A cooling control method for rapid warm rolling process in a rolling mill and a strip.

Abstract

This application relates to the field of cold rolling technology for metal sheet and strip, and discloses a cooling control method for a rapid warm rolling process in a rolling mill, as well as the resulting sheet and strip. The control method includes: acquiring the strip to be rolled and heating it to a set temperature; acquiring the strip thickness and total reduction rate, and setting the total number of rolling passes based on the thickness and total reduction rate; acquiring the rolling speed, and setting the inlet emulsion flow rate for each rolling pass based on the rolling speed; and setting the outlet emulsion flow rate for each rolling pass based on the rolling speed and the inlet emulsion flow rate. After the set temperature, total number of rolling passes, inlet emulsion flow rate, and outlet emulsion flow rate are all set, strip rolling begins. This application precisely controls the emulsion spray flow rate and determines the optimal inlet and outlet flow rate ratio at the mill inlet and outlet to avoid sheet shape quality problems caused by excessively high temperatures.

Description

Technical Field

[0001] This application relates to the field of cold rolling technology for metal sheet and strip, and in particular, to a cooling control method and sheet / strip for a rapid warm rolling process in a rolling mill. Background Technology

[0002] Steel strip is a major product of the steel industry, and the production level and product quality of high value-added cold-rolled strip are important indicators of the modernization level of the steel industry. With the rapid development of various industries, users' demands for the variety and quality of cold-rolled strip are increasing, and the requirements for strip shape—a crucial indicator of quality—are also rising. The quality of the strip shape directly affects the stability of subsequent production processes and the machinability of the final product.

[0003] The 20-roll mill is the mainstream mill for producing high-quality strip steel of thin, hard specifications. During the cold rolling process in a 20-roll mill, the temperature of the strip steel is a crucial parameter affecting its quality and performance. Emulsion, as a lubricating and cooling medium, plays a vital role in the rolling process. In actual production, emulsion spray beams are installed at both the mill inlet and outlet to spray and cool the strip steel. Firstly, the inlet emulsion spray causes a temperature drop in the strip steel, preventing it from becoming too hot as it enters the deformation zone. Secondly, under conditions of large deformation and high deformation rate, the deformation zone generates a large amount of deformation heat and frictional heat, leading to a significant temperature rise in the strip steel. The outlet emulsion spray also causes a temperature drop, preventing excessively high temperatures during coiling and subsequent passes. During emulsion cooling, excessive emulsion flow rate can cause a drastic temperature drop, resulting in significant strip shape fluctuations. Furthermore, excessively low temperatures can prevent the finished product from meeting performance requirements. Conversely, insufficient emulsion flow rate leads to excessively high strip steel temperatures, causing strip shape quality issues. Therefore, it is crucial to maintain precise injection of inlet and outlet emulsion flow rates in conjunction with rolling speed. Summary of the Invention

[0004] The purpose of this application is to provide a cooling control method and strip for the rapid warm rolling process of a rolling mill, which solves the problem of strip shape quality caused by drastic temperature drop.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to one aspect of the embodiments of this application, a cooling control method for a rapid warm rolling process in a rolling mill is provided. The control method includes: acquiring a strip steel to be rolled and heating the strip steel to a set temperature; acquiring the thickness and total reduction rate of the strip steel and setting the total number of rolling passes based on the thickness and total reduction rate; acquiring the rolling speed and setting the inlet emulsion flow rate for each rolling pass based on the rolling speed; and setting the outlet emulsion flow rate for each rolling pass based on the rolling speed and the inlet emulsion flow rate.

[0007] In some embodiments, the set temperature range is 80°C to 100°C.

[0008] In some embodiments, the total number of rolling passes ranges from 4 to 9.

[0009] In some embodiments, in obtaining the rolling speed and setting the inlet emulsion flow rate for each rolling pass based on the rolling speed, the inlet emulsion flow rate is calculated as follows:

[0010] Q1 = α·v;

[0011] Q1 is the inlet emulsion flow rate, v is the rolling speed, and α is the first fitting coefficient obtained from the production test.

[0012] In some embodiments, when setting the outlet emulsion flow rate for each rolling pass based on the rolling speed and the inlet emulsion flow rate, the outlet emulsion flow rate is calculated as follows:

[0013] Q2 = (1-β·v)·Q1;

[0014] Q2 is the outlet emulsion flow rate, and β is the second fitting coefficient obtained from the production test.

[0015] In some embodiments, during the first pass, α = 4 and β = 5 × 10⁻⁶. -3 The rolling speed is controlled within the range of 100m / min to 150m / min.

[0016] In some embodiments, during the second pass, α = 5 and β = 8 × 10⁻⁶. -4 The rolling speed is controlled within the range of 450m / min to 500m / min.

[0017] In some embodiments, during the penultimate pass, α = 2.5 and β = 2.5 × 10⁻⁶. -4 The rolling speed is controlled within the range of 750m / min to 800m / min.

[0018] In some embodiments, for the remaining paving rounds excluding the first, second, and penultimate paving rounds, α = 3.5 and β = 5 × 10⁻⁶. -4 The rolling speed is controlled within the range of 700m / min to 750m / min.

[0019] According to one aspect of the present application, a strip is provided, which is prepared using the control method described above.

[0020] Compared with the prior art, the significant beneficial effects of the above technical solution of this application are as follows: (1) This application determines the optimal inlet and outlet flow ratio at the inlet and outlet of the rolling mill by precisely controlling the emulsion spray flow rate, so as to avoid plate shape quality problems caused by excessive temperature.

[0021] (2) This application provides a new approach to the cooling process of other thin and hard strip steel production, enabling more precise temperature drop control under conditions of greater deformation and higher rolling speed.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0023] The above and other features and advantages of this application will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0024] Figure 1 A flowchart of a control method according to an embodiment of this application is shown. Detailed Implementation

[0025] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0026] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0027] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0028] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0029] The technical solutions of the embodiments of this application are briefly described below:

[0030] According to some embodiments, such as Figure 1 As shown, this application provides a cooling control method for a rapid warm rolling process in a rolling mill, the control method comprising:

[0031] Step 101: Obtain the strip steel to be rolled and heat the strip steel to the set temperature;

[0032] Step 102: Obtain the thickness and total reduction rate of the strip, and set the total number of rolling passes based on the thickness and total reduction rate;

[0033] Step 103: Obtain the rolling speed and set the inlet emulsion flow rate for each rolling pass according to the rolling speed;

[0034] Step 104: Set the outlet emulsion flow rate for each rolling pass based on the rolling speed and the inlet emulsion flow rate.

[0035] Based on the above embodiments, this application selects a 20-roll mill in some embodiments, with inlet emulsion nozzles provided at the upper and lower ends of the strip at the mill inlet, and outlet emulsion nozzles provided at the upper and lower ends of the strip at the mill outlet. The inlet and outlet emulsion nozzles are used for lubricating and cooling the strip.

[0036] In step 101, the temperature is set to be controlled within the range of 80℃ to 100℃. This can be set according to actual needs. In some embodiments, the temperature is set to 90℃.

[0037] In step 102, the total number of rolling passes is selected based on the incoming thickness of the strip and the total reduction rate, ranging from 4 to 9 passes. In some embodiments, 7 passes are selected.

[0038] In step 103, the inlet emulsion flow rate for each rolling pass is calculated and set according to the rolling speed.

[0039] In step 104, the outlet emulsion flow rate for each rolling pass is calculated and set based on the rolling speed and the inlet emulsion flow rate.

[0040] After setting the temperature, total number of rolling passes, inlet emulsion flow rate, and outlet emulsion flow rate, the strip rolling process begins.

[0041] To enable those skilled in the art to better understand this application, the following will be combined with Figure 1 The details of this application are described in detail.

[0042] According to some embodiments, in step 103, the rolling speed is obtained, and the inlet emulsion flow rate for each rolling pass is set according to the rolling speed. The calculation method for the inlet emulsion flow rate is as follows:

[0043] Q1 = α·v;

[0044] Q1 is the inlet emulsion flow rate, v is the rolling speed, and α is the first fitting coefficient obtained from the production test.

[0045] According to some embodiments, in step 104, when setting the outlet emulsion flow rate for each rolling pass based on the rolling speed and the inlet emulsion flow rate, the calculation method for the outlet emulsion flow rate is as follows:

[0046] Q2 = (1-β·v)·Q1;

[0047] Q2 is the outlet emulsion flow rate, and β is the second fitting coefficient obtained from the production test.

[0048] According to some embodiments, in the first pass, α = 4, and β = 5 × 10⁻⁶. -3 The rolling speed is controlled within the range of 100m / min to 150m / min.

[0049] Based on the above embodiments, the rolling speed in the first pass is controlled within the range of 100 m / min to 150 m / min, i.e., not less than 100 m / min and not more than 150 m / min. Calculations show that the inlet emulsion flow rate is controlled within the range of 400 L / min to 600 L / min, and the outlet emulsion flow rate is controlled within the range of 150 L / min to 200 L / min. If a rolling speed of 150 m / min is selected, the inlet emulsion flow rate is 600 L / min, and the outlet emulsion flow rate is 150 L / min.

[0050] According to some embodiments, in the second pass, α = 5 and β = 8 × 10⁻⁶. -4The rolling speed is controlled within the range of 450m / min to 500m / min.

[0051] Based on the above embodiments, the rolling speed in the second pass is controlled within the range of 450 m / min to 500 m / min, i.e., not less than 450 m / min and not more than 500 m / min. Calculations show that the inlet emulsion flow rate is controlled within the range of 2250 L / min to 2500 L / min, and the outlet emulsion flow rate is controlled within the range of 1440 L / min to 1500 L / min. If a rolling speed of 470 m / min is selected, the inlet emulsion flow rate is 2350 L / min, and the outlet emulsion flow rate is 1466 L / min.

[0052] According to some embodiments, in the penultimate pass, α = 2.5 and β = 2.5 × 10⁻⁶. -4 The rolling speed is controlled within the range of 750m / min to 800m / min.

[0053] Based on the above embodiments, this application selects 7 total rolling passes in some embodiments. In the 7th pass, the rolling speed is controlled within the range of 750 m / min to 800 m / min, i.e., not less than 750 m / min and not more than 800 m / min. Based on calculations, the inlet emulsion flow rate is controlled within the range of 1875 L / min to 2000 L / min, and the outlet emulsion flow rate is controlled within the range of 1523 L / min to 1600 L / min. If a rolling speed of 800 m / min is selected, the inlet emulsion flow rate is 2000 L / min, and the outlet emulsion flow rate is 1600 L / min.

[0054] According to some embodiments, in the remaining paving rounds excluding the first, second, and penultimate paving rounds, α = 3.5 and β = 5 × 10⁻⁶. -4 The rolling speed is controlled within the range of 700m / min to 750m / min.

[0055] Based on the above embodiments, this application selects 7 total rolling passes in some embodiments. In some embodiments, in the 3rd pass, the rolling speed is controlled within the range of 700 m / min to 750 m / min, that is, not less than 700 m / min and not more than 750 m / min. The calculated inlet emulsion flow rate is controlled within the range of 2450 L / min to 2625 L / min, and the calculated outlet emulsion flow rate is controlled within the range of 1592 L / min to 1640 L / min. If a rolling speed of 720 m / min is selected, the inlet emulsion flow rate is 2520 L / min, and the outlet emulsion flow rate is 1612 L / min.

[0056] In the fourth pass, the rolling speed is controlled within the range of 700 m / min to 750 m / min, i.e., not less than 700 m / min and not more than 750 m / min. Based on calculations, the inlet emulsion flow rate is controlled within the range of 2450 L / min to 2625 L / min, and the outlet emulsion flow rate is controlled within the range of 1592 L / min to 1640 L / min. If a rolling speed of 740 m / min is selected, the inlet emulsion flow rate is 2590 L / min, and the outlet emulsion flow rate is 1632 L / min.

[0057] In the fifth pass, the rolling speed is controlled within the range of 700 m / min to 750 m / min, i.e., not less than 700 m / min and not more than 750 m / min. Based on calculations, the inlet emulsion flow rate is controlled within the range of 2450 L / min to 2625 L / min, and the outlet emulsion flow rate is controlled within the range of 1592 L / min to 1640 L / min. If a rolling speed of 750 m / min is selected, the inlet emulsion flow rate is 2625 L / min, and the outlet emulsion flow rate is 1640 L / min.

[0058] In the sixth pass, the rolling speed is controlled within the range of 700 m / min to 750 m / min, i.e., not less than 700 m / min and not more than 750 m / min. Based on calculations, the inlet emulsion flow rate is controlled within the range of 2450 L / min to 2625 L / min, and the outlet emulsion flow rate is controlled within the range of 1592 L / min to 1640 L / min. If a rolling speed of 750 m / min is selected, the inlet emulsion flow rate will be 2625 L / min, and the outlet emulsion flow rate will be 1640 L / min.

[0059] According to some embodiments, this application provides a strip fabricated using the control method described above.

[0060] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0061] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A cooling control method for a rapid warm rolling process in a rolling mill, characterized in that, The control method includes: Obtain the strip steel to be rolled and heat the strip steel to the set temperature; Obtain the thickness and total reduction rate of the strip, and set the total number of rolling passes based on the thickness and total reduction rate; Obtain the rolling speed, and set the inlet emulsion flow rate for each rolling pass based on the rolling speed. The calculation method for the inlet emulsion flow rate is as follows: The The inlet emulsion flow rate, the For rolling speed, the The first fitting coefficient is obtained based on the production test; The outlet emulsion flow rate for each rolling pass is set based on the rolling speed and the inlet emulsion flow rate. The calculation method for the outlet emulsion flow rate is as follows: The The outlet emulsion flow rate, the This is the second fitting coefficient obtained from production trials.

2. The control method according to claim 1, characterized in that, The set temperature range is 80℃~100℃.

3. The control method according to claim 1, characterized in that, The total number of rolling passes ranges from 4 to 9.

4. The control method according to claim 1, characterized in that, In the first pass, the The The rolling speed is controlled within the range of 100m / min to 150m / min.

5. The control method according to claim 1, characterized in that, In the second pass, the The The rolling speed is controlled within the range of 450m / min to 500m / min.

6. The control method according to claim 1, characterized in that, In the penultimate pass, the The The rolling speed is controlled within the range of 750m / min to 800m / min.

7. The control method according to claim 1, characterized in that, In the remaining courses excluding the first, second, and penultimate courses, the... The The rolling speed is controlled within the range of 700m / min to 750m / min.

8. A strip, characterized in that, The strip is prepared using the control method described in any one of claims 1 to 7.

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