A method and system for pre-adjusting the roll gap level of the first piece of steel in a finishing mill roll change

Abstract

The application discloses a roll gap horizontal pre-adjustment value setting method and system for the first piece of steel after roll replacement of a finish rolling mill, which comprises the following steps: calibrating the roll gap of the finish rolling mill; respectively calculating the difference between the rolling force deviations of the pressure heads on both sides of the rolling mill and the oil pressure sensor; calculating the roll gap horizontal pre-adjustment value based on a preset algebraic relation by using the rigidity of the rolling mill, the rack adjustment coefficient and the difference; and adjusting the roll gap horizontally according to the horizontal pre-adjustment value. The roll gap horizontal pre-adjustment value for the first piece of steel after roll replacement of the finish rolling mill is solved, and the deviation of the value given by experience is large, thereby avoiding the head folding defects and scrap steel caused by the deviation, and improving the rolling stability of the hot rolling production line.

Description

Technical Field

[0001] This invention relates to the field of hot rolling technology of steel, and in particular to a method and system for setting the roll gap level of the first piece of steel when changing rolls in a finishing mill. Background Technology

[0002] In the hot rolling process of steel, the work rolls of the finishing mill need to be replaced after rolling a certain number of strips; similarly, the support rolls need to be replaced periodically after rolling more strips. However, due to the differences in precision of different work rolls, support rolls, and their corresponding step pad positions, a truly level roll gap cannot be obtained after the mill completes the roll gap level calibration. At this point, operators need to provide a certain roll gap level pre-adjustment value to correct the roll gap level, which is a pre-adjustment value obtained based on the operator's long-term practical experience. If the given roll gap level pre-adjustment value is too large or exceeds the required threshold, it will cause the head of the first strip to fold when threaded into the finishing mill, and in more serious cases, it will lead to scrap steel. In addition, many hot rolling production lines cause more than 3 scrap steel incidents and more than 15 unplanned roll changes per year. Currently, operators mainly record different roll gap pre-adjustment values ​​for the first piece of steel based on different work rolls and step pad positions. They then use these values ​​to determine the pre-adjustment value by limiting the number of times they can be applied under the same conditions. However, when other conditions change, this empirical value is no longer applicable to the current situation, which leads to folding and scrap steel, making it impossible to improve the efficiency of the hot rolling process. Summary of the Invention

[0003] This application provides a method and system for setting the roll gap horizontal pre-adjustment value for the first strip of steel during the finishing mill roll change. This at least partially solves the technical problem in the prior art where errors in the given roll gap horizontal pre-adjustment value cause the head of the first strip to fold during the finishing mill strip threading process. This achieves the technical effect of avoiding head folding defects and scrap steel, and improving the rolling stability of the hot rolling production line.

[0004] Firstly, to solve the above-mentioned technical problems, embodiments of the present invention provide the following technical solutions:

[0005] A method for setting the roll gap horizontal pre-adjustment value for the first piece of steel during a finishing mill roll change includes:

[0006] The roll gap of the finishing mill is calibrated;

[0007] Calculate the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor;

[0008] Using the mill's rigidity, the stand adjustment coefficient, and the aforementioned differences, the pre-adjusted value for the roll gap level is calculated based on a preset algebraic relationship.

[0009] Adjust the roll gap level according to the above pre-adjusted level value.

[0010] Optionally, the above steps for calibrating the roll gap of the finishing mill also include:

[0011] The roll gap of the finishing mill is calibrated using the rolling force detected by the pressure head.

[0012] Optionally, before calculating the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, the above method further includes:

[0013] Record the rolling force data of the pressure head and hydraulic pressure sensor before each stand of the rolling mill is calibrated.

[0014] Optionally, the steps described above for calculating the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor further include:

[0015] Calculate the first rolling force deviation between the upper pressure head and the hydraulic pressure sensor on the transmission side;

[0016] Calculate the second rolling force deviation between the pressure head and the hydraulic sensor on the operating side;

[0017] The above difference is equal to the difference between the first rolling force deviation and the second rolling force deviation.

[0018] Optionally, the above-mentioned preset algebraic relations include:

[0019]

[0020] Where Level is the pre-adjustment value of the roll gap of the finishing mill stand, k is the stand adjustment coefficient, W is the stand stiffness, and dF DS For the first rolling force deviation, dF OS This is the second rolling force deviation.

[0021] Optionally, the step of adjusting the roll gap level according to the aforementioned pre-adjusted level value further includes:

[0022] If the result obtained based on the above-mentioned preset algebraic relationship is negative, it indicates that the roller gap on the pressing operation side is being performed; if it is positive, it indicates that the roller gap on the pressing drive side is being performed.

[0023] Optionally, the above methods also include:

[0024] Based on historical data, regression analysis was used to obtain the algebraic relationship between the stiffness data, rolling force deviation, adjustment coefficient, and roll gap level pre-adjustment value of the above-mentioned frame.

[0025] Secondly, a roll gap level pre-adjustment value setting system is provided for the first piece of steel changed at a finishing mill, the system comprising:

[0026] The calibration module is used to calibrate the roll gap of the finishing mill.

[0027] The difference calculation module is used to calculate the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, respectively.

[0028] The pre-adjustment value calculation module is used to calculate the roll gap horizontal pre-adjustment value based on a preset algebraic relationship using the mill's stiffness, the stand adjustment coefficient, and the above differences.

[0029] The adjustment module is used to adjust the roll gap level according to the pre-adjusted level value.

[0030] Thirdly, an electronic device is provided, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to perform the steps corresponding to the method described in the first aspect.

[0031] Fourthly, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, performs the steps corresponding to the method described in the first aspect.

[0032] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0033] Based on historical data, regression analysis was used to obtain the algebraic relationship between the stand stiffness data, rolling force deviation, adjustment coefficient, and roll gap level pre-adjustment value. Then, by utilizing the rolling force detected by the pressure heads and hydraulic pressure sensors on both sides of the mill (i.e., the operating side and the drive side) during calibration, and based on their interrelationships and differences, the adjustment direction and magnitude of the roll gap level for the first steel piece rolled were determined. The roll gap level was then corrected, ensuring accurate use of the pre-adjustment value even when other conditions change, thereby preventing the given roll gap level pre-adjustment value from exceeding the required error. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 A flowchart illustrating a method for setting the roll gap horizontal pre-adjustment value for the first piece of steel during a roll change in a finishing mill, as provided in this application;

[0036] Figure 2 A schematic diagram of the structure of a roll gap horizontal pre-adjustment value setting system for the first piece of steel changing rolls in a finishing mill, provided in this application;

[0037] Figure 3A schematic diagram of the structure of an electronic device provided in this application;

[0038] Figure 4 A schematic diagram of the regression equation provided in this application. Detailed Implementation

[0039] 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.

[0040] 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.

[0041] 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.

[0042] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the term "setup" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. Unless otherwise specified, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0044] This application provides a method and system for setting the roll gap horizontal pre-adjustment value for the first strip of steel during the finishing mill roll change. This improves upon the technical problem in the prior art where errors in the given roll gap horizontal pre-adjustment value cause the head of the first strip to fold during the finishing mill strip threading process. This achieves the technical effect of avoiding head folding defects and scrap steel, and improving the rolling stability of the hot rolling production line.

[0045] The technical solution of this application embodiment is to solve the above-mentioned technical problems, and the general idea is as follows:

[0046] Based on historical data, regression analysis was used to obtain the algebraic relationship between the stand stiffness data, rolling force deviation, adjustment coefficient, and roll gap level pre-adjustment value. Then, by utilizing the rolling force detected by the pressure heads and hydraulic pressure sensors on both sides of the mill (i.e., the operating side and the drive side) during calibration, and based on their interrelationships and differences, the adjustment direction and magnitude of the roll gap level for the first steel piece rolled were determined. The roll gap level was then corrected, ensuring accurate use of the pre-adjustment value even when other conditions change, thereby preventing the given roll gap level pre-adjustment value from exceeding the required error.

[0047] In the embodiments of this application, the following are provided: Figure 1 The method shown is a method for setting the roll gap horizontal pre-adjustment value for the first piece of steel during a finishing mill roll change, the method including steps S101 to S104:

[0048] Step S101: Calibrate the roll gap of the finishing mill;

[0049] Firstly, this embodiment is applicable to obtaining a true horizontal roll gap after the roll gap level of the rolling mill has been calibrated; therefore, it is necessary to calibrate the roll gap of the finishing mill first, wherein the calibration method is to use the rolling force detected by the pressure head to calibrate the roll gap of the finishing mill.

[0050] Step S102: Calculate the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, respectively;

[0051] The two sides of the rolling mill refer to the operating side and the drive side of the rolling mill; the rolling force of the pressure head sensor on the drive side is F. LC_ds The rolling force of the transmission-side hydraulic pressure sensor is F. PT_ds The rolling force of the operating side pressure head sensor is F. LC_os The rolling force of the operating side hydraulic pressure sensor is F. PT_os ;

[0052] The rolling force deviation between the drive-side pressure head and the hydraulic pressure sensor is:

[0053] dF DS =F PT_ds -F LC_ds (1)

[0054] The rolling force deviation between the operating side pressure head and the hydraulic pressure sensor is:

[0055] dF OS =F PT_os -F LC_os (2)

[0056] The difference is:

[0057] dF DS -dFOS (3)

[0058] Step S103: Using the mill's rigidity, the stand adjustment coefficient, and the above-mentioned difference, the roll gap horizontal pre-adjustment value is calculated based on a preset algebraic relationship.

[0059] In addition to the above differences, the stiffness of the rolling mill is also a major factor affecting the roll gap horizontal pre-adjustment value. In order to be applicable to different rolling mills, the stand adjustment coefficient can be introduced, and the algebraic relationship between them can be obtained by using regression analysis of historical data, so as to obtain the final roll gap horizontal pre-adjustment value.

[0060] Step S104: Adjust the roll gap level according to the above-mentioned pre-adjusted level value.

[0061] The specific adjustment method is as follows: the absolute value of the obtained result is the adjustment parameter. Based on the above-mentioned preset algebraic relationship, if the result is negative, it indicates that the roller gap on the pressing operation side is being pressed; if it is positive, it indicates that the roller gap on the pressing drive side is being pressed, and adjustments are made according to the result.

[0062] Furthermore, the above-mentioned steps for calibrating the roll gap of the finishing mill also include:

[0063] The roll gap of the finishing mill is calibrated using the rolling force detected by the pressure head.

[0064] It should be noted that the roll gap calibration using pressure head detection is more accurate than the calibration using hydraulic pressure sensors.

[0065] Furthermore, before calculating the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, the above method also includes:

[0066] Record the rolling force data of the pressure head and hydraulic pressure sensor before each stand of the rolling mill is calibrated.

[0067] It should be noted that the data after calibration is mostly reset to zero. Therefore, this embodiment records the rolling force data of each stand pressure head and hydraulic pressure sensor one second before calibration is completed. This allows the design to be adapted to the needs of various rolling mills.

[0068] Furthermore, the steps described above for calculating the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor also include:

[0069] Calculate the first rolling force deviation dF between the upper pressure head and the hydraulic pressure sensor on the transmission side. DS ;

[0070] Calculate the second rolling force deviation dF between the pressure head and the hydraulic pressure sensor on the operating side. OS ;

[0071] The aforementioned difference is equal to the difference dF between the aforementioned first rolling force deviation and the aforementioned second rolling force deviation. DS -dF OS .

[0072] Substituting the difference into the predefined algebraic relation, it is expressed as:

[0073]

[0074] Where Level is the pre-adjustment value of the roll gap of the finishing mill stand, k is the stand adjustment coefficient, W is the stand stiffness (W=100 in this embodiment), and dF DS For the first rolling force deviation, dF OS This is the second rolling force deviation.

[0075] Furthermore, the step of adjusting the roll gap level according to the pre-adjusted level value further includes:

[0076] If the result obtained based on the above-mentioned preset algebraic relationship is negative, it indicates that the roller gap on the pressing operation side is being processed; if it is positive, it indicates that the roller gap on the pressing drive side is being processed.

[0077] It should be noted that the operation method is judged based on the positive or negative value of the result, while the numerical value of the operation is directly the absolute value of the result.

[0078] Furthermore, the above method also includes:

[0079] Based on historical data, regression analysis was used to obtain the algebraic relationship between the stiffness data, rolling force deviation, adjustment coefficient, and roll gap level pre-adjustment value of the above-mentioned frame.

[0080] It should be noted that regression analysis primarily uses historical data to analyze the direct relationship between multiple independent variables and the target variable, while this design uses a multiple regression model for analysis, such as... Figure 4 As shown, a regression model is established with the difference in total calibration force between the drive side and the operating side as the independent variable and the roll horizontal pre-adjustment value as the objective variable. Based on the corresponding relationship, calculation formulas are established for the difference and the corresponding roll horizontal pre-adjustment value. The use of this type of regression model is common knowledge and will not be elaborated upon here.

[0081] Based on the above explanation, this invention provides an example of calculating the pre-adjusted roll gap value after roll changing in the finishing mill of a 1580mm hot rolling production line of a steel enterprise:

[0082] First, the finishing mill is calibrated using pressure head calibration. The rolling force of stands F1, F2, F3 and F4 is calibrated to be 1500t, and the rolling force of stands F5, F6 and F7 is calibrated to be 1000t. During the calibration process, the deviation of the rolling force on both sides is adjusted to within 200KN, and the roll gap calibration of the finishing mill is completed.

[0083] Record the rolling force value F of the drive-side pressure head sensor one second before the calibration of each stand in the finishing mill is completed. LC_ds The rolling force value F of the transmission-side hydraulic pressure sensor PT_ds The rolling force value F of the operating side pressure head sensor. LC_os The rolling force value F of the operating side hydraulic pressure sensor PT_os Then substitute it into the difference calculation formula.

[0084]

[0085] The pre-adjusted roll gap value was obtained. Simultaneously, based on extensive experimental and historical data, a certain error exists between the calibrated force and the actual rolling force. Therefore, a multiplication factor K was used, with the adjustment factor for stands F1, F2, F3, and F4 being 0.8; and the adjustment factor for stands F5, F6, and F7 being 0.5. The calculated data is shown in the table below (unit: tons).

[0086] Rack F1 Rack F2 Rack F3 Rack F4 Rack F5 Rack F6 Rack F7 <![CDATA[F PT_ds ]]> 710 753 630 767 460 471 420 <![CDATA[F LC_ds ]]> 751 748 743 735 522 492 491 <![CDATA[F PT_os ]]> 790 767 860 723 570 491 526 <![CDATA[F LC_os ]]> 747 753 759 747 491 501 511 Level -0.67 -0.07 -1.71 0.45 -0.71 -0.06 -0.43

[0087] The absolute value of the obtained result is the adjustment parameter. If the result is negative, it indicates that the roller gap on the operation side is pressed; if it is positive, it indicates that the roller gap on the drive side is pressed, and adjustments are made according to the result. That is, the roller gaps on the operation side are pressed on frames F1, F2, F3, F5, F6, and F7; while the roller gap on the drive side is pressed on frame F4.

[0088] Based on the same inventive concept, embodiments of this application provide a roll gap level pre-adjustment value setting system for the first piece of steel during a finishing mill roll change, such as... Figure 2 As shown, it includes:

[0089] The calibration module is used to calibrate the roll gap of the finishing mill.

[0090] The difference calculation module is used to calculate the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, respectively.

[0091] The pre-adjustment value calculation module is used to calculate the roll gap horizontal pre-adjustment value based on a preset algebraic relationship using the mill's stiffness, the stand adjustment coefficient, and the above differences.

[0092] The adjustment module is used to adjust the roll gap level according to the pre-adjusted level value.

[0093] Based on the same inventive concept, such as Figure 3As shown, this embodiment provides an electronic device, characterized in that the electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements a method for setting the roll gap level pre-adjustment value of the first piece of steel for a finishing mill roll change.

[0094] Based on the same inventive concept, this embodiment provides a computer-readable storage medium storing a computer program, characterized in that, when executed by a processor, the program implements a method for setting the roll gap level pre-adjustment value for the first piece of steel in a finishing mill roll change.

[0095] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0096] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0097] In summary, this invention provides a method and system for setting the roll gap level pre-adjustment value for the first steel piece during roll change in a finishing mill. This includes using regression analysis based on historical data to obtain the algebraic relationship between the stand stiffness data, rolling force deviation, adjustment coefficient, and roll gap level pre-adjustment value. By utilizing the rolling forces detected by the pressure heads and hydraulic pressure sensors located on both sides of the mill (i.e., the operating side and the drive side) during calibration, and based on their interrelationships and differences, the adjustment direction and magnitude of the roll gap level for the first steel piece are determined. The roll gap level is then corrected, ensuring accurate use of the pre-adjustment value even when other conditions change, thereby preventing the given roll gap level pre-adjustment value from exceeding the required error.

[0098] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0099] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for setting the roll gap horizontal pre-adjustment value for the first piece of steel during a finishing mill roll change, characterized in that, The method includes: The roll gap of the finishing mill is calibrated; Calculate the first rolling force deviation between the upper pressure head and the hydraulic pressure sensor on the transmission side; Calculate the second rolling force deviation between the upper pressure head on the operating side and the hydraulic pressure sensor; Calculate the difference between the first rolling force deviation and the second rolling force deviation; Using the mill's rigidity, the stand adjustment coefficient, and the aforementioned difference, the roll gap horizontal pre-adjustment value is calculated based on a preset algebraic relationship. When the roll gap level pre-adjustment value is negative, the operation side roll gap is pressed according to the roll gap level pre-adjustment value; when the roll gap level pre-adjustment value is positive, the transmission side roll gap is pressed according to the roll gap level pre-adjustment value to adjust the roll gap level.

2. The method as described in claim 1, characterized in that, The step of calibrating the roll gap of the finishing mill also includes: The roll gap of the finishing mill is calibrated using the rolling force detected by the pressure head.

3. The method as described in claim 1, characterized in that, Before calculating the difference in rolling force deviation between the pressure head and the hydraulic pressure sensor on the drive side and the operating side respectively, the method further includes: Record the rolling force data of the pressure head and hydraulic pressure sensor before each stand of the rolling mill is calibrated.

4. The method as described in claim 1, characterized in that, The preset algebraic relations include: in, This is the pre-adjusted value for the horizontal gap of the finishing mill stand. This is the frame adjustment factor. For frame rigidity, The first rolling force deviation, This is the second rolling force deviation.

5. The method as described in claim 1, characterized in that, The method further includes: Based on historical data, regression analysis was used to obtain the algebraic relationship between the stiffness data of the frame, rolling force deviation, adjustment coefficient and roll gap level pre-adjustment value.

6. A roll gap level pre-adjustment value setting system for the first steel piece during a finishing mill roll change, implemented based on the method as described in claim 1, characterized in that, The system includes: The calibration module is used to calibrate the roll gap of the finishing mill. The difference calculation module is used to calculate the difference in rolling force deviation between the pressure heads on both sides of the rolling mill and the hydraulic pressure sensor, respectively. The pre-adjustment value calculation module is used to calculate the roll gap horizontal pre-adjustment value based on a preset algebraic relationship using the mill's stiffness, the stand adjustment coefficient, and the difference. The adjustment module is used to adjust the roll gap level according to the pre-adjusted level value.

7. An electronic device, characterized in that, The electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps corresponding to the method as described in any one of claims 1 to 5.

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