A rolling mill control method and apparatus
By improving the threading method for finished passes and adjusting the starting rolling force, the longitudinal thickness accuracy problem of the 20-roll mill during the starting of finished passes was solved, achieving higher longitudinal thickness accuracy and steel coil yield, reducing the length of longitudinal thickness deviation, and improving the quality and yield of finished coils.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHOUGANG ZHIXIN QIAN AN ELECTROMAGNETIC MATERIALS CO LTD
- Filing Date
- 2023-03-06
- Publication Date
- 2026-05-19
AI Technical Summary
The longitudinal thickness accuracy of the 20-roll mill is low when starting the finished product pass, which leads to a decrease in the yield and a long length of the finished coil with longitudinal thickness deviation.
By improving the strip threading method for finished passes, adjusting the starting rolling force, optimizing the acceleration operation method, using a disc shear to cut the strip, using a thickness gauge to detect the thickness value, recording the reference value of the starting rolling force, and ensuring that the strip thickness is within the preset range by increasing the speed in small steps and adjusting the rolling force.
It improved the longitudinal thickness accuracy of finished products and the yield of steel coils, reduced the length of thickness deviation at the start of the machine, and improved the overall quality and yield of finished coils.
Smart Images
Figure CN116237375B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of steel rolling technology, and in particular to a rolling mill control method and equipment. Background Technology
[0002] As a single-stand reversible rolling mill, the 20-roll mill's reciprocating rolling production mode leads to frequent changes in the roll gap position across passes, resulting in significant thickness fluctuations during the start-up and tail-end stages of each pass. Before starting the finished pass, the 20-roll mill requires changing the work rolls. Due to changes in the work roll diameter and surface roughness, as well as factors such as low surface temperature and insufficient roll crown of the newly installed rolls, there is a significant deviation between the rolling force calculated by the system and the rolling force required for the strip to reach the target thickness. Relying solely on the system's AGC function to automatically adjust the rolling force to achieve the target thickness results in slow thickness attainment and requires rolling a long distance, leading to low longitudinal thickness accuracy of the entire strip coil. The portion of the strip with thickness exceeding the tolerance at start-up is cut off as scrap steel in downstream processes, further reducing the yield of that coil and increasing the cost per ton of steel.
[0003] Therefore, how to adopt effective methods to improve the longitudinal thickness accuracy of finished product passes and the yield of steel coils, and ensure the quality of strip steel, is an urgent technical problem to be solved. Summary of the Invention
[0004] The purpose of this application is to provide a rolling mill control method and equipment. This application solves the problem of low longitudinal thickness accuracy of strip steel. By improving the strip threading method of finished passes, adjusting the starting rolling force, and optimizing the acceleration operation method, this application improves the longitudinal thickness accuracy of finished passes and the yield of steel coils, and reduces the length of thickness deviation at the starting point.
[0005] Specifically, this application adopts the following technical solution:
[0006] According to one aspect of the embodiments of this application, a rolling mill control method is provided, the method being applied to a 20-roll rolling mill, the method comprising: after the strip is tensioned, controlling a disc shear on the exit side of the rolling mill to shear the strip along the width direction to a preset width, and guiding the strip in the sheared area to a guide roller on the exit side of the rolling mill; controlling the coiler to rotate so that the strip is automatically torn in the sheared area; before starting the finished pass, increasing the starting rolling force to the initial rolling force; after starting the finished pass, detecting the strip thickness value by a thickness gauge on the exit side of the rolling mill; when the strip thickness value is stable at a preset thickness value, recording the starting rolling force used to roll the strip as a reference value for the starting rolling force of subsequent strips of the same specification; after the strip thickness value is stable at the preset thickness value, controlling the rolling mill to increase the rolling speed to a first preset speed; when the absolute value of the difference between the strip thickness value and the preset thickness value is less than a preset threshold, controlling the rolling mill to accelerate to a second preset speed based on the first preset speed according to a preset speed increase rate.
[0007] In some embodiments of this application, based on the foregoing scheme, the method further includes: controlling the rolling mill to stop accelerating when the absolute value of the difference between the strip thickness value and the preset thickness value is greater than or equal to the preset threshold.
[0008] In some embodiments of this application, based on the aforementioned scheme, the preset speed-up range is 5mpm to 10mpm.
[0009] In some embodiments of this application, based on the aforementioned scheme, the first preset speed is 35mpm to 40mpm.
[0010] In some embodiments of this application, based on the foregoing scheme, the preset threshold is 4.
[0011] In some embodiments of this application, based on the foregoing scheme, the method further includes:
[0012] When the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, the mill is stopped and the starting rolling force is adjusted before restarting until the strip thickness value stabilizes at the preset thickness value.
[0013] In some embodiments of this application, based on the aforementioned scheme, when the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, controlling the rolling mill to stop and adjusting the starting rolling force includes: when the difference between the strip thickness value and the preset thickness value is continuously greater than 0, controlling the rolling mill to stop, and increasing the starting rolling force based on the initial rolling force according to a preset rolling force adjustment range; when the difference between the strip thickness value and the preset thickness value is continuously less than 0, controlling the rolling mill to stop, and decreasing the starting rolling force based on the initial rolling force according to a preset rolling force adjustment range.
[0014] In some embodiments of this application, based on the aforementioned scheme, the preset rolling force adjustment range is 5t to 10t.
[0015] In some embodiments of this application, based on the aforementioned scheme, when the starting rolling force is increased to the initial rolling force, the increased rolling force is 10t to 20t.
[0016] According to one aspect of the embodiments of this application, an electronic device is provided, the electronic device including one or more processors and one or more memories, the one or more memories storing at least one piece of program code, the at least one piece of program code being loaded by the one or more processors and executing the operations performed by the mill control method as described above.
[0017] As can be seen from the above technical solution, this application has at least the following advantages and positive effects:
[0018] The proposed solution can solve the problem of low longitudinal thickness accuracy of strip steel. The proposed solution improves the longitudinal thickness accuracy of finished strip and the yield of steel coils by improving the strip threading method of finished strip, controlling the starting rolling force, and optimizing the acceleration operation method, thereby reducing the length of thickness deviation at the starting point. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in this application, 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 from these drawings without creative effort.
[0020] Figure 1 A flowchart of a rolling mill control method according to one embodiment of this application is shown;
[0021] Figure 2 This illustration shows a simplified diagram of a disc shear cutting a strip of steel along its width direction to a predetermined width, according to one embodiment of this application.
[0022] Figure 3 A simplified diagram of a 20-roll mill apparatus according to one embodiment of this application is shown;
[0023] Figure 4 The thickness fluctuation curve of the finished product during the acceleration stage is shown in one embodiment of this application;
[0024] Figure 5 The thickness fluctuation curve of the finished product track during the starting stage is shown in one embodiment of this application;
[0025] Figure 6 A schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application is shown.
[0026] The accompanying diagrams and their labels are explained below:
[0027] 201—Mandrel, 202—Feed roller,
[0028] 203—Guide roller, 301—Left side spindle,
[0029] 302—Left guide roller, 303—Left shaper roller,
[0030] 304—Left-side wiping roller; 305—Rolling mill.
[0031] 306—Right-side wiping roller; 307—Right-side plate shaper roller.
[0032] 308—Right-side guide roller, 309—Right-side spindle. Detailed Implementation
[0033] 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.
[0034] 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.
[0035] 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.
[0036] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of these terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described.
[0037] In this application, in order to roll thinner strip steel, the diameter of the work roll should be minimized. However, a small diameter of the work roll will reduce the rigidity of the rolling mill. To resolve this contradiction, other rolls are needed to support the work roll. This invention uses a 20-roll mill to roll the strip steel in finished passes. The 20-roll system can be divided into upper and lower groups. Each group consists of 4 support rolls, 3 intermediate rolls, 2 intermediate rolls and 1 work roll. As a single-stand reversible mill, the 20-roll mill can perform reciprocating rolling production mode, that is, one side of the mill can be used as the rolling exit or the rolling entrance.
[0038] The implementation details of the technical solutions in the embodiments of this application are described in detail below:
[0039] Reference Figure 1 , Figure 1 This is a flowchart of a rolling mill control method in one embodiment of this application.
[0040] According to a typical embodiment of this application, a rolling mill control method is provided, the method being applied to a 20-roll rolling mill, the method comprising the following steps S1 to S3:
[0041] Step S1: After the strip is tensioned, the disc shear on the mill exit side is controlled to cut the strip along the width direction to a preset width, and the strip in the shearing area is guided to the guide roller on the mill exit side. The coiler is controlled to rotate so that the strip is automatically torn in the shearing area.
[0042] In this application, the 20-roll mill is a single-stand reversible mill, as shown in the reference. Figure 2 , Figure 2This is a simplified diagram illustrating how a disc shear in one embodiment of this application cuts a strip steel to a preset width along the width direction. Before rolling, the rolling mill needs to establish tension. During tension establishment, the strip steel is guided from the mill inlet side to the mill outlet side, and the head side of the strip steel is wound onto the mandrel 201 of the coiler at the mill outlet side, completing the strip steel tension establishment. After the strip steel tension establishment is completed, the disc shear at the mill outlet side is controlled to cut the strip steel to a preset width along the width direction (e.g., ...). Figure 2 (As shown at point A), the preset width can be half or 1 / 3 of the strip width, etc. After the disc shear is completed, the strip in the shearing area is guided to the guide roller 203 on the exit side of the mill through full-line linkage, the feed roller 202 on the exit side is pressed down, and the mandrel 201 of the coiler is controlled to rotate so that the strip is automatically torn in the shearing area. By improving the strip threading method of the finished product pass, the risk of personnel contact with the strip can be avoided. Since the strip is broken only after it is pressed down by the exit feed roller, the rolling center line does not shift, ensuring the symmetry of the starting plate shape of the finished product pass.
[0043] Step S2: Before starting the rolling mill for the finished product pass, increase the starting rolling force to the initial rolling force. After starting the rolling mill for the finished product pass, use a thickness gauge on the exit side of the mill to detect the strip thickness. When the strip thickness is stable at the preset thickness value, record the starting rolling force used to roll the strip as a reference value for the starting rolling force of subsequent strips of the same specification.
[0044] In this application, the finished strip pass is the last rolling process in which the strip is rolled into a finished product. Before starting the finished strip pass, the starting rolling force of the finished strip pass can be calculated by the main operating system. However, before starting the finished strip pass, the 20-roll mill needs to change the work rolls, which changes the roll diameter and the surface roughness of the rolls. In addition, the newly installed rolls have low surface temperature and insufficient roll body crown, among other factors. This causes a large deviation between the rolling force calculated by the system and the rolling force required for the strip to reach the target thickness. Therefore, before starting the finished strip pass, the starting rolling force needs to be increased to the initial rolling force based on the starting rolling force calculated by the main operating system. This ensures that the rolling force at the start of the mill meets the starting rolling force required to roll the strip, thereby guaranteeing the quality of the finished strip.
[0045] In this application, after the finished strip is started, the thickness of the strip can be detected by a thickness gauge installed on the exit side of the mill. When the thickness of the strip is stable at the preset thickness value, the starting rolling force used to roll the strip can be recorded as a reference value for the starting rolling force of subsequent strips of the same specification, providing data support for the rolling of subsequent strips and improving the production efficiency of strips.
[0046] Step S3: After the strip thickness value stabilizes at the preset thickness value, control the rolling mill to increase the rolling speed to a first preset speed. When the absolute value of the difference between the strip thickness value and the preset thickness value is less than a preset threshold, control the rolling mill to accelerate to a second preset speed based on the first preset speed according to a preset speed increase rate.
[0047] In this application, after the strip thickness value stabilizes at the preset thickness value, the rolling mill can be controlled to rapidly increase the rolling speed to a first preset speed, thereby achieving a rapid increase in the rolling mill speed to the first preset speed within a short period of time. When the absolute value of the difference between the strip thickness value and the preset thickness value is less than a preset threshold, the rolling mill can be controlled to accelerate to a second preset speed based on the first preset speed according to a preset acceleration rate. The second preset speed can be the maximum rolling speed that the rolling mill can achieve when rolling the strip, and its maximum speed can be 800 m / min.
[0048] In this application, reference is made to Figure 3 , Figure 3 This is a simplified diagram of a 20-roll mill apparatus according to one embodiment of this application. The 20-roll mill apparatus used in this application is as follows: Figure 3 From left to right, the components include: left mandrel 301, left guide roller 302, left shaper roller 303, left wiping roller 304, rolling mill 305, right wiping roller 306, right shaper roller 307, right guide roller 308, and right mandrel 309. Through the joint operation of the twenty-roll rolling mill and other rollers and equipment in the production line, a reciprocating rolling production mode can be realized.
[0049] In one embodiment of this application, the method further includes: controlling the rolling mill to stop accelerating when the absolute value of the difference between the strip thickness value and the preset thickness value is greater than or equal to the preset threshold.
[0050] In this application, when the absolute value of the difference between the strip thickness value and the preset thickness value is greater than or equal to the preset threshold, it indicates that the strip thickness value has a large fluctuation problem. Therefore, when the absolute value of the difference between the strip thickness value and the preset thickness value is greater than or equal to the preset threshold, it is necessary to control the mill to stop accelerating. This can effectively ensure that the longitudinal thickness of the strip fluctuates within the standard range during the starting and speed-up stage of the finished product pass, so as to ensure the quality of the strip.
[0051] In one embodiment of this application, the preset speed-up range can be 5 mpm to 10 mpm.
[0052] In one embodiment of this application, the first preset speed can be 35mpm to 40mpm.
[0053] In this application, after the strip thickness value stabilizes at the preset thickness value, the rolling mill can be controlled to rapidly increase the rolling speed to a first preset speed, which can be 35mpm to 40mpm. When the rolling mill speed increases to 35mpm to 40mpm, and the roll shifting condition is met, the strip shape is rapidly adjusted to ensure symmetry. After the rolling mill speed increases to 35mpm to 40mpm, a small-amplitude step-by-step speed increase mode is used to accelerate according to a preset speed increase range, which can be 5mpm to 10mpm. When accelerating according to the preset speed increase range, the thickness curve of the thickness gauge needs to be closely monitored (the thickness gauge display range can be adjusted to 4μm). Figure 4 As shown, Figure 4 This is a thickness fluctuation curve of the finished product during the acceleration stage in one embodiment of this application. Figure 4 When the thickness curve oscillates within ±4μm, the speed is accelerated; when it exceeds ±4μm, the speed is kept constant. By accelerating the speed multiple times with small amplitudes and keeping the speed constant when the thickness curve exceeds ±4μm, the longitudinal thickness of the strip can be effectively guaranteed to fluctuate within the standard range during the starting and speed-up stage of the finished product pass. The length of the strip with excessive thickness during the speed-up stage is reduced, the abnormal cutting loss in downstream processes is reduced, and the yield of the whole coil of steel is improved.
[0054] In this application, it should be noted that when using a small-amplitude step-by-step acceleration mode to accelerate according to the preset speed increase, it is necessary to stop adjusting the ASU button to prevent the roller system from vibrating due to frequent adjustment of the ASU action to support the roller rack, which would prevent the thickness on the exit side from entering quickly.
[0055] In this application, by adjusting the starting rolling force, after the strip thickness value stabilizes at the preset thickness value, the rolling mill is controlled to rapidly increase the rolling speed to a first preset speed (35mpm~40mpm), and then a small-amplitude step-up speed increase mode is adopted to accelerate according to the preset speed increase range (5mpm~10mpm), so that the thickness of the strip at the mill exit quickly reaches the preset thickness value. The longitudinal thickness accuracy of the whole coil strip is high. By adjusting the starting rolling force, the thickness deviation length during the starting stage of the finished pass can be effectively reduced, and the rolling force can be precisely adjusted to achieve the target thickness of the finished pass quickly reaching the preset thickness value. Through small-amplitude multiple accelerations and constant speed maintenance operations, the longitudinal thickness of the strip can be effectively guaranteed to fluctuate within the standard range during the starting speed increase stage of the finished pass. The thickness deviation length during the speed increase stage is reduced, the abnormal cutting loss in downstream processes is reduced, and the overall yield of the coil steel is improved.
[0056] In one embodiment of this application, the preset threshold can be 4.
[0057] In one embodiment of this application, the method further includes: when the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, controlling the mill to stop and adjusting the starting rolling force before restarting the mill until the strip thickness value stabilizes at the preset thickness value.
[0058] In this application, a thickness gauge installed on the exit side of the rolling mill is used to detect the strip thickness. The thickness gauge typically displays a curve reflecting the true strip thickness after 5-8 meters of rolling. Figure 5 As shown, Figure 5 The thickness fluctuation curve of the finished product pass during the starting stage displayed by the thickness gauge, when the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0 (i.e., in the... Figure 5 In the middle, the curve fluctuates continuously above or below the "0" line. At this time, the strip is in an ultra-thick or ultra-thin state. The mill can be stopped and the starting rolling force adjusted before restarting until the strip thickness is stabilized at the preset thickness value (i.e., at the desired thickness). Figure 5 The middle curve is located at the "0" line.
[0059] In one embodiment of this application, when the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, controlling the rolling mill to stop and adjusting the starting rolling force includes:
[0060] When the difference between the strip thickness value and the preset thickness value is continuously greater than 0, the rolling mill is stopped, and the starting rolling force is increased based on the initial rolling force according to the preset rolling force adjustment range.
[0061] When the difference between the strip thickness value and the preset thickness value is continuously less than 0, the rolling mill is stopped, and the starting rolling force is reduced based on the initial rolling force according to the preset rolling force adjustment range.
[0062] In this application, when the difference between the strip thickness value and the preset thickness value is continuously greater than 0, it indicates that the strip is in an over-thickness state. It is necessary to control the mill to stop and increase the starting rolling force according to the preset rolling force adjustment range, based on the initial rolling force, until the difference between the strip thickness value and the preset thickness value is no longer continuously greater than 0. This ensures that the starting rolling force used for the strip can roll the strip thickness to the preset thickness value, avoiding the problem of excessive strip thickness caused by insufficient starting rolling force.
[0063] In this application, when the difference between the strip thickness value and the preset thickness value is continuously less than 0, it indicates that the strip is in an ultra-thin state. It is necessary to control the mill to stop and reduce the starting rolling force according to the preset rolling force adjustment range, based on the initial rolling force, until the difference between the strip thickness value and the preset thickness value is no longer continuously less than 0. This ensures that the starting rolling force used for the strip can roll the strip thickness to the preset thickness value, avoiding the problem of ultra-thin strip thickness caused by excessive starting rolling force.
[0064] In this application, by adjusting the starting rolling force, the thickness deviation length during the starting stage of the finished product pass can be effectively reduced. By precisely adjusting the starting rolling force, the strip thickness value can be quickly brought into the preset thickness value in the finished product pass.
[0065] In one embodiment of this application, the preset rolling force adjustment range can be 5t to 10t.
[0066] In one embodiment of this application, when the starting rolling force is increased to the initial rolling force, the increased rolling force can be 10t to 20t.
[0067] In this application, before the finished strip is rolled, the starting rolling force needs to be manually increased to the initial rolling force based on the starting rolling force of the finished strip roll calculated by the main control system. The increased rolling force can be 10t to 20t. When the difference between the strip thickness value and the preset thickness value is consistently less than 0, it indicates that the strip is in an ultra-thin state, and the mill needs to be stopped. The starting rolling force is then reduced based on the initial rolling force according to the preset rolling force adjustment range (adjusted in units of 5t to 10t). Similarly, when the difference between the strip thickness value and the preset thickness value is consistently less than 0, it indicates that the strip is in an ultra-thin state, and the mill needs to be stopped. The starting rolling force is then reduced based on the initial rolling force according to the preset rolling force adjustment range (adjusted in units of 5t to 10t), where the preset rolling force adjustment range can be 5t to 10t.
[0068] like Figure 6As shown, the computer system 600 includes a Central Processing Unit (CPU) 601, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 602 or programs loaded from Storage Unit 608 into Random Access Memory (RAM) 603, such as performing the methods described in the above embodiments. The RAM 603 also stores various programs and data required for system operation. The CPU 601, ROM 602, and RAM 603 are interconnected via a bus 604. An Input / Output (I / O) interface 605 is also connected to the bus 604.
[0069] The following components are connected to I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 610 as needed so that computer programs read from it can be installed into storage section 608 as needed.
[0070] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 609, and / or installed from removable medium 611. When the computer program is executed by central processing unit (CPU) 601, it performs various functions defined in the system of this application.
[0071] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such transmitted data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.
[0072] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.
[0073] The units described in the embodiments of this application can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.
[0074] According to a typical embodiment of this application, an electronic device is also provided, the electronic device including one or more processors and one or more memories, the one or more memories storing at least one piece of program code, the at least one piece of program code being loaded by the one or more processors and executing the operations performed by the mill control method as described above.
[0075] As can be seen from the above technical solution, this application has at least the following advantages and positive effects:
[0076] Firstly, the proposed solution solves the problem of low longitudinal thickness accuracy of strip steel. This application improves the longitudinal thickness accuracy of finished strip and the yield of steel coils by improving the strip threading method of finished strip, controlling the starting rolling force, and optimizing the acceleration operation method, thereby reducing the length of thickness deviation at the starting point.
[0077] Secondly, by adopting the solution proposed in this application, through multiple small-amplitude accelerations and maintaining a constant speed when the thickness curve exceeds the ±4μm range, it is possible to effectively ensure that the longitudinal thickness of the strip steel fluctuates within the standard range during the starting and speed-up stage of the finished product track. The length of thickness deviation during the speed-up stage is reduced, the abnormal cutting loss in downstream processes is reduced, and the yield of the whole coil steel is improved.
[0078] Third, by adopting the scheme proposed in this application, the average monthly thickness qualification rate of finished coils increased from 99.44% to 99.69%, an increase of 0.25%; the length of the head thickness deviation of finished strip steel caused by the starting stage of the train was shortened from 5 meters to 3 meters, and the downstream process reduced strip steel cutting loss by 2 meters. Based on the finished coil weight of 18t, the yield rate was increased by 0.02%, achieving cost reduction and efficiency improvement.
[0079] Fourth, adopting the solution proposed in this application improves the longitudinal thickness accuracy of the finished product passes, ensures the stability of rolling, avoids products that do not meet market demand from entering the market, and improves product quality and market competitiveness.
[0080] Although this application has been described with reference to several typical embodiments, it should be understood that the terminology used is descriptive and exemplary, and not restrictive. Since this application can be embodied in many forms without departing from the spirit or substance of the application, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.
Claims
1. A rolling mill control method, characterized in that, The method is applied to a 20-roll mill, and the method includes: After the strip is tensioned, the disc shear on the exit side of the mill controls the strip to cut a preset width along the width direction, and guides the strip in the shearing area to the guide roller on the exit side of the mill. The coiler is controlled to rotate so that the strip is automatically torn in the shearing area. Before starting the rolling mill for the finished product pass, the starting rolling force is increased to the initial rolling force. After starting the rolling mill for the finished product pass, the strip thickness is measured by a thickness gauge on the exit side of the mill. When the strip thickness stabilizes at the preset thickness value, the starting rolling force used to roll the strip is recorded as a reference value for the starting rolling force of subsequent strips of the same specification. The increased rolling force is 10t to 20t. After the strip thickness value stabilizes at the preset thickness value, the rolling mill is controlled to increase the rolling speed to a first preset speed. When the absolute value of the difference between the strip thickness value and the preset thickness value is less than a preset threshold, the rolling mill is controlled to accelerate to a second preset speed based on the first preset speed according to a preset speed-increasing range. The preset speed-increasing range is 5mpm to 10mpm; the first preset speed is 35mpm to 40mpm; and the preset threshold is 4. When the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, the mill is stopped and the starting rolling force is adjusted before restarting until the strip thickness value is stable at the preset thickness value. When the difference between the strip thickness value and the preset thickness value is continuously greater than 0 or continuously less than 0, the rolling mill is stopped and the starting rolling force is adjusted, including: When the difference between the strip thickness value and the preset thickness value is continuously greater than 0, the rolling mill is stopped, and the starting rolling force is increased based on the initial rolling force according to the preset rolling force adjustment range. When the difference between the strip thickness value and the preset thickness value is continuously less than 0, the rolling mill is stopped, and the starting rolling force is reduced based on the initial rolling force according to the preset rolling force adjustment range; the preset rolling force adjustment range is 5t~10t.
2. The method according to claim 1, characterized in that, The method further includes: When the absolute value of the difference between the strip thickness value and the preset thickness value is greater than or equal to the preset threshold, the mill is controlled to stop accelerating.
3. An electronic device, characterized in that, The electronic device includes one or more processors and one or more memories, wherein at least one piece of program code is stored in the one or more memories, and the at least one piece of program code is loaded and executed by the one or more processors to perform the operation performed by the method as described in any one of claims 1 to 2.