Finite element simulation method for drawing of stainless steel floor drain

Abstract

The invention belongs to the technical field of steel and iron material stamping forming, and particularly relates to a stainless steel floor drain drawing finite element simulation method which comprises the following specific steps: S1, measuring the size of a floor drain part needing to be simulated and formed; s2, performing three-dimensional modeling on the part; s3, constructing a three-dimensional model of the stamping die; s4, exporting a file format of an igs format; s5, the igs file is imported into finite element simulation software Dynaform, if the software can automatically recognize all parts, it is indicated that model construction is correct and can be used for simulation, and if not, modification needs to be conducted; s6, the imported mold parts are named; s7, setting the analysis type as 3D analysis; s8, plate material parameters are set; s9, carrying out grid division on the plate; s10, the positions of all tools of the mold are adjusted, and grids are divided; s11, die assembly and deep drawing procedures are set; and S12, submitting operation, and setting a solver of the drawing common step as Dyna-Single. According to the method, simulation characterization of the stainless steel floor drain forming process is achieved, and the reason of drawing cracking of the floor drain can be judged.

Description

Technical Field

[0001] The invention belongs to the technical field of steel material stamping and forming, and in particular relates to a finite element simulation method for deep drawing of a stainless steel floor drain. Background Art

[0002] Deep drawing, also known as drawing, stretching, calendering, etc., refers to a mechanical processing technology that uses a mold to punch a certain shape of flat blank obtained after punching into various open hollow parts or to reduce the diameter of the open hollow blank and increase the height. At present, my country's floor drain manufacturers often experience cracking at the edge of the stretching hole during the production process, which leads to a decline in product quality. However, after the cracking phenomenon occurs, it is difficult to determine the cause of the cracking. It is not known whether it is a problem with the mold or the stamping material. Therefore, the problem of stamping cracking has not been solved for a long time, seriously affecting the production progress and economic benefits. Summary of the invention

[0003] The purpose of the present invention is to provide a finite element simulation method for deep drawing of a stainless steel floor drain, so as to solve the problem that it is difficult to determine the cause of cracking at the edge of the expanded hole in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical scheme: A finite element simulation method for drawing a stainless steel floor drain, the specific steps are as follows: S1: Measure the size of the floor drain parts that need to be simulated; S2: 3D modeling of parts based on the measured dimensional data; S3: Based on the constructed three-dimensional model of the part, a three-dimensional model of the stamping die is constructed using the Boolean operation method; S4: Since the Dynaform finite element simulation software only requires the contact surface of the model, the model needs to be converted into a two-dimensional model without thickness, and finally exported to the igs file format; S5: Import the igs file into the finite element simulation software Dynaform. If the software can automatically identify each part, it means that the model is constructed correctly and can be used for simulation. Otherwise, it needs to be modified. S6: Name the imported mold parts, namely upper mold, lower mold, sheet and blank holder; S7: Create a new sheet metal forming window, set the analysis type to 3D analysis, set the sheet metal thickness, set the process type to double-action forming, and set the working reference surface to upper die / lower die; S8: Set sheet material parameters, including mass density, Young's modulus, Poisson's ratio, hardening rule, and stress-strain curve r value; S9: Mesh the sheet metal, set the mesh type to shell element, and set the element size to 1-1.5mm; S10: Adjust the positions of the various tools of the mold, with the punch at the top, the blank holder, the sheet material, and the die at the bottom, and divide them into grids; S11: Set the die closing and drawing process. In the die closing process, set the upper die and lower die to be stationary, the blank holder to move, and the duration type to tool closing. The gap between the blank holder and the die is 1.1 times the plate thickness. In the drawing process, set the upper die to move, the lower die and the blank holder to be stationary, and the duration is set to displacement control. S12: Submit the operation and set the solver of the drawing step to Dyna-Single.

[0005] Furthermore, in step S1, the width of the floor drain part ranges from 95mm to 105mm, the diameter ranges from 75mm to 85mm, and the opening ranges from 55mm to 65mm.

[0006] Furthermore, in step S8, the mass density is set to 7.2 g / cm 3 -7.8g / cm 3 , Young's modulus is 185GPa-210GPa, Poisson's ratio is 0.28-0.32, and r value is 0.8-1.

[0007] Compared with the prior art, the present invention has the following beneficial effects: This method uses Dynaform sheet metal forming finite element simulation software to simulate the entire process of the floor drain forming process. Combined with the setting of material parameters, mesh division and process settings, it realizes the simulation characterization of the stainless steel floor drain forming process. The cause of the floor drain deep drawing cracking can be determined, which not only speeds up the production progress and increases the economic benefits, but also provides a solution for the future research on stamping product defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 3D modeling of stainless steel floor drain; Figure 2 3D modeling of stamping dies; Figure 3 This is the mesh division diagram of the stamping die; Figure 4 is the forming limit diagram of the blank; Figure 5 is the thickness distribution diagram of the blank; Figure 6 is the stress distribution diagram of the blank of Example 1; Figure 7 This is the stress distribution diagram of the blank in Example 2. DETAILED DESCRIPTION

[0009] The technical solution of the present invention is described in detail below in conjunction with the embodiments and drawings. Example 1

[0010] A finite element simulation method for drawing a stainless steel floor drain, the specific steps are as follows: S1: Measure the dimensions of the floor drain parts to be simulated. The simulated parts are 95mm wide, 75mm in diameter, and 55mm in opening. S2: Based on the measured dimensional data, three-dimensional modeling of the parts is performed, such as Figure 1 As shown; S3: Based on the constructed three-dimensional model of the part, a three-dimensional model of the stamping die is constructed using the Boolean operation method, such as Figure 2 As shown; S4: Since the Dynaform finite element simulation software only requires the contact surface of the model, the model needs to be converted into a two-dimensional model without thickness, and finally exported to the igs file format; S5: Import the igs file into the finite element simulation software Dynaform. If the software can automatically identify each part, it means that the model is constructed correctly and can be used for simulation. Otherwise, it needs to be modified. S6: Name the imported mold parts, namely upper mold, lower mold, sheet and blank holder; S7: Create a new sheet metal forming window, set the analysis type to 3D analysis, set the sheet metal thickness, set the process type to double-action forming, and set the working reference surface to upper die / lower die; S8: Set the sheet material parameters, including the mass density of 7.55g / cm 3 , Young's modulus is 200 GPa, Poisson's ratio is 0.30, hardening rule, and the stress-strain curve r value is 1; S9: Mesh the sheet metal, set the mesh type to shell element, and set the element size; S10: Adjust the positions of the various tools of the mold, with the punch at the top, the blank holder, the sheet metal, and the die at the bottom, and divide the grids, such as Figure 3 As shown; S11: Set the die closing and drawing process. In the die closing process, set the upper die and lower die to be stationary, the blank holder to move, and the duration type to tool closing. The gap between the blank holder and the die is 1.1 times the plate thickness. In the drawing process, set the upper die to move, the lower die and the blank holder to be stationary, and the duration is set to displacement control. S12: Submit the operation, set the solver of the drawing step to Dyna-Single, generate the forming limit diagram of the blank, the thickness distribution diagram of the blank and the stress distribution diagram of the blank, as shown in the figure below. Figure 4 , Figure 5 and Figure 6 shown.

[0011] Stress distribution after simulation Figure 7As shown in the figure, it can be seen that the maximum stress is 1213MPa, which is distributed in the middle of the side wall of the floor drain. The stress on both sides of the maximum stress distribution area gradually decreases, and the stress in the upper bending area is 191MPa. Example 2

[0012] A finite element simulation method for drawing a stainless steel floor drain, the specific steps are as follows: S1: Measure the dimensions of the floor drain parts to be simulated. The simulated parts are 105mm wide, 85mm in diameter, and 65mm in opening. S2: Based on the measured dimensional data, three-dimensional modeling of the parts is performed, such as Figure 1 As shown; S3: Based on the constructed three-dimensional model of the part, a three-dimensional model of the stamping die is constructed using the Boolean operation method, such as Figure 2 As shown; S4: Since the Dynaform finite element simulation software only requires the contact surface of the model, the model needs to be converted into a two-dimensional model without thickness, and finally exported to the igs file format; S5: Import the igs file into the finite element simulation software Dynaform. If the software can automatically identify each part, it means that the model is constructed correctly and can be used for simulation. Otherwise, it needs to be modified. S6: Name the imported mold parts, namely upper mold, lower mold, sheet and blank holder; S7: Create a new sheet metal forming window, set the analysis type to 3D analysis, set the sheet metal thickness, set the process type to double-action forming, and set the working reference surface to upper die / lower die; S8: Set the sheet material parameters, including the mass density of 7.80g / cm 3 , Young's modulus is 210GPa, Poisson's ratio is 0.32, hardening rule, and the stress-strain curve r value is 1; S9: Mesh the sheet metal, set the mesh type to shell element, and set the element size; S10: Adjust the positions of the various tools of the mold, with the punch at the top, the blank holder, the sheet metal, and the die at the bottom, and divide the grids, such as Figure 3 As shown; S11: Set the die closing and drawing process. In the die closing process, set the upper die and lower die to be stationary, the blank holder to move, and the duration type to tool closing. The gap between the blank holder and the die is 1.1 times the plate thickness. In the drawing process, set the upper die to move, the lower die and the blank holder to be stationary, and the duration is set to displacement control. S12: Submit the operation, set the solver of the drawing step to Dyna-Single, generate the forming limit diagram of the blank, the thickness distribution diagram of the blank and the stress distribution diagram of the blank, as shown in the figure below. Figure 4 , Figure 5 and Figure 7 shown.

[0013] Stress distribution after simulation Figure 7 As shown in the figure, it can be seen that the maximum stress is 1213MPa, which is distributed in the middle of the side wall of the floor drain. The stress on both sides of the maximum stress distribution area gradually decreases, and the stress in the upper bending area is 700MPa.

[0014] Cracking during the production process needs to be analyzed from two aspects: First, if the calculated result does not show cracking but it actually does, it means that there are no problems with the processing technology (mold) and material type, and there is a deviation in the material parameters. The problem can be solved by optimizing the material parameters. Second, if the calculated result shows cracking, which is consistent with the actual situation, it requires two aspects of analysis to solve the problem, such as replacing materials or molds. Materials are determined according to user needs and cannot be changed easily. On the premise of ensuring the stability of material parameters, the problem can be solved by changing the processing technology (mold).

Claims

1. A finite element simulation method for drawing a stainless steel floor drain, characterized in that: The specific steps are as follows: S1: Measure the size of the floor drain parts that need to be simulated; S2: 3D modeling of parts based on the measured dimensional data; S3: Based on the constructed three-dimensional model of the part, a three-dimensional model of the stamping die is constructed using the Boolean operation method; S4: Since the Dynaform finite element simulation software only requires the contact surface of the model, the model needs to be converted into a two-dimensional model without thickness, and finally exported to the igs file format; S5: Import the igs file into the finite element simulation software Dynaform. If the software can automatically identify each part, it means that the model is constructed correctly and can be used for simulation. Otherwise, it needs to be modified. S6: Name the imported mold parts, namely upper mold, lower mold, sheet and blank holder; S7: Create a new sheet metal forming window, set the analysis type to 3D analysis, set the sheet metal thickness, set the process type to double-action forming, and set the working reference surface to upper die / lower die; S8: Set sheet material parameters, including mass density, Young's modulus, Poisson's ratio, hardening rule, and stress-strain curve r value; S9: Mesh the sheet metal, set the mesh type to shell element, and set the element size to 1-1.5mm; S10: Adjust the positions of the various tools of the mold, with the punch at the top, the blank holder, the sheet material, and the die at the bottom, and divide them into grids; S11: Set the die closing and drawing process. In the die closing process, set the upper die and lower die to be stationary, the blank holder to move, and the duration type to tool closing. The gap between the blank holder and the die is 1.1 times the plate thickness. In the drawing process, set the upper die to move, the lower die and the blank holder to be stationary, and the duration is set to displacement control. S12: Submit the operation and set the solver of the drawing step to Dyna-Single.

2. The finite element simulation method for deep drawing of a stainless steel floor drain according to claim 1, characterized in that: In the step S1, the width of the floor drain part ranges from 95mm to 105mm, the diameter ranges from 75mm to 85mm, and the opening ranges from 55mm to 65mm.

3. A finite element simulation method for drawing a stainless steel floor drain according to any one of claims 1 or 2, characterized in that: In step S8, the mass density is set to 7.2 g / cm 3 -7.8g / cm 3 , Young's modulus is 185GPa-210GPa, Poisson's ratio is 0.28-0.32, and r value is 0.8-1.

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