Method for controlling the stop position of the tail end of a hot-rolled steel strip, device for controlling the stop position of the tail end of a hot-rolled steel strip, and thin coil

Abstract

To provide a stop position control method of a tail edge of a hot-rolled steel strip which can improve accuracy of distance tracking that stops the tail edge of the hot-rolled steel strip constituting a thin plate coil at a target position.SOLUTION: A stop position control method executes: a first step which detects the position of a tail edge center recess of a coarse hot-rolled steel strip, the position of the first cut tail edge part and the position of the second cut tail edge part of the coarse hot-rolled steel strip after the crop cut with a two-dimensional shape meter; a second step which detects the position of a pinch roll outlet side first tail edge part of a finished hot-rolled steel strip output from the outlet side of the pinch roll with a first laser meter and detects the position of a pinch roll outlet side second tail edge part with a second laser meter; a third step which calculates a tail edge correction amount for correcting the position of the tail edge of the finish hot-rolled steel strip; and a fourth step which controls the stop position of the tail edge of the finish hot-rolled steel strip on the basis of the tail edge correction amount.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for controlling the stopping position of the tail end of a hot-rolled steel strip, an apparatus for controlling the stopping position of the tail end of a hot-rolled steel strip, and a thin coil. [Background technology]

[0002] Finished hot-rolled steel strips produced by continuous hot rolling of steel sheets are wound into coils. The wound finished hot-rolled steel strips become thin coils. When winding the finished hot-rolled steel strips into coils to produce thin coils, it is necessary to control the tail end of the finished hot-rolled steel strip so that it stops at a predetermined position when winding of the finished hot-rolled steel strip is completed.

[0003] FIG. 6 is a schematic diagram showing an outline of a conventional method for winding a finished hot-rolled steel strip into a coil to produce a thin coil. As shown in FIG. 6(a), the winding section of a continuous hot rolling mill winds the finished hot-rolled steel strip, which is a hot-rolled steel strip fed from a pinch roll, around a mandrel to produce a thin coil. At the end of winding the finished hot-rolled steel strip, position control is performed so that the tail end of the finished hot-rolled steel strip stops at a predetermined position. As shown in FIG. 6(b), the control of the tail end position of the finished hot-rolled steel strip is performed by a computer recognizing the point when the tail end of the finished hot-rolled steel strip passes an on-board laser sensor installed on the exit side of the pinch roll, and then controlling the rotation speed of the mandrel motor from that point. Then, as shown in FIG. 6(c), the mandrel and the thin coil are rotated together on the crane roll until the tail end of the finished hot-rolled steel strip is positioned at the predetermined position when the thin coil is removed from the mandrel.

[0004] However, if the stopping position of the tail end of the finish hot rolled steel strip is not controlled, the stopping position of the tail end of the finish hot rolled steel strip on the outer periphery of the thin coil will not be aligned for each thin coil. If the thin coil is to be unwound from the mandrel of the coiler and transported to the coil yard, the tail end of the finish hot rolled steel strip constituting the thin coil will come into contact with other equipment or other thin coils during transport. As a result, if the position of the tail end of the finish hot rolled steel strip is not controlled, damage to other equipment and other thin coils will occur. Therefore, in order to control the stopping position of the tail end of the finish hot rolled steel strip, manual intervention by the coiler operator is required from the time the thin coil finishes winding until it begins to be unwound from the mandrel of the coiler, which increases the workload.

[0005] From this perspective, a method has been disclosed for accurately detecting the tail end of a rolled material even if the tail end shape of the rolled material being wound onto a winding machine of a rolling facility is irregular (for example, Patent Document 1). The method for detecting the tail end of a rolled material described in Patent Document 1 arranges thermal lump detectors in the width direction of the rolled material being wound onto a winding machine of a rolling facility, at the center of the conveying path and on both sides thereof, and detects the tail end position of the rolled material based on the timing at which all the thermal lump detectors change from on to off while the rolled material is being conveyed.

[0006] Also, a coiling control method for a hot rolled steel strip has been proposed that can perform fixed position stopping control of the tail end with high precision (for example, Patent Document 2). The coiling control method for a hot rolled steel strip described in Patent Document 2 compares the tail end position in the width direction in the two-dimensional shape of the tail end of the rough rolled steel strip output by a crop shape meter of the hot strip mill with the crop cut position, and when the tail end position at the center in the width direction is closer to the front end of the rough rolled steel strip than the crop cut position, corrects the tail end position at the center in the width direction detected by an in-machine laser sensor on the pinch roll outlet side of the hot strip mill to a position rearward of that position. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 11-254034 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-94798 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the above-mentioned conventional technology still has the following problems to be solved: In other words, the method of detecting the tail end of the rolled material described in Patent Document 1 detects the tail end position of the rolled material using a thermal mass detector arranged on the conveying path of the rolled material before the position where the winder of the rolling equipment is installed, and controls the tail end position of the rolled material using the detected tail end position of the rolled material as a starting point.

[0009] For this reason, the method of detecting the tail end of a rolled material described in Patent Document 1 cannot detect the tail end of a rolled material taking into consideration errors caused by changes in the shape of the rolled material after finish rolling by a finishing mill, changes in the shape of the finish rolled material due to cooling the rolled material after finish rolling, the amount of steel plate deflection that occurs on the hot run table, etc. As a result, the method of detecting the tail end of a rolled material described in Patent Document 1 has a problem in that the accuracy of distance tracking for stopping the tail end of the rolled material at a target position deteriorates.

[0010] In addition, in the hot rolled steel strip winding control method described in Patent Document 2, when the tail end position at the widthwise center in the two-dimensional shape of the tail end of the rough rolled steel strip is closer to the front end of the rough rolled steel strip than the crop cut position, the tail end position is corrected to a position behind that position even at the widthwise center detected by the on-board laser sensor on the outlet side of the pinch roll of the hot strip mill.

[0011] That is, the coiling control method for a hot-rolled steel strip described in Patent Document 2 controls the tail end position of the hot-rolled steel strip using the tail end position of the hot-rolled steel strip measured by a sensor arranged at the center of the steel sheet as the starting point. Therefore, when the shape of the tail end of the hot-rolled steel strip is irregular and the hot-rolled steel strip is shifted in the width direction, the correct center of the steel sheet cannot be used as the starting point for controlling the tail end position of the hot-rolled steel strip. Therefore, this coiling control method for a hot-rolled steel strip has a problem in that the tail end position of the hot-rolled steel strip corrected using the tail end position of the hot-rolled steel strip measured by the sensor arranged at the center of the steel sheet as the starting point does not match the tail end position of the finished hot-rolled steel strip on the outer periphery of the thin coil after the finished hot-rolled steel strip is wound around a mandrel to form a thin coil.

[0012] The present invention has been made in consideration of the above circumstances, and aims to provide a method for controlling the stopping position of the tail end of a hot-rolled steel strip, a device for controlling the stopping position of the tail end of a hot-rolled steel strip, and a thin sheet coil that can reduce the risk of the tail end of the hot-rolled steel strip interfering with other equipment when the thin sheet coil is removed from the mandrel by improving the accuracy of distance tracking that stops the tail end of the hot-rolled steel strip that constitutes the thin sheet coil at a target position. [Means for solving the problem]

[0013] Therefore, the present inventors have conducted various experiments to solve the above-mentioned problems, and as a result have found that it is possible to control the position of the tail end of a hot-rolled steel strip by using the tail end of a rough hot-rolled steel strip as the starting point and calculating a tail end correction amount for correcting the position of the tail end of a finish hot-rolled steel strip, taking into consideration errors caused by changes in the shape of the tail end of the hot-rolled steel strip and the amount of steel sheet deflection occurring on the hot run table. The present invention has been made based on the above-mentioned findings, and its gist is as follows.

[0014] That is, the method for controlling the stopping position of the tail end of a hot rolled steel strip according to the present invention, which advantageously solves the above-mentioned problems, comprises: 1. A method for controlling a stop position of a tail end of a finished hot rolled steel strip when the finished hot rolled steel strip is wound around a winding section having a mandrel to form a thin coil, comprising: a first step of detecting a two-dimensional shape of the tail end of the rough hot rolled steel strip that has been rough rolled, and detecting the position of a central recess at the tail end of the rough hot rolled steel strip and the positions of a first cut tail end and a second cut tail end of the rough hot rolled steel strip that have been formed by cropping convex portions formed adjacent to the left and right of the central recess using a two-dimensional shape meter; a second step of detecting, by a first laser meter, the position of a first tail end portion on the pinch roll outlet side corresponding to the first cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side after finish rolling the rough hot rolled steel strip after the crop cutting to form a finished hot rolled steel strip and then fed to a pinch roll, and detecting, by a second laser meter, the position of a second tail end portion on the pinch roll outlet side corresponding to the second cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side; a third step of calculating a tail end correction amount for correcting the position of the tail end of the finish hot rolled steel strip based on a first detection position of a first tail end portion on the pinch roll outlet side by the first laser meter and a laser detection difference distance formed between the first detection position and a second detection position of a second tail end portion on the pinch roll outlet side by the second laser meter; and a fourth step of controlling the stopping position of the tail end of the finish hot rolled steel strip based on the tail end correction amount.

[0015] In addition, it is considered that a more preferable solution for the method of controlling the stopping position of the tail end of a hot rolled steel strip according to the present invention may be (a) detecting the position of the first tail end on the pinch roll outlet side corresponding to the first cut tail end of the finished hot rolled steel strip and the position of the second tail end on the pinch roll outlet side corresponding to the second cut tail end using an area sensor that can measure the width direction of the finished hot rolled steel strip.

[0016] The present invention provides a stop position control device for the tail end of a hot rolled steel strip that advantageously solves the above problems, comprising: A control device for controlling a stop position of a tail end of a finished hot rolled steel strip when the finished hot rolled steel strip is wound by a winding section having a mandrel to form a thin coil, comprising: a first detection unit that detects a two-dimensional shape of the tail end of the rough hot rolled steel strip that has been rough rolled, and detects the position of a central recess at the tail end of the rough hot rolled steel strip and the positions of a first cut tail end and a second cut tail end of the rough hot rolled steel strip that have been formed by cropping convex portions formed adjacent to the left and right of the central recess using a two-dimensional shape meter; a second detection unit that detects, by a first laser meter, the position of a first tail end portion on the pinch roll outlet side corresponding to the first cut tail end portion of the finish hot rolled steel strip that is output from the pinch roll outlet side after finish rolling the rough hot rolled steel strip after the crop cutting to form a finish hot rolled steel strip and then sent to the pinch roll; and that detects, by a second laser meter, the position of a second tail end portion on the pinch roll outlet side corresponding to the second cut tail end portion of the finish hot rolled steel strip that is output from the pinch roll outlet side. a third detection unit that calculates a tail end correction amount for correcting the position of the tail end of the finish hot rolled steel strip based on a first detection position of a first tail end portion on the pinch roll outlet side by the first laser meter and a laser detection difference distance formed between the first detection position and a second detection position of a second tail end portion on the pinch roll outlet side by the second laser meter; a position control unit that controls the stop position of the tail end of the finish hot rolled steel strip based on the tail end correction amount.

[0017] The thin coil according to the present invention, which advantageously solves the above-mentioned problems, is characterized in that it is produced by the above-mentioned device for controlling the stopping position of the tail end of a hot-rolled steel strip. [Effects of the Invention]

[0018] According to the present invention, even if the shape of the tail winding end of the hot-rolled steel strip is irregular and shifted in the width direction of the hot-rolled steel strip, the risk of the tail winding end of the hot-rolled steel strip interfering with other equipment when the thin coil is removed from the mandrel can be reduced. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic diagram showing a thin sheet coil production line for implementing a method for controlling the stopping position of the tail end of a hot-rolled steel strip according to the present invention. [Figure 2] 1 is a schematic diagram showing the coordinates of the tail end of a hot-rolled steel strip coiled by the method for controlling the stop position of the tail end of the hot-rolled steel strip according to the present invention, measured by a two-dimensional shape meter. [Figure 3] 1 is a schematic diagram showing the coordinates of the tail end of a hot-rolled steel strip measured by a laser meter at the tail end of the hot-rolled steel strip wound by the method for controlling the stop position of the tail end of the hot-rolled steel strip according to the present invention. [Figure 4] FIG. 1 is an explanatory diagram showing the relationship between the tail end coordinates measured by a laser meter at the winding tail end of a hot rolled steel strip that is wound by the method for controlling the stop position of the tail end of a hot rolled steel strip according to the present invention and the correction amount of the tail end position of the hot rolled steel strip calculated from the tail end coordinates. [Figure 5] 1 is a graph showing the results of a simulation of control of the tail end of the finish hot-rolled steel strip obtained in Example 1. [Figure 6] 1 is a schematic diagram showing a conventional method for controlling the fixed position stopping of the tail end of a finish rolled steel strip. DETAILED DESCRIPTION OF THE INVENTION

[0020] [First embodiment] A method for controlling the stopping position of the tail end of a hot-rolled steel strip according to the first embodiment will be described. The method for controlling the stopping position of the tail end of a hot rolled steel strip according to this embodiment includes a first step of detecting a two-dimensional shape of the tail end of a rough hot rolled steel strip, and detecting the position of a central concave portion of the tail end of the rough hot rolled steel strip and the position of a first cut tail end portion and a second cut tail end portion of the rough hot rolled steel strip after cropping, which are formed by cropping convex portions formed adjacent to the left and right of the central concave portion, using a two-dimensional shape meter; and a second step of detecting a position of a first cut tail end portion and a second cut tail end portion of the finish hot rolled steel strip after finish rolling the rough hot rolled steel strip after cropping, which is formed by feeding the finish hot rolled steel strip to pinch rolls and then outputting the finish hot rolled steel strip from the outlet side of the pinch rolls. The method includes a second step of detecting the position of a first tail end portion on the pinch roll outlet side by a first laser meter and detecting the position of a second tail end portion on the pinch roll outlet side corresponding to the second cut tail end by a second laser meter; a third step of calculating a tail end correction amount for correcting the position of the tail end of the finished hot rolled steel strip based on a first detection position of the first tail end portion on the pinch roll outlet side by the first laser meter and a laser detection difference distance formed between the first detection position and a second detection position of the second tail end portion on the pinch roll outlet side by the second laser meter; and a fourth step of controlling the stop position of the tail end of the finished hot rolled steel strip based on the tail end correction amount. Hereinafter, each step included in the method for controlling the stopping position of the tail end of a hot rolled steel strip according to this embodiment will be described with reference to the drawings.

[0021] <About the first process> The method for controlling the stopping position of the tail end of a hot-rolled steel strip according to this embodiment includes a step of detecting the two-dimensional shape of the rough-rolled rough hot-rolled steel strip and detecting the position of the central recess at the tail end of the rough hot-rolled steel strip and the positions of the first cut tail end and the second cut tail end of the rough hot-rolled steel strip after cropping, which are formed by cropping the convex portions formed adjacent to the left and right of the central recess at the tail end, using a two-dimensional shape meter. That is, the first step included in the method for controlling the stopping position of the tail end of a hot-rolled steel strip in this embodiment is a step of detecting, using a two-dimensional shape meter, the position of the central recess at the tail end of the rough hot-rolled steel strip and the position of the first cut tail end and the position of the second cut tail end that the rough hot-rolled steel strip has after cropping, which are formed by cropping the convex portions formed adjacent to the left and right of the central recess at the tail end.

[0022] Fig. 1 is a schematic diagram showing a thin plate coil production line for carrying out a method for controlling the stop position of the tail end of a hot rolled steel strip according to the present invention. As shown in Fig. 1, the thin plate coil production line 100 for carrying out the method for controlling the stop position of the tail end of a hot rolled steel strip includes a roughing mill 101, a two-dimensional shape measuring device 102, a crop shear 103, a finishing mill 104, pinch rolls (PR inside the winder) 105, a laser meter 106, a tail end stop controller 107, a hot run table 108, a mandrel 109, and a mandrel drive unit M.

[0023] A slab used as a rolling material for a rough hot rolled steel strip is transported to a rough rolling mill 101 and rough rolled by the rough rolling mill 101 to be processed into a rough hot rolled steel strip 200. The shape of the rough hot rolled steel strip 200 is detected by a two-dimensional shape measuring device 102. The two-dimensional shape measuring device 102 detects the two-dimensional shape of the rough hot rolled steel strip 200 and detects the position of a central recess 201 at the tail end of the rough hot rolled steel strip 200.

[0024] FIG. 2 is a schematic diagram showing the coordinates of the tail end of a hot-rolled steel strip being wound, measured by a two-dimensional shape measuring device, using a method for controlling the tail end stop position of a hot-rolled steel strip according to the present invention. Specifically, FIG. 2(a) is a schematic diagram showing the position of the central recessed portion at the tail end of a rough hot-rolled steel strip. As shown in FIG. 2(a), the position of the central recessed portion at the tail end 201 of the rough hot-rolled steel strip 200 can be identified using two-dimensional coordinates (x, y). The position of the central recessed portion at the tail end 201 of the rough hot-rolled steel strip 200 is defined as P0 (0, 0). The rough hot-rolled steel strip 200 is then transported to the crop shear 103.

[0025] 2(b) is a schematic diagram showing an outline of the rough hot rolled steel strip after the convex portions formed adjacent to the left and right of the tail end central depression of the rough hot rolled steel strip have been cropped. As shown in FIG. 2(b), the crop shear 103 crops out a left convex portion 202 and a right convex portion 203, which are convex portions formed adjacent to the tail end central depression 201 of the rough hot rolled steel strip 200 on the left and right sides. After the left convex portion 202 and the right convex portion 203 have been cropped out, the rough hot rolled steel strip 204 is formed with a first cut tail end portion 205 located adjacent to the tail end central depression 201 on the left and right sides, and a second cut tail end portion 206 located on the right side of the tail end central depression 201.

[0026] The cutting of the rough hot rolled steel strip 200 by the crop shear 103 is performed parallel to the width direction of the rough hot rolled steel strip 200. Therefore, the first cut tail end portion 205 located on the left side of the tail end central recess 201 and the second cut tail end portion 206 located on the right side of the tail end central recess 201 are positioned opposite each other.

[0027] The two-dimensional shape measuring device 102 detects the two-dimensional shape of the rough hot rolled steel strip 200 before being cropped, and detects a first cut tail end 205 and a second cut tail end 206 of the rough hot rolled steel strip 204 after being cropped. For this reason, the two-dimensional shape measuring device 102 is preferably installed on either side of the crop shear 103 to measure the two-dimensional shape of the rough hot rolled steel strip 200 before being cropped and the two-dimensional shape of the rough hot rolled steel strip 204 after being cropped. Alternatively, the two-dimensional shape measuring device 102 may be installed either on either side of the crop shear 103 to measure the two-dimensional shape of either the rough hot rolled steel strip 200 before being cropped or the two-dimensional shape of the rough hot rolled steel strip 204 after being cropped. Here, the positions of the first cut tail end portion 205 and the second cut tail end portion 206 of the rough hot rolled steel strip 204 after being cropped can be specified using two-dimensional coordinates (x, y). The position of the first cut tail end portion 205 of the rough hot rolled steel strip 204 after being cropped can be defined as Pcs1(x1, ycs1), and the position of the first cut tail end portion 206 can be defined as Pcs2(x2, ycs2).

[0028] Thus, the first step included in the method for controlling the stopping position of the tail end of a hot-rolled steel strip according to this embodiment is to identify the position of the central recess 201 at the tail end of the rough hot-rolled steel strip 200, and the positions of the first cut tail end 205 and the second cut tail end 206 of the rough hot-rolled steel strip 204 after being cropped, using two-dimensional coordinates.

[0029] <About the second process> The method for controlling the stopping position of the tail end of a hot-rolled steel strip according to this embodiment includes the steps of: detecting, with a first laser meter, the position of a first tail end on the pinch roll outlet side corresponding to the first cut tail end of the finished hot-rolled steel strip that is output from the outlet side of the pinch roll after the rough hot-rolled steel strip after the crop cut is finish-rolled to form the finished hot-rolled steel strip and then sent to the pinch roll; and detecting, with a second laser meter, the position of a second tail end on the pinch roll outlet side corresponding to the second cut tail end. That is, the second step included in the method for controlling the stopping position of the tail end of a hot-rolled steel strip according to this embodiment is a step of detecting, using a laser meter, the positions of the first tail end and the second tail end on the pinch roll outlet side of the finished hot-rolled steel strip that is output from the outlet side of the pinch roll after the rough hot-rolled steel strip after crop cutting has been finish-rolled and transported to the pinch roll.

[0030] The rough hot rolled steel strip 204 after being cropped is transported to the finishing rolling mill 104 and finish rolled. The rough hot rolled steel strip 204 after being cropped is finish rolled to form a finish hot rolled steel strip 300. The finish hot rolled steel strip 300 is then transported to the pinch rolls 105. The finish hot rolled steel strip 300 transported to the pinch rolls 105 is rolled in the longitudinal direction of the finish hot rolled steel strip 300 by finish rolling. The finish hot rolled steel strip 300 transported to the pinch rolls 105 is then output from the outlet side of the pinch rolls 105 in the winder.

[0031] 2(c) is a schematic diagram showing an outline of the finish hot rolled steel strip transported to the pinch rolls. As shown in FIG. 2(c), the finish hot rolled steel strip 300 output from the outlet side of the pinch rolls 105 retains the tail end central recess 201 of the rough hot rolled steel strip 200 as the tail end central recess 301. In other words, the position of the tail end central recess 301 of the finish hot rolled steel strip 300 output from the outlet side of the pinch rolls 105 coincides with the position of the tail end central recess 201 of the rough hot rolled steel strip 200.

[0032] The finished hot rolled steel strip 300 output from the outlet side of the pinch rolls 105 has a pinch roll outlet first tail end 302 corresponding to the first cut tail end 205 of the rough hot rolled steel strip 204 after being cropped, and a pinch roll outlet second tail end 303 corresponding to the second cut tail end 206 of the rough hot rolled steel strip 204. The pinch roll outlet first tail end 302 and the pinch roll outlet second tail end 303 are positioned opposite each other.

[0033] Here, the positions of the pinch roll outlet side first tail end portion 302 and the pinch roll outlet side second tail end portion 303 can be specified using two-dimensional coordinates (x, y).The position of the pinch roll outlet side first tail end portion 302 can be specified as P1(x1, y1), and the position of the pinch roll outlet side second tail end portion 303 can be specified as P2(x1, y2).

[0034] The relationship between the longitudinal coordinate y1 of the finished hot rolled steel strip 300 at position P1 of the first tail end 302 on the pinch roll outlet side and the longitudinal coordinate ycs1 of the rough hot rolled steel strip 204 at position Pcs of the first cut tail end 205 of the rough hot rolled steel strip 204 after being cropped can be calculated using the following relational expression (1), taking into account the reduction rate in the longitudinal finish rolling of the thin plate coil.

[0035]

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[0036] In relational expression (1), y1: longitudinal coordinate of the finished hot rolled steel strip 300 at the position P1 of the first tail end portion 302 on the pinch roll outlet side; ycs1: longitudinal coordinate of the first cut tail end 205 of the rough hot rolled steel strip 204 after being cropped; R in : The thickness of the finished hot-rolled steel strip 300 before entering the pinch roll 105 in the winding machine, R out : indicates the thickness of the finished hot-rolled steel strip 300 output from the pinch roll 105 in the winding machine. where (R out / R in ) is the reduction rate of the finished hot rolled steel strip 300.

[0037] Similarly, the relationship between the longitudinal coordinate y2 of the finished hot rolled steel strip 300 at position P2 of the second tail end 303 on the pinch roll outlet side and the longitudinal coordinate ycs2 of the rough hot rolled steel strip 204 at position Pcs of the second cut tail end 206 of the rough hot rolled steel strip 204 after being cropped can be calculated using the following relational expression (2), taking into account the reduction rate in the longitudinal finish rolling of the thin plate coil.

[0038]

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[0039] In relational expression (2), y2: longitudinal coordinate of the finished hot rolled steel strip 300 at the position P2 of the second tail end portion 303 on the pinch roll outlet side, ycs2: the longitudinal coordinate of the second cut tail end 206 of the rough hot rolled steel strip 204 after being cropped; R in : The thickness of the finished hot-rolled steel strip 300 before entering the pinch roll 105 in the winding machine, R out : indicates the thickness of the finished hot-rolled steel strip 300 output from the pinch roll 105 in the winding machine.

[0040] Thus, the second step included in the method for controlling the stopping position of the tail end of a hot-rolled steel strip in this embodiment is to detect the position of the first tail end 302 on the pinch roll outlet side of the pinch roll 105 of the finished hot-rolled steel strip 300 output from the outlet side of the pinch roll 105 using the first laser meter 161, and to detect the position of the second tail end 303 on the pinch roll outlet side of the pinch roll 105 using the second laser meter 162.

[0041] <About the third process> The method for controlling the stopping position of the tail end of a hot-rolled steel strip in this embodiment includes a step of calculating a tail end correction amount for correcting the position of the tail end of the finished hot-rolled steel strip based on the position of the first tail end on the outlet side of the pinch roll, the position of the second tail end on the outlet side of the pinch roll, the first laser detection position by the first laser meter, the second laser detection position by the second laser meter, and the laser detection difference distance formed between the first laser detection position and the second laser detection position. That is, the third step included in the method for controlling the tail end stop position of the hot rolled steel strip according to this embodiment calculates a tail end correction amount for correcting the position of the tail end of the finished hot rolled steel strip based on the first laser detection position by the first laser, the second laser detection position by the second laser, and the laser detection difference distance formed between the first laser detection position and the second laser detection position.

[0042] 3 is a schematic diagram showing coordinates of the tail end portion measured by a laser meter at the winding tail end of a hot rolled steel strip that is wound by the method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment. Specifically, when the laser meter 106 is composed of a first laser meter 161 and a second laser meter 162, FIG. 3 shows the relationship between the first laser detection position Q1 by the first laser meter 161, the second laser detection position Q2 by the second laser meter 162, the inter-laser distance α formed between the first laser meter 161 and the second laser meter 162, and the laser detection difference distance β formed between the first laser detection position Q1 and the second laser detection position Q2.

[0043] As shown in Fig. 3, the positions of a first tail end portion 302 on the pinch roll outlet side and a second tail end portion 303 on the pinch roll outlet side of the finished hot rolled steel strip 300 output from the outlet side of the pinch roll 105 are detected by a laser meter 106 installed between the outlet side of the pinch roll 105 and the mandrel 109. Two or more laser meters 106 must be installed. The laser meter 106 may be composed of, for example, a first laser meter 161 and a second laser meter 162 installed one behind the other in the conveying direction of the finished hot rolled steel strip 300.

[0044] The first laser meter 161 and the second laser meter 162 are installed at an inter-laser distance α, with the equipment center line 181 of the hot run table 108 as their center line. The distance between the first laser meter 161 and the equipment center line 181 of the hot run table 108 is half the inter-laser distance α (α / 2). The distance between the second laser meter 162 and the equipment center line 181 of the hot run table 108 is half the inter-laser distance α (α / 2).

[0045] The laser detection difference distance β formed between the first laser detection position Q1 and the second laser detection position Q2 is a speed V at which the finished hot rolled steel strip 300 is wound around the mandrel 109. coilFocusing on the relationship between ΔT, which is the time difference between the time when the tail end of the finished hot rolled steel strip 300 passes the first laser detection position Q1 and the time when the tail end of the finished hot rolled steel strip 300 passes the second laser detection position Q2, this is expressed by the following relational expression (3):

[0046]

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[0047] 4 is an explanatory diagram showing the relationship between the tail end coordinates measured by a laser meter at the winding tail end of a hot rolled steel strip wound by the method for controlling the tail end stop position of a hot rolled steel strip according to this embodiment and the correction amount for the tail end position of the hot rolled steel strip calculated from the tail end coordinates. Specifically, FIG. 4(a) is an explanatory diagram showing the relationship between the first laser detection position Q1, the second laser detection position Q2, the inter-laser distance α, and the laser detection difference distance β. FIG. 4(b) is an explanatory diagram for explaining the tail end correction amount Y for correcting the position of the tail end of the finished hot rolled steel strip, assuming the relationship between the first laser detection position Q1, the second laser detection position Q2, the inter-laser distance α, and the laser detection difference distance β.

[0048] 4(a)-(b), the first laser detection position Q1 is located on a straight line connecting the tail end central recess 301 and the first tail end 302 on the pinch roll outlet side. The second laser detection position Q2 is located on a straight line connecting the tail end central recess 301 and the second tail end 303 on the pinch roll outlet side.

[0049] Here, when the position of the first laser detection position Q1 is specified by two-dimensional coordinates (s, t), and the relationship between the inter-laser distance α and the laser detection difference distance β shown in Fig. 4(a) is taken into consideration, the position of the second laser detection position Q2 can be specified by two-dimensional coordinates (s+α, t+β).The relationships expressed by the following relational expressions (4) and (5) hold among the position P1(x1, y1) of the first tail end portion 302 on the pinch roll outlet side, the position P2(x1, y2) of the second tail end portion 303 on the pinch roll outlet side, the inter-laser distance α, and the laser detection difference distance β.

[0050]

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[0051]

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[0052] The longitudinal coordinate t of the tail end of the finished hot rolled steel strip 300 at the two-dimensional coordinates (s, t) where the position of the first laser detection position Q1 is identified by the above relational expressions (4) and (5) is calculated by the following relational expression (6).

[0053]

number

[0054] Based on the relationship between the longitudinal coordinate t of the tail end of the finished hot rolled steel strip 300 at the two-dimensional coordinate (s, t) that identifies the position of the first laser detection position Q1 calculated in this manner, the longitudinal coordinate y1 of the tail end of the finished hot rolled steel strip 300 at P1 (x1, y1) that identifies the position of the first tail end 302 on the pinch roll outlet side, and the longitudinal coordinate y2 of the tail end of the finished hot rolled steel strip 300 at P2 (x2, y2) that identifies the position of the second tail end 303 on the pinch roll outlet side, and the laser detection difference distance β, the tail end correction amount Y for correcting the position of the tail end of the finished hot rolled steel strip can be calculated as follows. Similarly, the two-dimensional coordinates (s+α, t+β) that identify the position of the second laser detection position Q2 can be identified based on the two-dimensional coordinates (s, t) that identify the position of the first laser detection position Q1. That is, in the third step, the tail edge correction amount Y is determined based on the magnitude relationship between the position of the tail edge central recess 201 and the sum of the tail edge central recess 201 and the laser detection difference distance β, in accordance with the positional relationship between the position of the first tail edge 302 on the pinch roll outlet side and the position of the second tail edge 303 on the pinch roll outlet side. Specifically, the tail edge correction amount Y is calculated as follows according to conditions A to D.

[0055]

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[0056]

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[0057]

number

[0058]

number

[0059] As described above, the third step included in the method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment calculates a tail end correction amount Y for correcting the position of the tail end of the finish hot rolled steel strip in accordance with conditions A to D, based on the relationship between the longitudinal coordinate t of the tail end of the finish hot rolled steel strip 300, the longitudinal coordinates y1, y2 of the tail end of the finish hot rolled steel strip 300, and the laser detection difference distance β. That is, the tail end correction amount Y is determined based on the magnitude relationship between the position of the tail end central recessed portion 301 and the sum of the tail end central recessed portion 301 and the laser detection difference distance β, in accordance with the positional relationship between the position of the pinch roll delivery side first tail end portion 302 and the pinch roll delivery side second tail end portion 303.

[0060] <About the fourth process> The method for controlling the stopping position of the tail end of a hot rolled steel strip according to this embodiment includes a step of controlling the stopping position of the tail end of the finish hot rolled steel strip based on the tail end correction amount. That is, the fourth step included in the method for controlling the stopping position of the tail end of a hot-rolled steel strip in this embodiment is to send the value of the tail end correction amount Y obtained in the third step as a pulse wave to the tail end stop controller 107, transmit it to the mandrel driving unit M, and control the stopping position of the tail end of the finished hot-rolled steel strip 300 by rotating and driving the mandrel 109.

[0061] The stop position of the tail end of the finish hot rolled steel strip 300 is controlled appropriately according to the value of the tail end correction amount Y. The stop position of the tail end of the finish hot rolled steel strip 300 is controlled by determining the rotation direction and rotation amount of the mandrel 109 according to the value of the tail end correction amount Y. The value of the tail end correction amount Y is output to the tail end stop controller 107. The muller is rotated from the position where the tail end has been removed to a tail end stop angle determined based on the outer peripheral distance of the thin coil, the remaining distance in the facility, and the value of the tail end correction amount Y. Then, by controlling the stopping position of the tail end of the finished hot rolled steel strip 300, it is possible to obtain thin coils with aligned tail end stopping positions.

[0062] As described above, the method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment includes the first to fourth steps, calculates the tail end correction amount, and can accurately control the stop position of the finish hot rolled steel strip based on the tail end correction amount. In other words, the method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment can solve the problem of errors caused by changes in the shape of the hot rolled steel strip and the amount of deflection of the hot run table by installing two or more laser meters in the winder and comparing the measurement results by these laser meters with the tail end shape measured by the two-dimensional shape measuring meter.

[0063] As described above, according to the invention relating to the first embodiment, even if the shape of the tail end of the hot-rolled steel strip is irregular and shifted in the width direction of the hot-rolled steel strip, the stopping position of the tail end of the hot-rolled steel strip can be controlled.

[0064] [Second embodiment] A method for controlling the stop position of the tail end of a hot rolled steel strip according to a second embodiment will be described. The method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment is characterized in that, in the method for controlling the stop position of the tail end of a hot rolled steel strip according to the above-mentioned embodiments, the position of a first tail end on the pinch roll outlet side corresponding to the first cut tail end and the position of a second tail end on the pinch roll outlet side corresponding to the second cut tail end of the finished hot rolled steel strip are detected by an area sensor capable of measuring the width direction of the finished hot rolled steel strip. Hereinafter, the characteristic steps included in the method for controlling the stopping position of the tail end of a hot rolled steel strip according to this embodiment will be described.

[0065] The method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment uses an area sensor to detect the positions of the first tail end portion 302 on the pinch roll outlet side and the second tail end portion 303 on the pinch roll outlet side. The area sensor acquires information necessary for controlling the stop position of the tail end of the hot rolled steel strip within a range set on the hot run table 108. That is, in the method for controlling the stop position of the tail end of a hot rolled steel strip according to this embodiment, the area between the first laser detection position and the second laser detection position is set as a detection area, and the positions of the first tail end portion 302 on the pinch roll outlet side and the second tail end portion 303 on the pinch roll outlet side that have passed through this detection area are detected.

[0066] The area sensor may be any sensor capable of detecting the position of the first tail end 302 on the pinch roll exit side and the position of the second tail end 303 on the pinch roll exit side, and may be, for example, an infrared area sensor, an ultrasonic area sensor, or a visible light area sensor.

[0067] As described above, according to the invention of the second embodiment, the position of the tail end portion on the outlet side of the pinch roll can be detected by an area sensor without installing multiple laser meters, and the tail end correction amount can be calculated to control the stopping position of the tail end of the hot rolled steel strip.

[0068] [Third embodiment] A description will be given of a control device for the tail end stop position of a hot rolled steel strip according to a third embodiment. The control device for the tail end stop position of a hot rolled steel strip according to this embodiment is a device for realizing the control method for the tail end stop position of a hot rolled steel strip according to the above-mentioned embodiment.

[0069] The tail end stop position control device for a hot rolled steel strip according to this embodiment includes a first detection unit that detects the two-dimensional shape of a rough hot rolled steel strip by using a two-dimensional shape measuring device to detect the position of a central recess at the tail end of the rough hot rolled steel strip and the position of a first cut tail end portion and a second cut tail end portion of the rough hot rolled steel strip after cropping, the first cut tail end portion and the second cut tail end portion being formed by cropping the convex portions formed adjacent to the left and right of the central recess at the tail end of the rough hot rolled steel strip; and a pinch roll exit position control device that detects the position of a pinch roll exit position of the finish hot rolled steel strip output from the exit side of the pinch roll after the finish hot rolled steel strip is fed to the pinch roll. a second detection unit that detects the position of a first tail end portion on the pinch roll exit side using a first laser meter and detects the position of a second tail end portion on the pinch roll exit side using a second laser meter; a calculation unit that calculates a tail end correction amount for correcting the position of the tail end of the finished hot rolled steel strip based on the position of the first tail end portion on the pinch roll exit side, the position of the second tail end portion on the pinch roll exit side, a first laser detection position by the first laser, a second laser detection position by the second laser, and a laser detection difference distance formed between the first laser detection position and the second laser detection position; and a control unit that controls the stop position of the tail end of the finished hot rolled steel strip based on the tail end correction amount. Hereinafter, each of the components constituting the stop position control device for the tail end of a hot rolled steel strip according to this embodiment will be described.

[0070] <About the first detection unit> The tail end stop position control device for a hot rolled steel strip according to this embodiment includes a first detection unit. The first detection unit is only required to detect the two-dimensional shape of the rough hot rolled steel strip 200 after rough rolling and the position of the tail end central recess 201 of the rough hot rolled steel strip 200. Furthermore, the first detection unit is only required to detect the positions of the first cut tail end 205 and the second cut tail end 206 of the rough hot rolled steel strip 204 after cropping, which are formed by cropping the left convex portion 202 and the right convex portion 203 formed adjacent to the left and right of the tail end central recess 201. For this reason, the first detection units are preferably installed before and after the crop shear 103 in order to measure the two-dimensional shape of the rough hot rolled steel strip 200 before cropping and the two-dimensional shape of the rough hot rolled steel strip 204 after cropping. Furthermore, the first detection unit may be installed either before or after the crop shear 103 to measure the two-dimensional shape of either the rough hot rolled steel strip 200 before cropping or the rough hot rolled steel strip 204 after cropping. The first detection unit corresponds to the two-dimensional shape measuring meter 102. For example, the first detection unit may be a reflective two-dimensional laser displacement meter, as long as it can perform measurements by moving either the sensor head of the reflective two-dimensional laser displacement meter or the workpiece.

[0071] <About the second detection unit> The stop position control device for the tail end of a hot rolled steel strip according to this embodiment includes a second detection unit. The second detection unit is required only to detect the position of a pinch roll outlet-side first tail end 302 and a pinch roll outlet-side second tail end 303 of the finished hot rolled steel strip 300, which is formed by finish rolling the rough hot rolled steel strip 204 after cropping and then fed to the pinch roll 105, which is a PR in a winder. Therefore, the second detection unit must be installed behind the pinch roll 105 outlet. For example, the second detection unit may be a laser meter 106 including a first laser meter 161 and a second laser meter 162, or may be a laser meter 106 further including a third laser meter. The second detection unit may also be an area sensor.

[0072] <About the calculation section> The tail end stop position control device for a hot rolled steel strip according to this embodiment includes a calculation unit. The calculation unit calculates a tail end correction amount Y for correcting the position of the tail end of the finish hot rolled steel strip 300. The calculation unit calculates the tail end correction amount Y for correcting the position of the tail end of the finish hot rolled steel strip 300 based on data relating to the rough hot rolled steel strip 200 detected and transmitted by the first detection unit and data relating to the finish hot rolled steel strip 300 detected and transmitted by the second detection unit. The calculation unit includes one or more processors, such as a general-purpose processor or a dedicated processor specialized for a specific process.

[0073] <About the position control unit> The tail end stop position control device for a hot rolled steel strip according to this embodiment includes a position control unit. The position control unit corresponds to a tail end stop controller 107. The position control unit is not particularly limited as long as it can receive a pulse wave and transmit the pulse wave to the mandrel driving unit M. The position control unit receives the value of the tail end correction amount Y calculated by the calculation unit as a pulse wave. Thereafter, the position control unit transmits the pulse wave received as the value of the tail end correction amount Y to the mandrel driving unit M. The mandrel driving unit M transmits the pulse wave received as the value of the tail end correction amount Y transmitted from the position control unit to the mandrel 109. The mandrel 109 controls the stop position of the tail end of the finish hot rolled steel strip 300 by rotating and driving it based on the received pulse wave.

[0074] As described above, according to the invention relating to the third embodiment, even if the shape of the tail end portion of the hot-rolled steel strip for winding is irregular and shifted in the width direction of the hot-rolled steel strip, the stopping position of the tail end of the hot-rolled steel strip can be controlled by calculating the tail end correction amount.

[0075] [Fourth embodiment] A thin plate coil according to a fourth embodiment will now be described. The thin plate coil according to this embodiment is characterized in that it is manufactured by coiling a finished hot-rolled steel strip obtained using the stop position control device for the tail end of a hot-rolled steel strip according to the above embodiment. The thin plate coil according to this embodiment will be described below.

[0076] A thin coil produced by coiling a finished hot rolled steel strip obtained using the control device for the stop position of the tail end of a hot rolled steel strip according to the above embodiment is controlled so that all of the tail winding ends of the finished hot rolled steel strips 300 constituting the thin coil are located at fixed positions. That is, even when a plurality of thin coils are produced using the control device for the stop position of the tail end of a hot rolled steel strip according to the above embodiment, all of the tail winding ends of the finished hot rolled steel strips 300 constituting the plurality of thin coils are located at the same fixed position. Therefore, when the thin coil is unwound from the mandrel 109, the tail winding ends of the finished hot rolled steel strips 300 constituting the thin coil do not peel off from the thin coil and interfere with other equipment.

[0077] Furthermore, in the thin plate coil according to this embodiment, all of the tail winding ends of the finish hot rolled steel strips 300 constituting the thin plate coil are located at the same fixed position. Therefore, when the thin plate coil is transported to a coil yard, the tail winding ends of the finish hot rolled steel strips 300 constituting the thin plate coil do not peel off from the thin plate coil, and the thin plate coil can be transported efficiently while ensuring safety.

[0078] As described above, according to the invention of the fourth embodiment, all winding tail ends of the hot-rolled steel strips constituting the thin plate coil are controlled to be positioned at fixed positions, thereby ensuring safety when removing the thin plate coil from the mandrel and enabling the thin plate coil to be transported efficiently to the coil yard.

[0079] [Other embodiments] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various modifications can be made to the configuration and details of the present invention that are understandable to those skilled in the art within the technical scope of the present invention. Furthermore, systems or devices that combine the separate features included in each embodiment in any manner are also included in the technical scope of the present invention. [Example]

[0080] The effects of the present invention will be specifically explained below based on examples, but the present invention is not limited to these examples.

[0081] (Example 1) The tail end of a finish hot-rolled steel strip constituting a thin coil was controlled by simulation using the method for controlling the tail end stop position of a hot-rolled steel strip according to the present invention. The results of the simulation of the control of the tail end of a finish hot-rolled steel strip obtained in Example 1 are shown in Table 1 and Figure 5(a).

[0082] (Comparative Example 1) A method for controlling the coiling of a hot-rolled steel strip proposed as a conventional technique (JP 2013-94798 A) was applied to simulate the control of the tail end of a finish hot-rolled steel strip constituting a thin coil under the same conditions as in Example 1. The results of the simulation of the control of the tail end of the finish hot-rolled steel strip obtained in Comparative Example 1 are shown in Table 1 and Figure 5(b).

[0083] [Table 1]

[0084] 5(a)-(b), the simulation results for controlling the tail end of the finish hot rolled steel strip obtained in Example 1 show that the standard deviation of the stop angle of the tail end of the final finish hot rolled steel strip is greatly improved from 25 degrees to 15 degrees. As such, the method for controlling the stop position of the tail end of a hot rolled steel strip according to the present invention can precisely control the stop position of the tail end of a finish hot rolled steel strip. In other words, by adopting the method for controlling the stop position of the tail end of a hot rolled steel strip according to the present invention, the risk of the tail end of a thin coil made of a finish hot rolled steel strip interfering with other equipment can be reduced. [Industrial Applicability]

[0085] According to the method for controlling the stopping position of the tail end of a hot-rolled steel strip of the present invention, it is possible to control the tail ends of all the hot-rolled steel strips constituting a thin coil to a fixed position, which contributes to the development of the steelmaking industry and is extremely useful industrially. [Explanation of symbols]

[0086] 100 Thin plate coil production line 101 Roughing mill 102 Two-dimensional shape measuring meter 103 Cropshire 104 Finishing Mill 105 Pinch roll (PR inside winding machine) 106 Laser Meter 161 First Laser Meter 162 Second Laser Meter 107 Tail end stop controller 108 Hot Run Table 181 Facility Center Line 109 Mandrel M Mandrel drive unit 200 Rough hot-rolled steel strip 201 Tail end central recess (rough hot rolled steel strip) 202 Left convex part 203 Right side convex part 204 Rough hot rolled steel strip after crop cutting 205 1st cut tail end 206 2nd cutting tail end 300 Finished Hot Rolled Steel Strip 301 Tail end central recess (finish hot rolled steel strip) 302 Pinch roll exit first tail end 303 Pinch roll exit side second tail end 304 Laser meter distance α 305 Laser detection difference distance β

Claims

1. 1. A method for controlling a stop position of a tail end of a finished hot rolled steel strip when the finished hot rolled steel strip is wound around a winding section having a mandrel to form a thin coil, comprising: a first step of detecting a two-dimensional shape of the tail end of the rough hot rolled steel strip that has been rough rolled, and detecting the position of a central recess at the tail end of the rough hot rolled steel strip and the positions of a first cut tail end and a second cut tail end of the rough hot rolled steel strip that have been formed by cropping convex portions formed adjacent to the left and right of the central recess using a two-dimensional shape meter; a second step of detecting, by a first laser meter, the position of a first tail end portion on the pinch roll outlet side corresponding to the first cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side after finish rolling the rough hot rolled steel strip after the crop cutting to form a finished hot rolled steel strip and then fed to a pinch roll, and detecting, by a second laser meter, the position of a second tail end portion on the pinch roll outlet side corresponding to the second cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side; a first detection position of a first tail end portion on the outlet side of the pinch roll detected by the first laser meter; a third step of calculating a tail end correction amount for correcting the position of the tail end of the finish hot rolled steel strip based on a laser distance and a laser detection difference distance formed between the first detection position and a second detection position of the second tail end portion on the pinch roll outlet side by the second laser meter; a fourth step of controlling the stop position of the tail end of the finish hot rolled steel strip based on the tail end correction amount.

2. A method for controlling the stop position of the tail end of a hot rolled steel strip as described in claim 1, characterized in that the position of the first tail end on the pinch roll outlet side corresponding to the first cut tail end of the finished hot rolled steel strip and the position of the second tail end on the pinch roll outlet side corresponding to the second cut tail end are detected by an area sensor capable of measuring the width direction of the finished hot rolled steel strip.

3. A control device for controlling a stop position of a tail end of a finished hot rolled steel strip when the finished hot rolled steel strip is wound by a winding section having a mandrel to form a thin coil, comprising: a first detection unit that detects a two-dimensional shape of the tail end of the rough hot rolled steel strip that has been rough rolled, and detects the position of a central recess at the tail end of the rough hot rolled steel strip and the positions of a first cut tail end and a second cut tail end of the rough hot rolled steel strip that have been formed by cropping convex portions formed adjacent to the left and right of the central recess using a two-dimensional shape meter; a second detection unit that detects, by a first laser meter, the position of a first tail end portion on the pinch roll outlet side corresponding to the first cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side after finish rolling the rough hot rolled steel strip after the crop cutting to form a finished hot rolled steel strip and then sent to the pinch roll; and that detects, by a second laser meter, the position of a second tail end portion on the pinch roll outlet side corresponding to the second cut tail end portion of the finished hot rolled steel strip that is output from the pinch roll outlet side. a third detection unit that calculates a tail end correction amount for correcting the position of the tail end of the finish hot rolled steel strip based on a first detection position of a first tail end portion on the pinch roll outlet side by the first laser meter, and a laser distance and a laser detection difference distance formed between the first detection position and a second detection position of a second tail end portion on the pinch roll outlet side by the second laser meter; a position control unit that controls the stop position of the tail end of the finish hot rolled steel strip based on the tail end correction amount.

4. A thin coil manufactured by the tail end stop position control device for a hot rolled steel strip according to claim 3.

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