shape of the curing bladder in the calculation completed state. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The following will make a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0037] As Figure 1 shown, a simulation calculation method for the 3D model of the curing bladder, the method includes the following steps 1-5.

[0038] 1. Finite Element Mesh Generation and Material Property Assignment

[0039] Use CAD to draw the cross-sectional views of the vulcanization bladder and the fixture, and align the rotation axes of the bladder and the fixture. Since the bladder is an axisymmetric structure, only the finite element mesh needs to be generated based on the cross-sectional view, and then the axisymmetric algorithm can be used. Save the drawn cross-sectional view of the bladder as a dxf file, import it into HyperMesh for mesh generation, divide it into quadrilateral or triangular elements, and export the file as an inp file.

[0040] Open the finite element mesh inp file of the bladder and the dxf file of the fixture structure in Abaqus, assign material properties to each vulcanization bladder element, mainly including density, elastic modulus, and Poisson's ratio, and set the fixture as a rigid contact body, as Figure 2 shown.

[0041] 2. Definition of Contact Conditions

[0042] Set the contact properties between the vulcanization bladder and the fixture. In Abaqus, select the Interaction module, and create normal contact properties and friction coefficients (set the range to 0.1 - 0.35) in the Interaction Property Manager. Create Surface-to-surface contact(Standard) in the Interaction Manager, that is, surface-to-surface contact, set the outer surface at the top of the bladder to contact the upper fixture, the outer surface at the top of the bladder is subordinate to the upper fixture surface, the outer surface at the bottom of the bladder to contact the lower fixture surface, and the outer surface at the bottom of the bladder is subordinate to the lower fixture surface, as Figure 3 .

[0043] 3. Definition of Boundary Conditions

[0044] It mainly includes the definition of boundary content and the application of boundary conditions. To define boundary conditions, it is necessary to understand the motion and constraint states of the components. This invention mainly simulates the motion of the vulcanization bladder. The boundary conditions are mainly that the upper fixture moves upward, the lower fixture remains stationary, and pressure is applied to the outer surface of the bladder.

[0045] This invention uses Abaqus for simulation. First, create steps in the Step module, and create 3 steps according to the motion of the bladder. The first step is named "dis1", the second step is named "Pre2", and the third step is named "Pre3".

[0046] Define the boundary conditions for the first step "dis1". During the movement process, the upper fixture displaces a certain distance in the positive Y-axis direction, and at the same time, a certain pressure is applied to the lower half area of the outer surface of the vulcanization capsule. At this time, the vulcanization capsule will come into contact with the fixture. The bottom of the capsule is fixed by the lower fixture and cannot move, while the upper end of the capsule moves with the upper fixture. At the same time, under the pressure perpendicular to the outer surface and pointing towards the inside of the capsule on the outer surface, the vulcanization capsule will be in a tensile state and contract inward. The specific setting steps are as follows: Select the Load module. In Create Boundary Condition, select "dis1" for the step, select Displacement / Rotation for the type, select the upper fixture, check U2, and enter the displacement distance in the input box at the back (the setting range is 220 - 270). In Create Load, select "dis1" for the step, select Pressure for the type, select the lower half of the outer surface of the capsule for the Surface, and enter the applied pressure (the setting range is 0.05 - 0.15 MPa).

[0047] Define the boundary conditions for the second step "Pre2". The movement in this step is to apply pressure to the middle and upper part of the outer surface of the capsule, causing the middle and upper part of the capsule to contract inward. The specific setting steps are as follows: In Create Load, select "Pre2" for the step, select Pressure for the type, select the middle and upper part of the outer surface of the capsule for the Surface, and enter the applied pressure (the setting range is 0.05 - 0.15 MPa).

[0048] Define the boundary conditions for the third step "Pre3". The movement in this step is to apply pressure to the middle part of the outer surface of the capsule, causing the middle part of the capsule to contract inward and adjusting the contraction shape of the capsule. The specific setting steps are as follows: In Create Load, select "Pre3" for the step, select Pressure for the type, select the middle part of the outer surface of the capsule for the Surface, and enter the applied pressure (the setting range is 0.005 - 0.1 MPa).

[0049] 4. 3D simulation model of the vulcanization capsule

[0050] Mainly rotate the 2D model 360 degrees to form a 3D simulation model, as Figure 4 . Define the Y-axis as the rotation axis, and set the 2D models of the vulcanization capsule and the fixture to rotate 360 degrees around the rotation axis Y-axis. One cross-section is formed every 3 degrees, with a total of 120. Then repeat the content of step 3 for simulation. The shape of the vulcanization capsule at the termination state after the simulation is completed is as Figure 5 shown.

[0051] 5. Result analysis

[0052] From the calculation results, it can be found that the shape of the vulcanizing bladder after calculation is similar to the final state of contraction when the vulcanizing bladder is withdrawn from the tire during actual use, that is, the calculation results of the model are of reference significance. Researchers can analyze the maximum stress position and the maximum deformation position of the bladder during this process, that is, the weak points of the bladder, based on the stress distribution of the vulcanizing bladder, so as to make targeted improvements to the bladder or fixture structure and extend the service life of the vulcanizing bladder.

[0053] The above is the description of the embodiments of the present invention. Through the above description of the disclosed embodiments, those skilled in the art can implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A simulation calculation method for the 3D model of a curing bladder, characterized in that The method includes the following steps: 1) Finite element mesh generation and material property assignment Draw the sectional views of the curing bladder and the fixture, and align the rotation axes of the curing bladder and the fixture; mesh the drawn sectional view of the curing bladder, dividing it into quadrilateral or triangular elements; assign material properties to each curing bladder element, and set the fixture as a rigid contact body; 2) Definition of contact conditions Set the contact properties between the curing bladder and the fixture. Select the outer surface at the top of the curing bladder to contact the upper fixture, and the outer surface at the top of the curing bladder is subordinate to the upper fixture surface. The outer surface at the bottom of the curing bladder contacts the lower fixture surface, and the outer surface at the bottom of the curing bladder is subordinate to the lower fixture surface; 3) Definition of boundary conditions The boundary conditions are that the upper fixture moves upward and the lower fixture remains stationary, and a pressure is applied to the outer surface of the curing bladder; during the movement process, a certain pressure is applied to the outer surface of the curing bladder, and at the same time, the upper fixture moves upward by a certain distance; at this time, the curing bladder will contact the fixture, the bottom of the curing bladder is fixed by the lower fixture and cannot move, the upper end of the curing bladder moves with the upper fixture, and at the same time, it is subjected to a pressure pointing from the outer surface perpendicularly into the interior of the curing bladder on the outer surface, and the curing bladder will be in a tensile state and contract inward; according to the calculation results, adjust the range of the pressure application surface, the magnitude of the applied pressure, and the upward movement distance of the upper fixture, repeat this step, and gradually adjust until the upper fixture moves to the specified height; 4) Three-dimensional simulation calculation of the curing bladder Rotate the two-dimensional model 360 degrees to form a three-dimensional simulation model. Define the Y-axis as the rotation axis, and set the two-dimensional models of the curing bladder and the fixture to rotate 360 degrees around the rotation axis Y, and form a cross-section every 3 degrees; then perform simulation calculations according to step 3), and adjust the pressure on the outer surface and the displacement height of the upper fixture according to the calculation results until the shape of the curing bladder in the calculation termination state.

2. The 3D model simulation calculation method of a vulcanization capsule according to claim 1, characterized in that, In step 1), use CAD to draw the sectional views of the curing bladder and the fixture, and align the rotation axes of the curing bladder and the fixture; save the drawn sectional view of the curing bladder in dxf format, import it into HyperMesh for meshing, divide it into quadrilateral or triangular elements, and export the file in inp format; Open the inp file of the finite element mesh of the curing bladder and the dxf file of the fixture structure in Abaqus, and assign material properties to each curing bladder element.

3. A simulation calculation method for a 3D model of a vulcanization capsule according to claim 1, characterized in that, In step 1), assigning material properties to each curing bladder element includes density, elastic modulus, and Poisson's ratio.

4. A simulation calculation method for a 3D model of a curing bladder according to claim 1, characterized in that In step 2), setting the contact properties between the curing bladder and the fixture includes normal contact properties and friction coefficient.

5. A simulation calculation method for a 3D model of a curing bladder according to claim 2, characterized in that In step 2), select the Interaction module in Abaqus, create normal contact properties and friction coefficient in the Interaction Property Manager; create Surface-to-surface contact in the Interaction Manager, that is, surface-to-surface contact.

6. A simulation calculation method for a 3D model of a curing bladder according to claim 5, characterized in that Create normal contact properties and friction coefficient in the Interaction Property Manager, and set the range to 0.1 - 0.

35.

7. A simulation calculation method for a 3D model of a curing bladder according to claim 1, characterized in that, Step 3) Conduct simulation using Abaqus; First, create steps in the Step module. Create 3 steps according to the movement of the curing bladder; Name the first step "dis1", the second step "Pre2", and the third step "Pre3". 3.1) Define the boundary conditions for the first step "dis1": During the movement process, the upper fixture displaces a certain distance in the positive Y-axis direction, and at the same time, a certain pressure is applied to the lower half area of the outer surface of the curing bladder; At this time, the curing bladder will come into contact with the fixture. The bottom of the curing bladder is fixed by the lower fixture and cannot move. The upper end of the curing bladder moves with the upper fixture. At the same time, it is subjected to a pressure perpendicular to the outer surface and pointing towards the inside of the curing bladder. The curing bladder will be in a tensile state and contract inward. 3.2) Define the boundary conditions for the second step "Pre2": The movement in this step is to apply pressure to the middle and upper parts of the outer surface of the curing bladder to make the middle and upper parts of the curing bladder contract inward; 3.3) Define the boundary conditions for the third step "Pre3": The movement in this step is to apply pressure to the middle part of the outer surface of the curing bladder to make the middle part of the curing bladder contract inward and adjust the contraction shape of the curing bladder.

8. A simulation calculation method for a 3D model of a curing bladder according to claim 7, characterized in that, The specific settings for step 3.1) are as follows: Select the Load module. In Create Boundary Condition, select "dis1" for the step, select Displacement / Rotation for the type, select the upper fixture, check U2, and enter the displacement distance in the input box at the back; In Create Load, select "dis1" for the step, select Pressure for the type, select the lower half of the outer surface of the curing bladder for the Surface, enter the applied pressure, and the pressure setting range is 0.05 - 0.15 MPa.

9. A simulation calculation method for a 3D model of a vulcanization capsule according to claim 7, characterized in that, The specific settings for step 3.2) are as follows: In Create Load, select "Pre2" for the step, select Pressure for the type, select the middle and upper parts of the outer surface of the curing bladder for the Surface, enter the applied pressure, and the pressure setting range is 0.05 - 0.15 MPa.

10. A simulation calculation method for a 3D model of a curing bladder according to claim 7, characterized in that, The specific settings for step 3.3) are as follows: In Create Load, select "Pre3" for the step, select Pressure for the type, select the middle part of the outer surface of the curing bladder for the Surface, enter the applied pressure, and the pressure setting range is 0.005 - 0.1 MPa.

11. A method for simulating and calculating the 3D model of a curing bladder according to any one of claims 1 - 10. This method is used to analyze and calculate the maximum stress position and maximum deformation position of the curing bladder, that is, the weak points of the curing bladder, based on the stress distribution of the curing bladder during the design of the curing bladder, so as to make targeted improvements to the results of the curing bladder or the fixture and extend the service life of the curing bladder.

12. A computer device, comprising a memory, a processor, and a computer program stored on the memory, characterized in that, The processor executes the computer program to implement the method according to any one of claims 1 - 10.

13. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instruction is executed by the processor, it implements the method according to any one of claims 1 - 10.

14. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instruction is executed by a processor, it implements the method described in any one of claims 1 to 10.

Images