An intelligent control system for horizontal continuous casting machine of cast iron profiles

Abstract

The present invention relates to the technical field of crystallizer cooling control, and specifically to an intelligent control system for a horizontal continuous casting machine for cast iron profiles. The present invention first obtains the real-time production data of the horizontal continuous casting machine; further obtains the current billet cooling parameters and the current heat acceptance of the crystallizer; further obtains the heat accumulation coefficient of the current crystallizer according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat acceptance; further obtains the current heat residual coefficient according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range; finally, according to the current heat residual coefficient, adjusts the cooling intensity of the crystallizer. The present invention analyzes the heat residual situation of the crystallizer, and intelligently and dynamically adjusts the cooling intensity through the heat residual coefficient, thereby ensuring the one-time cooling of the billet, while avoiding the energy waste caused by excessive cooling, reducing the wear and aging of the crystallizer, and reducing the production cost of the enterprise.

Description

Technical Field

[0001] The invention relates to the technical field of crystallizer cooling control, and in particular to an intelligent control system for a horizontal continuous casting machine of cast iron profiles. Background Art

[0002] The working principle of the horizontal continuous casting machine is mainly based on the continuous casting technology, which is the process of continuously pouring, solidifying and forming molten metal into castings. It has the advantages of good stability and high dimensional accuracy. In the horizontal continuous casting machine, the crystallizer is one of the key components of the system.

[0003] During the cooling process of the crystallizer, if the cooling adopts a constant speed cooling mode, it will be affected by the pouring molten iron, the temperature of the water channel will continue to rise, the actual temperature of the subsequent water inlet will be high, and there will be residual heat in the crystallizer, which will affect the cooling effect, resulting in weaker shell formation of the ingot after the first cooling, and secondary cooling may cause cracks and other defects in the shell, affecting production quality and efficiency; if the flow rate of cooling water is over-emphasized, it will easily cause energy waste and increase the production cost of the enterprise; and the cooling structure of the crystallizer may gradually wear, resulting in a weakened cooling effect, which will also affect the treatment results of the first cooling and affect the production quality of the horizontal continuous casting machine. Summary of the invention

[0004] In order to solve the technical problem that unreasonable cooling control of the crystallizer causes heat accumulation in the crystallizer, resulting in quality defects of the cast billet, the purpose of the present invention is to provide an intelligent control system for a horizontal continuous casting machine of cast iron profiles. The technical scheme adopted is as follows:

[0005] An intelligent control system for a horizontal continuous casting machine for cast iron profiles, the system comprising:

[0006] Data acquisition module: used to obtain real-time production data of the horizontal continuous casting machine; the production data at least includes pouring temperature, billet surface temperature, working parameters of the crystallizer, specific heat capacity of the billet material and billet drawing parameters;

[0007] Cooling analysis module: used to obtain the current billet cooling parameter according to the difference between the current surface temperature of all billets and the pouring temperature, combined with the distance between the sampling point of each temperature data and the center of the billet; according to the current billet drawing parameters and the working parameters of the crystallizer, combined with the billet cooling parameters and the specific heat capacity of the billet material, obtain the heat acceptance degree of the current crystallizer; according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat acceptance degree, obtain the heat accumulation coefficient of the current crystallizer; according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range, obtain the current heat residual coefficient;

[0008] Intelligent control module: used to adjust the cooling intensity of the crystallizer according to the current heat residual coefficient.

[0009] Furthermore, the method for obtaining the cooling parameters of the casting blank includes:

[0010] According to the distance between each sampling point and the center of the ingot, a cooling weight of each sampling point is obtained; the distance between the sampling point and the center of the ingot is positively correlated with the cooling weight, and the sum of the cooling weights of all sampling points is 1;

[0011] According to the current surface temperature of the ingot at each sampling point, combined with the cooling weight of each sampling point, current weighted temperature data is obtained;

[0012] The difference between the current pouring temperature and the weighted temperature data is used as the current billet cooling parameter.

[0013] Furthermore, the method for obtaining the heat receiving degree includes:

[0014] The working parameters of the crystallizer at least include the length of the crystallizer, the flow rate of the cooling water, the water gap area and the inlet temperature of the cooling water; the drawing parameters at least include the rotation speed and operation time of the traction wheel; a drawing cycle includes one pulling and one pushing;

[0015] According to the casting parameters, a periodic displacement of a casting cycle is obtained; according to the length of the crystallizer and the periodic displacement, a transfer time parameter is obtained;

[0016] According to the transfer time parameter, the billet cooling parameter and the specific heat capacity of the billet material, a current heat transfer index is obtained; the billet cooling parameter and the specific heat capacity of the billet material are both positively correlated with the heat transfer index; the transfer time parameter is negatively correlated with the heat transfer index;

[0017] The heat acceptance degree of the current crystallizer is obtained according to the current cooling water flow rate, water inlet temperature, water seam area and the heat transfer index; the cooling water inlet temperature is negatively correlated with the heat acceptance degree; the cooling water flow rate, water seam area and the heat transfer index are all positively correlated with the heat acceptance degree.

[0018] Furthermore, the method for obtaining the periodic displacement includes:

[0019] The rotation speed of the traction machine in one casting cycle is integrated with the operation time, and the integrated value is used as the cycle displacement.

[0020] Furthermore, the method for obtaining the transfer time parameter includes:

[0021] The ratio of the length of the crystallizer to the periodic displacement is taken as the transfer time parameter.

[0022] Furthermore, the method for obtaining the heat accumulation coefficient includes:

[0023] The working parameters of the crystallizer also include the inlet and outlet temperatures of the cooling water; obtaining the temperature difference of the cooling water at the inlet and outlet of the crystallizer;

[0024] According to the temperature difference of the cooling water at the inlet and outlet, combined with the billet cooling parameters and the heat acceptance degree, the heat accumulation coefficient of the current crystallizer is obtained; the temperature difference of the cooling water at the inlet and outlet is negatively correlated with the heat accumulation coefficient; the billet cooling parameters and the heat acceptance degree are positively correlated with the heat accumulation coefficient.

[0025] Furthermore, the method for obtaining the heat residual coefficient includes:

[0026] The sum of all the accumulated heat coefficients in the current preset time domain neighborhood range is normalized to obtain the current heat residual coefficient.

[0027] Furthermore, the method for regulating the cooling intensity of the crystallizer according to the current heat residual coefficient includes:

[0028] Get the initial parameters of the PID controller;

[0029] Based on the current residual heat coefficient, the proportional coefficient in the initial parameter is adjusted to obtain a corrected proportional coefficient; and according to the current corrected proportional coefficient, the flow rate of the cooling water of the crystallizer is controlled.

[0030] Furthermore, the method for obtaining the initial parameters of the PID controller includes:

[0031] The initial parameters of the PID controller are obtained by the Ziegler–Nichols method.

[0032] Furthermore, the method for adjusting the proportional coefficient in the initial parameters based on the current residual heat coefficient includes:

[0033] The current residual heat coefficient plus a constant 1 is used as an amplification weight of the proportional coefficient, and the product of the amplification weight and the proportional coefficient is used as a correction proportional coefficient.

[0034] The present invention has the following beneficial effects:

[0035] The present invention first obtains the real-time production data of the horizontal continuous casting machine to provide a basis for subsequent analysis; further obtains the current billet cooling parameters to represent the temperature change characteristics of the current billet after cooling through the crystallizer, so as to prepare for the subsequent analysis of the energy transfer inside the crystallizer and the judgment of the heat residue in the crystallizer; further, according to the current billet drawing parameters and the working parameters of the crystallizer, combined with the billet cooling parameters and the specific heat capacity of the billet material, the heat reception degree of the current crystallizer is obtained to characterize the heat reception of the crystallizer during a cooling process, so as to prepare for the subsequent analysis of the heat accumulation of the crystallizer; further, according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat reception degree, the heat accumulation coefficient of the current crystallizer is obtained to represent the heat accumulation of the current crystallizer, so as to provide a basis for the cooling mode of the subsequent control system; further, according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range, the accumulation and dissipation process of the heat accumulation is better understood, and the current heat residue coefficient is obtained, so as to facilitate the subsequent dynamic adjustment of the cooling strategy to ensure that the heat is dissipated in time, avoid the influence of the heat accumulation in the crystallizer on the cooling effect, and ensure the production quality; finally, according to the current heat residue coefficient, the cooling intensity of the crystallizer is regulated. The present invention analyzes the residual heat situation of the crystallizer and intelligently and dynamically adjusts the cooling intensity through the residual heat coefficient, thereby ensuring one-time cooling of the ingot, avoiding energy waste caused by overcooling, reducing wear and aging of the crystallizer, and reducing the production cost of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 A system block diagram of an intelligent control system for a horizontal continuous casting machine for cast iron profiles provided by one embodiment of the present invention;

[0038] Figure 2 A schematic diagram of a horizontal continuous casting production line for cast iron profiles provided by one embodiment of the present invention;

[0039] Figure 3 A horizontal continuous casting production process flow chart provided by one embodiment of the present invention;

[0040] Figure 4 A schematic diagram of a crystallizer structure provided by an embodiment of the present invention;

[0041] Figure 5 A schematic diagram of a casting billet pulling process provided by one embodiment of the present invention;

[0042] Figure 6 A schematic diagram of a wheel throwing method curve provided for one embodiment of the present invention.

[0043] The numbers in the figure are: 1. Holding furnace; 2. Crystallizer; 3. Support roller; 4. Traction machine; 5. Cutting machine; 6. Back-pressure gantry; 7. Support roller; 8. Material receiving cylinder; 9. Press breaker; 10. Wire-out machine; 11. Cast iron profile. DETAILED DESCRIPTION

[0044] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation method, structure, features and effects of an intelligent control system for a horizontal continuous casting machine of cast iron profiles proposed by the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0045] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0046] The specific scheme of the intelligent control system for a horizontal continuous casting machine of cast iron profiles provided by the present invention is described in detail below with reference to the accompanying drawings.

[0047] See also Figure 1 , which shows a system block diagram of an intelligent control system for a horizontal continuous casting machine for cast iron profiles provided by an embodiment of the present invention. The system includes: a data acquisition module 101, a cooling analysis module 102 and an intelligent control module 103.

[0048] Data acquisition module 101: used to obtain real-time production data of the horizontal continuous casting machine; the production data at least includes pouring temperature, billet surface temperature, crystallizer working parameters, specific heat capacity of billet material and billet drawing parameters.

[0049] The production of cast iron profiles using a horizontal continuous caster involves several steps: see Figure 2, which shows a schematic diagram of a horizontal continuous casting production line for cast iron profiles provided by an embodiment of the present invention, which includes a holding furnace 1, a crystallizer 2, support rollers 3, a traction machine 4, a cutting machine 5, a back-pressure gantry 6, a support roller 7, a material receiving cylinder 8, a press breaker 9, a wire-out machine 10 and a cast iron profile 11. The molten iron flows from the holding furnace 1 into the crystallizer 2, and after solidification in the crystallizer 2, it is pulled out of the crystallizer 2 by the traction machine 4 to obtain a cast billet, which is then processed by the cutting machine 5, the back-pressure gantry 6 and the press breaker 9 to obtain a cast iron profile 11; the support rollers 3 and 7 are used to support the cast billet to prevent the cast billet from deformation, and the wire-out machine 10 is used to transport the cast iron profile 11.

[0050] See also Figure 3 , which shows a horizontal continuous casting production process flow chart provided by an embodiment of the present invention. After the alloy is melted, it is kept warm and sent to the crystallizer for cooling, and then the billet drawing speed and method are set, so the real-time production data of the horizontal continuous casting machine is first obtained; the production data includes at least the pouring temperature, the billet surface temperature, the working parameters of the crystallizer and the billet drawing parameters, which provide a basis for subsequent analysis.

[0051] See also Figure 4 , which shows a schematic diagram of a crystallizer structure provided by an embodiment of the present invention, including a spiral water channel, an iron sleeve and a graphite sleeve.

[0052] See also Figure 5 , which shows a schematic diagram of a billet pulling process provided by an embodiment of the present invention, wherein the AC servo motor drives the traction wheel, which cooperates with the upper pressure wheel to pull the billet out of the crystallizer.

[0053] It should be noted that the specific production process is determined by the product performance parameters and is not limited here. In one embodiment of the present invention, the width of the crystallizer water gap is The initial water flow rate is The initial cooling water inlet temperature is Celsius, production Square billet, mold length is , the data collection frequency is 1 second / time.

[0054] Cooling analysis module 102: used to obtain the current billet cooling parameters according to the difference between all current billet surface temperatures and the pouring temperature, combined with the distance between the sampling point of each temperature data and the center of the billet; obtain the current heat acceptance of the crystallizer according to the current billet drawing parameters and the working parameters of the crystallizer, combined with the billet cooling parameters and the specific heat capacity of the billet material; obtain the current heat accumulation coefficient of the crystallizer according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat acceptance; obtain the current heat residual coefficient according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range.

[0055] In order to analyze the cooling effect of the crystallizer and optimize the cooling control, we first analyze the difference between the current surface temperature of all ingots and the pouring temperature, combined with the distance between the sampling point of each temperature data and the center of the ingot, to obtain the current ingot cooling parameters, which represent the temperature change characteristics of the current ingot after cooling through the crystallizer, in preparation for the subsequent analysis of the energy transfer inside the crystallizer and the judgment of the heat residue in the crystallizer.

[0056] Preferably, in one embodiment of the present invention, considering that during the cooling process of the crystallizer, the cooling effects at different positions of the ingot are different, the contact distance between the edge of the ingot surface and the high-temperature molten iron in the center is relatively far, and compared with the center, the edge is less affected by the internal high-temperature molten iron, which can better reflect the cooling effect of the ingot in the crystallizer. Therefore, the cooling weight of each sampling point is obtained according to the distance between each sampling point and the center of the ingot; the distance between the sampling point and the center of the ingot is positively correlated with the cooling weight, and the sum of the cooling weights of all sampling points is 1.

[0057] As an example, the distances between all sampling points and the center of the billet are summed, and the ratio of the distance to the center of the billet corresponding to each sampling point to the sum of the distances to the centers of all billets is used as the cooling weight of each sampling point.

[0058] It should be noted that the sampling point is the temperature measurement point on the surface of the ingot, not the installation position of the temperature measuring equipment, and the center of the ingot is the centroid of the ingot cross section.

[0059] According to the current surface temperature of the ingot at each sampling point, combined with the cooling weight of each sampling point, the current weighted temperature data is obtained.

[0060] As an example, taking the cooling weight as the weighted weight, weighted summation is performed on the corresponding current surface temperature of the ingot at all sampling points to obtain the current weighted temperature data.

[0061] The difference between the current casting temperature and the weighted temperature data is used to represent the difference between the current surface temperature of all casting billets and the casting temperature, which is used as the current casting billet cooling parameter.

[0062] Taking into account the current casting parameters and the working parameter settings of the crystallizer, it will also affect the cooling effect of the ingot material; and different ingot materials have different thermal conductivity, and the amount of heat transferred to the crystallizer is different. Therefore, according to the current casting parameters and the working parameters of the crystallizer, combined with the ingot cooling parameters and the specific heat capacity of the ingot material, the heat reception of the current crystallizer is obtained to characterize the heat reception of the crystallizer during a cooling process, in preparation for the subsequent analysis of the heat accumulation of the crystallizer.

[0063] Preferably, in one embodiment of the present invention, the working parameters of the crystallizer at least include the length of the crystallizer, the flow rate of cooling water, the water gap area and the inlet temperature of cooling water; the casting parameters at least include the rotation speed and operation time of the traction wheel; in order to make the liquid metal fully and evenly crystallize in the crystallizer to ensure the quality of the casting, the casting process adopts a high-precision intermittent casting method, that is, the traction machine must complete accurate "pull-stop-push-stop" cycle control, please refer to Figure 6 , which shows a schematic diagram of a billet drawing method curve provided by an embodiment of the present invention, wherein the horizontal axis is time, the vertical axis is the rotation speed of the traction machine, pulling outward is the positive direction of the rotation speed, and one billet drawing cycle includes one pulling and one pushing.

[0064] Considering that the longer the billet pulled out from the crystallizer in a billet drawing cycle, the greater the periodic displacement of the billet, and the less time for heat transfer inside the crystallizer, the periodic displacement of a billet drawing cycle is obtained according to the billet drawing parameters; the transfer time parameters are obtained according to the length and periodic displacement of the crystallizer to characterize the heat transfer characteristics of the unit billet in the time dimension.

[0065] As an example, the rotation speed of the traction machine in one billet drawing cycle is integrated with the operation time, and the integrated value is used as the periodic displacement. The ratio of the length of the crystallizer to the periodic displacement is used as the transfer time parameter.

[0066] In other embodiments of the present invention, it is also considered that the longer the duration of a billet drawing cycle is, the longer the heat transfer time of the billet in the crystallizer is. Therefore, the transfer time parameter can be calculated in combination with the billet drawing cycle time of the billet drawing cycle. For example, the length of the crystallizer is multiplied by the billet drawing cycle time, and then the ratio is obtained by the periodic displacement as the transfer time parameter. A positive correlation function such as Or a negative correlation function such as Mapping is performed, where Expressed as a natural constant is the exponential function of the base, Represents the independent variable.

[0067] According to the transfer time parameters, the billet cooling parameters and the specific heat capacity of the billet material, the current heat transfer index is obtained to characterize the heat transfer characteristics per unit time; considering that the larger the billet cooling parameters, the greater the billet cooling amplitude, the larger the specific heat capacity of the billet material, and the greater the heat transferred by reducing the unit temperature of the unit mass of the billet, the billet cooling parameters and the specific heat capacity of the billet material are positively correlated with the heat transfer index; the transfer time parameters are negatively correlated with the heat transfer index.

[0068] As an example, the slab cooling parameter and the specific heat capacity of the slab material are multiplied, and the ratio of the product to the transfer time parameter is used as the heat transfer index.

[0069] Considering that the faster the current cooling water flow rate, the larger the water gap area, the lower the water inlet temperature, the stronger the ability of the crystallizer to receive heat, and the larger the heat transfer index, the stronger the ability of the ingot to transfer heat to the crystallizer. Therefore, according to the current cooling water flow rate, water inlet temperature, water gap area and heat transfer index, the heat receptivity of the current crystallizer is obtained to characterize the heat receptivity of the crystallizer; the cooling water inlet temperature is negatively correlated with the heat receptivity; the cooling water flow rate, water gap area and heat transfer index are all positively correlated with the heat receptivity.

[0070] As an example, the product of the current cooling water flow rate, the water seam area and the heat transfer index is used as the numerator, and the water inlet temperature is used as the denominator. After the fraction is normalized, it is used as the heat acceptance degree of the current crystallizer.

[0071] The normalization function can be function; it can also be the sensitivity adjusted Functions such as , where 0.2 is the sensitivity coefficient, is the independent variable, the smaller the sensitivity coefficient is, The smoother the function, the slower the rate of change, which avoids the mapping interval corresponding to the value interval of the independent variable being too small, which is not conducive to analyzing the differences between the independent variables.

[0072] It should be noted that the water seam area is related to the flow rate of cooling water, and the embodiment of the present invention mainly regulates the cooling intensity of the crystallizer by controlling the water flow rate, so the water flow rate is constantly changing dynamically, and therefore the water seam area is an instantaneous value. The calculation formula for the water seam area is already well known to those skilled in the art and will not be repeated here.

[0073] After obtaining the heat absorption degree of the crystallizer during the first cooling process, in order to analyze the influence of the residual heat of the internal components of the crystallizer on the subsequent cooling process, it is also necessary to obtain the heat accumulation coefficient of the current crystallizer according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat absorption degree, to indicate the current heat accumulation situation of the crystallizer and provide a basis for the cooling mode of the subsequent control system.

[0074] Preferably, in one embodiment of the present invention, considering that the smaller the temperature difference of the cooling water at the inlet and outlet of the crystallizer is, the less heat the cooling water takes away in the crystallizer; at the same time, the greater the heat acceptance and the billet cooling parameter is, the more heat the billet transfers in the crystallizer, the stronger the ability of the crystallizer to absorb heat is, the more likely the crystallizer is to accumulate heat, and the greater the heat accumulation coefficient is, based on this, the working parameters of the crystallizer also include the inlet temperature and outlet temperature of the cooling water; obtain the temperature difference of the cooling water at the inlet and outlet of the crystallizer;

[0075] According to the temperature difference of the cooling water at the inlet and outlet, combined with the billet cooling parameters and heat acceptance, the heat accumulation coefficient of the current crystallizer is obtained; the temperature difference of the cooling water at the inlet and outlet is negatively correlated with the heat accumulation coefficient; the billet cooling parameters and heat acceptance are positively correlated with the heat accumulation coefficient.

[0076] As an example, the product of the billet cooling parameter and the heat receiving degree is used as the numerator, the temperature difference of the cooling water at the inlet and outlet is used as the denominator, and the fraction is used as the current heat accumulation coefficient; the calculation formula of the heat accumulation coefficient includes: ;in Indicates the current heat accumulation coefficient; Indicates the current heat receiving degree of the crystallizer; Indicates the current temperature difference between the inlet and outlet of the crystallizer; It represents the current ingot cooling parameters. It should be noted that since the cooling water absorbs heat in the crystallizer and the temperature rises, the denominator must not be zero.

[0077] In the calculation formula of the heat accumulation coefficient, the smaller the temperature change of the cooling water in the crystallizer, that is, The smaller it is, the less heat is taken away by the cooling water, the easier it is for heat to accumulate in the crystallizer, and the larger the heat accumulation coefficient. The larger the value, the greater the temperature drop of the billet after passing through the crystallizer, and the more heat is released. The larger it is, the stronger the ability of the crystallizer to absorb heat is, the easier it is for heat to accumulate in the crystallizer, and the larger the heat accumulation coefficient is.

[0078] Considering that the heat accumulation in the crystallizer will gradually accumulate over time, and this heat accumulation effect will not disappear immediately, but will continue to affect the cooling process of the ingot for a certain period of time. By analyzing the distribution of the heat accumulation coefficient in the time domain, we can better understand the accumulation and dissipation process of heat accumulation. Therefore, according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range, the current heat residual coefficient is obtained, so that the cooling strategy can be dynamically adjusted in the future to ensure that the heat is dissipated in time, avoid the influence of heat accumulation in the crystallizer on the cooling effect, and ensure production quality.

[0079] Preferably, in one embodiment of the present invention, the sum of all the accumulated heat coefficients in the current preset time domain neighborhood range is normalized to obtain the current heat residual coefficient.

[0080] As an example, the preset time domain neighborhood range is 10 seconds long, with the current moment as the end point and the adjacent historical moment 10 seconds ago as the start point; normalization can also be used function.

[0081] In other embodiments of the present invention, weighted summation can also be used, and the summation result can be normalized to obtain the heat residual coefficient, wherein the weighted weight is negatively correlated with the time interval of the current moment, the closer to the current moment, the larger the weighted weight, and the sum of all weighted weights is 1.

[0082] Intelligent control module 103: used to adjust the cooling intensity of the crystallizer according to the current heat residual coefficient.

[0083] After obtaining the heat residual characteristics of the current crystallizer, the cooling intensity of the crystallizer can be adjusted according to the heat residual situation.

[0084] Preferably, in one embodiment of the present invention, considering that the flow rate of cooling water is easier to control and has lower cost, the flow rate of cooling water in the crystallizer is adjusted by a PID controller to control the cooling intensity of the crystallizer, and based on this, the initial parameters of the PID controller are obtained;

[0085] Based on the current heat residual coefficient, the proportional coefficient in the initial parameters is adjusted to obtain the corrected proportional coefficient; according to the current corrected proportional coefficient, the flow rate of the cooling water of the crystallizer is controlled.

[0086] Preferably, in one embodiment of the present invention, the initial parameters of the PID controller are obtained by the Ziegler-Nichols method.

[0087] It should be noted that the Ziegler-Nichols method and the PID control method are already well-known technical means to those skilled in the art, and will not be described in detail here.

[0088] Preferably, in one embodiment of the present invention, considering that with the production of castings, the inlet temperature of the circulating cooling water will usually increase and a larger water flow rate is required, the current heat residual coefficient is added with a constant 1 as the amplification weight of the proportional coefficient, and the product of the amplification weight and the proportional coefficient is used as the corrected proportional coefficient.

[0089] The calculation formula for the correction proportionality factor includes: ;in Indicates the current heat residual coefficient; represents the amplification weight, represents the proportionality coefficient; Represents the correction proportional coefficient. In the formula, the heat residual coefficient The larger it is, the more serious the heat accumulation in the crystallizer is, and the more it is necessary to increase the water flow rate in the crystallizer to further improve the cooling effect of the crystallizer and ensure production quality.

[0090] In other embodiments of the present invention, the implementer may also add an adjustment coefficient to control the regulation range of the water flow rate. For example, the adjustment coefficient is 0.5. The water flow rate control range is from the initial flow rate to 1.5 times the initial flow rate.

[0091] In summary, in order to solve the technical problem that unreasonable cooling control of the crystallizer causes heat accumulation in the crystallizer and leads to quality defects in the billet, the present invention provides an intelligent control system for a horizontal continuous casting machine for cast iron profiles. The present invention first obtains the real-time production data of the horizontal continuous casting machine; further obtains the current billet cooling parameters; further obtains the heat acceptance of the current crystallizer according to the current billet drawing parameters and the working parameters of the crystallizer, combined with the billet cooling parameters and the specific heat capacity of the billet material; further obtains the heat accumulation coefficient of the current crystallizer according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat acceptance; further obtains the current heat residual coefficient according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range; finally, according to the current heat residual coefficient, adjusts the cooling intensity of the crystallizer. The present invention analyzes the heat residual situation of the crystallizer, and intelligently and dynamically adjusts the cooling intensity through the heat residual coefficient, thereby ensuring the one-time cooling of the billet, while avoiding the energy waste caused by excessive cooling, reducing the wear and aging of the crystallizer, and reducing the production cost of the enterprise.

[0092] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0093] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. An intelligent control system for a horizontal continuous casting machine for cast iron profiles, characterized in that: The system comprises: Data acquisition module: used to obtain real-time production data of the horizontal continuous casting machine; the production data at least includes pouring temperature, billet surface temperature, working parameters of the crystallizer, specific heat capacity of the billet material and billet drawing parameters; Cooling analysis module: used to obtain the current billet cooling parameter according to the difference between the current surface temperature of all billets and the pouring temperature, combined with the distance between the sampling point of each temperature data and the center of the billet; according to the current billet drawing parameters and the working parameters of the crystallizer, combined with the billet cooling parameters and the specific heat capacity of the billet material, obtain the heat acceptance degree of the current crystallizer; according to the temperature change of the cooling water in the crystallizer, combined with the billet cooling parameters and the heat acceptance degree, obtain the heat accumulation coefficient of the current crystallizer; according to the distribution characteristics of the heat accumulation coefficient in the current preset time domain neighborhood range, obtain the current heat residual coefficient; Intelligent control module: used to adjust the cooling intensity of the crystallizer according to the current heat residual coefficient; The method for obtaining the billet cooling parameters comprises: According to the distance between each sampling point and the center of the ingot, a cooling weight of each sampling point is obtained; the distance between the sampling point and the center of the ingot is positively correlated with the cooling weight, and the sum of the cooling weights of all sampling points is 1; According to the current surface temperature of the ingot at each sampling point, combined with the cooling weight of each sampling point, current weighted temperature data is obtained; The difference between the current pouring temperature and the weighted temperature data is used as the current casting billet cooling parameter; The method for obtaining the heat receiving degree includes: The working parameters of the crystallizer at least include the length of the crystallizer, the flow rate of the cooling water, the water gap area and the inlet temperature of the cooling water; the drawing parameters at least include the rotation speed and operation time of the traction wheel; a drawing cycle includes one pulling and one pushing; According to the casting parameters, a periodic displacement of a casting cycle is obtained; according to the length of the crystallizer and the periodic displacement, a transfer time parameter is obtained; According to the transfer time parameter, the billet cooling parameter and the specific heat capacity of the billet material, a current heat transfer index is obtained; the billet cooling parameter and the specific heat capacity of the billet material are both positively correlated with the heat transfer index; the transfer time parameter is negatively correlated with the heat transfer index; According to the current cooling water flow rate, water inlet temperature, water seam area and the heat transfer index, the heat acceptance degree of the current crystallizer is obtained; the cooling water inlet temperature is negatively correlated with the heat acceptance degree; the cooling water flow rate, water seam area and the heat transfer index are all positively correlated with the heat acceptance degree; The product of the current cooling water flow rate, the water seam area and the heat transfer index is used as the numerator, and the water inlet temperature is used as the denominator. After normalization, the fraction is used as the heat acceptance degree of the current crystallizer; The method for obtaining the heat accumulation coefficient includes: The working parameters of the crystallizer also include the inlet and outlet temperatures of the cooling water; obtaining the temperature difference of the cooling water at the inlet and outlet of the crystallizer; According to the temperature difference of the cooling water at the inlet and outlet, combined with the billet cooling parameter and the heat acceptance degree, the heat accumulation coefficient of the current crystallizer is obtained; the temperature difference of the cooling water at the inlet and outlet is negatively correlated with the heat accumulation coefficient; the billet cooling parameter and the heat acceptance degree are positively correlated with the heat accumulation coefficient; The product of the billet cooling parameter and the heat receiving degree is used as the numerator, the temperature difference of the cooling water at the inlet and outlet is used as the denominator, and the fraction is used as the current heat accumulation coefficient; The method for obtaining the heat residual coefficient includes: The sum of all the accumulated heat coefficients in the current preset time domain neighborhood range is normalized to obtain the current heat residual coefficient.

2. The intelligent control system of a horizontal continuous casting machine for cast iron profiles according to claim 1, characterized in that: The method for obtaining the periodic displacement comprises: The rotation speed of the traction machine in one casting cycle is integrated with the operation time, and the integrated value is used as the cycle displacement.

3. The intelligent control system of a horizontal continuous casting machine for cast iron profiles according to claim 1, characterized in that: The method for obtaining the transfer time parameter includes: The ratio of the length of the crystallizer to the periodic displacement is taken as the transfer time parameter.

4. The intelligent control system for a horizontal continuous casting machine for cast iron profiles according to claim 1, characterized in that: The method for regulating the cooling intensity of the crystallizer according to the current heat residual coefficient includes: Get the initial parameters of the PID controller; Based on the current residual heat coefficient, the proportional coefficient in the initial parameter is adjusted to obtain a corrected proportional coefficient; and according to the current corrected proportional coefficient, the flow rate of the cooling water of the crystallizer is controlled.

5. The intelligent control system for a horizontal continuous casting machine for cast iron profiles according to claim 4, characterized in that: The method for obtaining the initial parameters of the PID controller includes: The initial parameters of the PID controller are obtained by the Ziegler–Nichols method.

6. The intelligent control system for a horizontal continuous casting machine for cast iron profiles according to claim 4, characterized in that: The method of adjusting the proportional coefficient in the initial parameters based on the current residual heat coefficient includes: The current residual heat coefficient plus a constant 1 is used as an amplification weight of the proportional coefficient, and the product of the amplification weight and the proportional coefficient is used as a correction proportional coefficient.

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