A control method for the short stroke of the front guide of a finishing mill

Abstract

The present invention discloses a method for controlling the short stroke of the front guide of a finishing mill, comprising: after the front stand bites the steel, calculating the rolled-out length of the head of the strip in the front stand in real time; when the rolled-out length of the head of the strip in the front stand reaches the effective control range length of the front guide of the current stand, controlling the opening of the front guide of the current stand from the set opening to the head short stroke opening SG h After the frame bites the steel, the guide opening is controlled by SG h Execute to the short stroke opening of the body SG b After the previous rack is thrown, the guide opening is controlled by SG b The invention is beneficial to improving the threading stability of the strip head, reducing the center line deviation of the finished rolling exit strip, and has a certain positive significance for optimizing the coiling shape of the strip.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical automation control, and in particular to a control method for a short stroke of a leading guard of a finishing rolling mill. Background Art

[0002] In the field of metal rolling, the front of the rolling mill is generally designed with guide equipment that can be opened on both sides, or aligned, or asymmetrically controlled to ensure that the rolled material enters the rolling mill for rolling in a relatively aligned manner during the metal rolling process. However, due to various reasons, such as deviation of the incoming material, deviation of the rolling mill, etc., the strip gradually deviates from the rolling center line during the continuous thinning process, resulting in instability in the strip threading in the finishing mill, and the strip rolled out of the finishing mill deviates greatly from the center line, resulting in poor coil shape in the subsequent coiling, etc.

[0003] At present, there are several existing technologies for the design and control of guide equipment: 1. The patent application with application number CN205436627A proposes an online hot-rolled strip finishing entrance side guide device, which focuses on the improvement of the guide mechanical structure, thereby reducing the labor intensity of personnel maintenance. 2. The patent application with application number CN204276532A proposes a guide device that can automatically adjust the distance between guide plates, which installs a rolled piece width detection device on the frame to achieve the function of automatically adjusting the distance between guide plates. 3. The patent application with application number CN113042547A proposes a strip guiding method and side guide plate, which discloses a method for correcting the short-stroke opening of the front side guide plate of the coiler according to the center line deviation and width deviation of the strip at the outlet of the finishing mill.

[0004] In summary, there is currently a lack of short-stroke control methods for the opening of the front guide of the finishing mill in the field of metal rolling, and the existing technology cannot determine the timing of starting the opening of each guide in real time based on actual rolling data, thereby failing to achieve accurate control of the front guide of the finishing mill and failing to achieve better centering rolling effect of the finishing mill. Summary of the invention

[0005] The present invention provides a control method for the short stroke of the front guide of a finishing mill, so as to judge the timing of starting the opening of each guide in real time according to actual rolling data, thereby realizing accurate control of the front guide of the finishing mill, and further achieving a better centering rolling effect of the finishing mill.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for controlling a short stroke of a front guide of a finishing mill, comprising:

[0008] After the previous stand bites the steel, the rolled length of the strip head in the previous stand is calculated in real time;

[0009] When the rolled length of the strip head in the previous stand reaches the effective control range of the guide equipment in front of this stand, the opening of the guide in front of this stand is controlled from the set opening to the short stroke opening of the head SG h ;

[0010] After the frame bites the steel, the guide opening is controlled by SG h Execute to the short stroke opening of the body SG b ;

[0011] After the previous rack is thrown, the guide opening is controlled by SG b Execute to the short stroke opening of the tail.

[0012] Furthermore, after the previous stand bites the steel, the rolling length of the strip head in the previous stand is calculated in real time, including:

[0013] After the previous stand bites the steel, the rolled length of the strip head in the previous stand is calculated in real time based on the actual linear speed of the rolls of the previous stand and the forward slip coefficient.

[0014] Furthermore, the calculation formula for the rolled length of the strip head in the previous stand is:

[0015] S h =V f ×(1+f)×t

[0016] Among them, S h Indicates the rolled length of the strip head in the previous stand, V f It represents the actual linear speed of the roll of the previous stand, f represents the forward slip coefficient of the previous stand, and t represents the rolling time after the previous stand bites the steel.

[0017] Furthermore, the rolled-out length of the head of the strip in the previous stand is the distance from the head of the strip to the center line of the roll of the previous stand.

[0018] Furthermore, the effective control range length of the guide device is the distance from the guide device to the center line of the rolling mill roll of the previous stand.

[0019] Furthermore, the head short stroke opening SG h Make corresponding adjustments based on actual production needs.

[0020] Furthermore, the body short stroke opening SG b Make corresponding adjustments based on actual production needs.

[0021] Furthermore, the tail short stroke opening degree is adjusted accordingly according to actual production requirements.

[0022] The beneficial effects brought about by the technical solution provided by the present invention include at least:

[0023] The control method of the short stroke of the leading guard of the finishing mill provided by the present invention determines when to start the short stroke of the leading guard of the current frame by calculating the real-time position of the length of the head of the strip rolled out of the previous frame between the frames, thereby quickly aligning the metal incoming material of the rolling mill and making the center line deviation of the finished rolling strip smaller. The control method of the present invention is simple and easy to implement, can effectively ensure the threading stability during the rolling process of the finishing mill, and make the center line deviation of the finished rolling strip smaller, which has a certain positive significance for the good coil shape of the subsequent coiling head. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 It is an execution flow chart of a control method for a short stroke of a front guide of a finishing mill provided by an embodiment of the present invention;

[0026] Figure 2 It is a control principle diagram of a control method for a short stroke of a front guide of a finishing mill provided in an embodiment of the present invention.

[0027] Description of reference numerals:

[0028] 100, metal plate; 101, rolling center line; 102, center line of the previous stand roll;

[0029] 11. Support roller of the previous frame; 12. Working roller of the previous frame;

[0030] 21. Support roller of this frame; 22. Working roller of this frame. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0032] This embodiment provides a method for controlling the short stroke of the front guide of a finishing mill. The control principle of the method is as follows: Figure 2 As shown, during the metal rolling process, the metal sheet 100 passes through the support roller 11 and the working roller 12 of the previous stand along the rolling center line 101. At this time, the length S of the head of the metal sheet 100 passing through the center line 102 of the previous stand roll is calculated in real time. h , wait for S h The effective control range length S of the machine frame guide is reached a When the guide opening is set to SG sExecute to the head short stroke opening SG h When the metal sheet 100 passes through the support roller 21 and the working roller 22 of the frame, the guide opening is SG h Execute to the short stroke opening of the body SG b When the tail of the metal sheet 100 leaves the support roller 11 of the previous frame and the working roller 12 of the previous frame, the guide opening is changed from the short stroke opening of the main body SG b Execute to the tail short stroke opening SG t .

[0033] Specifically, the execution process of this method is as follows Figure 1 As shown, the following steps are included:

[0034] S1, after each finishing rolling stand guides the previous stand to bite the steel, the rolled length S of the strip head in the previous stand is calculated in real time according to the actual linear speed and forward slip coefficient of the roll of the previous stand. h , the formula is:

[0035] S h =V f ×(1+f)×t

[0036] Among them, V f is the actual linear speed of the roller of the previous stand during rolling, in m / s; f is the forward slip coefficient of the previous stand, which is used to calculate the running speed of the strip rolled out by the previous stand, V f and f are data set by the rolling process control system according to the current rolling situation, and t is the rolling time after the previous stand bites the steel, in seconds.

[0037] S2, when S h Reach the effective control range length S of the front guide equipment of this rack a When the guide head is started to travel short, the guide opening in front of the machine frame changes from the set opening SG s Execute to the head short stroke opening SG h ;

[0038] Among them, S a It is the length from the center line of the previous stand roll to the effective control range of the guide guard of this stand, in meters, SG s The preset opening of the rack guide, SG h The opening degree that needs to be controlled when starting the short stroke of the head is in mm. h It can be adjusted accordingly according to actual production needs.

[0039] S3, after the frame bites the steel, the guide body is started to short-stroke, and the guide opening is controlled by SG h Execute to the short stroke opening of the body SGb ;

[0040] Among them, SG b The opening degree that needs to be controlled when starting the short stroke of the main body, in mm, SG b It can be adjusted accordingly according to actual production needs.

[0041] S4, after the previous frame throws steel, start the short stroke of the guide tail, and control the guide opening degree by SG b Execute to the tail short stroke opening SG t ;

[0042] Among them, SG t The opening degree that needs to be controlled when starting the tail short stroke, in mm, SG t It can be adjusted accordingly according to actual production needs.

[0043] The implementation process of the method of the present invention is described below in conjunction with specific application examples.

[0044] In this application example, the number of finishing mill stands is 8. Taking this stand as stand 2 and the previous stand as stand 1 as an example, the operation is performed as follows:

[0045] (1) When the No. 1 finishing mill bites the steel, according to the real-time linear speed of the No. 1 mill roll of 1.13 m / s, the forward slip coefficient f is set to 0.08. At this time, the head speed of the No. 1 mill strip is calculated to be 1.2204 m / s. At this time, the length of the No. 1 mill strip S is obtained. h =1.2204×t;

[0046] (2) Effective control range length S of the guide guard of No. 2 rolling mill a Assuming it is 4.9m, when the strip length S rolled out by the No. 1 rolling mill is h Equal to the effective control range length S of the No. 2 rolling mill guide a The time taken is t = S a ÷1.2204, t=4.015 is calculated. At this time, when the No. 1 rolling mill bites the steel for 4.015s, the opening of the front guide of the No. 2 rolling mill is changed from the set opening of 1575mm to the short stroke opening of the head of 1525mm;

[0047] (3) After the No. 2 rolling mill bites the steel, the opening of the front guide of the No. 2 rolling mill is changed from the head opening of 1525mm to the main body short stroke opening of 1550mm;

[0048] (4) After the No. 1 rolling mill is finished, the opening of the front guide of the No. 2 rolling mill is changed from the main body opening of 1550mm to the tail short stroke opening of 1535mm.

[0049] Through the above application examples, it can be found that the control method of the short stroke of the front guide of the finishing mill of the present invention can realize the accurate control of the front guide of the finishing mill in actual production, thereby achieving a better centering rolling effect of the finishing mill.

[0050] In summary, the control method of this embodiment calculates the real-time position of the strip head entering the frame according to the steel biting signal of the previous frame of the guide, the linear speed of the roller, and the forward slip coefficient. When the strip head enters the range of the guide, the guide is quickly closed to the short stroke position of the head, so that the center enters the frame. After the frame bites the steel, the guide is quickly opened to the short stroke position of the main body, and remains unchanged during the rolling process until the previous frame throws the steel, and the guide is adjusted to the short stroke position of the tail according to the control needs. It is beneficial to improve the threading stability of the strip head and reduce the center line deviation of the strip at the finish rolling exit, which has certain positive significance for optimizing the coiling shape of the strip.

[0051] In addition, it should be noted that the present invention can be provided as a method, an apparatus or a computer program product. Therefore, the embodiments of the present invention can take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware. Moreover, the embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code.

[0052] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0053] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device, so that a series of operation steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable terminal device provide for implementing the process in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0054] It should also be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0055] Finally, it should be noted that the above is a preferred embodiment of the present invention. It should be pointed out that although the preferred embodiment of the present invention has been described, for those skilled in the art, once the basic creative concept of the present invention is known, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention. Therefore, the attached claims are intended to be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the embodiments of the present invention.

Claims

1. A method for controlling the short stroke of the front guide of a finishing mill, characterized in that: include: After the previous stand bites the steel, the rolled length of the strip head in the previous stand is calculated in real time; When the rolled length of the strip head in the previous stand reaches the effective control range of the guide equipment in front of this stand, the opening of the guide in front of this stand is controlled from the set opening to the short stroke opening of the head SG h ; After the frame bites the steel, the guide opening is controlled by SG h Execute to the short stroke opening of the body SG b ; After the previous rack is thrown, the guide opening is controlled by SG b Execute to the tail short stroke opening; After the previous stand bites the steel, the rolled length of the strip head on the previous stand is calculated in real time, including: After the previous stand bites the steel, the rolled length of the strip head in the previous stand is calculated in real time according to the actual linear speed of the rolls of the previous stand and the forward slip coefficient; The calculation formula for the rolled length of the strip head in the previous stand is: S h =V f ×(1+f)×t Among them, S h Indicates the rolled length of the strip head in the previous stand, V f It represents the actual linear speed of the roll of the previous stand, f represents the forward slip coefficient of the previous stand, and t represents the rolling time after the previous stand bites the steel.

2. The method for controlling the short stroke of the front guide of the finishing mill according to claim 1, characterized in that: The rolled length of the strip head in the previous stand is the distance from the strip head to the center line of the roll of the previous stand.

3. The method for controlling the short stroke of the front guide of the finishing mill according to claim 1, characterized in that: The effective control range length of the guide and guard equipment is the distance from the guide and guard equipment to the center line of the roller of the previous stand.

4. The method for controlling the short stroke of the front guide of the finishing mill according to claim 1, characterized in that: The head short stroke opening SG h Make corresponding adjustments based on actual production needs.

5. The method for controlling the short stroke of the front guide of the finishing mill according to claim 1, characterized in that: The short stroke opening of the main body SG b Make corresponding adjustments based on actual production needs.

6. The method for controlling the short stroke of the front guide of the finishing mill according to claim 1, characterized in that: The tail short stroke opening is adjusted accordingly according to actual production requirements.

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