Method for optimizing nozzle inner diameter of continuous casting machine secondary cooling chamber, nozzle and cooling system

Abstract

The present application relates to the technical field of continuous casting machine, in particular to a nozzle inner diameter optimization method of a secondary cooling chamber of a continuous casting machine, a nozzle and a cooling system. The nozzle inner diameter optimization method of the secondary cooling chamber of the continuous casting machine can collect the initial inner diameter and the initial spraying amount of the initial nozzle, combine the temperature difference before and after the cooling of the casting blank, calculate the best inner diameter and the best spraying amount for the best spraying of the cooling of the casting blank, so as to further improve the cooling effect on the casting blank. The present application can design nozzles with different inner diameters according to the steel grade characteristics of casting blanks of different materials, so as to select appropriate nozzles when a certain casting blank needs to be cooled, thereby improving the cooling effect and further improving the production efficiency.

Description

Technical Field

[0001] This invention relates to the field of continuous casting machine technology, and more specifically, to a method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine, the nozzle, and the cooling system. Background Technology

[0002] The secondary cooling chamber is an important component of a continuous casting machine, primarily used for secondary cooling of the billet pulled from the crystallizer. During continuous casting, the crystallizer initially solidifies the molten steel to form a billet shell of a certain thickness, while the secondary cooling chamber further cools the billet, ensuring complete solidification and bringing it to a temperature suitable for subsequent processing.

[0003] However, since the steel properties of billets made of different materials are different, using a single nozzle to cool the billets will result in poor cooling effect. Summary of the Invention

[0004] The present invention aims to provide a method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine, as well as the nozzle and cooling system, which can improve the cooling effect.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] In a first aspect, the present invention provides a method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine, comprising:

[0007] Collect the initial inner diameter D1 of the initial nozzle and the initial injection volume Q1;

[0008] The surface temperature of the billet is detected by a temperature sensor to collect the temperature change ΔT before and after cooling.

[0009] The optimal injection rate Q2 for cooling the billet is calculated using the formula ΔT=k·Q2+b;

[0010] The optimal inner diameter D2 of the cooled billet can be calculated using the formula D2=D1·√(Q1 / Q2);

[0011] Where k represents the proportionality coefficient of the influence of the coolant injection amount on the surface temperature change of the billet;

[0012] b represents the change in surface temperature of the billet when the coolant injection rate is zero.

[0013] In an optional implementation, it further includes:

[0014] Select or manufacture the optimal nozzle with an inner diameter of D2;

[0015] Replace the initial nozzle with the optimal nozzle;

[0016] Verify the optimal nozzle spray volume to obtain the actual spray volume Q3.

[0017] In an optional implementation, it further includes:

[0018] If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, then the optimal nozzle should be replaced with the initial nozzle.

[0019] The initial inner diameter D1 and initial injection quantity Q1 of the initial nozzle are re-acquired, and the optimal injection quantity Q2 is calculated using the formula.

[0020] In an optional implementation, it further includes:

[0021] If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, the optimal nozzle should be cleaned.

[0022] Secondly, the present invention provides a nozzle for the secondary cooling chamber of a continuous casting machine, wherein the inner diameter of the nozzle is obtained according to the aforementioned method for optimizing the inner diameter of the nozzle for the secondary cooling chamber of a continuous casting machine.

[0023] In an optional embodiment, the nozzle is provided with a slag discharge hole for passing the cleaning component through to clean iron slag and dirt.

[0024] In an optional embodiment, the inner diameter of the nozzle in the secondary cooling chamber of the continuous casting machine is D, wherein 30mm≤D≤50mm.

[0025] Thirdly, the present invention provides a cooling system for the secondary cooling chamber of a continuous casting machine, including a temperature sensor, a pipe assembly, an initial nozzle, and the aforementioned nozzle of the secondary cooling chamber of the continuous casting machine. The temperature sensor is connected to the pipe assembly; one of the initial nozzle and the nozzle is connected to and communicates with the pipe assembly; the temperature sensor is used to detect the surface temperature of the billet.

[0026] In an optional implementation, a processor is also included, which is electrically connected to a temperature sensor to receive the surface temperature of the billet detected by the temperature sensor and to calculate the temperature change ΔT, the optimal injection quantity Q2, and the optimal inner diameter D2.

[0027] In an optional embodiment, the cooling system of the secondary cooling chamber of the continuous casting machine also includes an injection quantity sensor connected to the nozzle, which is used to detect the injection quantity of the nozzle.

[0028] The beneficial effects of the nozzle inner diameter optimization method for the secondary cooling chamber of a continuous casting machine, the nozzle of the secondary cooling chamber of a continuous casting machine, and the cooling system of the secondary cooling chamber of a continuous casting machine provided in this embodiment of the invention include:

[0029] The nozzle inner diameter optimization method of the secondary cooling chamber of the continuous casting machine can calculate the optimal inner diameter and optimal spray volume for cooling the billet by collecting the initial inner diameter and initial spray volume of the initial nozzle and combining the temperature difference before and after billet cooling, thereby further improving the cooling effect on the billet.

[0030] Therefore, this invention can design nozzles with different inner diameters for different steel grades of cast billets, so that when a certain cast billet needs to be cooled, the appropriate nozzle can be selected, thereby improving the cooling effect and thus improving production efficiency. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a flowchart illustrating the method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine provided in this embodiment.

[0033] Figure 2 This is a flowchart illustrating the data acquisition and calculation steps provided in this embodiment.

[0034] Figure 3 This is a flowchart illustrating the verification steps provided in this embodiment. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0037] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0038] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0039] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0040] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0041] After high-temperature molten steel is poured into the continuous casting machine, the molten steel crystallizes in the continuous casting machine to form a billet shell, and the continuous casting machine pulls out the billet shell. The billet is then cooled by the cooling system, so that the billet can be completely solidified.

[0042] Understandably, continuous casting machines can operate on different types of steel. However, different types of steel have different thermal conductivity and solidification rates. Therefore, the cooling efficiency of the same cooling system for billets made from different types of steel will also be different.

[0043] To improve the cooling efficiency of the billet, this invention optimizes the nozzles of the secondary cooling chamber of a continuous casting machine. By adjusting the inner diameter of the nozzle, the spray volume of the nozzle is changed. Therefore, this invention provides a method for optimizing the inner diameter of the nozzles in the secondary cooling chamber of a continuous casting machine, so as to select or manufacture nozzles with suitable inner diameters according to the characteristics of different steels, thereby improving the cooling effect on the billet.

[0044] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating the method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine according to this embodiment. The method includes three main steps:

[0045] S1: Collect relevant data;

[0046] S2: Calculate the optimal inner diameter of the nozzle for the target billet based on the collected data;

[0047] S3: Verify whether the efficiency is improved by using a nozzle with the optimal inner diameter.

[0048] It should be noted that, in order to optimize the nozzle inner diameter, this invention provides a cooling system, which includes a temperature sensor, a pipe assembly, and a primary nozzle. Both the temperature sensor and the primary nozzle are connected to the pipe assembly. Coolant within the pipe assembly is sprayed from the nozzle to cool the billet. Furthermore, the temperature sensor is used to collect the temperature change ΔT of the billet before and after cooling, where ΔT can be calculated using Formula 1, as follows:

[0049] ΔT=T max -T min .

[0050] Among them, T max T represents the temperature of the billet before cooling. min This is the temperature at which the billet completely solidifies.

[0051] Please refer to Figure 2 , Figure 2 This is a flowchart illustrating the data acquisition and calculation steps provided in this embodiment. Specifically, S1 further includes the following steps:

[0052] S11: Connects the pipe assembly, temperature sensor, and original nozzle;

[0053] S12: The surface temperature of the billet is detected by a temperature sensor, and the temperature change ΔT on the surface of the billet is obtained using Formula 1.

[0054] S13: Collect the initial inner diameter D1 of the initial nozzle and the initial injection volume Q1.

[0055] It should be noted that in other embodiments, S13 can also be performed before S11, that is, the initial inner diameter D1 and the initial injection volume Q1 can be collected first, that is, the steps in other embodiments are S13-S11-S12.

[0056] Furthermore, after collecting the initial inner diameter D1, the initial injection quantity Q1, and the temperature change ΔT of the billet, the optimal injection quantity Q2 and the optimal inner diameter D2 can be calculated based on the collected data.

[0057] In this embodiment, a high-precision model of the relationship between cooling medium flow rate, pressure and billet temperature for different steel grades can be established through extensive data collection and in-depth analysis.

[0058] For example, please refer to the following: Figure 2 Specifically, S2 also includes the following steps:

[0059] S21: Using formula 2: ΔT=k·Q2+b, the optimal injection amount Q2 for cooling the billet is calculated;

[0060] S22: Using formula 3: D2=D1·√(Q1 / Q2), the optimal inner diameter D2 of the cooled billet can be calculated.

[0061] Understandably, Formulas 2 and 3 can be combined into Formula 4: D2=D1·√((k·Q1) / (ΔT-b)), and the optimal inner diameter D2 can be directly calculated using Formula 4;

[0062] It should be noted that k represents the proportionality coefficient of the influence of coolant injection quantity on the surface temperature change of the billet; b is the change in surface temperature of the billet when the coolant injection quantity is zero. k and b are coefficients obtained through fitting and optimization of hundreds of sets of experimental data.

[0063] Since the spray volume of a nozzle is affected by its inner diameter, nozzles with different inner diameters will have different spray volumes. Therefore, operators can refer to the optimal inner diameter to select or manufacture nozzles, thereby achieving the optimal spray volume and improving the cooling effect on the cast billet.

[0064] The initial nozzle-related data are shown in Table 1, as follows:

[0065]

[0066] The relevant data for the optimal nozzle are shown in Table 2, as follows:

[0067]

[0068] It should be noted that during use, the accumulation of iron slag and scale can cause partial blockage, resulting in the actual effective spray volume being approximately 70% of the calculated spray volume.

[0069] Based on the actual effective spray volume of the optimal nozzle and the initial nozzle, it can be seen that the optimal nozzle increases the spray volume by approximately 97.9% compared to the initial nozzle. Understandably, this increased spray volume leads to a larger contact area between the billet and the coolant, and also increases the coolant flow rate. The coolant can quickly remove a large amount of heat from the billet surface, thus improving the cooling effect. Furthermore, the increased coolant flow rate enhances its ability to flush away slag and scale, thereby improving clogging and further enhancing the cooling effect on the billet.

[0070] Furthermore, if the nozzle diameter is larger than 40.2 mm, it will result in excessively high pressure and a wide spray range, making it impossible to concentrate the strong cooling spray on the billet. Therefore, the inner diameter D of the nozzle is set between 30 mm and 50 mm, and the initial nozzle also adopts the minimum inner diameter of 30 mm, which is sufficient to cool the billet.

[0071] For different types of steel, due to differences in properties such as melting point ratio, the temperature change ΔT of different steel billets will also be different. Therefore, the optimal inner diameter obtained after calculation will also be different.

[0072] Therefore, suitable nozzles can be selected or manufactured for various types of steel billets, thereby improving the cooling effect on different billets.

[0073] It should be noted that after obtaining the optimal inner diameter, the obtained inner diameter must be verified first to avoid errors in the previous steps that would result in an inner diameter that is not optimal, thus affecting the cooling effect on the billet.

[0074] Please refer to Figure 3 , Figure 3 This is a flowchart illustrating the verification steps provided in this embodiment. Specifically, S3 further includes the following steps:

[0075] S31: Select or manufacture the optimal nozzle with an inner diameter of D2;

[0076] S32: Replace the initial nozzle with the optimal nozzle;

[0077] S33: Verify the optimal nozzle spray volume to obtain the actual spray volume Q3;

[0078] S34: If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, then the optimal nozzle will be replaced with the initial nozzle again.

[0079] The initial inner diameter D1 and initial injection quantity Q1 of the initial nozzle are re-acquired, and the optimal injection quantity Q2 is calculated using the formula.

[0080] S35: If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, clean the optimal nozzle.

[0081] It should be noted that the cooling system of the secondary cooling chamber of the continuous casting machine in this embodiment also includes an injection quantity sensor, which is used to detect the injection quantity of the optimal nozzle in order to detect the actual injection quantity Q3.

[0082] If the difference between the optimal injection quantity Q2 and the actual injection quantity Q3 is greater than 1m 3 If the difference is / h, the optimal nozzle should be cleaned first to remove dirt and deposits; if the difference is still greater than 1m 3 If the data is / h, there may be an error in the data acquisition and calculation process, and the data acquisition and calculation need to be repeated. If the data obtained from the re-acquisition and calculation is the same as the previous data, there may be an error in the selection of the nozzle or a large error in the manufacturing process.

[0083] If, in the early stages of using the optimal nozzle, the difference between the actual injection volume Q3 and the optimal injection volume Q2 is within 1m... 3 / h; however, after a period of use, the difference between the actual injection quantity Q3 and the optimal injection quantity Q2 is greater than 1m. 3 The / h error rate may be due to sediment gradually accumulating during use, thus affecting the spray volume.

[0084] To facilitate cleaning of the nozzle, this embodiment has a slag discharge hole on the nozzle for the cleaning component to pass through in order to clean iron slag and dirt.

[0085] Based on the above optimization method, this embodiment provides a cooling method for the secondary cooling chamber of a continuous casting machine, which includes a temperature sensor, a processor, an injection quantity sensor, a pipe assembly, an initial nozzle, and a nozzle for the secondary cooling chamber of the continuous casting machine.

[0086] First, the initial nozzle is connected to the pipe assembly and made to communicate with the pipe assembly. Then, the coolant is sprayed out using the initial nozzle to cool a casting. The temperature of the casting before and after cooling is collected by a temperature sensor, and the spray volume is collected by a spray volume sensor.

[0087] In this embodiment, the temperature sensor, the injection volume sensor, and the processor are all connected to the piping assembly, thereby using the temperature sensor to detect the surface temperature of the billet and using the injection volume sensor to detect the injection volume of the initial nozzle and the nozzle of the secondary cooling chamber of the continuous casting machine.

[0088] The processor receives temperature signals from the temperature sensor and injection quantity signals from the injection quantity sensor, and calculates the temperature change ΔT, optimal injection quantity Q2, and optimal inner diameter D2 based on the initial nozzle inner diameter. Subsequently, the nozzle for the secondary cooling chamber of the continuous casting machine is selected or manufactured according to the optimal inner diameter and optimal injection quantity.

[0089] Understandably, the inner diameter of the nozzle in the secondary cooling chamber of the continuous casting machine is calculated based on the nozzle inner diameter optimization method for the secondary cooling chamber of the continuous casting machine. Therefore, the nozzle in the secondary cooling chamber of the continuous casting machine is the optimal nozzle.

[0090] Finally, the original nozzle is removed from the piping assembly, and the nozzle of the secondary cooling chamber of the continuous casting machine is connected to and in communication with the piping assembly to cool the remaining slabs. It should be noted that the slabs cooled by the nozzles of the secondary cooling chamber of the continuous casting machine are from the same batch of slabs and are formed from the same type of steel as those cooled by the initial nozzles.

[0091] In summary, this invention provides a method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine. By collecting the initial inner diameter and initial spray volume of the initial nozzle, and combining the temperature difference before and after the billet cooling, the optimal inner diameter and optimal spray volume for the optimal spray for billet cooling are calculated, thereby further improving the cooling effect on the billet.

[0092] Therefore, this invention can design nozzles with different inner diameters for different steel grades of cast billets, so that when a certain cast billet needs to be cooled, the appropriate nozzle can be selected, thereby improving the cooling effect and thus improving production efficiency; moreover, it can save energy costs and avoid waste. According to statistics, it can save approximately 3.276 million yuan in energy costs per year.

[0093] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine, characterized in that, include: Collect the initial inner diameter D1 of the initial nozzle and the initial injection volume Q1; The surface temperature of the cast billet is detected by a temperature sensor to collect the temperature change ΔT before and after cooling, where ΔT = T. max -T min ; The optimal injection rate Q2 for cooling the billet was calculated using the formula ΔT=k·Q2+b. The optimal inner diameter D2 for cooling the billet is calculated using the formula D2=D1·√(Q1 / Q2); Among them, T max T represents the temperature of the billet before cooling. min The temperature at which the billet completely solidifies; k represents the proportionality coefficient of the influence of the coolant injection volume on the surface temperature change of the billet; b represents the change in surface temperature of the billet when the amount of coolant injected is zero.

2. The method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine according to claim 1, characterized in that, Also includes: Select or manufacture the optimal nozzle with an inner diameter of D2; Replace the initial nozzle with the optimal nozzle; Verify the injection volume of the optimal nozzle to obtain the actual injection volume Q3.

3. The method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine according to claim 2, characterized in that, Also includes: If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, then the optimal nozzle is replaced with the initial nozzle again. The initial inner diameter D1 and initial injection quantity Q1 of the initial nozzle are re-acquired, and the optimal injection quantity Q2 is calculated using the formula.

4. The method for optimizing the nozzle inner diameter of the secondary cooling chamber of a continuous casting machine according to claim 2, characterized in that, Also includes: If the ratio between the optimal injection quantity Q2 and the actual injection quantity Q3 is Q3 / Q2 < 70%, the optimal nozzle should be cleaned.

5. A nozzle for the secondary cooling chamber of a continuous casting machine, characterized in that, The inner diameter of the nozzle is obtained by the nozzle inner diameter optimization method for the secondary cooling chamber of a continuous casting machine according to any one of claims 1-4.

6. The nozzle of the secondary cooling chamber of the continuous casting machine according to claim 5, characterized in that, The nozzle is provided with a slag discharge hole for allowing the cleaning component to pass through in order to clean iron slag and dirt.

7. The nozzle of the secondary cooling chamber of the continuous casting machine according to claim 5, characterized in that, The inner diameter of the nozzle in the secondary cooling chamber of the continuous casting machine is D, where 30mm≤D≤50mm.

8. A cooling system for the secondary cooling chamber of a continuous casting machine, characterized in that, The system includes a temperature sensor, a piping assembly, an initial nozzle, and a nozzle for the secondary cooling chamber of a continuous casting machine as described in any one of claims 5-7, wherein the temperature sensor is connected to the piping assembly; one of the initial nozzle and the nozzle is connected to and communicates with the piping assembly; and the temperature sensor is used to detect the surface temperature of the cast billet.

9. The cooling system of the secondary cooling chamber of a continuous casting machine according to claim 8, characterized in that, It also includes a processor, which is electrically connected to the temperature sensor, for receiving the surface temperature of the billet detected by the temperature sensor, and calculating the temperature change ΔT, the optimal injection quantity Q2, and the optimal inner diameter D2.

10. The cooling system of the secondary cooling chamber of a continuous casting machine according to claim 8, characterized in that, The cooling system of the secondary cooling chamber of the continuous casting machine also includes an injection volume sensor connected to the nozzle, which is used to detect the injection volume of the nozzle.

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