Temperature control method for die-casting die for metal casting

Abstract

The invention discloses a die-casting die temperature control method for metal casting, relates to the field of metal processing, and solves the problem of low die-casting success rate, and the method comprises the following steps: obtaining a material type and a raw material weight corresponding to a pre-input die-casting raw material, and calculating estimated melting heat of the die-casting raw material according to the raw material type and the raw material number; the melting temperature and the melting duration of the die-casting raw material are set according to the estimated melting heat, melting and refining are conducted on the basis of the melting temperature and the melting duration, and the slag-removed molten die-casting raw material is obtained; a release agent is sprayed to the inner surface of the die-casting cavity, then the slag-removed molten die-casting raw material is injected into the die-casting cavity, and the die-casting cavity is monitored in real time; according to the positive temperature abnormal deviation values and the negative temperature abnormal deviation values of the plurality of temperature monitoring subareas of the die-casting cavity, performing temperature correction regulation and control on the die-casting cavity; after the die-casting cavity is cooled, the die-casting device in the die-casting cavity is taken out; according to the invention, the die-casting success rate is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal processing, and specifically relates to a temperature control method for a die-casting mold used in metal casting. Background Art

[0002] Die casting is a metal casting process, which is characterized by applying high pressure to the molten metal using the inner cavity of the mold. The mold is usually processed from an alloy with higher strength, and this process is somewhat similar to injection molding; most die-cast castings are non-ferrous, such as zinc, copper, aluminum, magnesium, lead, tin, and lead-tin alloys and their alloys; a die-casting mold is a tool for casting metal parts and is used to complete the die-casting process on a dedicated die-casting forging machine. Depending on the type of die casting, a cold chamber die-casting machine or a hot chamber die-casting machine needs to be used; and appropriate temperature control can ensure the fluidity of the molten metal and reduce internal defects in the casting, such as shrinkage cavities, gas holes, etc.

[0003] However, at the present stage, when controlling the temperature of the die-casting mold, the temperature of the die-casting mold is usually monitored only in the final die-casting stage, resulting in a lower purity of the die-cast appliance after forming; at the same time, the existing monitoring methods usually select a small number of temperature monitoring points for monitoring, and there is a situation of missing abnormal temperatures, resulting in a reduction in the die-casting success rate; Therefore, the present invention proposes a temperature control method for a die-casting mold used in metal casting. Summary of the Invention

[0004] The purpose of the present invention is to propose a temperature control method for a die-casting mold used in metal casting to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A temperature control method for a die-casting mold used in metal casting, the method includes: Step S1, obtaining the material type and raw material weight corresponding to the pre-input die-casting raw material, and calculating the estimated melting heat of the die-casting raw material based on the raw material type and quantity; Step S2, setting the melting temperature and melting duration of the die-casting raw material according to the estimated melting heat, and performing melting and refining based on the melting temperature and melting duration to obtain a slag-removed molten die-casting raw material; Step S3, spraying a mold release agent on the inner surface of the die-casting cavity, and then injecting the slag-removed molten die-casting raw material into the die-casting cavity, and performing real-time monitoring on the die-casting cavity; Step S4, performing temperature correction control on the die-casting cavity according to the positive temperature abnormal deviation value and negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity; Step S5, after the die-casting cavity cools down, taking out the die-cast device inside the die-casting cavity.

[0006] Furthermore, the calculation process of the estimated melting heat is as follows: Step S11: Identify the melting point temperature WD of the die-casting raw material according to the material type 原 and the specific heat capacity C of the raw material 原 ; Step S12: Read the temperature of the die-casting mold at the initial moment and denote it as WD 压 ; Step S13: Calculate the estimated melting heat YR of the die-casting raw material through the formula 原 , and the specific formula is as follows: YR 原 =ZL 原 ×C 原 ×(WD 原 - WD 压 ) + QR 原 ; where ZL 原 is the weight of the raw material, and QR 原 is the latent heat of the die-casting raw material.

[0007] Furthermore, step S2 includes the following sub-steps: Step S21: Scan the outer surface image of the die-casting raw material, and automatically calculate the total outer surface area MJ of the die-casting raw material according to the modeling software; Step S22: Denote the distance from the geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and select the longest calibration distance as the maximum heating distance JL of the die-casting raw material; Step S23: Calculate the heat flux RLL of the die-casting raw material through Fourier's law of heat conduction, and the specific calculation formula is as follows: ; In the formula, K is the thermal conductivity of the die-casting raw material, and the negative sign in front of the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction; Step S24: Obtain the estimated heating duration by dividing the estimated melting heat of the die-casting raw material by the heat flux of the die-casting raw material.

[0008] Furthermore, step S2 also includes the following sub-steps: Step S25: Place the die-casting raw material in the metal melting bin, denote the melting point temperature as the melting temperature, and denote the estimated heating duration as the melting duration, and process the die-casting raw material based on the melting temperature and melting duration to obtain the molten die-casting raw material; Step S26: Add a refining agent to the molten die-casting raw material, adsorb the oxide impurities in the molten die-casting raw material through a chemical reaction, and precipitate the raw material residue; Step S27: Add a covering agent to the molten die-casting raw material, let it stand for a fixed duration, remove the dross on the surface of the molten die-casting raw material using a skimming tool, and repeat the operation until a constant weight is achieved. Step S28: Place the dross-removed molten die-casting raw material back into the metal melting chamber and heat it until it is completely melted to obtain the dross-removed molten die-casting raw material.

[0009] Furthermore, the step S3 includes the following sub-steps: Step S31: Obtain the volume TJ of the die-casting cavity 腔 , the volume TJ of the overflow groove 流 and the volume TJ of the exhaust groove 气 ; Step S32: Calculate the calculated injection volume TJ of the die-casting cavity through a formula 注 , and the specific formula is as follows: TJ 注 = (TJ 腔 + TJ 流 + TJ 气 ) × (1 + α) × (1 + β); where α is the shrinkage compensation coefficient and β is the process loss coefficient. Step S33: Calculate the calculated injection weight ZL of the die-casting cavity through a formula 注 , and the specific formula is as follows: ZL 注 = ρ 熔 × TJ 注 ; where ρ 熔 is the density of the die-casting raw material in the molten state.

[0010] Furthermore, the step S3 also includes the following sub-steps: Step S34: Inject the dross-removed molten die-casting raw material with a weight equal to the calculated injection weight into the pressure chamber, adjust the pressure in the pressure chamber to a negative pressure (≤ 10 mbar) to cause the gas in the pressure chamber to escape; connect the vacuum pump to the exhaust groove, reduce the pressure in the die-casting cavity to 10 mbar through the vacuum pump, and then connect the pressure chamber to the die-casting cavity. Step S35: Increase the pressure in the pressure chamber. Under the action of high pressure, the dross-removed molten die-casting raw material is injected into the die-casting cavity through multiple ingates. Step S36: Calculate the working die-casting temperature of the die-casting cavity. Step S37: The die-casting cavity performs die-casting operations at the working die-casting temperature, and monitors the temperature abnormal deviation value of the die-casting cavity.

[0011] Furthermore, the calculation process of the working die-casting temperature is specifically as follows: Step S361: Collect historical die-casting data of the same material type as the die-casting raw material. The historical die-casting data includes historical die-casting temperature, the total number of die-castings corresponding to the historical die-casting temperature, and the number of die-casting failures. Step S362: Divide the difference between the total number of die-castings and the number of die-casting failures by the total number of die-castings to obtain the die-casting success rate corresponding to different historical die-casting temperatures. Arrange the historical die-casting temperatures in descending order according to the die-casting success rate. Step S363: Select the top three historical die-casting temperatures, add them up, and take the average as the working die-casting temperature of the die-casting cavity.

[0012] Further, the monitoring process of the temperature anomaly deviation value is as follows: Step S371: Use an infrared sensing device to read the infrared image of the die-casting cavity during die-casting operations. Set multiple temperature monitoring points in the infrared image of the die-casting cavity at a fixed division interval. The number of each temperature monitoring point is n, and the upper limit value of n is x. Step S372: Centered on the temperature monitoring points, and with half of the multiple division intervals as the side length, divide the infrared image into multiple temperature monitoring sub-regions. The number of each temperature monitoring sub-region is the same as the number of the corresponding temperature monitoring point. Step S373: For any one temperature monitoring sub-region, read the pixel values of all pixel points in the temperature sub-region, and divide the pixel value of each pixel point into an R value component Ri, a G value component Gi, and a B value component Bi. Where i is the number of the pixel point, i = 1, 2, ……, z, and z is the upper limit value of the number. Step S374: Calculate the pixel comparison value XBi of each pixel point through the formula. The formula is as follows: XBi = Ri × A1 + Gi × A2 + Bi × A3; where A1, A2, and A3 are weight coefficients, and A2 > A1 > A3.

[0013] Further, the monitoring process of the temperature anomaly deviation value also includes: Step S375: Add up the pixel comparison values of all pixel points in the same temperature monitoring sub-region to obtain the pixel comparison mean value. Then calculate the pixel comparison standard deviation of the same temperature monitoring sub-region. Step S376: Take the pixel comparison mean value minus the pixel comparison standard deviation as the left endpoint of the interval, and take the pixel comparison mean value plus the pixel comparison standard deviation as the right endpoint of the interval. Construct a screening interval based on the left endpoint and the right endpoint of the interval. Traverse the pixel comparison values of all pixel points, and compare the pixel comparison values with the screening interval. If the pixel ratio value of a pixel point is less than the left endpoint of the interval or greater than the right endpoint of the interval, that is, the pixel ratio value is outside the screening interval, the corresponding pixel point is recorded as an abnormal temperature pixel point; If the pixel ratio value of a pixel point is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel ratio value is within the screening interval, no operation is performed; Step S377, record the pixel ratio values of all abnormal temperature pixel points, and obtain the comparison deviation value of the corresponding abnormal temperature pixel point by subtracting the pixel ratio mean value from the pixel ratio value; sum up all the comparison deviation values greater than zero in the same temperature monitoring sub-region to obtain the positive temperature abnormal deviation value of the corresponding temperature monitoring sub-region, and sum up all the comparison deviation values less than zero in the same temperature monitoring sub-region to obtain the negative temperature abnormal deviation value of the corresponding temperature monitoring sub-region; Step S378, calculate the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of all temperature sub-regions.

[0014] Furthermore, the step S4 includes the following sub-steps: Step S41, obtain the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of the temperature monitoring sub-region; Step S42, perform a cooling correction control on the abnormal temperature pixel points corresponding to the positive temperature abnormal deviation value in the temperature monitoring sub-region, that is, reduce the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature; Step S43, perform a heating correction control on the abnormal temperature pixel points corresponding to the negative temperature abnormal deviation value in the temperature monitoring sub-region, that is, increase the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature.

[0015] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are: 1. The present invention first obtains the material type and raw material weight of the pre-input die-casting raw material, calculates the estimated melting heat of the die-casting raw material according to the raw material type and quantity; then sets the melting temperature and melting duration of the die-casting raw material based on the estimated melting heat, and performs melting and refining based on the melting temperature and melting duration to obtain the slag-removed molten die-casting raw material; the present invention realizes the melting and refining of the die-casting raw material; 2. The present invention sprays a release agent on the inner surface of the die-casting cavity, then injects the slag-removed molten die-casting raw material into the die-casting cavity, monitors the die-casting cavity in real time, and then performs temperature correction control on the die-casting cavity according to the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity. After the die-casting cavity cools down, the die-casting device inside the die-casting cavity is taken out. The present invention improves the forming probability of the die-casting device by controlling the temperature of the die-casting mold. Description of the Drawings

[0016] For the convenience of those skilled in the art to understand, the present invention will be further described below with reference to the accompanying drawings.

[0017] Figure 1 It is the overall method flow chart of the present invention; Figure 2 It is the structural block diagram of the die-casting mold in the present invention; Figure 3 It is the structural schematic diagram of the computer device designed by the invention. Specific embodiments

[0018] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] Example 1, please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a method for controlling the temperature of a die-casting mold for metal casting. This method analyzes the raw material state of the raw materials corresponding to the device to be die-cast under different die-casting processes, and adjusts the temperature of different regions of the die-casting mold according to the raw material state, realizing precise control of the temperature of the die-casting mold during operation, and ensuring the forming of the device to be die-cast; As Figure 2 shown, the die-casting mold includes a metal melting bin, a pressure chamber, and a die-casting cavity; among them, the metal melting bin is used to convert the die-casting raw materials into a liquid molten state, the pressure chamber is used to adjust the pressure, and the die-casting cavity is used for actual die-casting operations; In this embodiment, the method for controlling the temperature of the die-casting mold is specifically as follows: Step S1, obtain the material type and raw material weight corresponding to the pre-input die-casting raw materials, and calculate the estimated melting heat of the die-casting raw materials based on the material type and the quantity of raw materials; In the present invention, the step S1 includes the following sub-steps: Step S11, identify the melting point temperature WD of the die-casting raw materials according to the material type 原 and the specific heat capacity C of the raw materials 原 ; Step S12, read the temperature of the die-casting mold at the corresponding initial moment and record it as WD 压 ; Step S13, calculate the estimated melting heat YR of the die-casting raw materials through the formula 原 , and the specific formula is as follows: YR 原 =ZL 原×C 原 × (WD 原 - WD 压 ) + QR 原 ; where ZL 原 is the weight of the raw material, and QR 原 is the latent heat of the die-casting raw material. The latent heat is the heat absorbed or released when a substance changes from one phase to another under isothermal and isobaric conditions. The specific calculation formula is as follows: The latent heat of the die-casting raw material = the weight of the raw material × the specific latent heat value of the die-casting raw material.

[0020] Step S2: Set the melting temperature and melting duration of the die-casting raw material according to the estimated melting heat, and perform melting and refining based on the melting temperature and melting duration to obtain slag-removed molten die-casting raw material; In the present invention, the step S2 includes the following sub-steps; Step S21: Scan the outer surface image of the die-casting raw material, and automatically calculate the total outer surface area MJ of the die-casting raw material according to the modeling software (such as SolidWorks or AutoCAD); Step S22: Denote the distance from the geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and select the longest calibration distance as the maximum heating distance JL of the die-casting raw material; Step S23: Calculate the heat flux RLL of the die-casting raw material through Fourier's law of heat conduction. The specific calculation formula is as follows: ; In the formula, K is the thermal conductivity of the die-casting raw material. It should be noted that the negative sign in front of the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction; Step S24: Obtain the estimated heating duration by dividing the estimated melting heat of the die-casting raw material by the heat flux of the die-casting raw material; Step S25: Place the die-casting raw material in the metal melting bin, denote the raw material melting point temperature as the melting temperature, and denote the estimated heating duration as the melting duration, and process the die-casting raw material based on the melting temperature and melting duration to obtain molten die-casting raw material; Step S26: Add a refining agent to the molten die-casting raw material, and adsorb the oxide impurities in the molten die-casting raw material through a chemical reaction to precipitate raw material residues; among them, the refining agent is a chloride, preferably a one-to-one mixture of sodium chloride and potassium chloride; Step S27: Add a covering agent to the molten die-casting raw material, let it stand for a fixed duration, and remove the floating slag on the surface of the molten die-casting raw material through a skimming tool, and repeat the operation until a constant weight is obtained; in actual operation, the fixed duration of standing is selected according to the material type of the die-casting raw material; for example, if the die-casting raw material is aluminum liquid or magnesium alloy, the fixed duration is ten to fifteen minutes; if the die-casting raw material is steel liquid, the fixed duration is five to ten minutes; Among them, the covering agent is a fluoride salt, and its purpose is to prevent the molten die-casting raw materials from oxidizing; for example, if the molten die-casting raw materials are aluminum, the covering agent is sodium hexafluoroaluminate; Step S28, place the molten die-casting raw materials after slag removal into the metal melting bin again and heat until completely melted to obtain the molten die-casting raw materials after slag removal.

[0021] Step S3, spray a release agent on the inner surface of the die-casting cavity, and then inject the molten die-casting raw materials after slag removal into the die-casting cavity, and monitor the die-casting cavity in real time; Among them, the main function of the release agent is to form a lubricating film on the surface of the die-casting cavity, thereby reducing the adhesion between the die-casting cavity and the die-casting product, so that the die-casting product can be more smoothly removed from the die-casting cavity; In the present invention, step S3 includes the following sub-steps: Step S31, obtain the volume TJ corresponding to the die-casting cavity 腔 , the volume TJ of the overflow groove 流 and the volume TJ of the exhaust groove 气 ; It should be noted that if the volume of the overflow groove or the volume of the exhaust groove cannot be determined, the volume of the overflow groove is regarded as 5% - 10% of the corresponding volume of the die-casting cavity, and the volume of the exhaust groove is regarded as 0.5% - 2% of the corresponding volume of the die-casting cavity; Step S32, calculate the calculated injection volume TJ of the die-casting cavity through the formula 注 , and the specific formula is as follows: TJ 注 = (TJ 腔 + TJ 流 + TJ 气 ) × (1 + α) × (1 + β); in the formula, α is the shrinkage compensation coefficient, and β is the process loss coefficient; When the molten metal cools and solidifies, its volume will shrink, so compensation needs to be made according to the material shrinkage rate; for example, the shrinkage compensation coefficient of aluminum alloy is 0.5% - 0.7%, the shrinkage compensation coefficient of zinc alloy is 0.7% - 1.2%, and the shrinkage compensation coefficient of magnesium alloy is 1.0% - 1.5%; the process loss coefficient is determined by factors such as the material type of the raw materials, processing technology, processing equipment, and operation technology, and generally takes a value of 3% - 5%; Step S33, calculate the calculated injection weight ZL of the die-casting cavity through the formula 注 , and the specific formula is as follows: ZL 注 = ρ 熔 × TJ 注 ; in the formula, ρ 熔 is the density of the die-casting raw materials in the molten state; Step S34, inject the slag-removed molten die-casting raw material with a weight equal to the calculated injection weight into the pressure chamber, adjust the pressure in the pressure chamber to a negative pressure (≤10 mbar) to prompt the gas in the pressure chamber to escape; connect the vacuum pump to the exhaust groove, reduce the pressure in the die-casting cavity to 10 mbar through the vacuum pump, and then connect the pressure chamber to the die-casting cavity; Step S35, increase the pressure in the pressure chamber. Under the action of high pressure, the slag-removed molten die-casting raw material is injected into the die-casting cavity through multiple ingates; Step S36, calculate the working die-casting temperature of the die-casting cavity; Specifically, the calculation process of the working die-casting temperature in step S36 is as follows: Step S361, collect historical die-casting data of the same material type as the die-casting raw material; among them, the historical die-casting data is the historical die-casting temperature and the total number of die-castings and the number of die-casting failures corresponding to the historical die-casting temperature; Step S362, divide the difference between the total number of die-castings and the number of die-casting failures by the total number of die-castings to obtain the die-casting success rate corresponding to different historical die-casting temperatures; arrange the historical die-casting temperatures in descending order according to the die-casting success rate; Step S363, select the top three historical die-casting temperatures, add them up, sum them, and take the average value as the working die-casting temperature of the die-casting cavity; Step S37, the die-casting cavity performs die-casting operations at the working die-casting temperature, and monitors the temperature abnormal deviation value of the die-casting cavity; In the present invention, the monitoring process in step S37 is specifically as follows: Step S371, read the infrared image of the die-casting cavity during die-casting operations through an infrared sensing device; set multiple temperature monitoring points in the infrared image of the die-casting cavity at a fixed division interval, and the number of each temperature monitoring point is n, and the upper limit value of n is x; Step S372, with the temperature monitoring point as the center and half of the multiple division intervals as the side length, divide the infrared image into multiple temperature monitoring sub-regions, and the number of each temperature monitoring sub-region is the same as the number of the corresponding temperature monitoring point; Step S373, for any one temperature monitoring sub-region, read the pixel values of all pixel points in the temperature sub-region, and divide the pixel value of each pixel point into an R value component Ri, a G value component Gi, and a B value component Bi; where i is the number of the pixel point, i = 1, 2,..., z, and z is the upper limit value of the number; Step S374, calculate the pixel comparison value XBi of each pixel point through the formula, and the formula is specifically as follows: XBi = Ri × A1 + Gi × A2 + Bi × A3; where A1, A2, and A3 are weight coefficients, and A2 > A1 > A3. Specifically, when calculating, A1 = 0.299, A2 = 0.587, and A3 = 0.114 can be selected. Step S375: Add up the pixel comparison values of all pixel points in the same temperature monitoring sub-region to obtain the pixel comparison mean value; then calculate the pixel comparison standard deviation of the same temperature monitoring sub-region. Step S376: Take the pixel comparison mean value minus the pixel comparison standard deviation as the left endpoint of the interval, and take the pixel comparison mean value plus the pixel comparison standard deviation as the right endpoint of the interval; construct a screening interval based on the left endpoint and the right endpoint of the interval. Traverse the pixel comparison values of all pixel points, and compare the pixel comparison values with the screening interval. If the pixel comparison value of a pixel point is less than the left endpoint of the interval or greater than the right endpoint of the interval, that is, the pixel comparison value is outside the screening interval, then mark the corresponding pixel point as an abnormal temperature pixel point. If the pixel comparison value of a pixel point is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel comparison value is within the screening interval, then no operation is performed. Step S377: Record the pixel comparison values of all abnormal temperature pixel points, and obtain the comparison deviation value of the corresponding abnormal temperature pixel point by subtracting the pixel comparison mean value from the pixel comparison value; add up all the comparison deviation values greater than zero in the same temperature monitoring sub-region to obtain the positive temperature abnormal deviation value of the corresponding temperature monitoring sub-region, and add up all the comparison deviation values less than zero in the same temperature monitoring sub-region to obtain the negative temperature abnormal deviation value of the corresponding temperature monitoring sub-region. Step S378: Calculate the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of all temperature sub-regions.

[0022] Step S4: Perform temperature correction and regulation on the die-casting cavity according to the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity. In the present invention, the step S4 includes the following sub-steps: Step S41: Obtain the positive temperature abnormal deviation value and the negative temperature abnormal deviation value of the temperature monitoring sub-region. Step S42: Perform a temperature reduction correction and regulation on the abnormal temperature pixel points corresponding to the positive temperature abnormal deviation value in the temperature monitoring sub-region, that is, reduce the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature. Step S43: Perform a temperature increase correction and regulation on the abnormal temperature pixel points corresponding to the negative temperature abnormal deviation value in the temperature monitoring sub-region, that is, increase the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature. Among them, the cooling correction control is achieved through a water temperature machine and a spot cooling machine; the heating correction control is achieved through an oil temperature machine; Step S5: After the die-casting cavity is cooled, take out the die-casting device inside the die-casting cavity; In this application, if there are corresponding calculation formulas, the above calculation formulas are all calculated by taking the numerical values without dimensions. For the coefficients such as weight coefficients and proportionality coefficients in the formulas, the magnitudes set are for obtaining a result value by quantifying each parameter. Regarding the magnitudes of the weight coefficients and proportionality coefficients, as long as the proportional relationship between the parameters and the result value is not affected.

[0023] Embodiment 2, as Figure 3 shown, this embodiment provides a computer device, which may include: a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete communication with each other through the communication bus. The processor can call the logical instructions in the memory to execute a die-casting mold temperature control method for metal casting, and the method includes: obtaining the material type and raw material weight corresponding to the pre-input die-casting raw material, calculating the estimated melting heat of the die-casting raw material according to the raw material type and quantity; setting the melting temperature and melting duration of the die-casting raw material according to the estimated melting heat, and performing melting and refining based on the melting temperature and melting duration to obtain slag-removed molten die-casting raw material; spraying a mold release agent on the inner surface of the die-casting cavity, and then injecting the slag-removed molten die-casting raw material into the die-casting cavity, and performing real-time monitoring on the die-casting cavity; performing temperature correction control on the die-casting cavity according to the positive temperature abnormal deviation value and negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity; after the die-casting cavity is cooled, taking out the die-casting device inside the die-casting cavity.

[0024] In addition, when the logical instructions in the above-mentioned memory are implemented in the form of software function units and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0025] Embodiment 3: The present application further provides a computer program product. The computer program product includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute a die-casting mold temperature control method provided by each of the above methods. The method includes: obtaining the material type and raw material weight corresponding to the pre-input die-casting raw material, calculating the estimated melting heat of the die-casting raw material according to the raw material type and quantity; setting the melting temperature and melting duration of the die-casting raw material according to the estimated melting heat, and performing melting and refining based on the melting temperature and melting duration to obtain slag-removed molten die-casting raw material; spraying a mold release agent on the inner surface of the die-casting cavity, and then injecting the slag-removed molten die-casting raw material into the die-casting cavity, and performing real-time monitoring on the die-casting cavity; performing temperature correction and control on the die-casting cavity according to the positive temperature abnormal deviation value and negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity; after the die-casting cavity cools down, taking out the die-casting device inside the die-casting cavity.

[0026] Embodiment 4: The present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is implemented to execute a die-casting mold temperature control method provided by each of the above. The method includes: obtaining the material type and raw material weight corresponding to the pre-input die-casting raw material, calculating the estimated melting heat of the die-casting raw material according to the raw material type and quantity; setting the melting temperature and melting duration of the die-casting raw material according to the estimated melting heat, and performing melting and refining based on the melting temperature and melting duration to obtain slag-removed molten die-casting raw material; spraying a mold release agent on the inner surface of the die-casting cavity, and then injecting the slag-removed molten die-casting raw material into the die-casting cavity, and performing real-time monitoring on the die-casting cavity; performing temperature correction and control on the die-casting cavity according to the positive temperature abnormal deviation value and negative temperature abnormal deviation value of multiple temperature monitoring sub-regions of the die-casting cavity; after the die-casting cavity cools down, taking out the die-casting device inside the die-casting cavity.

[0027] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative labor.

[0028] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. Step S1, obtaining the material type and raw material weight corresponding to the pre-input die-casting raw material, and calculating the estimated melting heat of the die-casting raw material according to the raw material type and raw material quantity; Step S2, setting the melting temperature and melting time of the die-casting raw material according to the estimated melting heat, and performing melting and refining based on the melting temperature and melting time to obtain a slag-free molten die-casting raw material; Step S3, spraying a release agent onto the inner surface of the die-casting cavity, and then injecting the slag-removed molten die-casting raw material into the die-casting cavity, and monitoring the die-casting cavity in real time; Step S4, performing temperature correction and control on the die-casting cavity according to the positive temperature abnormality deviation values ​​and the negative temperature abnormality deviation values ​​of the plurality of temperature monitoring sub-areas of the die-casting cavity; Step S5, after the die-casting cavity is cooled, the die-casting components in the die-casting cavity are taken out.

2. A method for controlling the temperature of a die-casting mold for metal casting according to claim 1, characterized in that: The calculation process of the estimated melting heat is as follows: Step S11, identifying the raw material melting point temperature WD of the die-casting raw material according to the material type 原 Specific heat capacity C of raw materials 原 ; Step S12, read the temperature of the die casting mold at the initial time and record it as WD 压 ; Step S13, calculating the estimated melting heat YR of the die-casting raw material by the formula 原 , the formula is as follows: Y 原 =ZL 原 ×C 原 × (WD 原 -WD 压 )+QR 原 Among them, ZL 原 is the weight of raw materials, QR 原 It is the latent heat of die casting raw materials.

3. A method for controlling the temperature of a die-casting mold for metal casting according to claim 1, characterized in that: The step S2 includes the following sub-steps: Step S21, scanning the outer surface image of the die-casting raw material, and automatically calculating the outer surface total area MJ of the die-casting raw material according to the modeling software; Step S22, recording the distance from the corresponding geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and selecting the longest calibration distance as the maximum heating distance JL of the die-casting raw material; Step S23, the heat flow RLL of the die-casting raw material is calculated by Fourier's heat conduction law, and the calculation formula is as follows: ； In the formula, K is the thermal conductivity of the die-casting raw material, and the negative sign in front of the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction; Step S24, obtaining an estimated heating time by dividing the estimated melting heat of the die-casting raw material by the heat flow of the die-casting raw material.

4. A method for controlling the temperature of a die-casting mold for metal casting according to claim 3, characterized in that: The step S2 further comprises the following sub-steps: Step S25, placing the die-casting raw material in a metal melting bin, recording the melting point temperature of the raw material as the melting temperature, recording the estimated heating time as the melting time, and processing the die-casting raw material based on the melting temperature and the melting time to obtain molten die-casting raw material; Step S26, adding a refining agent to the molten die-casting raw material, adsorbing oxide impurities in the molten die-casting raw material through chemical reaction, and precipitating raw material residue; Step S27, adding a covering agent to the molten die-casting raw material, leaving it to stand for a fixed time, removing scum on the surface of the molten die-casting raw material by a slag skimming tool, and repeating the operation until a constant weight is reached; Step S28, placing the molten die-casting raw material after the slag is removed in a metal melting bin again for heating until it is completely melted, thereby obtaining the molten die-casting raw material after the slag is removed.

5. The method for controlling the temperature of a die-casting mold for metal casting according to claim 1, characterized in that: The step S3 includes the following sub-steps: Step S31, obtaining the volume TJ corresponding to the die casting cavity 腔 , the volume of the overflow tank TJ 流 And the volume of the exhaust slot TJ 气 ; Step S32, calculating the injection volume TJ of the die casting cavity by the formula 注 , the formula is as follows: TJ 注 =(TJ 腔 +TJ 流 +TJ 气 )×(1+α)×(1+β); where α is the shrinkage compensation coefficient and β is the process loss coefficient; Step S33, calculate the injection weight ZL of the die casting cavity by the formula 注 , the formula is as follows: ZL 注 =ρ 熔 ×TJ 注 ; In the formula, ρ 熔 It is the density of the die casting raw material in the molten state.

6. A method for controlling the temperature of a die-casting mold for metal casting according to claim 5, characterized in that: The step S3 also includes the following sub-steps: Step S34, injecting the slag-free molten die-casting raw material with a weight equal to the calculated injection weight into the pressure chamber, increasing the pressure in the pressure chamber to negative pressure (≤10 mbar) to cause the gas in the pressure chamber to escape; connecting the vacuum pump to the exhaust groove, reducing the pressure in the die-casting cavity to 10 mbar through the vacuum pump, and then connecting the pressure chamber to the die-casting cavity; Step S35, increasing the pressure in the pressure chamber, and under the action of high pressure, the slag-removed molten die-casting raw materials are injected into the die-casting cavity through multiple inner gates; Step S36, calculating the working die-casting temperature of the die-casting cavity; Step S37 , performing die casting operation on the die casting cavity at the working die casting temperature, and monitoring the temperature abnormality deviation value of the die casting cavity.

7. A method for controlling the temperature of a die-casting mold for metal casting according to claim 6, characterized in that: The calculation process of the working die casting temperature is as follows: Step S361, collecting historical die-casting data of the same material type as the die-casting raw material; wherein the historical die-casting data is the historical die-casting temperature and the total number of die-casting times and the number of die-casting failures corresponding to the historical die-casting temperature; Step S362, obtaining the die-casting success rates corresponding to different historical die-casting temperatures by subtracting the number of die-casting failures from the total number of die-casting times and dividing it by the total number of die-casting times; and arranging the historical die-casting temperatures in descending order of the die-casting success rates; Step S363, selecting the top three historical die-casting temperatures, adding them together and taking the average value as the working die-casting temperature of the die-casting cavity.

8. A method for controlling the temperature of a die-casting mold for metal casting according to claim 6, characterized in that: The monitoring process of the abnormal temperature deviation value is as follows: Step S371, reading an infrared image of the die-casting cavity during die-casting operation by an infrared sensing device; setting a plurality of temperature monitoring points at fixed intervals in the infrared image of the die-casting cavity, each temperature monitoring point being numbered n, and an upper limit value of n being x; Step S372, taking the temperature monitoring point as the center and half of the multiple division intervals as the side length, the infrared image is divided into multiple temperature monitoring sub-areas, and the number of each temperature monitoring sub-area is the same as the number of the corresponding temperature monitoring point; Step S373, for any temperature monitoring sub-region, read the pixel values ​​of all pixels in the temperature sub-region, and divide the pixel value of each pixel into an R value component Ri, a G value component Gi and a B value component Bi; wherein i is the number of the pixel, i=1, 2, ..., z, and z is the upper limit value of the number; Step S374, calculate the pixel comparison value XBi of each pixel point by using the formula, the specific formula is as follows: XBi=Ri×A1+Gi×A2+Bi×A3; where A1, A2 and A3 are weight coefficients, among which A2>A1>A3.

9. A method for controlling the temperature of a die-casting mold for metal casting according to claim 8, characterized in that: The monitoring process of the abnormal temperature deviation value also includes: Step S375, adding up the pixel comparison values ​​of all pixels in the same temperature monitoring sub-region to obtain a pixel comparison mean; and then calculating the pixel comparison standard deviation of the same temperature monitoring sub-region; Step S376, taking the pixel comparison mean minus the pixel comparison standard deviation as the interval left endpoint, taking the pixel comparison mean plus the pixel comparison standard deviation as the interval right endpoint; constructing a screening interval based on the interval left endpoint and the interval right endpoint; Traverse the pixel comparison values ​​of all pixels and compare the pixel comparison values ​​with the screening interval; If the pixel comparison value of a pixel point is less than the left end point of the interval or greater than the right end point of the interval, that is, the pixel comparison value is outside the screening interval, the corresponding pixel point is recorded as an abnormal temperature pixel point; If the pixel comparison value of the pixel point is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel comparison value is within the screening interval, no operation is performed; Step S377, record the pixel comparison values ​​of all abnormal temperature pixels, and obtain the comparison deviation value of the corresponding abnormal temperature pixel by subtracting the pixel comparison mean value from the pixel comparison value; add and sum all the comparison deviation values ​​greater than zero in the same temperature monitoring sub-area to obtain the positive temperature abnormal deviation value of the corresponding temperature monitoring sub-area, and add and sum all the comparison deviation values ​​less than zero in the same temperature monitoring sub-area to obtain the negative temperature abnormal deviation value of the corresponding temperature monitoring sub-area; Step S378, calculating the positive temperature anomaly deviation values ​​and the negative temperature anomaly deviation values ​​of all temperature sub-regions.

10. A method for controlling the temperature of a die-casting mold for metal casting according to claim 1, characterized in that: The step S4 includes the following sub-steps: Step S41, obtaining a positive temperature anomaly deviation value and a negative temperature anomaly deviation value of a temperature monitoring sub-area; Step S42, performing cooling correction control on the abnormal temperature pixel points corresponding to the positive temperature abnormal deviation values ​​in the temperature monitoring sub-area, that is, reducing the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature; Step S43, performing temperature increase correction control on the abnormal temperature pixel points corresponding to the negative temperature abnormal deviation values ​​in the temperature monitoring sub-area, that is, raising the real-time temperature of the abnormal temperature pixel points to the working die-casting temperature.

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