Rolling box bending roller gap compensation control method

Abstract

The invention relates to a roll gap compensation control method for a bending roll of a coil box, which comprises the following steps: step 1, initializing the roll gap compensation of the bending roll, step 2, setting a roll gap compensation index value of the bending roll transmitted by a model, step 3, acquiring the roll gap compensation value of the bending roll, step 4, calculating by a roll gap calculation module of the bending roll, and step 5, calculating the roll gap compensation value of the bending roll. And 5, correcting the current setting by using the latest calculated roll gap value. According to the scheme, the roll gap of the bending roll of the hot coil box is automatically compensated by distinguishing different thicknesses of the intermediate billets through the same tapping mark, the situation that at least one operator monitors and intervenes in real time for 24 hours in a hot coil box area is changed, full-automatic control over the bending roll of the hot coil box is achieved, the automatic steel rolling level is improved, and the production efficiency is improved. And meanwhile, surface scratches, scrap steel faults and the like caused by poor roll shape of the middle roll are reduced.

Description

Technical Field

[0001] The invention relates to a control method, in particular to a roll gap compensation control method for a hot coil box bending roll, and belongs to the technical field of automatic control. Background Art

[0002] Since the second technical transformation of Meigang's 1422 hot rolling production line was put into use, the hot coil box of the 1422 hot rolling production line has played a decisive role in improving the rolling stability, product specification expansion, product quality and production capacity of Meigang's 1422 production line.

[0003] Through continuous improvement of the site and control, under normal circumstances, the hot coil box equipment operates stably when rolling ordinary steel grades. However, when the incoming material discharge mark and incoming material specifications of the hot coil box change, in order to ensure the coil shape and coiling stability of the hot coil box, the operator will manually correct the bending roller gap based on production experience. This situation of manual intervention based on the operator's experience is relatively arbitrary, or the operator does not intervene in the bending roller gap compensation in time, which often leads to poor coil shapes such as the middle coil in the hot coil box being out of round and the coil shape being loose. The poor coil shape often causes scratches on the surface of the strip during the unwinding process, and often impacts the on-site production equipment, seriously affecting the on-site service life of the production equipment. As a result, many scrap steels are caused every year. Since the hot coil box is located in the next process of rough rolling, once a scrap steel failure occurs in the hot coil box area, the number of scrap steel blocks will be at least two or more. The large amount of scrap steel and the long processing time are contrary to the company's cost reduction and efficiency improvement. If operator intervention is required, there will be at least one operator in the hot coil box area watching the production 24 hours a day. The operator will intervene in the bending roller gap compensation 10 times or more a day, and the number of strip steel blocks intervened each time is about 10. With the advancement of smart manufacturing in the hot rolling production line, steel rolling is facing the problem of less-manned / unmanned operation. Therefore, there is an urgent need to develop a hot coil box bending roller gap compensation control method to solve the above problems.

[0004] After searching for new information, the following two papers involve the roll gap of the hot coil box bending roll:

[0005] (1) Paper 1, titled "Mathematical Model of Bending Roller Control for the Second Generation Hot Coil Box", proposed mathematical models for the second generation hot coil box bending rollers in terms of roll gap setting, roll gap control, and bending roller lifting speed. Firstly, based on the principle of equal curvature method, a theoretical model for the setting of the roll gap of the bending roller was proposed, and an empirical model for the setting of the roll gap was given in combination with the structural characteristics of the second generation hot coil box bending roller and engineering practice. Secondly, a nonlinear mathematical model for roll gap control was established based on the mechanical structural parameters of the bending roller, thus laying the foundation for the precise adjustment of the roll gap of the bending roller. Thirdly, a new bending roller lifting speed theory combining the tracking principle and the coil diameter calculation principle was proposed, which solved the problem of the difficulty in controlling the bending roller lifting during the coiling process. Finally, the correctness and practicality of the proposed mathematical model were verified by engineering practice.

[0006] This paper discusses the second generation hot coil box. The inlet and outlet bending rollers of the second generation hot coil box are adjusted by different hydraulic cylinders, so the roller gap can be controlled more accurately and flexibly. The bending roller control mathematical model is not only advanced but also very practical, but it is not suitable for the first generation hot coil box. The present invention is a hot coil box bending roller gap compensation control method invented for the first generation hot coil box, so there is an essential difference between the two.

[0007] (2) Paper 2, title: "Improvement of Functional Accuracy of Hot Coil Box Coiling Station", in order to improve the accuracy of Meishan Steel's hot coil box coiling station, through comprehensive testing, the original coil control program was optimized, so that the functional accuracy of the hot coil box coiling station was improved, and the rolling quality of the strip was also improved.

[0008] "3.2.4 Bending Roll Gap Control" in the paper states: Bending roll gap control includes three aspects: bending roll horizontality control, roll gap calibration accuracy control and roll gap offset value control. It is also closely related to the matching of upper and lower bending roll speeds. These four aspects determine the size of the initial coil diameter, the initial cylindricity of the coreless coil, and are related to scratches on the strip surface.

[0009] The offset value of the bending roll gap is related to the landing point of the strip head and the size of the initial coil diameter. After field testing, the landing point of the strip head is located at the lower 1 / 3 of the upper flower rack, and the coil shape is optimal. The corresponding data table of the intermediate billet thickness and the offset value of the bending roll gap is given. This is the content of the paper involving the offset value of the bending roll gap, but the main focus of the paper is completely different from the content of the invention.

[0010] The control method of the present invention realizes automatic compensation control by using the control program based on the operator's on-site operation experience. Through the cooperation of the process control program and the basic automatic control program, the automatic compensation correction of the hot coil box bending roll gap of the same steel tapping mark and different intermediate billet thickness is realized, reducing the randomness and misoperation of manual operation. It is completely different from the content of the above invention patent. Summary of the invention

[0011] The present invention is aimed at the problems existing in the prior art, and provides a hot coil box bending roller gap compensation control method. This technical solution is aimed at the operator manually intervening in the bending roller gap compensation and correcting the hot coil box bending roller gap when the incoming material tapping mark and incoming material specifications of the hot coil box change. The control method of the present invention realizes automatic compensation control through the control program based on the operator's on-site operation experience, reducing the randomness, lag, and even misoperation of manual operation. Through the collaboration of the process control program and the basic automation control program, the automatic compensation of the hot coil box bending roller gap for different intermediate billet thicknesses with the same tapping mark is realized, which not only changes the hot coil box area to have at least one operator to monitor and intervene in real time 24 hours a day, realizes the full automatic control of the hot coil box bending roller, and improves the level of automated steel rolling, but also reduces the surface scratches and scrap steel failures caused by poor coil shape of the intermediate coil, and promotes the company's extreme cost in-depth promotion in the production line.

[0012] In order to achieve the above object, the technical solution of the present invention is as follows: a method for controlling the gap compensation of a bending roll of a hot coil box, the method comprising the following steps:

[0013] Step 1: Initialization of bending roller gap compensation. According to the characteristics of the production line and the range of intermediate billet thickness, a default bending roller gap compensation value is selected as the default value for the initialization configuration of the bending roller gap compensation initialization module.

[0014] (1) According to the process requirements, the intermediate billet thickness classification rules are formulated. The intermediate billet thickness classification variable is represented by cbxgapTbl and is divided into nine grades.

[0015] Taking Meishan Steel's 1422 hot rolling production line as an example, the intermediate skin classification variables cbxgapTbl[0..9] are 26, 28, 30, 32, 34, 36, 38, 40.1, and 50 respectively.

[0016] (2) configuring the default bending roller gap compensation value -12 corresponding to the index value 17, that is, all the initial values ​​of the bending roller gap compensation are configured to the value -12 of the interpolation table corresponding to index 17;

[0017] Step 2: The model transfers the setting of the bending roller gap compensation index value. The intermediate roller table model obtains the bending roller gap compensation index value corresponding to the different intermediate billet thicknesses of the tapping mark from "Table 1, Steel Type Specification Table" according to the tapping mark, and uses it as the model setting bending roller gap compensation index. When the intermediate roller table model generates an external recording event, the index value is sent out.

[0018] (1) "Table 1, Steel Grade Specification Table", a new bending roll gap compensation value index variable grade_num_cbx is added. This variable is divided into grades according to the intermediate skin thickness, and the bending roll gap compensation value index can be configured. The same steel tapping mark can be used to configure the bending roll gap compensation index value according to different intermediate billet thicknesses.

[0019] (2) When the strip calls the intermediate roller model to execute and generate an external record event, the model reads the corresponding bending roller gap compensation index value based on the strip's tapping mark and the intermediate billet thickness, and sends it to the public variable point as a setting.

[0020] Step 3: Obtain the bending roller gap compensation value. The basic automation control system obtains the compensation value corresponding to "Table 2, bending roller gap compensation value process table" according to the received bending roller gap compensation index value.

[0021] (1) The bending roller gap compensation value module reads the value of the common variable point, that is, the bending roller gap compensation index value.

[0022] (2) Find the compensation value corresponding to the bending roller gap compensation index value through "Table 2, bending roller gap compensation value process table", step 4: bending roller gap calculation module performs calculation, and recalculates the bending roller gap calculation according to the compensation value obtained in the previous step. The bending roller gap calculation formula is as follows:

[0023] TBRoll_Gap = CBOX_Thickness* coefficient + constant value + compensation value, where:

[0024] TBRoll_Gap: bending roller gap setting value

[0025] CBOX_Thickness: Thermal thickness of the middle roll

[0026] Where: CBOX_Thickness = rmx_thick*expansion, rmx_thick is the thickness of the intermediate billet in the cold state, expansion is the thermal expansion coefficient

[0027] Coefficient: The general value of the coefficient is between [1,2]. Taking Meishan Steel 1422 hot rolling production line as an example, the coefficient is 1.08.

[0028] Constant value: This value is related to the hot coil box bending roll equipment and is the result of data fitting collected by operators based on their long-term field experience. Taking the Meishan Steel 1422 hot rolling production line as an example, this value is: 22.42

[0029] Compensation value: divided into the following two cases

[0030]

[0031] Therefore, TBRoll_Gap = rmx_thick*expansion*coefficient+constant value+compensation value. Taking Meishan Steel 1422 hot rolling production line as an example, TBRoll_Gap = rmx_thick*expansion*1.08+22.42+compensation value.

[0032] Step 5: Use the latest calculated roll gap value to correct the current setting. Get the latest calculated bending roll gap setting value. When the strip enters the hot coil box area, if the latest calculated bending roll gap value deviates from the initial setting by more than 1, use the deviation to correct the initial setting of the hot coil box bending roll gap.

[0033] Compared with the prior art, the present invention has the following advantages: 1. This technical solution and method have changed the traditional reliance on manual experience, and the operator's on-site operating experience is automatically compensated and controlled through the control program, reducing the randomness and misoperation of manual operation; 2. Through the collaboration of the process control program and the basic automation control program, the automatic compensation correction of the hot coil box bending roller gap is realized. It has changed the dependence on manual labor, reduced the labor intensity of operators, and improved the level of automated steel rolling. The application of this method reduces surface scratches and scrap steel failures caused by poor coil shape in the middle coil, and promotes the company's in-depth promotion of extreme cost in the production line; 3. The control method of the present invention realizes automatic compensation control of the operator's on-site operating experience through the control program, reducing the randomness and misoperation of manual operation. Through the collaboration of process control programs and basic automation control programs, automatic compensation and correction of the hot coil box bending roller gap for different intermediate billet thicknesses at the same steel tapping mark is realized. This not only changes the dependence on manual labor, reduces the labor intensity of operators, and improves the level of automated steel rolling, but also reduces surface scratches and scrap steel failures caused by poor intermediate coil shape, helping to promote the company's extreme cost in-depth promotion on the production line. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is the control process of bending roller gap compensation;

[0035] Figure 2 This is a schematic diagram of the control flow of Example 2. DETAILED DESCRIPTION

[0036] In order to deepen the understanding of the present invention, the present embodiment is described in detail below with reference to the accompanying drawings.

[0037] Example 1: See Figure 1 A method for controlling the gap compensation of a hot coil box bending roller comprises the following steps:

[0038] Step 1: Initialization of bending roller gap compensation. According to the characteristics of the production line and the range of intermediate billet thickness, a default bending roller gap compensation value is selected as the default value for the initialization configuration of the bending roller gap compensation initialization module.

[0039] (1) According to the process requirements, the intermediate billet thickness classification rules are formulated. The intermediate billet thickness classification variable is represented by cbxgapTbl and is divided into nine grades.

[0040] Taking Meishan Steel's 1422 hot rolling production line as an example, the intermediate skin classification variables cbxgapTbl[0..9] are 26, 28, 30, 32, 34, 36, 38, 40.1, and 50 respectively.

[0041] (2) configuring the default bending roller gap compensation value -12 corresponding to the index value 17, that is, all the initial values ​​of the bending roller gap compensation are configured to the value -12 of the interpolation table corresponding to index 17;

[0042] Step 2: The model transfers the setting of the bending roller gap compensation index value. The intermediate roller table model obtains the bending roller gap compensation index value corresponding to the different intermediate billet thicknesses of the tapping mark from "Table 1, Steel Type Specification Table" according to the tapping mark, and uses it as the model setting bending roller gap compensation index. When the intermediate roller table model generates an external recording event, the index value is sent out.

[0043] (1) "Table 1, Steel Grade Specification Table", a new bending roll gap compensation value index variable grade_num_cbx is added. This variable is divided into grades according to the intermediate skin thickness, and the bending roll gap compensation value index can be configured. The same steel tapping mark can be used to configure the bending roll gap compensation index value according to different intermediate billet thicknesses.

[0044] Table 1, Steel Grade Specifications

[0045] Steel tapping mark One-dimensional array [intermediate billet thickness] index

[0046] (2) When the strip calls the intermediate roller model to execute and generate an external record event, the model reads the corresponding bending roller gap compensation index value based on the strip's tapping mark and the intermediate billet thickness, and sends it to the public variable point as a setting.

[0047] Step 3: Obtain the bending roller gap compensation value. The basic automation control system obtains the compensation value corresponding to "Table 2, bending roller gap compensation value process table" according to the received bending roller gap compensation index value.

[0048] Table 2, bending roller gap compensation value process table

[0049]

[0050]

[0051] (1) The bending roller gap compensation value module reads the value of the common variable point, that is, the bending roller gap compensation index value.

[0052] (2) Find the compensation value corresponding to the bending roller gap compensation index value through "Table 2, bending roller gap compensation value process table", step 4: bending roller gap calculation module performs calculation, and recalculates the bending roller gap calculation according to the compensation value obtained in the previous step. The bending roller gap calculation formula is as follows:

[0053] TBRoll_Gap = CBOX_Thickness* coefficient + constant value + compensation value, where:

[0054] TBRoll_Gap: bending roller gap setting value

[0055] CBOX_Thickness: Thermal thickness of the middle roll

[0056] Where: CBOX_Thickness = rmx_thick*expansion, rmx_thick is the thickness of the intermediate billet in the cold state, expansion is the thermal expansion coefficient

[0057] Coefficient: The general value of the coefficient is between [1,2]. Taking Meishan Steel 1422 hot rolling production line as an example, the coefficient is 1.08.

[0058] Constant value: This value is related to the hot coil box bending roll equipment and is the result of data fitting collected by operators based on their long-term field experience. Taking the Meishan Steel 1422 hot rolling production line as an example, this value is: 22.42

[0059] Compensation value: divided into the following two cases

[0060]

[0061] Therefore, TBRoll_Gap = rmx_thick*expansion*coefficient+constant value+compensation value. Taking Meishan Steel 1422 hot rolling production line as an example, TBRoll_Gap = rmx_thick*expansion*1.08+22.42+compensation value.

[0062] Step 5: Use the latest calculated roll gap value to correct the current setting. Get the latest calculated bending roll gap setting value. When the strip enters the hot coil box area, if the latest calculated bending roll gap value deviates from the initial setting by more than 1, use the deviation to correct the initial setting of the hot coil box bending roll gap.

[0063] Example 2: Taking AP0540D1 produced by Meishan 1422 hot rolling mill as an example, the intermediate billet thickness of this steel grade in the cold state is 40, and a hot coil box bending roll gap compensation control method is applied. The control process is as follows: Figure 2 As shown:

[0064] Step 1: Initialization of bending roller gap compensation,

[0065] Bending roller gap compensation initialization module. According to the characteristics of Meishan Steel 1422 hot rolling production line, the intermediate billet thickness is most likely between (38,40]. Through field test measurements, a default bending roller gap compensation value of -12 is given for the initialization configuration of the bending roller gap compensation initialization module.

[0066] Step 2: Model transfer bending roller gap compensation index value setting,

[0067] The model sets the bending roll gap compensation index module. The intermediate roll table model obtains the bending roll gap compensation index value 1 corresponding to the intermediate billet thickness 40 from the steel grade specification table according to the steel tapping mark AP0540D1, and uses it as the model setting bending roll gap compensation index. When the intermediate roll table model generates an external record, the index value is sent out.

[0068] The specification table of steel grade AP0540D1 is shown in the following table:

[0069] Steel tapping mark grade_name AP0540D1 One-dimensional array grade_num_cbx

[26] 17 One-dimensional array grade_num_cbx

[28] 13 One-dimensional array grade_num_cbx

[30] 26 One-dimensional array grade_num_cbx

[32] 9 One-dimensional array grade_num_cbx

[34] 22 One-dimensional array grade_num_cbx

[36] 5 One-dimensional array grade_num_cbx

[38] 18 One-dimensional array grade_num_cbx[40.1] 1 One-dimensional array grade_num_cbx

[50] 17

[0070] Step 3: Get the bending roller gap compensation value,

[0071] Module for obtaining bending roller gap compensation value: L1 obtains the compensation value corresponding to the bending roller gap compensation value process table from the following bending roller gap compensation value process table according to the received bending roller gap compensation index value 1: -13.

[0072] Bending roller gap compensation value process table:

[0073]

[0074]

[0075] Step 4: The bending roller gap calculation module performs calculations.

[0076] Bending roll gap calculation module. According to the compensation value obtained in the previous step: -13, recalculate the bending roll gap calculation. Since the thickness of the intermediate billet of steel grade AP0540D1 in the cold state is 40, the thermal expansion coefficient of this steel grade is: 1.016323, therefore:

[0077] (1) CBOX_Thickness: Thermal thickness of the middle roll = 40*1.016323 = 40.6529

[0078] (2) The compensation value of the bending roller is applicable to the case where the heat thickness of the intermediate roll is greater than 39. Therefore, the compensation value = the compensation value corresponding to the bending roller gap compensation process table - (-1) = -13 - (-1) = -12

[0079] (3) Bending roller gap TBRoll_Gap = thermal thickness of the middle roll * 1.08 + 22.42 + compensation value

[0080] =40.6529*1.08+22.42+(-12)

[0081] =54.3252

[0082] Step 5: Use the latest calculated roll gap value to correct the current setting.

[0083] Get the latest calculated bending roll gap setting value of 54.3252. When the on-site strip lights up HMD51, that is, when it is about to enter the hot coil box, get the latest calculated bending roll gap value and correct the initial setting.

[0084] It should be noted that the above embodiments are not intended to limit the protection scope of the present invention, and equivalent changes 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 method for controlling the gap compensation of a hot coil box bending roller, characterized in that: The method comprises the following steps: Step 1: Initialization of bending roller gap compensation, Step 2: Model transfer bending roller gap compensation index value setting, Step 3: Get the bending roller gap compensation value, Step 4: The bending roller gap calculation module performs calculations. Step 5: Correct the current setting using the latest calculated roll gap value.

2. The hot coil box bending roller gap compensation control method according to claim 1 is characterized in that: Step 1: Initialization of bending roller gap compensation. According to the characteristics of the production line and the range of intermediate billet thickness, a default bending roller gap compensation value is selected as the default value for the initialization configuration of the bending roller gap compensation initialization module. (1) According to the process requirements, the intermediate billet thickness classification rules are formulated. The intermediate billet thickness classification variable is represented by cbxgapTbl and is divided into nine grades. The intermediate skin classification variables cbxgapTbl[0..9] are 26, 28, 30, 32, 34, 36, 38, 40.1, and 50 respectively; (2) The default bending roller gap compensation value -12 is configured to correspond to the index value 17, that is, all the initial values ​​of the bending roller gap compensation are configured to the value -12 of the interpolation table corresponding to the index 17.

3. The method for controlling the roll gap compensation of the hot coil box bending roll according to claim 2, characterized in that: Step 2: The model transfers the setting of the bending roller gap compensation index value. The intermediate roller table model obtains the bending roller gap compensation index value corresponding to the different intermediate billet thicknesses of the tapping mark from "Table 1, Steel Type Specification Table" according to the tapping mark, and sets the bending roller gap compensation index as the model. When the intermediate roller table model generates an external recording event, the index value is sent out. (1) "Table 1, Steel Grade Specification Table", a new bending roll gap compensation value index variable grade_num_cbx is added. This variable is graded according to the intermediate billet thickness and can be used to configure the bending roll gap compensation value index. This allows the same steel tapping mark to be used to configure the bending roll gap compensation index value according to different intermediate billet thicknesses. Table 1, Steel Grade Specifications (2) When the strip calls the intermediate roller model to execute and generate an external record event, the model reads the corresponding bending roller gap compensation index value based on the strip's tapping mark and the intermediate billet thickness, and sends it to the public variable point as a setting.

4. The method for controlling the roll gap compensation of the hot coil box bending roll according to claim 3 is characterized in that: Step 3: Obtain the bending roller gap compensation value. The basic automation control system obtains the compensation value corresponding to "Table 2, bending roller gap compensation value process table" according to the received bending roller gap compensation index value. (1) The bending roller gap compensation value module reads the value of the common variable point, that is, the bending roller gap compensation index value. (2) Find the compensation value corresponding to the bending roller gap compensation index value through "Table 2, bending roller gap compensation value process table", Table 2, bending roller gap compensation value process table 。 5. The hot coil box bending roller gap compensation control method according to claim 3 or 4, characterized in that: Step 4: The bending roller gap calculation module performs calculations. According to the compensation value obtained in the previous step, the bending roller gap calculation is recalculated. The bending roller gap calculation formula is as follows: TBRoll_Gap = CBOX_Thickness* coefficient + constant value + compensation value, where: TBRoll_Gap: bending roller gap setting value; CBOX_Thickness: thermal thickness of the middle roll; Where: CBOX_Thickness = rmx_thick*expansion, rmx_thick is the intermediate billet thickness in the cold state, expansion is the thermal expansion coefficient; Coefficient: The value of the coefficient is between [1,2]. Constant value: This value is related to the hot coil box bending roller equipment and is the result of data fitting collected by operators based on their long-term field experience; Compensation value: There are two cases: Therefore, TBRoll_Gap=rmx_thick*expansion*coefficient+constant value+compensation value.

6. The method for controlling the roll gap compensation of the hot coil box bending roll according to claim 5, characterized in that: Step 5: Use the latest calculated roll gap value to correct the current setting, obtain the latest calculated bending roll gap setting value, when the strip enters the hot coil box area, if the latest calculated bending roll gap value deviates from the initial setting by more than 1, use the deviation to correct the initial setting of the hot coil box bending roll gap.

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