Adaptive Temperature Control Method for Drawing Die

Abstract

The present invention relates to the technical field of die stamping, and discloses an adaptive temperature control method for a drawing forming die, aiming to solve the problems of low stamping efficiency and quality defects existing in the existing die during drawing forming. The solution mainly includes: determining the die material and the stamping parameters of the die during drawing forming; constructing a finite element model of the die drawing forming in 3D software, and performing simulation analysis according to the die material and stamping parameters to determine the first surface temperature change ratio and its corresponding first material flow-in change ratio at each point during the die drawing forming; fitting to obtain the functional relationship between the material flow-in change ratio and the surface temperature change ratio; determining the second material flow-in change ratio corresponding to the maximum surface temperature value during the simulation analysis; judging whether the die needs to be cooled during drawing forming, and if so, cooling the die through a cooling device during drawing forming. The present invention avoids die quality defects and improves stamping efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of die stamping, and more particularly to an adaptive temperature control method for a drawing forming die. Background Art

[0002] During the drawing forming process of large automotive panel dies, the sheet metal contacts the upper and lower die surfaces. Under the action of the blank holding force, plastic forming is carried out relying on the stamping load. During this period, a large amount of forming and frictional heat is generated. Especially for parts with deep drawing on the side walls such as wheel covers and inner door panels, the surface quality of the first batch of stampings can meet the accuracy requirements of customers. When the die cavity temperature rises to a certain level, with the increase in the stamping frequency and batch, the temperature of the die blank holder continuously rises. After continuous stamping, the temperature of the blank holder can reach about 300 °C, resulting in a large fluctuation in the sheet metal inflow, leading to varying degrees of appearance defects or quality accidents in parts such as wheel covers and inner door panels. The appearance defects are manifested as scratches or galling defects on the local surface of the product, and the quality accidents are manifested as wrinkling or cracking defects in the side wall step area. In response to the above phenomena, the traditional method is to reduce the stamping production frequency and interrupt the stamping operation to cool the die relying on an external air source. Therefore, the stamping production efficiency is reduced to a certain extent, and when the local temperature rise of the blank holder cannot be controlled, the above-mentioned appearance or quality defects will still occur. Summary of the Invention

[0003] The present invention aims to solve the problems of low stamping efficiency and quality defects existing in the existing die during drawing forming, and proposes an adaptive temperature control method for a drawing forming die.

[0004] The technical solution adopted by the present invention to solve the above technical problems is: an adaptive temperature control method for a drawing forming die, comprising the following steps:

[0005] Step 1: Determine the die material and the stamping parameters of the die during drawing forming. The stamping parameters at least include: stamping load, stamping speed, blank holding force, and friction coefficient;

[0006] Step 2: Construct a finite element model of the die drawing forming in 3D software. Based on the die material and stamping parameters and using the finite element model for simulation analysis, determine the first surface temperature change ratio at each point during the die drawing forming and its corresponding first material inflow change ratio;

[0007] Step 3: Fit the function relationship between the material inflow change ratio and the surface temperature change ratio according to the first temperature change ratio at each point and its corresponding first material inflow change ratio;

[0008] Step 4: Determine the second surface temperature change ratio corresponding to the maximum surface temperature value during simulation analysis, and determine the corresponding second material inflow change ratio based on the second surface temperature change ratio and the functional relationship;

[0009] Step 5: Determine whether the mold needs to be cooled during the drawing forming process according to the second material inflow change ratio. If so, set up a cooling device and cool the mold through the cooling device during the drawing forming process.

[0010] Further, determining whether the mold needs to be cooled during the drawing forming process according to the second material inflow change ratio specifically includes:

[0011] Judge whether the second material inflow change ratio is within a first preset range. If so, determine that the mold needs to be cooled during the drawing forming process; otherwise, determine that the mold does not need to be cooled during the drawing forming process.

[0012] Further, the setting of the cooling device specifically includes:

[0013] When the second material inflow change amount is within the first preset range, judge whether the second material inflow change amount is within a second preset range. If so, set up a medium-low speed cooling device; otherwise, set up a high-speed cooling device.

[0014] Further, the method further includes:

[0015] Divide multiple regions on the mold, respectively determine the maximum temperature value corresponding to each region during simulation analysis, and for the maximum temperature value corresponding to each region, respectively determine its corresponding second material inflow change ratio;

[0016] Judge whether each region of the mold needs to be cooled during the drawing forming process according to the corresponding second material inflow change ratio. If so, set up a cooling device in the corresponding region and cool the corresponding region of the mold through the cooling device during the drawing forming process.

[0017] Further, the method further includes:

[0018] When a cooling device is set up, obtain the critical temperature value that affects the mold performance;

[0019] When the mold is undergoing drawing forming, real-time detect the surface temperature value of the region where the cooling device is set up on the mold. When the surface temperature value is greater than or equal to the critical temperature value, start the corresponding cooling device for cooling; when the surface temperature value is less than the critical temperature value, turn off the corresponding cooling device.

[0020] Further, the method for obtaining the critical temperature value includes:

[0021] A preset critical temperature value; or

[0022] Calculate the temperature change ratio affecting the mold performance according to the preset material inflow change ratio and based on the function relationship, and determine the corresponding critical temperature value according to the temperature change ratio.

[0023] Further, after the surface temperature value of the area where the cooling device is provided on the mold is detected in real time, it further includes:

[0024] Determine the temperature error caused by the natural heat effect, and correct the surface temperature value according to the temperature error.

[0025] Further, the surface temperature of the area where the cooling device is provided on the mold is detected in real time by a resistance temperature sensor, and the temperature error is obtained by calculation. The calculation formula is as follows:

[0026] Δt = KI 2 R;

[0027] In the formula, Δt is the temperature error, K is a coefficient, I is the current passing through the resistance temperature sensor when detecting the surface temperature value, and R is the resistance value of the resistance temperature sensor when detecting the surface temperature value.

[0028] Further, the coefficient is determined by the following method:

[0029] Measure the current I1 passing through the resistance temperature sensor and the resistance R1 of the resistance temperature sensor when the mold is first stamped;

[0030] Increase the current passing through the resistance temperature sensor, and measure the current I n passing through the resistance temperature sensor and the resistance R n of the resistance temperature sensor after the mold is stamped a preset number of times;

[0031] Calculate to obtain the coefficient. The calculation formula is as follows:

[0032]

[0033] In the formula, α is the temperature coefficient of the resistance temperature sensor.

[0034] Further, the cooling device at least includes: a gas source, a cooling pipeline, and a cooling cylinder assembly. The gas source is connected to the cooling cylinder assembly through the cooling pipeline, and the cooling pipeline is embedded inside the mold or in a groove opened on the back of the mold.

[0035] The beneficial effects of the present invention are as follows: For the self-adaptive temperature control method of the drawing die in the present invention, through simulation analysis, it can accurately determine whether the die needs to be cooled during the drawing process. When cooling is not required, the cooling device is not set, thereby improving the stamping efficiency and reducing the stamping cost. When cooling is required, the cooling device is set, which can avoid the quality impact caused by high temperature on the drawing of the die, improve the quality of the die, and further improve the stamping efficiency. By setting the cooling device in the corresponding area of the die, targeted cooling of the high-temperature area of the die can be achieved, improving the accuracy of temperature control. By setting a resistance temperature sensor to collect the surface temperature value of the corresponding area of the die, and automatically starting the cooling device in the corresponding area when the surface temperature value reaches the critical temperature value, and automatically closing the corresponding cooling device when the surface temperature value does not reach the critical temperature value, manual control of the cooling device by the staff is not required. This can not only avoid the energy consumption caused by the cooling device always being in the startup state, but also avoid the quality defects of the die caused by not starting the cooling device, realizing the self-adaptive control of the cooling device, improving the control accuracy, and reducing the manual operation of the staff, further improving the stamping efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 FIG. is a schematic flow chart of the self-adaptive temperature control method of the drawing die according to the embodiment of the present invention;

[0037] Figure 2 FIG. is a schematic structural diagram of the finite element model according to the embodiment of the present invention;

[0038] Figure 3 FIG. is a schematic diagram of the material inflow according to the embodiment of the present invention;

[0039] Figure 4 FIG. is a schematic structural diagram of the cooling device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0041] The present invention aims to propose an adaptive temperature control method for a drawing die to improve the accuracy of temperature control of the die during drawing, thereby reducing stamping costs and improving stamping efficiency. Its main technical scheme includes: determining the die material and the stamping parameters of the die during drawing, the stamping parameters at least including: stamping load, stamping speed, blank holder force and friction coefficient; constructing a finite element model of die drawing in a three-dimensional software, performing simulation analysis based on the die material and stamping parameters and based on the finite element model, determining the first surface temperature change ratio of each point of the die during drawing and its corresponding first material inflow change ratio; fitting the functional relationship between the material inflow change ratio and the surface temperature change ratio according to the first temperature change ratio of each point and its corresponding first material inflow change ratio; determining the second surface temperature change ratio corresponding to the maximum surface temperature value during simulation analysis, and determining the corresponding second material inflow change ratio according to the second surface temperature change ratio and based on the functional relationship; judging whether the die needs to be cooled during drawing according to the second material inflow change ratio, and if so, setting a cooling device, and cooling the die by the cooling device during drawing.

[0042] It can be understood that whether the mold will produce quality defects is correlated with the change in the material inflow of the mold, where the material inflow change indicates the amount of material reduction or increase at a certain point of the mold, and the material inflow change ratio is the ratio between the material inflow change and the total material amount. When the material inflow change ratio is too large, it means that the material inflow change per unit time is large, that is, the greater the degree of deformation of the mold, and when the deformation reaches a certain degree, the mold will produce defects such as scratches, burrs, wrinkles, and cracks. At the same time, the material inflow change ratio is also related to the temperature change ratio, which is the ratio between the temperature change and the temperature value at the previous moment. Based on this, the present invention first conducts simulation analysis by constructing a finite element model of die drawing, and fits the functional relationship between the material inflow change ratio and the temperature change ratio based on the simulation analysis results, and then calculates the material inflow change ratio corresponding to the maximum temperature value during the simulation analysis based on the functional relationship, and judges whether the current die will produce quality defects due to the influence of high temperature when drawing using the current stamping parameters according to the calculated material inflow change ratio. If so, a cooling device is embedded in the die design stage, and the die is cooled by the cooling device when drawing, thereby avoiding the quality impact of high temperature on the die drawing, improving the quality of the die, and further improving the stamping efficiency. If not, there is no need to embed a cooling device, thereby improving the stamping efficiency and reducing the stamping cost.

[0043] Example

[0044] See also Figure 1, the self - adaptive temperature control method for the drawing die according to the embodiments of the present invention includes the following steps:

[0045] Step 1: Determine the die material and the stamping parameters during the drawing of the die. The stamping parameters at least include: stamping load, stamping speed, blank - holding force, and friction coefficient;

[0046] In this embodiment, the die can be a product covering part. For example, side - wall parts such as the wheel cover and the inner door panel of a large - sized automobile. Die materials such as: steel, steel - aluminum alloy, etc. When drawing the die, it is generally necessary to fix the blank - holding ring of the sheet.

[0047] Step 2: Construct a finite - element model of the die drawing in 3D software. Based on the die material and stamping parameters and using the finite - element model for simulation analysis, determine the first surface - temperature change ratio and its corresponding first material - flow - in change ratio at each point during the die drawing;

[0048] Specifically, please refer to Figure 2 , in this embodiment, in 3D software, the designed convex - concave die, blank - holding ring, and sheet - metal model are imported into a general finite - element software to construct a finite - element model of the die drawing. Then, parameters such as die material, stamping load, stamping speed, and blank - holding force are set. Secondly, a radiation analysis step for the die, blank, and the surrounding air is created, and the analysis results of the initial cold - stamping thermal field of the product and the thermal - field forming simulation analysis results under continuous and stable stamping conditions are respectively simulated and analyzed, so as to determine the first surface - temperature change ratio and its corresponding first material - flow - in change ratio at each point during the die drawing.

[0049] Step 3: Fit the function relationship between the material - flow - in change ratio and the surface - temperature change ratio according to the first temperature - change ratio and its corresponding first material - flow - in change ratio at each point;

[0050] Figure 3 shows a schematic diagram of the material - flow - in amount of a blank - holding ring. It can be understood that the greater the inflow amount generated by the plastic deformation during the sheet - metal drawing, the greater the deformation heat and friction heat at this part. After the temperature of the blank - holding ring rises, the friction coefficient during the contact and sliding process with the sheet metal is also greater. Using a quantitative analysis method, on the premise of a certain blank - holding force, when the temperature rises, the effect of the coupling of temperature and plastic - deformation stress is equivalent to the change in the friction coefficient, and the numerical value of the inflow amount of the product - drawing profile under the change of temperature and friction coefficient is obtained, and binomial fitting is performed to eliminate the discrete error value and obtain an accurate function relationship between the material - flow - in change ratio and the surface - temperature change ratio.

[0051] In this embodiment, the function relationship between the material - flow - in change ratio y and the surface - temperature change ratio x is as follows:

[0052] y = 0.02 - 0.12x - 0.001x 2 。

[0053] Step 4: Determine the second surface temperature change ratio corresponding to the maximum surface temperature value during simulation analysis, and determine the corresponding second material inflow change ratio based on the second surface temperature change ratio and the functional relationship;

[0054] In this embodiment, the second surface temperature change ratio corresponding to the maximum temperature value of all points can be selected to calculate the corresponding second material inflow change ratio.

[0055] Step 5: Determine whether the mold needs to be cooled during drawing forming according to the second material inflow change ratio. If so, set a cooling device and cool the mold through the cooling device during drawing forming.

[0056] In order to further improve the accuracy of temperature control, this embodiment further includes:

[0057] Divide multiple regions on the mold, respectively determine the maximum temperature value corresponding to each region during simulation analysis, and for the maximum temperature value corresponding to each region, respectively determine the corresponding second material inflow change ratio;

[0058] Determine whether each region of the mold needs to be cooled during drawing forming according to the corresponding second material inflow change ratio. If so, set a cooling device in the corresponding region and cool the corresponding region of the mold through the cooling device during drawing forming.

[0059] Specifically, this embodiment can divide multiple regions on the mold. For each region, respectively determine the corresponding maximum temperature value during simulation analysis, substitute the maximum temperature value into the functional relationship respectively to calculate the second material inflow change ratio corresponding to each region, and then determine whether a cooling device needs to be set in the corresponding region according to the second material inflow change ratio.

[0060] In this embodiment, determining whether the mold needs to be cooled during drawing forming according to the second material inflow change ratio specifically includes:

[0061] Judge whether the second material inflow change ratio is within a first preset range. If so, determine that the mold needs to be cooled during drawing forming, otherwise determine that the mold does not need to be cooled during drawing forming.

[0062] For example, when the change ratio of the inflow of the second material is less than 1%, it indicates that the influence of temperature on the plastic deformation of the product in this area is small. To save costs, a cooling device may not be set up. When the change ratio of the inflow of the second material is greater than or equal to 1%, it indicates that temperature will affect the plastic deformation of the product in this area. To avoid wrinkling and cracking, a cooling device needs to be set up.

[0063] To further improve the accuracy of temperature control, the cooling device in this embodiment includes a medium-low speed cooling device and a high-speed cooling device. When the change amount of the inflow of the second material is within a first preset range, it is judged whether the change amount of the inflow of the second material is within a second preset range. If so, a medium-low speed cooling device is set up; otherwise, a high-speed cooling device is set up.

[0064] For example, when the change ratio of the inflow of the second material is greater than or equal to 1% and less than or equal to 3%, it indicates that the influence of temperature on the plastic deformation of the product in this area is not very large. To save costs and avoid wrinkling and cracking at the same time, a medium-low speed cooling device is set up. When the change ratio of the inflow of the second material is greater than 3%, it indicates that the influence of temperature on the plastic deformation of the product in this area is very large. To avoid wrinkling and cracking, a high-speed cooling device is set up.

[0065] In this embodiment, when it is determined that a cooling device needs to be set up, the cooling device is pre-embedded in the mold during the design stage of the mold, and the temperature is reduced through the cooling device during the drawing forming of the mold, so as to avoid the quality impact caused by high temperature on the drawing forming of the mold. When it is determined that a cooling device does not need to be set up, there is no need to pre-embed the cooling device, thereby improving the stamping efficiency and reducing the stamping cost.

[0066] When the mold is divided into multiple regions, a separate cooling device is set up for each region that needs to be provided with a cooling device. Figure 4 A schematic diagram showing the setting of cooling devices in three regions respectively is shown. Among them, each cooling device includes: a gas source, a cooling pipeline, and a cooling cylinder assembly. The gas source is connected to the cooling cylinder assembly through the cooling pipeline, and the cooling pipeline is pre-embedded inside the mold or in a groove opened on the back of the mold during the mold design stage.

[0067] In practical applications, compressed air can be used as the cooling medium for the gas source, and a complete constant temperature control loop is formed by connecting a pressure regulating valve, a filter, and a control valve. After the compressed gas is introduced into the cooling cylinder, the gas generates a high-speed swirl, separating the injected low-temperature air flow from the high-temperature air flow inside the blank holder, realizing the cooling and temperature reduction of the blank holder profile area near this channel.

[0068] Among them, when pre-burying the cooling pipeline, two forms can be set. One is that when the binder surface and the body are set as a movable separation type, the binder surface is divided into blocks by steel parts, and grooves are opened on the back of the surface. There is no need to pre-bury steel pipes, and the cooling air circulates in the grooves to achieve constant temperature control. The other is that when the binder is integral, the cooling gas steel pipe is pre-buried into the channel during the casting stage, and the constant temperature control is achieved by relying on the cooling gas in the steel pipe.

[0069] Please refer to Figure 4 , when the die with a cooling device is drawn and formed, a resistance temperature sensor can also be set in the corresponding area, and the start of the cooling device can be controlled according to the surface temperature value detected by the resistance temperature sensor, so as to avoid the cooling device being always in the start state, and further improve the accuracy of temperature control. Please refer to Figure 1 , and the specific process is as follows:

[0070] Step 6: When a cooling device is set, obtain the critical temperature value that affects the die performance;

[0071] Step 7: When the die is drawn and formed, the surface temperature value of the area where the cooling device is set on the die is detected in real time. When the surface temperature value is greater than or equal to the critical temperature value, start the corresponding cooling device for cooling; when the surface temperature value is less than the critical temperature value, turn off the corresponding cooling device.

[0072] Among them, the critical temperature value is the temperature value that affects the die performance. When the temperature reaches the critical temperature value, it means that the die may have defects such as scratches, galling, wrinkling, and cracking. When the temperature does not reach the critical temperature value, it means that the die stamping will not cause quality defects. The critical temperature value can be preset according to experience, or the temperature change ratio that affects the die performance can be calculated based on the preset material flow change ratio and the function relationship, and then the corresponding critical temperature value can be determined according to the temperature change ratio.

[0073] Specifically, 1% can be used as the preset material flow change ratio and substituted into the function relationship to calculate the corresponding temperature change ratio, and then the corresponding critical temperature value can be determined according to the temperature change ratio.

[0074] In actual application, a PT100 of the WZP type can be used as the resistance temperature sensor. The resistance of the resistance temperature sensor changes correspondingly with the change of temperature. The change amount of the resistance is converted into a voltage signal, amplified by the signal amplifier AD623, transmitted to the A / D conversion circuit, and processed by the STC89C52 single-chip microcomputer control system to obtain the surface temperature value of the corresponding area.

[0075] During the die drawing forming process, if the temperature detected by the resistance temperature sensor is greater than or equal to the critical temperature value, it indicates that the temperature at this time will affect the plastic deformation of the product in this area. At this time, control the corresponding cooling device to start and cool down the corresponding area. If the temperature detected by the resistance temperature sensor is less than the critical temperature value, it indicates that the temperature at this time has less influence on the plastic deformation of the product in this area. At this time, control the corresponding cooling device to close, thereby realizing the adaptive control of the cooling device.

[0076] In this embodiment, after obtaining the surface temperature value of the corresponding area detected by the resistance temperature sensor, it can also be sent to the display device for display, so as to facilitate the staff to understand the real-time temperature.

[0077] By automatically starting the corresponding cooling device when the surface temperature value is greater than or equal to the critical temperature value, and automatically closing the corresponding cooling device when the surface temperature value is less than the critical temperature value, there is no need for the staff to manually control the cooling device, thus realizing the adaptive control of the cooling device, improving the control accuracy, and reducing the manual operation of the staff, further improving the stamping efficiency.

[0078] Due to the natural heat effect, there is a certain error in the surface temperature value detected by the resistance temperature sensor. In order to avoid the temperature detection error caused by the natural heat effect and further improve the accuracy of temperature control, this embodiment further includes:

[0079] Determine the temperature error caused by the natural heat effect, and correct the surface temperature value according to the temperature error.

[0080] Among them, the temperature error is obtained by calculation, and the calculation formula is as follows:

[0081] Δt=KI 2 R;

[0082] In the formula, Δt is the temperature error, K is the coefficient, I is the current passing through the resistance temperature sensor when detecting the surface temperature value, and R is the resistance value of the resistance temperature sensor when detecting the surface temperature value.

[0083] Among them, the coefficient K is determined by considering the external environment of the blank holder stamping and the sensor installation and connection structure factors. In this embodiment, it is determined by the following method:

[0084] Measure the current I1 passing through the resistance temperature sensor and the resistance R1 of the resistance temperature sensor when the die is first stamped;

[0085] Increase the current passing through the resistance temperature sensor, and measure the current I n passing through the resistance temperature sensor and the resistance R n;

[0086] The coefficients are calculated, and the calculation formula is as follows:

[0087]

[0088] In the formula, α is the temperature coefficient of the resistance temperature sensor.

[0089] By correcting the temperature error introduced by the self-heating effect, a more realistic measured temperature is obtained, further improving the accuracy of temperature control.

[0090] In summary, for the adaptive temperature control method of the drawing die described in this embodiment, through simulation analysis, it can accurately determine whether the die needs to be cooled during drawing. When cooling is not required, no cooling device is set, thereby improving the stamping efficiency and reducing the stamping cost. When cooling is required, a cooling device is set, which can avoid the quality impact caused by high temperature on the drawing of the die, improve the quality of the die, and further improve the stamping efficiency. By setting a cooling device in the corresponding area of the die, targeted cooling of the high-temperature area of the die can be achieved, improving the accuracy of temperature control. By setting a resistance temperature sensor to collect the surface temperature value of the corresponding area of the die and starting the cooling device of the corresponding area only when the surface temperature value reaches the critical temperature value, not only can the energy consumption caused by the cooling device always being in the startup state be avoided, but also the quality defects of the die caused by not starting the cooling device can be avoided, improving the accuracy of temperature control. By correcting the error of the detected temperature, the accuracy of temperature measurement is further improved.

Claims

1. Adaptive temperature control method for a drawing die, characterized in that Including the following steps: Step 1: Determine the die material and the stamping parameters during the drawing forming of the die. The stamping parameters at least include: stamping load, stamping speed, blank holding force, and friction coefficient; Step 2: Construct a finite element model of the die drawing forming in 3D software. Based on the die material and stamping parameters and the finite element model, conduct a simulation analysis to determine the first surface temperature change ratio and its corresponding first material flow-in change ratio at each point during the die drawing forming; Step 3: Fit the function relationship between the material flow-in change ratio and the surface temperature change ratio according to the first surface temperature change ratio and its corresponding first material flow-in change ratio at each point; Step 4: Determine the second surface temperature change ratio corresponding to the maximum surface temperature value during the simulation analysis. Based on the second surface temperature change ratio and the function relationship, determine the corresponding second material flow-in change ratio; Step 5: Determine whether the die needs to be cooled during the drawing forming according to the second material flow-in change ratio. If so, set up a cooling device and cool the die through the cooling device during the drawing forming.

2. The adaptive temperature control method for the drawing die according to claim 1, characterized in that, Determining whether the die needs to be cooled during the drawing forming according to the second material flow-in change ratio specifically includes: Judging whether the second material flow-in change ratio is within a first preset range. If so, it is determined that the die needs to be cooled during the drawing forming. Otherwise, it is determined that the die does not need to be cooled during the drawing forming.

3. The adaptive temperature control method for the drawing die according to claim 2, wherein The setting of the cooling device specifically includes: When the second material flow-in change amount is within the first preset range, judge whether the second material flow-in change amount is within a second preset range. If so, set up a medium-low speed cooling device. Otherwise, set up a high-speed cooling device.

4. The adaptive temperature control method for the drawing die according to claim 1, characterized in that, The method further includes: Divide multiple regions on the die, respectively determine the maximum temperature value corresponding to each region during the simulation analysis, and for the maximum temperature value corresponding to each region, respectively determine its corresponding second material flow-in change ratio; Judge whether each region of the die needs to be cooled during the drawing forming according to the corresponding second material flow-in change ratio. If so, set up a cooling device in the corresponding region and cool the corresponding region of the die through the cooling device during the drawing forming.

5. The adaptive temperature control method for the drawing die according to claim 4, characterized in that The method further includes: When the cooling device is set up, obtain the critical temperature value affecting the die performance; When the die is being drawn and formed, real-time detect the surface temperature value of the region where the cooling device is set on the die. When the surface temperature value is greater than or equal to the critical temperature value, start the corresponding cooling device for cooling. When the surface temperature value is less than the critical temperature value, turn off the corresponding cooling device.

6. The adaptive temperature control method for the drawing die according to claim 5, characterized in that, The method for obtaining the critical temperature value includes: Preset the critical temperature value; or Calculate the temperature change ratio affecting the die performance according to the preset material flow-in change ratio and the function relationship, and determine the corresponding critical temperature value according to the temperature change ratio.

7. The adaptive temperature control method for the drawing die according to claim 5, characterized in that After real-time detecting the surface temperature value of the region where the cooling device is set on the die, it further includes: Determine the temperature error caused by the natural heat effect, and correct the surface temperature value according to the temperature error.

8. The adaptive temperature control method for the drawing die according to claim 7, wherein The surface temperature of the area where the cooling device is provided on the mold is detected in real time through a resistance temperature sensor, and the temperature error is obtained by calculation. The calculation formula is as follows: ； Wherein, is the temperature error, is the coefficient, is the current passing through the resistance temperature sensor when detecting the surface temperature value, is the resistance value of the resistance temperature sensor when detecting the surface temperature value.

9. The adaptive temperature control method for the drawing die according to claim 8, characterized in that, The coefficient is determined by the following method: Measure the current passing through the resistance temperature sensor in the first stamping of the die and the resistance of the resistance temperature sensor ; Increase the current passing through the resistance temperature sensor and measure the current passing through the resistance temperature sensor after the mold has been stamped a preset number of times and the resistance of the resistance temperature sensor ; The coefficient is calculated, and the calculation formula is as follows: ； In the formula, is the temperature coefficient of the resistance temperature sensor.

10. The adaptive temperature control method for the drawing die according to any one of claims 1 to 9, characterized in that, The cooling device at least includes: a gas source, a cooling pipeline, and a cooling cylinder assembly. The gas source is connected to the cooling cylinder assembly through the cooling pipeline, and the cooling pipeline is embedded inside the mold or in a groove opened on the back of the mold.

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