A control method for improving the floating of the head of thin-gauge strip steel

Abstract

The present invention relates to a control method for improving the head flutter of thin-gauge strip steel, and the control method comprises the following steps: Step 1: data preparation module performs preparation; Step 2: calculation module performs calculation; Step 3: automatic control module performs control; The method not only greatly improves the head flutter problem of thin-gauge strip steel, but also ensures the plate shape control accuracy of all thin-gauge strip steels. While reducing the scrap rate of hot-rolled strip steel, the yield rate of hot-rolled production line is greatly improved, which contributes to the company's cost reduction and efficiency improvement.

Description

Technical Field

[0001] The invention relates to a control method, in particular to a control method for improving the floating of the head of a thin-gauge strip steel, and belongs to the technical field of hot rolling production control. Background Art

[0002] In the actual production of hot rolling, in order to solve the plate shape problem caused by laminar cooling, many steel grades are currently solved by micro-wave rolling. Micro-wave rolling is to set a certain amount of wave setting under the normal straightness calculation conditions of the final stand of the finishing rolling mill. The value of the bending roll force during the adjustment process is the set wave target value. However, although wave rolling can solve the plate shape problem of the entire length of some strips, it also brings new problems: the head of the strip is easy to rub the transition plate or roller after leaving the final stand of the finishing rolling mill in the wave state, causing the head of the strip to float, and folding or scrap steel in severe cases. It increases the cost of hot rolling scrap and is not conducive to improving the material quality of the hot rolling production line. Therefore, a new solution is urgently needed to solve this technical problem. Summary of the invention

[0003] The present invention aims at the problems existing in the prior art and provides a control method for improving the fluttering of the head of thin-gauge strip steel. This technical solution realizes micro-wave control by turning off the real-time adjustment function of the bending roll and configuring the minimum bending roll force. At the same time, it adopts temperature segmentation control to improve the double-sided wave problem of the patterned plate. This solution not only greatly improves the fluttering problem of the head of thin-gauge strip steel, but also ensures the plate shape control accuracy of all thin-gauge strip steels, reduces the scrap of hot-rolled strip steel plates, and greatly improves the yield rate of the hot-rolling production line, which contributes to the company's cost reduction and efficiency improvement.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows: a control method for improving the floating of the head of a thin-gauge strip steel, the control method comprising the following steps:

[0005] Step 1: Data preparation module is used for preparation;

[0006] Step 2: The calculation module performs calculation;

[0007] Step 3: The automation control module performs control.

[0008] As an improvement of the present invention, the data preparation module in step 1 is specifically as follows:

[0009] 1.1 According to the hot rolling archived rolling performance, the plate shape setting performance table (as shown in Table 1) is configured. The table configures the micro-wave configuration values ​​corresponding to different races of steel tapping marks and different thickness grades of strip steel finished product specifications;

[0010] 1.2L2 process control system flatness model, find the corresponding grade and thickness grade according to the outgoing steel mark and target width and thickness of the current strip, and read the micro-middle wave configuration value of the flatness setting actual performance table according to the grade and thickness grade keywords;

[0011] 1.3 Flatness setting module of L2 process control system, calculate the flatness setting of the current strip for seven stands according to the original data of the strip at the entrance of hot continuous rolling finishing mill, incoming material data such as actually measured temperature, thickness, width, flatness self-learning data of the previous strip, and flatness requirement target of the finished strip, etc.

[0012] As an improvement of the present invention, the calculation module in step 2 is specifically as follows:

[0013] L1 basic automation calculation module, after receiving the micro-middle wave configuration value and flatness setting issued by L2, judge whether the strip is rolled with micro-middle wave. If so, reduce the bending roll force setting given in the flatness setting issued by L2 according to the bending roll force adjustment configuration difference table (as shown in Table 2); if it is not rolled with micro-middle wave, judge whether there is a middle wave at the head of the strip. If there is, reduce the bending roll force setting given in the flatness setting issued by L2 after multiplying by a decay gain value according to the bending roll force adjustment configuration difference table (as shown in Table 2). Specific implementation steps:

[0014] 2.1 The L1 basic automation calculation module judges according to the received micro-middle wave configuration value and flatness setting data whether the strip is rolled with micro-middle wave. If it is rolled with micro-middle wave, execute the calculation in step 2.2. If it is not rolled with micro-middle wave, judge whether there is a middle wave at the head of the strip. If there is a middle wave at the head of the strip, execute the calculation in step 2.3. Otherwise, control according to the flatness setting issued by L2;

[0015] 2.2 According to the micro-middle wave configuration value, find the corresponding bending roll force adjustment amount according to the bending roll force adjustment configuration difference table (as shown in Table 2), multiply by the decay gain gain, and reduce the bending roll force setting given in the flatness setting issued by L2. If it is rolled with micro-middle wave, the decay gain gain takes the value of 1;

[0016] 2.3 If it is not rolled with micro-middle wave, judge whether there is a middle wave at the head of the strip. If there is, reduce the bending roll force setting given in the flatness setting issued by L2 after multiplying by a decay gain gain value according to the bending roll force adjustment configuration difference table (as shown in Table 2). If it is not rolled with micro-middle wave but there is a middle wave at the head of the strip, the decay gain gain takes the value of 0.3;

[0017] 2.4 If the bending roll force setting value in the L2 flatness setting updated by the L1 basic automation calculation module < hardware limit, the bending roll force setting value is given according to the hardware limit bending roll force.

[0018] As an improvement of the present invention, step 3: the automatic control module is specifically as follows:

[0019] 3.1 Before the last stand of the hot strip finishing mill bites the steel, the L1 basic automation control module controls the strip steel according to the updated shape setting calculated in the previous step.

[0020] 3.2 Until the last stand of the finishing mill bites the steel, the L1 basic automation control module controls the strip steel according to the shape setting issued by L2.

[0021] Compared with the prior art, the present invention has the following advantages: 1) This technical solution realizes the configuration of the micro-middle wave set value by steel type and specification through the L2 process control system, and automatically adjusts the bending roll force according to different micro-middle waves through the L1 basic electrical automation system, maximizing the "control" and "automation" advantages of the L2 control system and the L1 automation system. Through the L2 process control system, not only can fine control by steel type and specification be realized, but also this fine control can be dynamically adjusted according to the on-site working conditions and the production performance of the strip steel; 2) This method combines the L2 process control system and the L1 basic electrical automation system to solve the problem of the head of thin-gauge strip steel floating up; while solving the problem of the head of thin-gauge strip steel floating up, it can also ensure the micro-middle wave rolling state of the overall shape of the strip steel. This method can also be used to improve the problem of the head of thin-gauge strip steel floating up during non-micro-middle wave rolling; 4) In the experimental stage of this scheme, the folding incidence rate caused by the head of the strip steel floating up has decreased from 1% to 0.3%, and the repair incidence rate caused by folding per month is 0.5%. Compared with the same period last year, the repair has been reduced to 0.15%. The economic benefit = the reduction ratio of the head folding caused by floating up * annual output * repair cost = (0.5% - 0.15%) * 1.2 million tons * 100 yuan / ton = 420,000 yuan. It is initially estimated that at least 420,000 yuan of cost reduction and efficiency increase can be achieved for the company every year. Description of the Drawings

[0022] Figure 1 is the flow chart of the original control method;

[0023] Figure 2 A flow chart of a control method for improving the floating of the head of thin-gauge strip steel. Detailed Embodiments

[0024] To deepen the understanding of the present invention, the following detailed description of this embodiment is made with reference to the drawings.

[0025] Embodiment 1: A control method for improving the floating of the head of thin-gauge strip steel, as Figure 2Flow chart of a control method for improving the floating of the head of thin-gauge strip steel. According to the micro-middle-wave rolling and the wave shape of the strip steel head, the L1 basic automation control system automatically adjusts the bending roll force set by L2 according to the micro-middle-wave configurations of different steel grades and different thicknesses issued by the L2 system, avoiding folding caused by the floating of the strip steel. After the strip steel head passes through the strip stably, the strip steel shape is controlled according to the bending roll force set by L2, which can not only ensure the strip steel head shape, but also ensure the micro-middle-wave rolling state of the overall shape. This method has excellent initial production application effects on the production of thin-gauge pattern plates with micro-middle-wave rolling, and then is extended to the production control of all strip steels with head floating problems, effectively solving a series of production cost problems caused by the floating of the strip steel head during micro-middle-wave rolling.

[0026] The control method includes the following steps:

[0027] Step 1: Data preparation module;

[0028] Step 2: Calculation module;

[0029] Step 3: Automation control module.

[0030] The data preparation module in Step 1 is specifically as follows:

[0031] 1.1 Configure the shape setting actual performance table according to the hot continuous rolling archived rolling actual performance (as shown in Table 1). This table configures the micro-middle-wave configuration values corresponding to different races to which the steelmaking mark belongs and different thickness grades to which the finished strip steel specifications belong;

[0032] Table 1: Shape setting actual performance table

[0033] Race Thickness grade Micro medium wave configuration 5 2 15 5 102 20 13 103 20 13 104 20 25 201 20 25 203 25 25 301 30 25 302 30

[0034] 1.2 The shape model of the L2 process control system finds the corresponding race and thickness grade according to the steelmaking mark and target width and thickness of the current strip steel, and reads the micro-middle-wave configuration value of the shape setting actual performance table according to the race and thickness grade keywords;

[0035] 1.3 The shape setting module of the L2 process control system calculates the shape setting of the seven stands of the current strip steel according to the original data of the strip steel at the entrance of the hot continuous rolling finishing mill, the incoming material data such as the actually detected temperature, thickness, and width, the shape self-learning data of the previous strip steel, and the shape requirement target of the finished strip steel.

[0036] The calculation module in Step 2 is specifically as follows:

[0037] The L1 basic automation calculation module receives the micro-middle wave configuration value and shape setting issued by L2, and determines whether the strip is rolled with micro-middle wave. If so, it reduces the roll force setting in the shape setting issued by L2 according to the roll force adjustment configuration difference table (as shown in Table 2); if it is not rolled with micro-middle wave, it determines whether there is a middle wave at the head of the strip. If there is, it reduces the roll force setting in the shape setting issued by L2 after multiplying the roll force adjustment configuration difference table (as shown in Table 2) by an attenuation gain value. Specific implementation steps:

[0038] 2.1 The L1 basic automation calculation module makes a judgment based on the received micro-middle wave configuration value and shape setting data to determine whether the strip is rolled with micro-middle wave. If it is rolled with micro-middle wave, it executes the calculation in step 2.2. If it is not rolled with micro-middle wave, it determines whether there is a middle wave at the head of the strip. If there is a middle wave at the head of the strip, it executes the calculation in step 2.3. Otherwise, it controls according to the shape setting issued by L2;

[0039] 2.2 According to the micro-middle wave configuration value, find the corresponding roll force adjustment amount according to the roll force adjustment configuration difference table (as shown in Table 2), multiply it by the attenuation gain gain, and reduce the roll force setting in the shape setting issued by L2. If it is rolled with micro-middle wave, the attenuation gain gain takes the value of 1;

[0040] Table 2: Roll force adjustment configuration difference table

[0041] Micro medium wave configuration ≤10 ≤15 ≤20 ≤25 ＞25 Micro medium wave attenuation gain 1.0 1.0 1.0 1.0 1.0 Non-micro medium wave attenuation gain 0.3 0.3 0.3 0.3 0.3 Bending roll force adjustment amount 50*gain 130*gain 200*gain 260*gain 320*gain

[0042] 2.3 If it is not rolled with micro-middle wave, it determines whether there is a middle wave at the head of the strip. If there is, it reduces the roll force setting in the shape setting issued by L2 after multiplying the roll force adjustment configuration difference table (as shown in Table 2) by an attenuation gain gain value. If it is not rolled with micro-middle wave but there is a middle wave at the head of the strip, the attenuation gain gain takes the value of 0.3;

[0043] 2.4 If the roll force setting value in the L2 shape setting updated by the L1 basic automation calculation module < hardware limit, the roll force setting value is given according to the hardware limit roll force.

[0044] Step 3: The automation control module is as follows:

[0045] 3.1 Before the last stand of the hot strip mill finishing mill bites the steel, the L1 basic automation control module controls the strip according to the shape setting updated by the calculation in the previous step;

[0046] 3.2 After the last finishing mill bites the steel strip, the L1 basic automation control module controls the strip according to the shape setting issued by L2. This method realizes the given control of the micro-middle wave by steel type and specification through the L2 process control system, and automatically adjusts the bending roll force according to different micro-middle waves through the L1 basic electrical automation system, maximizing the "control" and "automation" advantages of the L2 control system and the L1 automation system, providing a solution direction for subsequent automated production. Through the L2 process control system, not only can the refined control by steel type and specification be realized, but also this refined control can be dynamically adjusted according to the changes in the on-site working conditions and the production performance of the strip. This control can be used not only to improve the problem of the head floating of the strip rolled with micro-middle wave, but also to solve the problem of the middle wave at the head of the strip in the case of non-micro-middle wave rolling, effectively improving the problem of the head floating of thin-specification strips.

[0047] Specific Embodiment 1: Taking the GR3180F2 of 1.8*1250 on the domestic 1422 hot continuous rolling production line as an example, a control method for improving the head floating of thin-specification strips, which is applied to the control of micro-middle wave rolling, is implemented as follows:

[0048] Step 1: Data preparation module;

[0049] 1.1 The shape model of the L2 process control system finds the corresponding grade 25 and thickness grade 302 according to the outgoing steel mark GR3180F2 of the current strip and the target width and thickness 1.8*1250. Read the micro-middle wave configuration value 30 of the shape setting actual performance table (as shown in Table 1) according to the keywords of grade 25 and thickness grade 302.

[0050] 1.2 The shape setting module of the L2 process control system calculates the shape setting of the current strip according to the original data of the strip at the entrance of the finishing mill of the hot continuous rolling, the incoming material data such as the actually detected temperature, thickness, and width, the shape self-learning data of the previous strip, and the shape requirement target of the finished strip. Among them, the bending roll force settings for the seven finishing mill stands are: 1209 KN, 1200 KN, 1200 KN, 1194 KN, 1200 KN, 1200 KN, 934 KN.

[0051] Step 2: Calculation module;

[0052] 2.1 The L1 basic automation calculation module receives the micro-middle wave configuration value and the shape setting issued by L2. Judges that the strip is rolled with micro-middle wave, and reduces the bending roll force given in the shape setting issued by L2 according to the bending roll force adjustment configuration difference table (as shown in Table 2).

[0053] 2.2 According to the micro medium wave configuration value 30, which is greater than 25, find the corresponding bending roll force adjustment amount 320 according to the bending roll force adjustment configuration difference table (as shown in Table 2), multiply it by the attenuation gain gain = 1, and reduce the bending roll force setting in the flatness setting issued by L2. Therefore, the bending roll force settings for the flatness setting of this strip steel after adjustment are: 1209 KN, 1200 KN, 1200 KN, 1194 KN, 1200 KN, 1200 KN, 614 KN.

[0054] Step 3: Automatic control module;

[0055] 3.1 Before the last stand of the hot continuous rolling finishing mill bites the steel, the L1 basic automatic control module controls the strip steel according to the flatness setting updated after calculation in the previous step, that is, controls the strip steel according to the bending roll force of the flatness setting of this strip steel after adjustment: 1209 KN, 1200 KN, 1200 KN, 1194 KN, 1200 KN, 1200 KN, 614 KN.

[0056] 3.2 Until after the last stand of the finishing mill bites the steel, the L1 basic automatic control module controls the strip steel according to the flatness setting issued by L2, that is, controls the strip steel according to the bending roll force settings of the seven finishing mill stands, which are: 1209 KN, 1200 KN, 1200 KN, 1194 KN, 1200 KN, 1200 KN, 934 KN.

[0057] Through the above steps, a control method for improving the head floating of thin gauge strip steel is realized.

[0058] Specific Embodiment 2: Taking the AQ0511K1 of 2.5 * 1023 on the domestic 1422 hot continuous rolling production line as an example, a control method for improving the head floating of thin gauge strip steel, which is applied to the control implementation steps of non-micro medium wave rolling, is as follows:

[0059] Step 1: Data preparation module;

[0060] 1.1 Configure the flatness setting actual performance table according to the hot continuous rolling archived rolling actual performance (as shown in Table 1). This table configures the micro medium wave configuration values corresponding to different races of the tapping mark and different thickness grades of the strip steel finished product specifications.

[0061] 1.2 The flatness model of the L2 process control system finds the corresponding race 13 and thickness grade 104 according to the tapping mark AQ0511K1 of the current strip steel and the target width and thickness 2.5 * 1023. Read the micro medium wave configuration value 20 of the flatness setting actual performance table according to the keywords of race 13 and thickness grade 104.

[0062] 3.1 The shape setting module of the L2 process control system calculates the shape settings of the current strip for the seven finishing mill stands based on the original data of the strip at the entrance of the hot continuous rolling finishing mill, the incoming material data such as the actually measured temperature, thickness, width, the shape self-learning data of the previous strip, and the shape requirement target of the finished strip. Among them, the bending roll force settings for the seven finishing mill stands are: 1203 KN, 1000 KN, 890 KN, 876 KN, 784 KN, 784 KN, 941 KN.

[0063] Step 2: Calculation module;

[0064] 2.1 The L1 basic automation calculation module receives the micro-middle wave configuration value and shape setting issued by L2. If it is determined that the strip is not rolled with a micro-middle wave but there is an intermediate wave at the head of the strip, after multiplying by a decay gain value according to the bending roll force adjustment configuration difference table (as shown in Table 2), the bending roll force given in the shape setting issued by L2 is reduced.

[0065] 2.2 The strip is not rolled with a micro-middle wave but there is an intermediate wave at the head of the strip, and the intermediate wave is 14.2. According to the bending roll force adjustment configuration difference table (as shown in Table 2), when 14.2 ≤ 15 for the intermediate wave, the corresponding bending roll adjustment amount is: 130 * gain = 130 * 0.3 = 39, and the bending roll force given in the shape setting issued by L2 is reduced. Therefore, after adjustment, the bending roll force settings for the shape setting of this strip are: 1203 KN, 1000 KN, 890 KN, 876 KN, 784 KN, 784 KN, 902 KN.

[0066] Step 3: Automation control module;

[0067] 3.1 Before the last stand of the hot continuous rolling finishing mill bites the strip, the L1 basic automation control module controls the strip according to the updated shape setting calculated in the previous step, that is, controls the strip according to the bending roll forces of the shape setting of this strip after adjustment: 1203 KN, 1000 KN, 890 KN, 876 KN, 784 KN, 784 KN, 902 KN.

[0068] 3.2 Until after the last stand of the finishing mill bites the strip, the L1 basic automation control module controls the strip according to the shape setting issued by L2, that is, controls the strip according to the bending roll force settings for the seven finishing mill stands which are: 1203 KN, 1000 KN, 890 KN, 876 KN, 784 KN, 784 KN, 941 KN.

[0069] Through the above steps, a control method for improving the floating of the head of thin-gauge strip steel is realized.

[0070] It should be noted that the above embodiments are not used to limit the protection scope of the present invention, and equivalent transformations or substitutions made on the basis of the above technical solutions all fall within the protection scope of the claims of the present invention.

Claims

1. A control method for improving the head floating of thin-gauge strip steel, characterized in that the control method comprises the following steps: Step 1: The data preparation module makes preparations; Step 2: The calculation module performs calculations; Step 3: The automatic control module conducts control; Among them, the specific content of Step 1 is as follows: 1.1 Configure the shape setting actual performance table according to the rolling actual performance archived in hot continuous rolling. This table configures the micro-middle wave configuration values corresponding to different races to which the tapping mark belongs and different thickness grades to which the finished strip specifications belong; 1.2 The shape model of the L2 process control system finds the corresponding race and thickness grade according to the tapping mark and target width and thickness of the current strip, and reads the micro-middle wave configuration value of the shape setting actual performance table according to the race and thickness grade keywords; 1.3 The shape setting module of the L2 process control system calculates the shape setting of the seven stands of the current strip according to the original data of the strip at the entrance of the finishing mill in hot continuous rolling, the actually detected incoming material data of temperature, thickness, and width, the shape self-learning data of the previous strip, and the shape requirement target of the finished strip; The specific steps of step 2 are as follows: 2.1 The L1 basic automation calculation module judges according to the received micro-middle wave configuration value and shape setting data whether the strip is rolled with micro-middle wave. If it is rolled with micro-middle wave, execute step 2.2 for calculation. If it is not rolled with micro-middle wave, judge whether there is a middle wave at the head of the strip. If there is a middle wave at the head of the strip, execute step 2.3 for calculation. Otherwise, control according to the shape setting issued by L2; 2.2 According to the micro-middle wave configuration value, find the corresponding roll bending force adjustment amount according to the roll bending force adjustment configuration difference table, multiply it by the attenuation gain gain, and reduce the roll bending force setting in the shape setting issued by L2. If it is rolled with micro-middle wave, the attenuation gain gain takes the value of 1; 2.3 If it is not rolled with micro-middle wave, judge whether there is a middle wave at the head of the strip. If there is, multiply it by an attenuation gain gain value according to the roll bending force adjustment configuration difference table, and reduce the roll bending force setting in the shape setting issued by L2. If it is not rolled with micro-middle wave but there is a middle wave at the head of the strip, the attenuation gain gain takes the value of 0.3; The specific steps of step 3 are as follows: 3.1 Before the last stand of the finishing mill in hot continuous rolling bites the strip, the L1 basic automation control module controls the strip according to the shape setting updated after the calculation in the previous step; 3.2 Until after the last stand of the finishing mill bites the strip, the L1 basic automation control module controls the strip according to the shape setting issued by L2.

2. The control method for improving the floating of the head of thin-gauge strip according to claim 1, characterized in that, step 2 further includes, 2.4 If the roll bending force setting value in the L2 shape setting updated by the L1 basic automation calculation module < hardware limit, the roll bending force setting value is set according to the roll bending force setting of the hardware limit.

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