Dynamic pressure deviation control method for hot rolling coiling pinch roll

Abstract

The invention relates to a dynamic pressure deviation control method for a hot rolling coiling pinch roll, which comprises the following steps of: detecting the deviation degree of a center line of each coil of strip steel before coiling, determining a deviation correction value according to a detection result, determining a pressure correction value of the pinch roll according to the correction value, and coiling the strip steel according to the corrected pressure. According to the dynamic pressure deviation control method for the hot rolling coiling pinch roll, feedforward control over pressure is formed by detecting the deviation degree of the center line of the strip steel before coiling, and on the basis, the deviation degree of the center line of the strip steel is detected; alarm-based feedback compensation is established for the accuracy problem of feed-forward control caused by capability limitation of a transmission mechanism or inaccurate determination of center line skewness.

Description

Technical Field

[0001] The present invention belongs to the technical field of hot rolling coiling of strip steel, and particularly relates to a method for controlling the dynamic pressure deviation of pinch rolls in hot rolling coiling. Background Art

[0002] In the existing hot rolling coiling, collaborative operation is adopted between the pinch rolls and the coiler. The pinch rolls are used to traction and control the coiling material, thereby establishing the control of the strip steel. After the strip steel comes out of the finishing rolling section, it is sent to the coiler via the conveying roller table. Since it is necessary to ensure the completion of tension establishment in the initial stage of coiling, and maintaining the stability of tension is the top priority in the middle stage of coiling, the pressure control of the pinch rolls is usually carried out in the tail section of the strip steel. Because at this time, the finishing rolling has completed the steel throwing, forming a tension loss state, which will cause the strip steel to lose the constraint of one degree of freedom and is prone to the occurrence of center line deviation. This will cause the strip steel to impact the side guide plate, which may have an adverse effect on the strip shape, and at the same time, it will also form edge overflow.

[0003] In the prior art, for the problem of center line deviation at the tail of the strip steel, the solution measures adopted are: after the edge overflow signal appears on the human-machine interface, the on-site personnel manually adjust the pressure difference between the two sides of the pinch rolls. However, this adjustment has relatively large accuracy problems and randomness and hysteresis.

[0004] The invention application with the application number: CN201110001745.6 discloses a "method for controlling the pinch rolls of a hot rolling coiler", including the following steps: The first step: before the strip steel is bitten, the pinch rolls adopt position control; The second step: at the moment when the strip steel head is bitten, the pinch rolls adopt pressure control; The third step: after the strip steel winds around the reel and establishes tension, the pinch rolls adopt position control or pressure control; The fourth step: when the strip steel is thrown out from the front stand of the finishing rolling, the pinch rolls adopt pressure control.

[0005] The invention application with the application number: CN201410128278.7 discloses a "pressure leveling device and control method for hot rolling pinch rolls", including setting pressure judgment; according to the pressure judgment result, judging the pressure setting; setting the pressure leveling function; according to the pressure setting, setting the pressure that needs to be increased or decreased; according to the set pressure leveling function and the pressure that needs to be increased or decreased, the operating side pressure setting is increased or decreased on the basis of the original setting; according to the operating side pressure setting increased or decreased on the basis of the original setting, after recalculation, the pressure closed-loop control is executed to realize the pressure leveling function of the pinch rolls.

[0006] The invention application with the application number: CN201510427927.8 discloses "a method for reducing the tower shape at the head of a hot-rolled steel coil", including: after the secondary short-stroke control is completed, the follow-up mode of the side guide plate on the position control side is triggered, and the actual pressure value of the side guide plate on the pressure control side is used as the pressure setting value of the side guide plate on the position control side; when the actual pressure value of the side guide plate on the position control side reaches 80% or more of the pressure setting value, the follow-up mode of the side guide plate on the position control side is closed, and the side guide plate on the position control side is locked.

[0007] The invention application with the application number: CN201310087792.6 discloses "a control method for the coiler side guide plate to prevent the steel coil from being misaligned in the hot-rolling production line". By changing the programming in the coiler side guide plate control PLC and adding a force control link to the side guide plate control logic on the position control side, when the coiler mandrel is loaded, the side guide plate on the position control side transfers to the force control link to press against the strip steel, and then transfers to position control.

[0008] The invention application with the application number: CN202211194834.1 discloses "a control method for leveling the coiling pinch rolls according to the deviation of the center line at the tail of the finishing mill". It is judged by the deviation of the center line at the tail of the finishing mill. According to the judgment result of the deviation of the center line at the tail of the finishing mill, combined with the strip thickness, width, and hardness group, the pinch roll pressure or roll gap leveling amount is calculated. The pressure or roll gap of the working side pinch roll is automatically compensated and calculated through the program on the basis of the original control, increasing or decreasing the pressure or roll gap of the working side pinch roll to realize the automatic leveling function of the tail of the pinch roll. Summary of the Invention

[0009] The purpose of the present invention is to provide a pressure regulation scheme mainly based on feedforward control and supplemented by feedback control.

[0010] To achieve the above technical purposes, the present invention provides a dynamic pressure deviation control method for hot-rolling coiling pinch rolls, and its technical solution is as follows:

[0011] A dynamic pressure deviation control method for hot-rolling coiling pinch rolls,

[0012] Before coiling each coil of strip steel, a position detection in the width direction is established, and a deviation correction value is determined according to the detection result. According to the deviation correction value, a pressure correction value of the pinch roll is determined, and the strip steel is coiled according to the corrected pressure.

[0013] Further,

[0014] The "establishing a position detection in the width direction before coiling each coil of strip steel and determining a deviation correction value according to the detection result" is specifically carried out as follows:

[0015] S1: Divide the conveying roller section between the finishing mill section and the coiling section into a starting roller section, a middle roller section, and a tail roller section; establish multi-point data acquisition of the width direction position in the middle roller section and the tail roller section respectively and transmit it to L2;

[0016] S2: L2 calculates the average value based on the multi-point data collected in the middle roller section received; calculates the maximum and minimum values based on the multi-point data collected in the tail roller section received;

[0017] S3: Calculate the absolute value of the maximum and minimum values, and screen out the larger value among the absolute values;

[0018] S4: Subtract the average value calculated in step S2 from the larger value among the absolute values screened out, so as to complete the determination of the deviation correction value.

[0019] Further,

[0020] There are a total of 6 groups of conveying roller tables between the finishing mill section and the coiling section;

[0021] Divide the first conveying roller section into the starting roller section,

[0022] Divide the second, third, and fourth conveying roller sections into the middle roller section;

[0023] Divide the fifth and sixth conveying roller sections into the tail roller section;

[0024] The "establishing multi-point data of the width direction position in the middle roller section" herein is completed by collecting the width direction position of the target section at the end of the second conveying roller when the strip tail arrives, collecting the width direction position of the target section at the end of the third conveying roller when the strip tail arrives, and collecting the width direction position of the target section at the end of the fourth conveying roller when the strip tail arrives.

[0025] Further,

[0026] The data set formed by establishing multi-point data acquisition of the width direction position in the tail roller section is constituted by the following method: Trigger the acquisition when the strip tail arrives at the end of the middle roller section, and trigger the end of the acquisition according to the set time duration.

[0027] Further,

[0028] In L2, the correction reference value set according to the coil shape alarm type and the corresponding edge overflow gear and the correction reference table formed thereby are also entered;

[0029] When the coiling detector gives an alarm, first obtain the edge overflow value; secondly, determine the type of coiling alarm to which the current alarm belongs according to the contract number and destination of the coiled steel coil being wound; thirdly, determine the edge overflow gear to which it belongs based on the specific edge overflow value in combination with the correction reference table, thereby completing the determination of the correction reference value; finally, determine the deviation correction value for the subsequent strip steel according to the correction reference value in combination with the detection results of the position detection in the width direction established for each subsequent strip steel before coiling.

[0030] Furthermore,

[0031] Obtain one-dimensional data through Radon transform and determine the maximum value at the corresponding position as the edge overflow value.

[0032] Furthermore,

[0033] Set the coiling alarm types to two types: alarm for greater than 30mm and alarm for greater than 50mm;

[0034] For the type of alarm for greater than 30mm, set the following three edge overflow gears:

[0035] The first edge overflow gear: [30, 50)mm;

[0036] The second edge overflow gear: [50, 80)mm;

[0037] The third edge overflow gear: [80, 100]mm;

[0038] For the type of alarm for greater than 50mm, set the following three edge overflow gears:

[0039] The first edge overflow gear: [50, 80)mm;

[0040] The second edge overflow gear: [80, 100)mm;

[0041] The third edge overflow gear: ≥100mm.

[0042] Furthermore,

[0043] The so-called "determine the deviation correction value for the subsequent strip steel according to the correction reference value in combination with the detection results of the position detection in the width direction established for each subsequent strip steel before coiling" has the following specific steps:

[0044] First, set the gear of pressure adjustment according to the steel type and thickness; then, under each gear of pressure adjustment, set the deviation correction value gear; form a pressure distribution coefficient table and input it into L2;

[0045] Secondly, determine the pressure adjustment gear to which it belongs according to the steel type layer and thickness of the current steel coil,

[0046] Next, at the corresponding pressure adjustment gear position, determine the deviation correction gear position to which the deviation correction value belongs, thereby completing the determination of the final pressure correction value.

[0047] Further,

[0048] The "setting the pressure adjustment gear position according to the steel type and thickness" is specifically as follows:

[0049] Set carbon steel with a carbon content ≤ 0.6% to the first pressure adjustment gear position;

[0050] Set carbon steel with a carbon content > 0.6% to the second pressure adjustment gear position;

[0051] Set special steel types with a thickness ≤ 2.4 mm to the third pressure adjustment gear position;

[0052] Set special steel types with a thickness > 2.4 mm to the fourth pressure adjustment gear position.

[0053] Further,

[0054] At the first pressure adjustment gear position, the following deviation correction gear positions are formed:

[0055] X ≤ -100 mm;

[0056] X ∈ [-100, -80] mm;

[0057] X ∈ [-80, -60] mm;

[0058] X ∈ [-60, -40] mm;

[0059] X ∈ [-40, -20] mm;

[0060] X ∈ [-20, 20] mm;

[0061] X ∈ [20, 40] mm;

[0062] X ∈ [40, 60] mm;

[0063] X ∈ [60, 80] mm;

[0064] X ∈ [80, 100] mm;

[0065] X ≥ 100 mm;

[0066] Among the above,

[0067] X: Deviation correction value; the plus and minus signs respectively correspond to the working side and the drive side.

[0068] Further,

[0069] At the second pressure adjustment gear position, the following deviation correction gear positions are formed:

[0070] X ≤ -100 mm;

[0071] X ∈ [-100, -60] mm;

[0072] X ∈ [-60, -20] mm;

[0073] X ∈ [-20, 20] mm;

[0074] X ∈ [20, 60] mm;

[0075] X ∈ [60, 100] mm;

[0076] X ≥ 100 mm;

[0077] In the above,

[0078] X: Deviation correction value; the positive and negative signs correspond to the working side and the driving side respectively.

[0079] Furthermore,

[0080] At the third pressure adjustment gear, the following deviation correction gears are formed:

[0081] X ≤ -100 mm;

[0082] X ∈ [-100, -60] mm;

[0083] X ∈ [-60, -20] mm;

[0084] X ∈ [-20, 0] mm;

[0085] X ∈ [0, 20] mm;

[0086] X ∈ [20, 60] mm;

[0087] X ∈ [60, 100] mm;

[0088] X ≥ 100 mm;

[0089] In the above,

[0090] X: Deviation correction value; the positive and negative signs correspond to the working side and the driving side respectively.

[0091] Furthermore,

[0092] At the fourth pressure adjustment gear, the following deviation correction gears are formed:

[0093] X ≤ -100 mm;

[0094] X ∈ [-100, -60] mm;

[0095] X ∈ [-60, -20] mm;

[0096] X ∈ [-20, 0] mm;

[0097] X ∈ [0, 20] mm;

[0098] X ∈ [20, 60] mm;

[0099] X ∈ [60, 100] mm;

[0100] X ≥ 100 mm;

[0101] In the above,

[0102] X: Deviation correction value; the positive and negative signs correspond to the working side and the driving side respectively.

[0103] A dynamic pressure deviation control method for a hot-rolling coiling pinch roll in the present invention forms a feedforward control of pressure by detecting the deviation of the center line established before coiling the strip steel. On this basis, a feedback compensation based on alarm is established for the accuracy problem of the feedforward control caused by insufficient capacity of the transmission mechanism or inaccurate determination of the center line deviation. According to a dynamic pressure deviation control method for a hot-rolling coiling pinch roll, a regulation mainly based on feedforward control and supplemented by feedback control is finally formed. Description of the Drawings

[0104] Figure 1 It is a schematic diagram of the working principle of the present invention. Detailed Embodiment

[0105] To form a clearer understanding of this technical solution, the working principle and process of this technical solution are specifically described as follows.

[0106] Working Principle:

[0107] The background knowledge involved in this technical solution is as follows:

[0108] After the finishing section is the coiling section. A conveying roll section is arranged between the finishing section and the coiler, and this conveying roll section is composed of six groups of conveying roll tracks. A position sensor can be arranged on the side of the conveying roll to establish the detection of the position of the strip steel in the width direction. The process control computer L2 is used for data processing and issuing control instructions in the system.

[0109] For the understanding of the following description, it can be combined with Figure 1It is carried out. Different from the usual feedback control, this technical solution starts from feedforward control and establishes a pressure control scheme with feedforward control as the basic control. The type of pressure control targeted is bilateral pressure control, so the values appearing in the text will have positive and negative values, which are unified here as: the working side is positive and the driving side is negative. Based on this feedforward control, the basic idea is as follows: Before the target tail section of the strip steel reaches the coiler, the determination of the center line reference and the deviation degree are completed according to the position detection results, the deviation correction value is determined based on the two, and the pressure correction value of the pinch roll is determined according to the deviation correction value; when the target tail section of the strip steel reaches the coiler, the strip steel is coiled according to the corrected pressure. Since the center line reference is completed based on on-line detection and there is a skew problem itself, it will cause the pressure control adjustment based on feedforward adjustment to still alarm in the case of a large skew. For this situation, a correction reference table based on the coiling shape alarm type and the overflow edge gear is established, and the deviation correction value is compensated through the correction reference table, so as to complete the final determination of the deviation correction value. The corresponding finally determined deviation correction value is also carried out according to different pressure adjustment gears. That is: First, set the pressure adjustment gear according to the steel type and thickness; second, under each pressure adjustment gear, set the deviation correction value gear; form a pressure distribution coefficient table, and then determine the corresponding pressure correction value according to the finally determined deviation correction value.

[0110] To balance the calculation efficiency and data credibility, the determination of the center line reference above is completed by collecting the position in the width direction of the target section of the strip steel tail reaching the end position of the second conveying roller, collecting the position in the width direction of the target section of the strip steel tail reaching the end position of the third conveying roller, and collecting the position in the width direction of the target section of the strip steel tail reaching the end position of the fourth conveying roller, and then calculating the mean value of the data. To enable the feedforward control to be realized (that is, in time for regulation), the detection and determination of the deviation degree of the strip steel are set to start from the end position of the target section of the strip steel tail reaching the fourth conveying roller, and then the data collected within the set time length constitutes the data set used to determine the deviation degree. It should be noted here that the theoretical basis behind this is: Since the tension constraint disappears after the strip steel is ejected in the finishing section, the strip steel loses the constraint in one degree of freedom direction at this time, making it easy for the deviation from the center line to occur, and this occurrence will form an accumulative effect over time. Therefore, it has a high credibility to determine the center line reference in the initial stage and determine the deviation amount in the later stage respectively.

[0111] Working process:

[0112] First, the correction reference table and the pressure distribution coefficient table are respectively input into L2. The corresponding correction reference table and pressure distribution coefficient table are as follows. It should be noted that: the specific values of the correction reference values in the correction reference table given below are not unique, and here it is only for the purpose of example illustration; the special steel types in the steel type category in the pressure distribution coefficient table given below refer to steel types other than carbon steel:

[0113] Correction reference table

[0114] Roll-shaped alarm type Flashover gear Correction reference value (positive for the working side, negative for the driving side) Greater than 30mm 30mm - 50mm ±5mm Greater than 30mm 50mm - 80mm ±8mm Greater than 30mm 80mm - 100mm ±12mm Greater than 50mm 50mm - 80mm ±10mm Greater than 50mm 80mm - 100mm ±15mm Greater than 50mm ≥100mm ±18mm

[0115] Pressure distribution coefficient table

[0116]

[0117]

[0118] When the starting position of the target section at the tail of the strip reaches the end position of the second conveying roller, the position sensor is triggered to collect position signals and upload them to L2 to form the X1 value. When the starting position of the target section at the tail of the strip reaches the end position of the third conveying roller, the position sensor is triggered to collect position signals and upload them to L2 to form the X2 value. When the starting position of the target section at the tail of the strip reaches the end position of the fourth conveying roller, the position sensor is triggered to collect position signals and upload them to L2 to form the X3 value; when the end position of the target section at the tail of the strip reaches the end position of the fourth conveying roller, the position sensors in the section from the end of the fourth conveying roller to the coiling temperature measuring instrument (CT) are triggered to perform data collection for a continuous set duration to form a deviation dataset and upload it to L2. Then L2 calculates and determines the maximum and minimum values (i.e., the maximum value Xmax and the minimum value Xmin) in the deviation dataset. Then, in the case where the coiling shape detector does not issue an alarm, the deviation correction value is determined based on X1, X2, X3, Xmax, and Xmin, and combined with the steel type and thickness to complete the determination of the pressure correction value; in the case where the coiling shape detector issues an alarm, the edge overflow value is obtained from the data of the coiling shape detector. Then, first, the coiling shape alarm type to which the current alarm belongs is determined according to the contract number and destination of the coiled strip. Then, according to the specific edge overflow value and combined with the correction reference table, the edge overflow gear to which it belongs is determined, thereby completing the determination of the correction reference value. Finally, based on the correction reference value and combined with the deviation value in the width direction established before the coiling of each subsequent strip, the final pressure correction value is determined. Here, in the image processing part, if the scheme of processing two-dimensional images into one-dimensional data is adopted, from the perspectives of intuition, speed, and convenience, the Radon transform can be considered, but the processing of one-dimensionalizing the data is not limited to this processing method. The maximum value at the corresponding position in the one-dimensional data is selected as the specific edge overflow value.

[0119] The deviation correction value is determined based on X1, X2, X3, Xmax, and Xmin as follows:

[0120] First, perform the calculation of

[0121] X---Center line reference value, unit: mm;

[0122] X1---The position in the width direction when the starting position of the target section at the tail of the strip reaches the end position of the second conveying roller, unit: mm;

[0123] X2---The position in the width direction when the starting position of the target section at the tail of the strip reaches the end position of the third conveying roller, unit: mm;

[0124] X3---The position in the width direction when the starting position of the target section at the tail of the strip reaches the end position of the fourth conveying roller, unit: mm.

[0125] Then, through the following calculation, determine the larger value of the absolute values of the maximum and minimum values in the deviation measurement,

[0126] X m =|X max |-|X min |

[0127] If X m >0, then let X m =X max ; if X m <0, then let X m =X min .

[0128] Finally, based on the larger value of the absolute value and the average value, complete the calculation of the deviation amount as follows:

[0129] X x =X m -X

[0130] X x ---The deviation correction amount calculated through deviation detection, unit: mm.

[0131] When an alarm is issued, the corresponding deviation correction amount is determined according to the following formula:

[0132] X Y =X x +Y,

[0133] X x ---The deviation correction amount calculated through deviation detection, unit: mm;

[0134] Y---The correction reference value in the correction reference table, unit: mm;

[0135] X Y ---Deviation correction value in case of alarm, unit: mm.

Claims

1. A method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling, characterized in that: Before coiling each coil of strip steel, a position detection in the width direction is established, and the deviation correction value is determined according to the detection result. The pressure correction value of the pinch roll is determined according to the deviation correction value, and the strip steel is coiled according to the corrected pressure.

2. The method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling according to claim 1, characterized in that: The step of "establishing a position detection in the width direction before coiling each coil of strip steel and determining the deviation correction value according to the detection result" is as follows: S1: The conveying roll section between the finishing mill section and the coiling section is divided into a starting roll section, an intermediate roll section, and a tail roll section; multi-point data acquisition of the width direction position is established in the intermediate roll section and the tail roll section respectively and transmitted to L2; S2: L2 calculates the average value according to the multi-point data collected in the intermediate roll section received; calculates the maximum and minimum values according to the multi-point data collected in the tail roll section received; S3: Calculate the absolute value of the maximum and minimum values, and screen out the larger value among the absolute values; S4: Subtract the average value calculated in step S2 from the larger value among the absolute values screened out, so as to complete the determination of the deviation correction value.

3. The method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling according to claim 2, characterized in that: There are a total of 6 groups of conveying roller paths between the finishing mill section and the coiling section; The first conveying roll section is divided into the starting roll section, The second, third, and fourth conveying roll sections are divided into the intermediate roll section; The fifth and sixth conveying roll sections are divided into the tail roll section; The "multi-point data of the width direction position established in the intermediate roll section" is completed by collecting the width direction position of the target section at the end of the second conveying roll when the tail of the strip steel arrives, collecting the width direction position of the target section at the end of the third conveying roll when the tail of the strip steel arrives, and collecting the width direction position of the target section at the end of the fourth conveying roll when the tail of the strip steel arrives.

4. The method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling according to claim 2, characterized in that: The data set formed by establishing multi-point data acquisition of the width direction position in the tail roll section is constituted by the following method: triggering the acquisition when the tail of the strip steel reaches the end of the intermediate roll section and ending the acquisition according to the set duration.

5. The method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling according to claim 1, characterized in that: In L2, a correction reference value set according to the coiling shape alarm type and the corresponding overflow edge gear and the correction reference table formed thereby are also input; When the coiling shape detector issues an alarm, first obtain the overflow edge value; secondly, determine the coiling shape alarm type to which the current alarm belongs according to the contract number and destination of the current coiling steel coil; thirdly, determine the overflow edge gear to which it belongs according to the specific overflow edge value in combination with the correction reference table, so as to complete the determination of the correction reference value; finally, according to the correction reference value for the subsequent strip steel, in combination with the detection result of the position detection in the width direction established before coiling each subsequent coil of strip steel, determine the deviation correction value.

6. The method for controlling the dynamic pressure deviation of the pinch roll in hot rolling coiling according to claim 5, characterized in that: Set the coiled alarm types to two types: alarm for greater than 30 mm and alarm for greater than 50 mm; For the type of alarm for greater than 30 mm, set the following three levels of flash edge levels: The first level of flash edge level: [30, 50) mm; The second level of flash edge level: [50, 80) mm; The third level of flash edge level: [80, 100] mm; For the type of alarm for greater than 50 mm, set the following three levels of flash edge levels: The first level of flash edge level: [50, 80) mm; The second level of flash edge level: [80, 100) mm; The third level of flash edge level: ≥100 mm.

7. A method for controlling the dynamic pressure deviation of a hot rolling coiling pinch roll according to claim 5, characterized in that: For the subsequent strip steel "determine the deviation correction value according to the correction reference value and the detection result of establishing the position detection in the width direction before coiling each subsequent strip steel", the specific steps are as follows: First, set the pressure adjustment level according to the steel type and thickness; then, under each pressure adjustment level, set the deviation correction value level; form a pressure distribution coefficient table and input it into L2; Secondly, determine the pressure adjustment level to which the current steel coil belongs according to the steel type level and thickness of the current steel coil, Thirdly, under the corresponding pressure adjustment level, determine the deviation correction level to which the deviation correction value belongs, so as to complete the determination of the final pressure correction value.

8. A method for controlling the dynamic pressure deviation of a hot rolling coiling pinch roll according to claim 7, characterized in that: For the "setting the pressure adjustment level according to the steel type and thickness", specifically: Set the carbon steel with a carbon content ≤ 0.6% to the first pressure adjustment level; Set the carbon steel with a carbon content > 0.6% to the second pressure adjustment level; Set the special steel type with a thickness ≤ 2.4 mm to the third pressure adjustment level; Set the special steel type with a thickness > 2.4 mm to the fourth pressure adjustment level.

9. A method for controlling the dynamic pressure deviation of a hot rolling coiling pinch roll according to claim 8, characterized in that: At the first pressure adjustment level, the following deviation correction levels are formed: X ≤ -100 mm; X ∈ [-100, -80] mm; X ∈ [-80, -60] mm; X ∈ [-60, -40] mm; X ∈ [-40, -20] mm; X ∈ [-20, 20] mm; X ∈ [20, 40] mm; X ∈ [40, 60] mm; X ∈ [60, 80] mm; X ∈ [80, 100] mm; X ≥ 100 mm; Among the above, X: deviation correction value; the positive and negative signs respectively correspond to the working side and the driving side.

10. A dynamic pressure deviation control method for a hot rolling coiling pinch roll according to claim 8, characterized in that: At the second pressure adjustment level, the following deviation correction levels are formed: X ≤ -100 mm; X ∈ [-100, -60] mm; X ∈ [-60, -20] mm; X ∈ [-20, 20] mm; X ∈ [20, 60] mm; X ∈ [60, 100] mm; X ≥ 100 mm; Among the above, X: deviation correction value; the positive and negative signs respectively correspond to the working side and the driving side.

11. A dynamic pressure deviation control method for a hot rolling coiling pinch roll according to claim 8, characterized in that: At the third pressure adjustment level, the following deviation correction levels are formed: X ≤ -100 mm; X ∈ [-100, -60] mm; X ∈ [-60, -20] mm; X ∈ [-20, 0] mm; X ∈ [0, 20] mm; X ∈ [20, 60] mm; X ∈ [60, 100] mm; X ≥ 100 mm; Among the above, X: Deviation correction value; the positive and negative signs correspond to the working side and the driving side respectively.

12. A dynamic pressure deviation control method for a hot rolling coiling pinch roll according to claim 8, characterized in that: At the fourth pressure adjustment gear, the following deviation correction gears are formed: X ≤ -100 mm; X ∈ [-100, -60] mm; X ∈ [-60, -20] mm; X ∈ [-20, 0] mm; X ∈ [0, 20] mm; X ∈ [20, 60] mm; X ∈ [60, 100] mm; X ≥ 100 mm; Among the above, X: Deviation correction value; the positive and negative signs correspond to the working side and the driving side respectively.

13. A dynamic pressure deviation control method for a hot rolling coiling pinch roll according to claim 5, characterized in that: One-dimensional data is obtained through Radon transform, and the maximum value at the corresponding position is determined as the flash value.

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