A method to improve the position tracking accuracy of MULPIC online water-cooled steel plate

Abstract

The invention relates to the technical field of MULPIC on-line water-cooled steel plate position tracking accuracy control for thick plates, and discloses a method for improving the MULPIC on-line water-cooled steel plate position tracking accuracy, comprising the following steps: since a pre-straightening machine input roller is connected with a finishing mill output roller FX7, by judging the speed states of the two groups of rollers, according to different speed conditions, the position of the steel plate image is calculated using the speeds of different rollers; the invention well solves the problem of large deviation between the image of the water-cooled steel plate and the actual object caused by uncertain factors such as steel plate slippage, fast steel throwing speed, and image not corrected in time, and controls the deviation within ±200 mm, greatly improves the steel plate image position tracking accuracy, and improves the overall temperature uniformity of the MULPIC water-cooled plate.

Description

Technical Field

[0001] The invention relates to the technical field of thick plate MULPIC online water-cooled steel plate position tracking accuracy control, in particular to a method for improving the MULPIC online water-cooled steel plate position tracking accuracy. Background Art

[0002] The MULPIC (multi-purpose interrupt cooling) device is a device used to cool thick steel plates from a certain temperature to a certain temperature after rolling in the finishing mill, and obtain good comprehensive performance through grain refinement and microstructure phase change. Due to the cooling of the rolling line cooling water, air, rollers, rollers, etc., the temperature of the steel plate in the length direction is uneven, especially in the head and tail areas of the steel plate. This requires the MULPIC device to set different cooling water volumes according to different positions of the steel plate. In order for MULPIC to accurately control different water volumes at different positions, the steel plate needs to have precise tracking accuracy.

[0003] For MULPIC online water-cooled steel plates, there are three gratings to establish the image position of the steel plate, calculate tracking and correct the error between the image and the real object. The points of the three gratings correspond to the ApproachPosition, Cooling Position and Delivery Position of the MULPIC cooling tracking sequence. After the finishing mill completes rolling and casts the steel, the Approach Position establishes tracking and uses the roller speed integral to calculate the position of the image of the steel plate. After the real steel plate passes the Cooling Position, it is compared and corrected with the image position. After the real steel plate passes the DeliveryPosition, it is compared with the image position, the tracking error of the steel plate is calculated, and used for tracking coefficient correction, which acts on the image tracking of the next steel plate.

[0004] The MULPIC cooling tracking sequence is divided into Approach Position, Cooling Position, and Delivery Position. When the finishing mill throws steel, the Approach Position is used to establish tracking. The roller speed integral is used to track and calculate the steel plate image position. The roller speed accuracy determines the error of MULPIC's steel plate head and tail tracking accuracy.

[0005] When the finishing mill finishes rolling and throws steel, the rolling line LCO control system coordinates. When the steel plate is transported to the physical position of the rolling line, the control authority of the steel plate is handed over to the pre-straightening machine, and the steel plate transportation speed is controlled by the pre-straightening machine. Before the steel plate is transported, the pre-straightening speed should be operated in the forward direction in advance, and then the image of the MULPIC water-cooled steel plate is calculated according to the current speed of the pre-straightening machine.

[0006] When there is no steel plate passing through and straightening the pre-straightening machine, in order to prevent the steel plate from abnormally penetrating into the pre-straightening machine and hitting the main equipment, the roller speed is set to reverse creeping. When the water-cooled steel plate slips, the steel throwing speed is fast, or the image is not corrected in time, etc., although the steel plate has been transported to the front of the pre-straightening machine, the pre-straightening machine roller speed only starts to run from reverse speed to forward speed. At this time, Approach Position calculates the steel plate image position using the current speed calculation of the pre-straightening, that is, the speed integral calculation of the transition from reverse speed to forward speed is used. This causes a deviation between the current steel plate image and the actual object, making the overall cooling tracking timing of MULPIC unable to be accurately executed, which seriously affects the temperature uniformity of the water-cooled plate. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] In view of the deficiencies in the prior art, the present invention provides a method for improving the position tracking accuracy of a MULPIC online water-cooled steel plate, which solves the problems existing in the above-mentioned background technology.

[0009] (II) Technical solution

[0010] To achieve the above object, the present invention provides the following technical solutions: A method for improving the position tracking accuracy of MULPIC online water-cooled steel plate, comprising the following steps: since the input roller table of the pre-straightening machine is connected with the output roller table FX7 of the finishing mill, by judging the speed state of the two groups of roller tables, according to different speed conditions, the speed of different roller tables is used to calculate the position of the steel plate image;

[0011] When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is less than the steel plate straightening speed and is not synchronized with the FX7 group roller speed, the steel plate image position uses the FX7 group roller speed to perform ApproachPosition integral calculation; when the pre-straightening machine speed rises to the straightening speed and is synchronized with the FX7 group speed, the steel plate image position uses the pre-straightening machine roller speed to perform Approach Position integral calculation; later, when the pre-straightening machine exit grating SMS4 detects the steel plate head, the steel plate image is corrected and synchronized with the real object again;

[0012] When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is consistent with the steel plate straightening speed and synchronized with the FX7 group roller speed, the image position of the steel plate directly uses the pre-straightening machine roller speed to perform Approach Position integral calculation; then, when the pre-straightening machine exit grating SMS4 detects the head of the steel plate, the image of the steel plate is corrected and synchronized with the actual object again.

[0013] (III) Beneficial effects

[0014] The present invention provides a method for improving the position tracking accuracy of a MULPIC online water-cooled steel plate, which has the following beneficial effects:

[0015] The present invention solves the problem of large deviation between the image of the water-cooled steel plate and the actual object caused by uncertain factors such as steel plate slippage, fast steel throwing speed, and failure to correct the image in time. The deviation is controlled within ±200mm, which greatly improves the steel plate image position tracking accuracy and improves the overall temperature uniformity of the MULPIC water-cooled plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the deviation diagram between the steel plate image and the actual object tracking before this technology is adopted;

[0017] Figure 2 Velocity map calculated from the steel plate image after using this technology;

[0018] Figure 3 This is the deviation diagram between the steel plate image and the actual object after using this technology. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The present invention provides a technical solution: a method for improving the position tracking accuracy of a MULPIC online water-cooled steel plate, comprising the following steps: since the input roller table of a pre-straightening machine is connected with the output roller table FX7 of a finishing mill, by judging the speed states of the two groups of roller tables, according to different speed conditions, the speeds of different roller tables are used to calculate the position of the steel plate image;

[0021] When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is less than the steel plate straightening speed and is not synchronized with the FX7 group roller speed, the steel plate image position uses the FX7 group roller speed to perform ApproachPosition integral calculation; when the pre-straightening machine speed rises to the straightening speed and is synchronized with the FX7 group speed, the steel plate image position uses the pre-straightening machine roller speed to perform Approach Position integral calculation; later, when the pre-straightening machine exit grating SMS4 detects the steel plate head, the steel plate image is corrected and synchronized with the real object again;

[0022] When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is consistent with the steel plate straightening speed and synchronized with the FX7 group roller speed, the image position of the steel plate directly uses the pre-straightening machine roller speed to perform Approach Position integral calculation; then, when the pre-straightening machine exit grating SMS4 detects the head of the steel plate, the image of the steel plate is corrected and synchronized with the actual object again.

[0023] Example 1

[0024] When the steel plate is transported to the Approach Position, the control of the rolling line LCO is handed over to the pre-straightening control. At this time, the entrance roller speed of the pre-straightening machine begins to slowly accelerate from -0.5m / s. Figure 1 As shown in the figure, before this technology is used, the speed calculated by MULPIC image tracking is the speed of the pre-straightening machine, and the pre-straightening machine speed should be the normal straightening speed. However, the speed calculated by MULPIC image tracking is integrated from the pre-straightening speed of -0.5m / s, which leads to errors in MULPIC image tracking calculation.

[0025] Example 2

[0026] After adopting this technology, the steel plate image position tracking situation is as follows Figure 2 and Figure 3 shown.

[0027] After the position correction is performed by the grating in front of the MULPIC machine, the final tracking deviation of the steel plate after it leaves the MULPIC is 139mm. Figure 3 shown.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for improving the position tracking accuracy of MULPIC online water-cooled steel plate, characterized in that: The method comprises the following steps: since the input roller table of the pre-straightening machine is connected with the output roller table of the finishing mill, the speed state of the two groups of roller tables is judged, and according to different speed conditions, the speed of different roller tables is used to calculate the position of the steel plate image; When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is less than the steel plate straightening speed and is not synchronized with the FX7 group roller speed, the image position of the steel plate is calculated by the ApproachPosition integral of the speed of the finishing mill output roller; when the speed of the pre-straightening machine rises to the straightening speed and is synchronized with the speed of the finishing mill output roller, the image position of the steel plate is calculated by the pre-straightening machine roller speed for the Approach Position integral; later, when the pre-straightening machine exit grating detects the head of the steel plate, the steel plate image is corrected and synchronized with the real object again; When the steel plate triggers the Approach Position grating and the pre-straightening machine input roller speed is consistent with the steel plate straightening speed and synchronized with the finishing mill output roller speed, the image position of the steel plate directly uses the pre-straightening machine roller speed to perform Approach Position integral calculation; then, when the pre-straightening machine exit grating detects the head of the steel plate, the image of the steel plate is corrected and synchronized with the actual object again.

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