Automatic control method for protection of coiling pinch roll surface based on roll break identification

Abstract

The present invention discloses an automatic control method for protecting the roll surface of a coiling pinch roll based on rolling fracture identification, comprising the following steps: 1. an industrial camera (9) is arranged above the outlet of a finishing rolling F7 frame (7) and connected to a pinch roll (12) via a pinch roll control component; 2. a pinch roll gap opening is set to H1 when the head of a strip (20) exits a finishing rolling F3 frame (3); 3. when the head of the strip exits the finishing rolling F7 frame, the industrial camera takes an image of the head of the strip; 4. abnormal rolling of the head of the strip If the strip is broken, execute step 5, otherwise keep the roll gap opening H1 and go to step 6; 5. Adjust the roll gap opening to H2; 6. Adjust the roll gap opening to H3 after the head of the strip passes through the pinch rollers; 7. After the tail of the strip leaves the finishing rolling F7 stand, the industrial camera takes an image of the tail of the strip; 8. If the tail of the strip is abnormally broken, execute step 9, otherwise keep the roll gap opening H3 and go to step 10; 9. Adjust the roll gap opening to H4; 10. Adjust the roll gap opening to H5 after the tail of the strip passes through the pinch rollers.

Description

Technical Field

[0001] The invention relates to a hot-rolled strip steel production method, in particular to an automatic control method for protecting the roll surface of a coiling and pinching roll based on rolling fracture identification. Background Art

[0002] In the hot rolling coiling control process, pinch roll control is a very important link, which is directly related to the surface quality and coil quality of the strip. At present, the setting control of the pinch roll gap position is mainly based on the control system based on position sensors and automatic control based on pressure detection. Please refer to the attached Figure 1 The strip 20 passes through the finishing rolling F1 frame 1, the finishing rolling F2 frame 2, the finishing rolling F3 frame 3, the finishing rolling F4 frame 4, the finishing rolling F5 frame 5, the finishing rolling F6 frame 6, the finishing rolling F7 frame 7, the side guide plate 11, and the pinch roller 12 in sequence, and is then coiled by the first coiler 16. In the prior art, the control process of the pinch roller 12 of the first coiler 16 is as follows: (1) After the head of the strip 20 exits the finishing rolling F3 frame 3, the roll gap opening of the pinch roller 12 is set to H1 through the position control mode; (2) When the head of the strip 20 reaches the pinch roller 12, the roll gap control of the pinch roller 12 is converted from position control to pressure detection automatic control. According to the fluctuation of the impact pressure formed by the head of the strip 20 on the pinch roller 12, the pinch roller 12 is opened or closed according to the preset pressure-roll gap relationship. (3) When the tail of the steel strip 20 reaches X meters in front of the pinch roller 12, the roller gap control of the pinch roller 12 is switched from pressure detection automatic control to position control.

[0003] During the process of the head or tail of the steel strip 20 entering the pinch roller 12, if the operator observes with the naked eye that the head or tail of the steel strip 20 is punctured, broken or other abnormalities, it is necessary to manually intervene in the roller gap of the pinch roller 12 before the head or tail of the steel strip 20 is about to exit the side guide plate 11 but before reaching the pinch roller 12, so as to avoid the abnormal area of ​​the head or tail of the steel strip 20 and avoid damage to the roller surface of the pinch roller 12. Due to the high speed of the steel strip 20, the accuracy and real-time observation of the operator through the naked eye and the timeliness and precision of the manual intervention action are not matched with the actual production speed, and the accuracy of the roller gap opening adjustment is low, and it is impossible to completely avoid damage to the roller surface of the pinch roller 12 and the auxiliary winding roller, and it is even more impossible to ensure the control accuracy of the hand action and the distance between the abnormal area of ​​the head and tail of the steel strip 20 and the pinch roller 12. In order to restore the roller surface of the pinch roller 12 and the auxiliary winding roller, it is necessary to stop the machine and grind the roller surface of the pinch roller 12 clean, which has a great impact on the production progress.

[0004] Chinese invention patent ZL201410128278.7 discloses a control method for pressure leveling of hot rolling coiling pinch rollers, which includes: setting pressure judgment; judging pressure setting according to pressure judgment result; setting pressure leveling function; setting pressure to be increased or decreased according to pressure setting; setting pressure on the operating side to be increased or decreased on the basis of the original setting according to the set pressure leveling function and the pressure to be increased or decreased; setting pressure on the operating side to be increased or decreased on the basis of the original setting according to the pressure setting on the operating side, and performing pressure closed-loop control after recalculation to realize the pinch roller pressure leveling function. This method controls the pinch roller gap based on pressure, but cannot avoid abnormal areas such as strip puncture, resulting in damage to the pinch roller surface after the abnormal area of ​​strip puncture contacts with the pinch roller. Summary of the invention

[0005] The purpose of the present invention is to provide an automatic control method for protecting the roll surface of the coiling pinch roller based on puncture identification, which can accurately adjust the roll gap opening of the pinch roller according to the puncture abnormalities at the head and tail of the strip, thereby improving the damage to the roll surface of the pinch roller and the surface quality of the strip.

[0006] The present invention is achieved in that:

[0007] An automatic control method for protecting the roll surface of a coiling pinch roll based on roll break identification comprises the following steps:

[0008] Step 1: An industrial camera is arranged above the outlet of the finishing rolling F7 stand so that the shooting area of ​​the industrial camera can cover the outlet opening range of the finishing rolling F7 stand, and the industrial camera is connected to the pinch roller through the pinch roller control assembly;

[0009] Step 2: When the head of the strip exits the finishing rolling F3 stand, the pinch roll control assembly sets the roll gap opening of the pinch roll to the first opening H1;

[0010] Step 3: When the head of the strip exits the finishing rolling F7 stand, the industrial camera starts and takes an image of the head of the strip. The industrial camera sends the image of the head of the strip to the pinch roller control assembly and then shuts down.

[0011] Step 4: The pinch roller control component determines whether the recognition result is abnormal crushing according to the image of the strip head. If so, step 5 is executed. If not, the pinch roller control component maintains the roller gap opening of the pinch roller at the first opening H1 and goes to step 6.

[0012] Step 5: The pinch roller control component calculates the second opening H2 of the pinch roller, and adjusts the roller gap opening of the pinch roller to the second opening H2;

[0013] Step 6: After the head of the strip passes through the pinch roller, the pinch roller control assembly adjusts the roller gap opening of the pinch roller to the third opening H3;

[0014] Step 7: After the tail of the strip leaves the finishing rolling F7 stand, the industrial camera starts and takes an image of the tail of the strip. The industrial camera sends the image of the tail of the strip to the pinch roll control assembly and then shuts down.

[0015] Step 8: The pinch roller control component determines whether the recognition result is abnormal crushing according to the image of the tail of the strip. If so, step 9 is executed. If not, the pinch roller control component maintains the roller gap opening of the pinch roller at the third opening H3 and goes to step 10.

[0016] Step 9: The pinch roller control component calculates the fourth opening H4 of the pinch roller, and the pinch roller control component adjusts the roller gap opening of the pinch roller to the fourth opening H4;

[0017] Step 10: After the tail of the strip passes through the pinch roller, the pinch roller control assembly adjusts the roller gap opening of the pinch roller to the fifth opening H5.

[0018] In the step 1, the vertical distance H between the industrial camera and the roller is in the range of 2-5m, the distance L between the industrial camera and the end of the exit guide plate of the finishing rolling F7 frame is 2-10m, and the horizontal distance Ls between the industrial camera and the end of the exit guide plate of the finishing rolling F7 frame is 4-8m; the roller located in the shooting area of ​​the industrial camera is an internally cooled water roller.

[0019] In the step 1, the pinch roller control assembly includes an industrial computer and an industrial PLC, the output end of the industrial camera is connected to the input end of the industrial computer, the output end of the industrial computer is connected to the input end of the industrial PLC, and the output end of the industrial PLC is electrically connected to the pinch roller.

[0020] The industrial camera transmits each frame of the captured image to the industrial computer in real time. The industrial computer identifies and classifies the head and tail morphologies of the strip through a deep learning classification algorithm, that is, it determines whether the head and tail surfaces of the strip are normally or abnormally punctured. If the surface of the strip is normal, the recognition result is output as 0 to the industrial PLC; if the surface of the strip is abnormally punctured, the recognition result is output as 1 to the industrial PLC. The industrial PLC adjusts and controls the roller gap opening of the pinch roller according to the position of the strip and the recognition result of the industrial computer.

[0021] In step 2, the calculation formula of the first opening H1 is:

[0022] H1=hh*k1 (1)

[0023] Where h is the target thickness of the strip issued by the process machine;

[0024] k1 is the initial setting thickness coefficient of the roller gap of the pinch roller, and the value range of k1 is 0.05-0.4.

[0025] In step 5, the calculation formula of the second opening H2 is:

[0026] H2=H1+h*k2 (2)

[0027] Among them, k2 is the thickness coefficient set for the roll gap head of the pinch roll, and the value range of k2 is 1.0-4.0.

[0028] In the step 5, after calculating the second opening H2 of the pinch roller, the pinch roller control component adjusts the roller gap opening of the pinch roller to the second opening H2 when the head of the strip reaches the first distance L1 in front of the pinch roller;

[0029] The value range of the first distance L1 is 3-10 meters.

[0030] In step 9, the calculation formula of the fourth opening H4 is:

[0031] H4=H3+h*k4 (3)

[0032] Among them, k4 is the thickness coefficient set for the tail of the roller gap of the pinch roller, and the value range of k4 is 10.0-30.0.

[0033] In the step 9, after calculating the fourth opening H4 of the pinch roller, the pinch roller control component adjusts the roller gap opening of the pinch roller to the fourth opening H4 when the tail of the strip reaches the second distance L2 in front of the pinch roller;

[0034] The value range of the second distance L2 is 4-8 meters.

[0035] The fifth opening H5 is the maximum roller gap opening of the pinch roller, and the value range of the fifth opening H5 is 180-200 mm.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention can quickly determine whether there is abnormal puncture at the head and tail of the strip based on recognition and deep learning of camera-shot images, and timely adjust the roller gap opening of the pinch roller when it is determined to be abnormal puncture. The online automatic adjustment of the pinch roller avoids damage to the roller surface of the pinch roller, and also improves the surface quality of the strip. There is no need to observe abnormal puncture of the strip with the naked eye and manually intervene to control the roller gap of the pinch roller, thus avoiding problems such as high observation error rate, poor timeliness of intervention action and low accuracy of manual adjustment, and greatly reducing the workload of operators.

[0038] 2. The present invention intervenes in the control at the head and tail of the strip, and in different stages of the strip coiling process, combined with functions such as the pinch roller gap and pressure pre-setting, automatically adjusts the pinch roller gap opening size, realizes real-time adjustment of the pinch roller gap based on distance or pressure, ensures the integrity of the pinch roller surface, minimizes the wear of the pinch roller, and also ensures the surface quality of the steel coil during the entire coiling process.

[0039] The present invention judges whether there are puncture abnormalities at the head and tail of the strip based on the images taken by the industrial camera, and accurately adjusts the roller gap opening of the pinch roller according to the puncture abnormality area to avoid contact between the pinch roller and the surface of the strip, thereby avoiding damage to the roller surface of the pinch roller and improving the surface quality of the strip, solving the problem of untimely and low accuracy of manual intervention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a front view of a strip hot rolling coiling device in the prior art, in which the arrow direction is the strip conveying direction;

[0041] Figure 2 It is a flow chart of the automatic control method of the coiling pinch roll surface protection based on rolling fracture identification of the present invention;

[0042] Figure 3 It is a front view of the strip hot rolling coiling equipment adopted by the automatic control method for protecting the roll surface of the coiling pinch roll based on rolling fracture identification of the present invention. In the figure, the arrow direction is the strip conveying direction.

[0043] In the figure, 1 finishing rolling F1 frame, 2 finishing rolling F2 frame, 3 finishing rolling F3 frame, 4 finishing rolling F4 frame, 5 finishing rolling F5 frame, 6 finishing rolling F6 frame, 7 finishing rolling F7 frame, 9 industrial camera, 11 side guide plate, 12 pinch roller, 13 industrial computer, 14 industrial PLC, 16 first coiler, 20 strip steel. DETAILED DESCRIPTION

[0044] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0045] Please see attached Figure 2 , an automatic control method for protecting the roll surface of a coiling pinch roll based on roll break identification, comprising the following steps:

[0046] Please see attached Figure 3 , Step 1: An industrial camera 9 is arranged obliquely above the exit of the finishing rolling F7 frame 7, so that the shooting area of ​​the industrial camera 9 can cover the exit opening range of the finishing rolling F7 frame 7, the industrial camera 9 is connected to the pinch roller control assembly, and the pinch roller control assembly is electrically connected to the pinch roller 12.

[0047] In the automatic control method of the present invention, the roller gap opening control mode of the pinch roller control component for the pinch roller 12 includes a position control mode and a pressure detection automatic control mode. The position control mode is to adjust the roller gap opening of the pinch roller 12 according to the position change of a certain position (such as the head end, the piercing position, and the tail end) on the strip 20, and the pressure detection automatic control mode is to adjust the roller gap opening of the pinch roller 12 according to the pressure fluctuation when the pinch roller 12 pinches the strip 20. The specific control models of the position control mode and the pressure detection automatic control mode can adopt the existing technology and will not be repeated here.

[0048] Preferably, the roller conveyor located in the shooting area of ​​the industrial camera 9 adopts an internally cooled water roller conveyor, which can avoid the influence of water mist caused by external cooling water on the shooting clarity to the greatest extent.

[0049] The vertical distance H between the industrial camera 9 and the roller is in the range of 2-5m, and the distance between the industrial camera 9 and the end of the outlet guide plate of the finishing rolling F7 frame 7, i.e., the shooting distance L of the industrial camera 9, is 2-10m. After the shooting length and the installation angle of the industrial camera 9 are determined, the horizontal distance Ls between the industrial camera 9 and the end of the outlet guide plate of the finishing rolling F7 frame 7 can be calculated according to the Pythagorean theorem as Ls= , the value range of Ls is usually 4-8m. Determine the installation position of the industrial camera 9 according to Ls and H. Preferably, the industrial camera 9 can adopt a CCD (charge coupled device) camera, and a suitable CCD camera can be selected according to requirements such as lens clarity and observation length.

[0050] The pinch roller control assembly includes an industrial computer 13 and an industrial PLC 14 (Programmable Logic Controller). The output end of the industrial camera 9 is connected to the input end of the industrial computer 13 through a twisted pair and an optical fiber. The output end of the industrial computer 13 is connected to the input end of the industrial PLC 14. The output end of the industrial PLC 14 is electrically connected to the pinch roller 12. The industrial camera 9 transmits each frame of the captured image to the industrial computer 13 in real time. The industrial computer 13 can use a deep learning classification algorithm to identify and classify the head and tail morphology of the strip 20, that is, to judge whether the head and tail surfaces of the strip 20 are normal or abnormally punctured. If the surface of the strip 20 is normal, the recognition result is output as 0 to the industrial PLC 14. If the surface of the strip 20 is abnormally punctured, the recognition result is output as 1 to the industrial PLC 14. The recognition delay time T1 of the industrial computer 13 is ≤100ms.

[0051] The method for the industrial computer 13 to identify and classify the head morphology of the strip 20 is: first, select two types of images of abnormal and normal rolling at the head position of the strip 20, and mark them with labels to classify the abnormal rolling into one group and the normal into one group. Then let the target detection algorithm learn the features of the head of the strip 20 to complete the model training, and establish a deep learning classification algorithm model. The convolutional neural network, recurrent neural network or deep neural network model can be used for model training and to establish the algorithm model, which will not be repeated here. Finally, the model is applied to the on-site real-time monitoring of whether the head of the strip 20 is abnormal or normal, and the identification results are output as 0 (normal) or 1 (abnormal rolling) and sent to the industrial PLC 14 for controlling the pinch roller 12. The method for the industrial computer 13 to identify and classify the tail morphology of the strip 20 is the same as that of the head, which will not be repeated here.

[0052] The industrial PLC 14 adjusts and controls the roller gap opening of the pinch roller 12 according to the position of the strip 20, the recognition result of the industrial computer 13 and other information. Taking the pinch roller 12 of the first coiler 16 as an example, the adjustment control process of the roller gap opening of the pinch roller 12 is as follows:

[0053] Step 2: When the head of the strip 20 exits the finishing rolling F3 stand 3, the industrial PLC 14 of the pinch roll control assembly uses a position control mode to set the roll gap opening of the pinch roll 12 to a first opening H1. The calculation formula of the first opening H1 is:

[0054] H1=hh*k1 (1)

[0055] Wherein, h is the target thickness of the strip steel 20 issued by the process machine.

[0056] k1 is the initial setting thickness coefficient of the roller gap of the pinch roller 12, and the value range of k1 is 0.05-0.4.

[0057] Step 3: When the head of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the head of the steel strip 20. The industrial camera 9 sends the image of the head of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0058] Step 4: The pinch roller control component determines whether the recognition result is abnormal crushing based on the image of the head of the strip 20. If so, execute step 5. If not, the industrial PLC 14 of the pinch roller control component maintains the roll gap opening of the pinch roller 12 at the first opening H1 and goes to step 6.

[0059] Step 5: The pinch roller control component calculates the second opening H2 of the pinch roller 12, and adjusts the roller gap opening of the pinch roller 12 to the second opening H2; the calculation formula of the second opening H2 is:

[0060] H2=H1+h*k2 (2)

[0061] Among them, k2 is the thickness coefficient set for the roll gap head of the pinch roll 12, and the value range of k2 is 1.0-4.0.

[0062] In the step 5, after calculating the second opening H2 of the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly does not immediately adjust the roll gap opening of the pinch roller 12 to the second opening H2. When the head of the strip 20 reaches the first distance L1 in front of the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly uses a position control mode to adjust the roll gap opening of the pinch roller 12 to the second opening H2.

[0063] Preferably, the value range of the first distance L1 is 3-10 meters.

[0064] Step 6: After the head of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly switches from the position control mode to the pressure detection automatic control mode, and adjusts the roller gap opening of the pinch roller 12 to the third opening H3. The third opening H3 of the pinch roller 12 can be automatically and dynamically adjusted according to the pressure fluctuation of the steel strip 20 on the pinch roller 12 using the existing pressure control method. The value of the third opening H3 can be calculated by the pinch roller control assembly according to the current production requirements of the steel strip 20, which will not be described in detail here.

[0065] Step 7: After the tail of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the tail of the steel strip 20. The industrial camera 9 sends the image of the tail of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0066] Step 8: The pinch roller control component determines whether the recognition result is abnormal crushing based on the image of the tail of the strip 20. If so, execute step 9. If not, the industrial PLC 14 of the pinch roller control component maintains the roller gap opening of the pinch roller 12 at the third opening H3 and goes to step 10.

[0067] Step 9: The pinch roller control component calculates the fourth opening H4 of the pinch roller 12, and the industrial PLC 14 of the pinch roller control component adjusts the roller gap opening of the pinch roller 12 to the fourth opening H4; the calculation formula of the fourth opening H4 is:

[0068] H4=H3+h*k4 (3)

[0069] Among them, k4 is a thickness coefficient set for the tail of the roller gap of the pinch roller 12, and the value range of k4 is 10.0-30.0.

[0070] In the step 9, after calculating the fourth opening H4 of the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly does not immediately adjust the roll gap opening of the pinch roller 12 to the fourth opening H4. When the tail of the strip 20 reaches the second distance L2 in front of the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly switches from the pressure detection automatic control mode to the position control mode, and adjusts the roll gap opening of the pinch roller 12 to the fourth opening H4.

[0071] Preferably, the second distance L2 has a value range of 4-8 meters.

[0072] Step 10: After the tail of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 of the pinch roller control assembly adjusts the roller gap opening of the pinch roller 12 to the fifth opening H5.

[0073] Preferably, the fifth opening H5 is the maximum roller gap opening of the pinch roller 12 , and the value range of the fifth opening H5 is 180-200 mm. The fifth opening H5 can be determined by the pinch roller control component according to the current production requirements of the strip steel 20 .

[0074] Embodiment 1:

[0075] Step 1: An industrial camera 9 is arranged above the outlet of the finishing rolling F7 frame 7 so that the shooting area of ​​the industrial camera 9 covers the opening range of the outlet of the finishing rolling F7 frame 7. The industrial camera 9 is connected to the pinch roller control assembly, and the pinch roller control assembly is electrically connected to the pinch roller 12.

[0076] The industrial camera 9 adopts a CCD camera, and the setting position of the industrial camera 9 is: H=4.18m, L=9.03m, Ls=8m.

[0077] The pinch roller control assembly includes an industrial computer 13 and an industrial PLC 14. The output end of the industrial camera 9 is connected to the input end of the industrial computer 13 through a twisted pair and an optical fiber. The output end of the industrial computer 13 is connected to the input end of the industrial PLC 14. The output end of the industrial PLC 14 is electrically connected to the pinch roller 12. The industrial camera 9 transmits each frame of the captured image to the industrial computer 13 in real time. The industrial computer 13 can use a deep learning classification algorithm to identify and classify the head and tail morphology of the strip 20. If the surface of the strip 20 is normal, the recognition result is output as 0 to the industrial PLC 14. If it is abnormally crushed, the recognition result is output as 1 to the industrial PLC 14. The recognition delay time T1 of the industrial computer 13 is ≤80ms. The industrial PLC 14 adjusts and controls the roller gap opening of the pinch roller 12 according to the position of the strip 20, the recognition result of the industrial computer 13 and other information. Taking the pinch roller 12 of the first coiler 16 as an example, the adjustment control process of the roller gap opening of the pinch roller 12 is as follows:

[0078] Please see attached Figure 3 , Step 2: When the head of the strip 20 leaves the finishing rolling F3 stand 3, the industrial PLC 14 uses the position control mode to set the roll gap opening of the pinch roll 12 to the first opening H1. In this embodiment, the target thickness of the strip 20 is h=2.5mm, the initial setting thickness coefficient of the roll gap of the pinch roll 12 is k1=0.1, and the first opening H1=hh*k1=2.25mm.

[0079] Step 3: When the head of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the head of the steel strip 20. The industrial camera 9 sends the image of the head of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0080] Step 4: The pinch roller control component determines that the recognition result is normal (the output result of the industrial computer 13 is 0) based on the image of the head of the strip steel 20, and keeps the roller gap opening of the pinch roller 12 at the first opening H1=2.25mm. Do not execute step 5, and go to step 6.

[0081] Step 6: After the head of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 switches from the position control mode to the pressure detection automatic control mode, and adjusts the roller gap opening of the pinch roller 12 to the third opening H3 = 2.25-2.65 mm. The third opening H3 of the pinch roller 12 can be automatically and dynamically adjusted according to the pressure fluctuation of the steel strip 20 on the pinch roller 12 using the existing pressure control method, which will not be described in detail here.

[0082] Step 7: After the tail of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the tail of the steel strip 20. The industrial camera 9 sends the image of the tail of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0083] Step 8: The pinch roller control component determines that the recognition result of the image of the tail of the strip 20 is abnormal crushing (the output result of the industrial computer 13 is 1).

[0084] Step 9: The pinch roller control component calculates the fourth opening H4 of the pinch roller 12. The pinch roller control component adopts the position control mode. When the tail of the strip 20 reaches the second distance L2=6.5m before the pinch roller 12, the industrial PLC 14 switches from the pressure detection automatic control mode to the position control mode, and adjusts the roller gap opening of the pinch roller 12 to the fourth opening H4.

[0085] In this embodiment, the thickness coefficient k4 of the roller gap tail of the pinch roller 12 is set to 12, and the fourth opening H4=H3+h*k4=32.25-32.65mm.

[0086] Step 10: After the tail of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 adjusts the roller gap opening of the pinch roller 12 to the fifth opening H5=185 mm.

[0087] Embodiment 2:

[0088] Step 1: An industrial camera 9 is arranged above the outlet of the finishing rolling F7 frame 7 so that the shooting area of ​​the industrial camera 9 covers the outlet opening range of the finishing rolling F7 frame 7. The industrial camera 9 is connected to the pinch roller control assembly, and the pinch roller control assembly is electrically connected to the pinch roller 12.

[0089] The industrial camera 9 adopts a CCD camera, and the setting position of the industrial camera 9 is: H=4.18m, L=9.03m, Ls=8m.

[0090] The pinch roller control assembly includes an industrial computer 13 and an industrial PLC 14. The output end of the industrial camera 9 is connected to the input end of the industrial computer 13 through a twisted pair and an optical fiber. The output end of the industrial computer 13 is connected to the input end of the industrial PLC 14. The output end of the industrial PLC 14 is electrically connected to the pinch roller 12. The industrial camera 9 transmits each frame of the captured image to the industrial computer 13 in real time. The industrial computer 13 can use a deep learning classification algorithm to identify and classify the head and tail morphology of the strip 20. If the surface of the strip 20 is normal, the recognition result is output as 0 to the industrial PLC 14. If it is abnormally crushed, the recognition result is output as 1 to the industrial PLC 14. The recognition delay time T1 of the industrial computer 13 is ≤80ms. The industrial PLC 14 adjusts and controls the roller gap opening of the pinch roller 12 according to the position of the strip 20, the recognition result of the industrial computer 13 and other information. Taking the pinch roller 12 of the first coiler 16 as an example, the adjustment control process of the roller gap opening of the pinch roller 12 is as follows:

[0091] Please see attached Figure 3 , Step 2: When the head of the strip 20 leaves the finishing rolling F3 stand 3, the industrial PLC 14 uses the position control mode to set the roll gap opening of the pinch roll 12 to the first opening H1. In this embodiment, the target thickness of the strip 20 is h=2.5mm, the initial setting thickness coefficient of the roll gap of the pinch roll 12 is k1=0.1, and the first opening H1=hh*k1=2.25mm.

[0092] Step 3: When the head of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the head of the steel strip 20. The industrial camera 9 sends the image of the head of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0093] Step 4: The pinch roller control component determines that the image of the head of the strip 20 shows abnormal puncture (the output result of the industrial computer 13 is 1), and maintains the roller gap opening of the pinch roller 12 at the first opening H1=2.25 mm.

[0094] Step 5: The pinch roller control component calculates the second opening H2 of the pinch roller 12. In this embodiment, the thickness coefficient k2 of the roller gap head of the pinch roller 12 is set to 2.0, and the second opening H2 = H1 + h*k2 = 7.25 mm.

[0095] When the head of the steel strip 20 reaches the first distance L1 = 9 m before the pinch roller 12 , the industrial PLC 14 uses the position control mode to adjust the roller gap opening of the pinch roller 12 to the second opening H2 .

[0096] Step 6: After the head of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 switches from the position control mode to the pressure detection automatic control mode, and adjusts the roller gap opening of the pinch roller 12 to the third opening H3 = 2.25-2.65 mm. The third opening H3 of the pinch roller 12 can be automatically and dynamically adjusted according to the pressure fluctuation of the steel strip 20 on the pinch roller 12 using the existing pressure control method, which will not be described in detail here.

[0097] Step 7: After the tail of the steel strip 20 exits the finishing rolling F7 frame 7, the industrial camera 9 starts and takes an image of the tail of the steel strip 20. The industrial camera 9 sends the image of the tail of the steel strip 20 to the pinch roller control assembly, and the industrial camera 9 is turned off.

[0098] Step 8: The pinch roller control component determines that the recognition result of the image of the tail of the strip 20 is abnormal crushing (the output result of the industrial computer 13 is 1).

[0099] Step 9: The pinch roller control component calculates the fourth opening H4 of the pinch roller 12. When the tail of the strip 20 reaches the second distance L2=6.5m before the pinch roller 12, the industrial PLC 14 switches from the pressure detection automatic control mode to the position control mode, and adjusts the roller gap opening of the pinch roller 12 to the fourth opening H4.

[0100] In this embodiment, the thickness coefficient k4 of the roller gap tail of the pinch roller 12 is set to 12, and the fourth opening H4=H3+h*k4=32.25-32.65mm.

[0101] Step 10: After the tail of the steel strip 20 passes through the pinch roller 12, the industrial PLC 14 adjusts the roller gap opening of the pinch roller 12 to the fifth opening H5=185 mm.

[0102] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatic control method for protecting the roll surface of the coiling pinch roll based on roll break identification, Its characteristics are: The following steps are involved: Step 1: an industrial camera (9) is arranged above the outlet of the finishing rolling F7 frame (7), so that the shooting area of ​​the industrial camera (9) can cover the opening range of the outlet of the finishing rolling F7 frame (7), and the industrial camera (9) is connected to the pinch roller (12) through the pinch roller control assembly; Step 2: When the head of the steel strip (20) exits the finishing rolling F3 stand (3), the pinch roll control assembly sets the roll gap opening of the pinch roll (12) to a first opening H1; Step 3: When the head of the steel strip (20) exits the finishing rolling F7 stand (7), the industrial camera (9) is started and takes an image of the head of the steel strip (20). The industrial camera (9) sends the image of the head of the steel strip (20) to the pinch roller control component and then turns off. Step 4: the pinch roller control component determines whether the recognition result is abnormal crushing based on the image of the head of the strip (20); if so, step 5 is executed; if not, the pinch roller control component maintains the roller gap opening of the pinch roller (12) at the first opening H1 and goes to step 6; Step 5: The pinch roller control component calculates the second opening H2 of the pinch roller (12), and adjusts the roller gap opening of the pinch roller (12) to the second opening H2; Step 6: After the head of the steel strip (20) passes through the pinch roller (12), the pinch roller control assembly adjusts the roller gap opening of the pinch roller (12) to a third opening H3; Step 7: After the tail of the steel strip (20) exits the finishing rolling F7 stand (7), the industrial camera (9) is started and takes an image of the tail of the steel strip (20). The industrial camera (9) sends the image of the tail of the steel strip (20) to the pinch roller control assembly and then turns off. Step 8: the pinch roller control component determines whether the recognition result is abnormal crushing based on the image of the tail of the strip (20); if so, step 9 is executed; if not, the pinch roller control component maintains the roller gap opening of the pinch roller (12) at the third opening H3 and goes to step 10; Step 9: the pinch roller control component calculates the fourth opening H4 of the pinch roller (12), and the pinch roller control component adjusts the roller gap opening of the pinch roller (12) to the fourth opening H4; Step 10: After the tail of the steel strip (20) passes through the pinch roller (12), the pinch roller control assembly adjusts the roller gap opening of the pinch roller (12) to a fifth opening H5.

2. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: In the step 1, the vertical distance H between the industrial camera (9) and the roller is in the range of 2-5 m, the distance L between the industrial camera (9) and the end of the outlet guide plate of the finishing rolling F7 frame (7) is in the range of 2-10 m, and the horizontal distance Ls between the industrial camera (9) and the end of the outlet guide plate of the finishing rolling F7 frame (7) is in the range of 4-8 m; the roller located in the shooting area of ​​the industrial camera (9) is an internally cooled water roller.

3. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: In the step 1, the pinch roller control assembly includes an industrial computer (13) and an industrial PLC (14), the output end of the industrial camera (9) is connected to the input end of the industrial computer (13), the output end of the industrial computer (13) is connected to the input end of the industrial PLC (14), and the output end of the industrial PLC (14) is electrically connected to the pinch roller (12).

4. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 3, Its characteristics are: The industrial camera (9) transmits each frame of the captured image to the industrial computer (13) in real time. The industrial computer (13) identifies and classifies the morphology of the head and tail of the steel strip (20) based on a deep learning classification algorithm, that is, it determines whether the surface of the head and tail of the steel strip (20) is normally or abnormally punctured. If the surface of the steel strip (20) is normal, the recognition result is output as 0 to the industrial PLC (14). If the surface of the steel strip (20) is abnormally punctured, the recognition result is output as 1 to the industrial PLC (14). The industrial PLC (14) adjusts and controls the roller gap opening of the pinch roller (12) according to the position of the steel strip (20) and the recognition result of the industrial computer (13).

5. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: In step 2, the calculation formula of the first opening H1 is: H1=hh*k1 (1) Wherein, h is the target thickness of the strip steel (20) issued by the process machine; k1 is the initial setting thickness coefficient of the roller gap of the pinch roller (12), and the value range of k1 is 0.05-0.

4.

6. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: In step 5, the calculation formula of the second opening H2 is: H2=H1+h*k2 (2) Wherein, k2 is a thickness coefficient set for the roll gap head of the pinch roll (12), and the value range of k2 is 1.0-4.

0.

7. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1 or 6, Its characteristics are: In the step 5, after calculating the second opening H2 of the pinch roller (12), the pinch roller control component adjusts the roller gap opening of the pinch roller (12) to the second opening H2 when the head of the steel strip (20) reaches the first distance L1 in front of the pinch roller (12); The value range of the first distance L1 is 3-10 meters.

8. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: In step 9, the calculation formula of the fourth opening H4 is: H4=H3+h*k4 (3) Wherein, k4 is a set thickness coefficient of the roller gap tail of the pinch roller (12), and the value range of k4 is 10.0-30.

0.

9. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1 or 8, Its characteristics are: In the step 9, after calculating the fourth opening H4 of the pinch roller (12), the pinch roller control component adjusts the roller gap opening of the pinch roller (12) to the fourth opening H4 when the tail of the steel strip (20) reaches the second distance L2 in front of the pinch roller (12); The value range of the second distance L2 is 4-8 meters.

10. The automatic control method for protecting the roll surface of the coiling pinch roll based on crushing identification according to claim 1, Its characteristics are: The fifth opening H5 is the maximum roller gap opening of the pinch roller (12), and the value range of the fifth opening H5 is 180-200 mm.

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