A method and system for controlling tail leveling of finished rolled strip

Abstract

The present application provides a method and system for controlling the tail leveling of a finished rolled strip, the method comprising: obtaining the strip width, the current frame rolling force deviation locking value, the current frame real-time total rolling force, and the current frame operating side and transmission side real-time rolling force deviation values; inputting the strip width, the current frame rolling force deviation locking value, the current frame real-time total rolling force, and the current frame operating side and transmission side real-time rolling force deviation values ​​into a preset roll gap deviation calculation model to obtain the roll gap deviation setting value of the next frame; adjusting the roll gap of the corresponding frame operating side and transmission side according to the roll gap deviation setting value of the next frame to complete the roll gap leveling control of the strip tail. The present application can effectively avoid tail swinging and rolling accidents caused by tail deviation during the rolling process of finished thin-gauge strip, improve the rolling stability of the production line, and improve the quality control level of thin-gauge products.

Description

Technical Field

[0001] The present invention relates to the field of intelligent steel production applications, and in particular to a method and system for controlling tail leveling of a finished rolled strip. Background Art

[0002] When the hot rolling production line is rolling thin specifications, the tail of the finished strip is deviated and crushed due to the loss of tension at the tail of the strip when the upstream stand is throwing the steel, etc., causing scratches on the finishing rolling work roll or the crushed strip fragments entering the rolling mill, affecting the subsequent rolling stability and rolling safety. When the tail of the thin-gauge strip is swinging and crushing, the site needs to stop the rolling in time to check whether the surface of the working roll is damaged. If the work roll surface is damaged, it needs to be replaced in time to avoid roll mark quality defects on the surface of the subsequent production strip. The existing control system does not have an automatic leveling control method for the roll gap on both sides of the finishing rolling. It can only rely on the operator to adjust the single-side roll gap of the downstream stand in advance according to the actual deviation of the tail of the strip when throwing the steel on the upstream stand. There are often problems such as untimely manual adjustment or wrong adjustment direction of the roll gap deviation, resulting in many accidents of thin-gauge strip swinging and crushing, which seriously affects the rolling stability and strip product quality. Summary of the invention

[0003] In view of the above problems existing in the prior art, the present invention proposes a method and system for controlling the leveling of the tail of the finished rolled strip, which mainly solves the problem that the tail of the thin-gauge strip is not manually adjusted in time or the roll gap deviation is adjusted in the wrong direction, resulting in aggravated tail of the thin-gauge strip, affecting the smooth production of the production line and product quality control.

[0004] In order to achieve the above-mentioned purpose and other purposes, the technical solution adopted by the present invention is as follows.

[0005] The present application provides a method for controlling the tail leveling of a finished rolled strip, comprising:

[0006] Obtain the strip width, the current stand rolling force deviation lock value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values;

[0007] Input the strip width, the current stand rolling force deviation locking value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values ​​into a preset roll gap deviation calculation model to obtain a roll gap deviation setting value for the next stand;

[0008] The roll gaps on the operating side and the transmission side of the corresponding frame are adjusted according to the roll gap deviation setting value of the next frame, so as to complete the roll gap leveling control at the tail of the strip.

[0009] In one embodiment of the present application, before obtaining the strip width, the current stand rolling force deviation locking value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current stand, it also includes: starting the strip tail roll gap leveling control of the next stand according to the current stand throwing signal. In one embodiment of the present application, obtaining the rolling force deviation locking value of the current stand includes:

[0010] The average rolling force deviation between the operating side and the transmission side of the current frame during the period from the previous frame throwing steel to the current frame throwing steel is calculated, and the average rolling force deviation is used as the rolling force deviation locking value of the current frame.

[0011] In one embodiment of the present application, before starting the strip tail roll gap leveling control of the next stand according to the steel throwing signal of the current stand, it also includes: using the time point when the detector in front of the finishing descaling box detects the tail of the strip as the time point for the first stand to start the strip tail roll gap leveling control.

[0012] In one embodiment of the present application, the roll gap deviation calculation model is expressed as:

[0013]

[0014] Among them, ΔS D-O The roll gap deviation setting value for the next stand, ΔF D-O is the real-time rolling force deviation value between the current rack transmission side and the operating side; ΔF L is the rolling force deviation locking value of the current frame transmission side and operation side; F is the real-time total rolling force of the current frame; W is the strip width; K1 is the strip thickness width coefficient; K2 is the deformation resistance coefficient.

[0015] In one embodiment of the present application, before inputting the strip width, the current stand rolling force deviation locking value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values ​​into the preset roll gap deviation calculation model, it also includes:

[0016] A process parameter mapping table is constructed, in which a mapping relationship between strip steel specifications and strip steel thickness and width coefficients is recorded; wherein the strip steel specifications include: strip steel type, strip steel width, strip steel thickness, etc.

[0017] The strip steel thickness width coefficient corresponding to the current strip steel specification is obtained by searching the process parameter mapping table.

[0018] In one embodiment of the present application, the roll gaps on the operating side and the transmission side of the corresponding frame are adjusted according to the roll gap deviation setting value of the next frame, including:

[0019] When the real-time rolling force deviation value of the current frame is less than the rolling force deviation locking value of the current frame, the operating side roll gap of the next frame is pressed down, and the transmission side roll gap of the next frame is lifted up, so that the average roll gap deviation value of the operating side roll gap of the next frame and the transmission side roll gap is equal to the roll gap deviation setting value of the next frame.

[0020] When the real-time rolling force deviation value of the current frame is greater than or equal to the rolling force deviation locking value of the current frame, the operating side roll gap of the next frame is lifted, and the transmission side roll gap of the next frame is pressed down, so that the average roll gap deviation value of the operating side roll gap of the next frame and the transmission side roll gap is equal to the roll gap deviation setting value of the next frame.

[0021] The present application also provides a finishing strip tail leveling control system, comprising:

[0022] A data acquisition module is used to obtain the strip width, the current stand rolling force deviation locking value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values;

[0023] A roll gap deviation calculation module is used to input the strip width, the current stand rolling force deviation locking value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current stand into a preset roll gap deviation calculation model to obtain a roll gap deviation setting value for the next stand;

[0024] The leveling control module is used to adjust the roll gaps on the operating side and the transmission side of the corresponding frame according to the roll gap deviation setting value of the next frame, so as to complete the roll gap leveling control of the tail of the strip.

[0025] As described above, the present invention provides a method and system for controlling the tail leveling of a finished strip, which have the following beneficial effects.

[0026] The present application obtains the strip width, the current frame rolling force deviation locking value, the real-time total rolling force of the current frame, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current frame; inputs the strip width, the current frame rolling force deviation locking value, the real-time total rolling force of the current frame, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current frame into the preset roll gap deviation calculation model to obtain the roll gap deviation setting value of the next frame; adjusts the roll gap of the corresponding frame operating side and the transmission side according to the roll gap deviation setting value of the next frame to complete the roll gap leveling control of the tail of the strip. By automatically leveling the roll gap deviation on both sides of the next frame, the strip tail is effectively avoided from running off and rolling due to the loss of tension of the strip tail when the upstream frame throws the steel during the rolling process of thin-gauge strip, and the strip tail is avoided from running off and rolling due to the operator's manual adjustment of the roll gap deviation in a timely manner or in the wrong direction, thereby improving the rolling stability of the production line and the product quality of the thin-gauge strip tail. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of a finishing rolling tail leveling control method in one embodiment of the present application.

[0028] Figure 2 Schematic diagram of the process parameter mapping corresponding to the width and thickness coefficients in one embodiment of the present application.

[0029] Figure 3 This is a limiting mapping table of the leveling output of the roll gap deviation calculation model in one embodiment of the present application.

[0030] Figure 4 This is a module diagram of a finishing tail leveling control system in one embodiment of the present application. DETAILED DESCRIPTION

[0031] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components during real-time implementation. During real-time implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0033] The main problems of existing control technology are as follows:

[0034] 1. The existing control technology does not have an automatic leveling control method for the tail of the finishing mill. It can only rely on the operator to make manual adjustments based on the actual deviation of the tail of the strip when the previous stand is throwing steel. It is often the case that the operator fails to adjust the deviation of the roll gap on both sides in time or adjusts the direction in the wrong way, resulting in aggravated deviation and rolling.

[0035] 2. When rolling thin-gauge strip steel, the operator is required to monitor the tail deviation of each strip in time and adjust the roller gap deviation on both sides of the frame in time. The labor intensity of the operator is high and the operation is repetitive.

[0036] 3. The tail of thin-gauge strip steel may cause scratches on the finishing rolling rolls or the broken strip steel fragments may enter the rolling mill, which will seriously affect the subsequent rolling stability and rolling safety.

[0037] In view of the problems existing in the above existing control technologies, the present application provides a method for controlling the tail leveling of a finished rolled strip. The method of the present application is described in detail below in conjunction with specific embodiments.

[0038] See also Figure 1 , Figure 1 The figure is a flow chart of a method for controlling the leveling of the tail of a finished steel strip in one embodiment of the present application. The method for controlling the leveling of the tail of a finished steel strip in one embodiment of the present application comprises the following steps:

[0039] Step S100, obtaining the strip width, the current frame rolling force deviation locking value, the current frame real-time total rolling force and the current frame operating side and transmission side real-time rolling force deviation values.

[0040] In one embodiment, obtaining the current stand rolling force deviation locking value includes:

[0041] The average rolling force deviation between the operating side and the transmission side of the current frame during the period from the previous frame throwing steel to the current frame throwing steel is calculated, and the average rolling force deviation is used as the rolling force deviation locking value of the current frame.

[0042] In one embodiment, the hot rolling production line is usually equipped with 7 finishing stands, and the average rolling force deviation ΔF between the transmission side and the operating side during the period from the F(i-2) stand to the F(i-1) stand can be pre-locked. L When the F(i-1) frame is throwing steel, the F(i) frame starts to automatically adjust the roll gap deviation on both sides, where the average rolling force deviation ΔF L That is the rolling force deviation locking value of the finishing mill stand F(i-1).

[0043] In one embodiment, the strip tail roll gap leveling control of the next stand can be started according to the steel throwing signal of the current stand.

[0044] In one embodiment, the time point when the detector in front of the finishing descaling box detects the tail of the strip is used as the time point for the first stand to start the roll gap leveling control of the tail of the strip. Specifically, the hot metal detector can be used to detect whether the tail of the strip leaves the detection position. For the first stand F1 of finishing rolling, since the F1 stand has no stable control timing signal, the F1 stand uses the heat detection signal HMD406 in front of the finishing descaling box as the starting time point for leveling. After starting the roll gap leveling control, the strip width, the current stand rolling force deviation locking value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current stand can be obtained.

[0045] Step S101, input the strip width, the current frame rolling force deviation locking value, the real-time total rolling force of the current frame, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current frame into a preset roll gap deviation calculation model to obtain a roll gap deviation setting value for the next frame.

[0046] In one embodiment, the variation process of the rolling force deviation on both sides of each finishing rolling stand during the rolling process of thin-gauge strip steel is analyzed and combined with rolling experience, a calculation model for automatic correction of the roll gap at the tail of the strip steel (i.e., a roll gap deviation calculation model) can be constructed. The calculation model can be expressed as:

[0047]

[0048] Among them, ΔS D-O The roll gap deviation setting value for the next stand, ΔF D-O is the real-time rolling force deviation value between the current rack transmission side and the operating side; ΔF L is the rolling force deviation lock value of the current frame transmission side and operation side; F is the real-time total rolling force of the current frame; W is the strip width; K1 is the strip thickness width coefficient; K2 is the deformation resistance coefficient. The deformation resistance coefficient K2 is automatically obtained according to the preset calculation value of the finishing rolling.

[0049] In one embodiment, before inputting the strip width, the current stand rolling force deviation locking value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values ​​into the preset roll gap deviation calculation model, the process further includes:

[0050] Constructing a process parameter mapping table, wherein the process parameter mapping table records a mapping relationship between strip steel specifications and strip steel thickness width coefficients;

[0051] The strip steel thickness width coefficient corresponding to the current strip steel specification is obtained by searching the process parameter mapping table.

[0052] See also Figure 2 , Figure 2 This is a schematic diagram of the process parameter mapping table corresponding to the width thickness coefficient in an embodiment of the present application. In order to adjust the adjustment coefficient K1 in stages according to the thickness and width of the strip, the K1 coefficient is placed on the process control computer and adjusted through the process parameter mapping table. Figure 2 The width thickness coefficient values ​​corresponding to the F1-F7 frames with different thickness grades.

[0053] See also Figure 3 , Figure 3This is a limit mapping table of the leveling output of the roll gap deviation calculation model in one embodiment of the present application. The limit value of the roll gap deviation setting value can be placed on the process control computer, and the limit adjustment can be performed through the process parameter mapping table. The roll gap deviation leveling limit value can be adjusted according to the actual control situation, and there is no restriction here.

[0054] Step S102, adjusting the roll gaps on the operating side and the transmission side of the corresponding frame according to the roll gap deviation setting value of the next frame, and completing the roll gap leveling control at the tail end of the strip.

[0055] In one embodiment, adjusting the roll gaps on the operating side and the transmission side of the corresponding frame according to the roll gap deviation setting value of the next frame includes:

[0056] When the real-time rolling force deviation value of the current frame is less than the rolling force deviation locking value of the current frame, the operating side roll gap of the next frame is pressed down, and the transmission side roll gap of the next frame is lifted up, so that the average roll gap deviation value of the operating side roll gap of the next frame and the transmission side roll gap is equal to the roll gap deviation setting value of the next frame.

[0057] When the real-time rolling force deviation value of the current frame is greater than or equal to the rolling force deviation locking value of the current frame, the operating side roll gap of the next frame is lifted, and the transmission side roll gap of the next frame is pressed down, so that the average roll gap deviation value of the operating side roll gap of the next frame and the transmission side roll gap is equal to the roll gap deviation setting value of the next frame.

[0058] Specifically, after the previous stand throws steel, if the actual rolling force deviation ΔF D-O Deviation ΔF relative to locking rolling force L When the actual rolling force deviation increases (the actual rolling force deviation is greater than the locked rolling force deviation), the roll gap deviation target value is set according to the automatic leveling calculation, the roll gap on the operating side of the next stand is automatically pressed down, and the roll gap on the transmission side of the next stand is raised. After the current stand is cast, the roll gap deviation on both sides of the next stand automatically reaches the roll gap deviation target value set by leveling; if the actual rolling force deviation ΔF D-O Deviation ΔF relative to locking rolling force L When it decreases (the actual rolling force deviation is less than the locked rolling force deviation), the roll gap deviation target value is set according to the automatic leveling calculation, the roll gap on the operating side of the next frame is automatically raised, and the roll gap on the transmission side of the next frame is pressed down. After the current frame throws steel, the roll gap deviation on both sides of the next frame automatically reaches the leveling set roll gap deviation target value to reduce the strip tail deviation caused by the loss of tension when the upstream frame throws steel. At the same time, the roll gap deviation leveling control function can be selectively used for different frames to meet different production needs on site.

[0059] Based on the above technical scheme, the present application has a significant inhibitory effect on the deviation and crushing of the tail of thin-gauge strip by automatically leveling the roll gap at the tail of the finished strip, and the accidents of tail swinging and crushing of thin-gauge strip are reduced by more than 85%, thereby greatly improving the rolling stability of thin-gauge strip; effectively reducing the frequent occurrence of tail swinging and crushing accidents caused by the manual adjustment of the roll gap deviation on both sides of thin-gauge strip in a timely manner or in the wrong direction; reducing the labor intensity of the operator's frequent adjustment of the roll gap deviation at the tail of thin-gauge strip; reducing a large amount of unplanned roll change stop time caused by tail swinging and crushing of thin-gauge strip, thereby improving rolling stability and safety.

[0060] See also Figure 4 This embodiment also provides a tail leveling control system for a finished steel strip, which is used to execute the tail leveling control method for a finished steel strip described in the above method embodiment. Since the technical principle of the system embodiment is similar to that of the above method embodiment, the same technical details will not be repeated.

[0061] In one embodiment, a control system for leveling the tail of a finished rolled strip includes: a data acquisition module 10, which is used to obtain the strip width, the current frame rolling force deviation locking value, the real-time total rolling force of the current frame, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current frame; a roll gap deviation calculation module 11, which is used to input the strip width, the current frame rolling force deviation locking value, the real-time total rolling force of the current frame, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current frame into a preset roll gap deviation calculation model to obtain a roll gap deviation setting value for the next frame; a leveling control module 12, which is used to adjust the roll gaps of the operating side and the transmission side of the corresponding frame according to the roll gap deviation setting value of the next frame to complete the roll gap leveling control of the tail of the strip.

[0062] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for controlling the tail leveling of a finished strip, characterized in that: include: Obtain the strip width, the current stand rolling force deviation lock value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values; Obtaining the rolling force deviation locking value of the current stand, including: calculating the average rolling force deviation of the current stand between the previous stand and the current stand during the period from steel throwing to steel throwing, and taking the average rolling force deviation as the rolling force deviation locking value of the current stand; The strip width, the current stand rolling force deviation locking value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the current stand operation side and transmission side are input into a preset roll gap deviation calculation model to obtain the roll gap deviation setting value of the next stand; the roll gap deviation calculation model is expressed as: Among them, ΔS D-O The roll gap deviation setting value for the next stand, ΔF D-O is the real-time rolling force deviation value between the current rack transmission side and the operating side; ΔF L is the rolling force deviation locking value of the current frame transmission side and operation side; F is the real-time total rolling force of the current frame; W is the strip width; K1 is the strip thickness width coefficient; K2 is the deformation resistance coefficient; The roll gaps on the operating side and the transmission side of the corresponding frame are adjusted according to the roll gap deviation setting value of the next frame to complete the roll gap leveling control of the tail of the strip; the roll gaps on the operating side and the transmission side of the corresponding frame are adjusted according to the roll gap deviation setting value of the next frame, including: when the real-time rolling force deviation value of the current frame is less than the rolling force deviation locking value of the current frame, the roll gap on the operating side of the next frame is pressed down, and the roll gap on the transmission side of the next frame is lifted up, so that the average roll gap deviation value between the roll gap on the operating side of the next frame and the roll gap on the transmission side is equal to the roll gap deviation setting value of the next frame; when the real-time rolling force deviation value of the current frame is greater than or equal to the rolling force deviation locking value of the current frame, the roll gap on the operating side of the next frame is lifted up, and the roll gap on the transmission side of the next frame is pressed down, so that the average roll gap deviation value between the roll gap on the operating side of the next frame and the roll gap on the transmission side is equal to the roll gap deviation setting value of the next frame.

2. The method for controlling the leveling of the tail of the finished strip according to claim 1, characterized in that: Before obtaining the strip width, the current stand rolling force deviation lock value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the current stand operating side and transmission side, it also includes: starting the strip tail roll gap leveling control of the next stand according to the current stand throwing signal.

3. The method for controlling the leveling of the tail of the finished strip according to claim 2, characterized in that: Before starting the strip tail roll gap leveling control of the next stand according to the current stand throwing signal, it also includes: The time point when the detector in front of the finishing descaling box detects the tail of the strip is used as the time point for the first stand to start the roll gap leveling control of the tail of the strip.

4. The method for controlling the leveling of the tail of the finished strip according to claim 1, characterized in that: Before inputting the strip steel width, the current stand rolling force deviation locking value, the current stand real-time total rolling force, and the current stand operating side and transmission side real-time rolling force deviation values ​​into the preset roll gap deviation calculation model, the method further includes: Constructing a process parameter mapping table, wherein the process parameter mapping table records a mapping relationship between strip steel specifications and strip steel thickness width coefficients; The strip steel thickness width coefficient corresponding to the current strip steel specification is obtained by searching the process parameter mapping table.

5. A finishing strip tail leveling control system for executing the finishing strip tail leveling control method according to any one of claims 1 to 4, characterized in that: include: A data acquisition module is used to obtain the strip width, the rolling force deviation locking value of the current stand, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current stand; A roll gap deviation calculation module is used to input the strip width, the current stand rolling force deviation locking value, the real-time total rolling force of the current stand, and the real-time rolling force deviation values ​​of the operating side and the transmission side of the current stand into a preset roll gap deviation calculation model to obtain a roll gap deviation setting value for the next stand; The leveling control module is used to adjust the roll gaps on the operating side and the transmission side of the corresponding frame according to the roll gap deviation setting value of the next frame, so as to complete the roll gap leveling control of the tail of the strip.

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