MEANDERING CONTROL METHOD, MEANDERING CONTROL APPARATUS, AND MANUFACTURING METHOD FOR STEEL SHEET
20250187059 ยท 2025-06-12
Assignee
Inventors
- Shinichiro Aoe (Tokyo, JP)
- Masashi OKA (Tokyo, JP)
- Ryota HOSOYA (Tokyo, JP)
- Tetsuya ARAKAWA (Tokyo, JP)
- Yukihiro MATSUBARA (Tokyo, JP)
Cpc classification
B21B39/14
PERFORMING OPERATIONS; TRANSPORTING
B21B37/28
PERFORMING OPERATIONS; TRANSPORTING
B21B2263/02
PERFORMING OPERATIONS; TRANSPORTING
International classification
B21B37/68
PERFORMING OPERATIONS; TRANSPORTING
B21B39/14
PERFORMING OPERATIONS; TRANSPORTING
B21B37/28
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A meandering control method for a steel sheet, the method includes: a measurement step of measuring an out-of-plane deformation amount of the steel sheet on an upstream side of a steering device that changes a conveyance direction of the steel sheet; a calculation step of calculating an average curvature of the steel sheet using the out-of-plane deformation amount of the steel sheet measured in the measurement step; and a control step of calculating an off-center amount of the steel sheet in the steering device using the average curvature of the steel sheet calculated in the calculation step, and controlling a winding position of the steel sheet relative to the steering device based on the calculated off-center amount.
Claims
1. A meandering control method for a steel sheet, the method comprising: a measurement step of measuring an out-of-plane deformation amount of the steel sheet on an upstream side of a steering device that changes a conveyance direction of the steel sheet; a calculation step of calculating an average curvature of the steel sheet using the out-of-plane deformation amount of the steel sheet measured in the measurement step; and a control step of calculating an off-center amount of the steel sheet in the steering device using the average curvature of the steel sheet calculated in the calculation step, and controlling a winding position of the steel sheet relative to the steering device based on the calculated off-center amount.
2. The meandering control method for the steel sheet according to claim 1, wherein the measurement step includes a step of measuring the out-of-plane deformation amount of the steel sheet on a delivery side of a cutting device installed on the upstream side of the steering device, the cutting device being configured to cut an end portion of the steel sheet in a width direction.
3. A meandering control apparatus for a steel sheet, the apparatus comprising: a steering device that changes a conveyance direction of the steel sheet; a measurement device that measures an out-of-plane deformation amount of the steel sheet on an upstream side of the steering device; a position adjustment device that adjusts a winding position of the steel sheet relative to the steering device; and a control device that controls the position adjustment device, wherein the control device calculates an average curvature of the steel sheet using the out-of-plane deformation amount of the steel sheet that is measured by the measurement device, calculates an off-center amount of the steel sheet in the steering device using the calculated average curvature of the steel sheet, and controls the position adjustment device based on the calculated off-center amount.
4. The meandering control apparatus for the steel sheet according to claim 3, wherein the measurement device is installed on a delivery side of a cutting device installed on the upstream side of the steering device, the cutting device being configured to cut an end portion of the steel sheet in a width direction.
5. A manufacturing method for a steel sheet, the method comprising: a storage step of storing the steel sheet in a looper device while suppressing the meandering of the steel sheet using the method of controlling the meandering of the steel sheet according to claim 1; and a cold rolling step of cold-rolling the steel sheet stored in the looper device.
6. A manufacturing method for a steel sheet, the method comprising: a storage step of storing the steel sheet in a looper device while suppressing the meandering of the steel sheet using the method of controlling the meandering of the steel sheet according to claim 1; and an annealing step of annealing the steel sheet stored in the looper device.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0015]
[0016]
[0017]
[0018]
[0019]
DESCRIPTION OF EMBODIMENTS
[0020] Hereinafter, a meandering control method, a meandering control apparatus, and a manufacturing method for a steel sheet according to an embodiment of the present invention will be described with reference to the drawings.
[Concept]
[0021] First, a concept of the present invention will be described.
[0022] A shape defect of a steel sheet occurs mainly due to widthwise nonuniformity of elongation in the longitudinal direction in a rolling process. The shape defect of the steel sheet is superposition such as bending (one-side elongation) and edge wave/center buckle, and the shape defect that most greatly affects the meandering of the steel sheet is bending. In particular, in the case of a thin plate, out-of-plane deformation derived from bending disappears when the thin plate is formed into a cut plate, and it becomes difficult to measure bending. On the other hand, the edge wave/center buckle can be measured because the out-of-plane deformation remains even in the cut plate.
[0023] If the shape of the steel sheet is a curved surface shape in which the cross section in the width direction is a straight line, geometric definition of a curvature of the bending is described as in the following Mathematical Formula (1). In Mathematical Formula (1), x represents a longitudinal position of the steel sheet, v represents displacement of the steel sheet in the width direction from the center position of the steel sheet in the width direction, w represents displacement of the steel sheet in the vertical direction from the center position of the steel sheet in the width direction, and represents a twist angle of the steel sheet.
[0024] Since it is difficult to observe the curvature shown in Mathematical Formula (1), the bending of the steel sheet in the longitudinal direction is considered as an average value (average bending), and an average curvature K is defined as in Mathematical Formula (2) shown below. In Mathematical Formula (2), L represents a length of the steel sheet for averaging.
[0025] Accordingly, by substituting Mathematical Formula (1) into Mathematical Formula (2), the average curvature K is expressed as the following Mathematical Formula (3). The first term on the right side of Mathematical Formula (3) is an amount observed as meandering or skewing of the steel sheet, and the second term on the right side is an amount observed as out-of-plane deformation of the steel sheet. From Mathematical Formula (3), it can be seen that, even if only the meandering of the steel sheet is observed, the bending (average curvature K) of the steel sheet deeply related to the meandering of the steel sheet is not found. On the other hand, if meandering of the steel sheet does not occur, a value of the first term on the right side becomes zero, so that the average curvature K can be obtained from an observation amount of the out-of-plane deformation (second term on the right side). In a thin plate, when meandering occurs, the out-of-plane deformation of the thin plate is often accompanied.
[0026] When the twist angle of the steel sheet is small, Mathematical Formula (3) can be approximated as the following Mathematical Formula (4), and Mathematical Formula (4) can be transformed as the following Mathematical Formula (5).
[0027] When the twist angle of the steel sheet is small, the deflection W of the steel sheet can be expressed by the following Mathematical Formula (6). In Mathematical Formula (6), y represents the position of the steel sheet in the width direction.
[0028] Further, a length l (x, y) of the steel sheet along the bent curved surface can be expressed by the following Mathematical Formula (7).
[0029] Further, an elongation difference rate .sub.1 (x, y) of the steel sheet can be defined as the following Mathematical Formula (8).
[0030] In Mathematical Formula (8), l.sub.0 (x) represents the average length of the steel sheet in the width direction, and is expressed as the following Mathematical Formula (9). In Mathematical Formula (9), b represents the sheet width of the steel sheet.
[0031] Therefore, by substituting Mathematical Formula (6) and Mathematical Formula (7) into Mathematical Formula (9), Mathematical Formula (10) shown below is obtained.
[0032] When the deflection W and the twist angle of the steel sheet are small, Mathematical Formula (10) can be approximated as Mathematical Formula (11) shown below, and Mathematical Formula (12) shown below is obtained by deforming Mathematical Formula (11).
[0033] When Mathematical Formula (6), Mathematical Formula (7), and Mathematical Formula (12) are substituted into Mathematical Formula (8), the elongation difference rate .sub.1 (x, y) of the steel sheet is expressed by the following Mathematical Formula (13).
[0034] The curvature K.sub.1 of the average bending converted from the elongation difference rate .sub.1 (x, y) of the steel sheet is defined by the following Mathematical Formula (14).
[0035] By substituting Mathematical Formula (13) into Mathematical Formula (14), the following Mathematical Formula (15) is obtained.
[0036] Therefore, since Mathematical Formula (15) corresponds to the second term on the right side of Mathematical Formula (5), Mathematical Formula (5) can be modified as Mathematical Formula (16) shown below.
[0037] According to the above description, when the meandering of the steel sheet does not occur and the first term on the right side of Mathematical Formula (16) becomes zero, it can be seen that the average curvature K of the average bending can be obtained from the curvature K.sub.1. The curvature K.sub.1 can be calculated by substituting measured values of the out-of-plane deformation amount of the steel sheet and the gradient thereof into Mathematical Formula (14). Therefore, in the present invention, the out-of-plane deformation amount of the steel sheet and the gradient thereof are measured at a position at which the meandering of the steel sheet does not occur, the average curvature K of the steel sheet is calculated from the measured value, the off-center amount of the steel sheet in the steering device (the positional deviation direction and positional deviation amount of the center position in width direction of the steel sheet relative to the center position in the width direction of the steering device when the steel sheet reaches the steering device) is calculated from the calculated average curvature K, and the winding position of the steel sheet relative to the steering device is controlled based on the calculated off-center amount. The same control may be performed by measuring the meandering amount and the out-of-plane deformation amount of the steel sheet at a position at which the meandering of the steel sheet occurs, and calculating the average curvature K of the steel sheet using the measured meandering amount and out-of-plane deformation amount of the steel sheet. Accordingly, it is possible to suppress meandering of a steel sheet having a shape defect. In addition, by manufacturing the steel sheet using such meandering control method, it is possible to suppress the meandering of the steel sheet having the shape defect and to manufacture a steel sheet having a good yield.
[0038] Hereinafter, a description will be given as to a meandering control method, a meandering control apparatus, and a manufacturing method for a steel sheet according to an embodiment of the present invention, which is conceived based on the above concept. Note that the out-of-plane deformation amount is one of indices indicating bending and one-side elongation of a steel sheet S. As a method of measuring the out-of-plane deformation amount, methods illustrated in
[Configuration of Manufacturing Line]
[0039] First, with reference to
[0040]
[0041]
[0042] A second steering roll #2STR also having a deflector function is disposed on the downstream side of the looper car #1LP car. The steering roll #2STR includes the CPC meandering control device. On the downstream side of the steering roll #2STR, a looper car #2LP car including a third deflector roll is disposed. The looper car #2LP car adjusts the length of the steel sheet S between the rolls by moving in the left-right direction of the drawing. A third steering roll #3STR also having a deflector function is disposed on the downstream side of the looper car #2LP car. The steering roll #3STR includes the CPC meandering control device.
[0043] Between the deflector roll #1DEF and the looper car #1LP car and between the steering roll #2STR and the looper car #2LP car, support rolls that support the weight of the steel sheet S are disposed at a pitch of 2.5 m. Between the looper car #1LP car and the steering roll #2STR and between the looper car #2LP car and the steering roll #3STR, separator rolls having a function of supporting the weight of the steel sheet S and opening and closing when the steel sheet S passes through the looper car are installed at a pitch of 15 m. Although not illustrated, a guide vertical roll is installed at a predetermined pitch in the vicinity of the support roll for suppressing meandering.
[Configuration of Meandering Control Apparatus for Steel Sheet]
[0044] Next, a configuration of the meandering control apparatus for the steel sheet according to the embodiment of the present invention will be described with reference to
[0045] As illustrated in
[0046] The measurement device 11 is configured with a profilometer such as a three-dimensional laser scanner, and is disposed on the upstream side of a steering device that changes a conveyance direction of the steel sheet. Specifically, in the present embodiment, the measurement device 11 is disposed on the downstream side of the cutting device 1 and on the upstream side of the looper device 2 (steering roll). The measurement device 11 measures shape data of the steel sheet including the out-of-plane deformation amount of the steel sheet, and outputs an electric signal indicating the measured shape data to the control device 13. The location of the measurement device 11 is not limited to the position on the downstream side of the cutting device 1 and on the upstream side of the looper device 2, and may be disposed at any position as long as the steel sheet does not meander or the meandering amount of the steel sheet can be regarded as zero. For example, the measurement device 11 may be disposed at a position at which the meandering amount of the steel sheet has a size that does not affect the measurement of the shape data of the steel sheet (for example, the meandering amount of the steel sheet in the width direction is within 20 mm). Further, when the cutting device 1 is not disposed, the measurement device 11 may be disposed on the upstream side of the looper device 2.
[0047] The position adjustment device 12 adjusts the winding position of the steel sheet relative to the steering roll in the looper device 2 according to a control signal output from the control device 13. An operator may manually adjust the winding position of the steel sheet relative to the steering roll.
[0048] The control device 13 is configured by an information processing device such as a computer, and controls the entire operation of the meandering control apparatus for the steel sheet by executing a computer program stored in advance. In the present embodiment, the control device 13 calculates an average curvature of the steel sheet using the out-of-plane deformation amount of the steel sheet measured by the measurement device 11, calculates an off-center amount of the steel sheet in the steering roll using the calculated average curvature of the steel sheet, and controls the position adjustment device 12 based on the calculated off-center amount.
[0049] As is apparent from the above description, the meandering control apparatus for the steel sheet according to the embodiment of the present invention measures the out-of-plane deformation amount of the steel sheet on the upstream side of the steering device that changes the conveyance direction of the steel sheet, calculates the average curvature of the steel sheet using the measured out-of-plane deformation amount of the steel sheet, calculates the off-center amount of the steel sheet in the steering device using the calculated average curvature of the steel sheet, and controls the winding position of the steel sheet relative to the steering device based on the calculated off-center amount. Accordingly, it is possible to suppress meandering of a steel sheet having a shape defect. In addition, by manufacturing the steel sheet using such meandering control method, it is possible to suppress the meandering of the steel sheet having the shape defect and to manufacture a steel sheet having a good yield.
First Example
[0050] In the present example, whether there is a defect in a steel sheet was evaluated when meandering control according to the present invention was performed (example) and when the meandering control according to the present invention was not performed (comparative example and reference example) on a plurality of steel sheets having different shapes. The evaluation results are shown in Table 1 below. In the example, the winding position of the steel sheet relative to the steering roll #1STR illustrated in
TABLE-US-00001 TABLE 1 Edge wave/center Off- Sheet Line buckle center Whether width width Bending (elongation Meandering amount there is (m) (m) (1/m) difference rate) amount (m) (m) defect Remarks 1.0 1.65 0 0 0 0 No Reference example 1.3 1.65 0 0 0 0 No Reference example 1.0 1.65 0.005 0 0 0 No Reference example 1.1 1.65 0.005 0 0 0 No Reference example 1.2 1.65 0.005 0 0 0 No Reference example 1.3 1.65 0.005 0 0 0 Yes Comparative example 1.3 1.65 0.005 0 0 0.05 No Example 1.3 1.65 0.005 0 0 0 Yes Comparative example 1.3 1.65 0.005 0 0 0.05 No Example 1.3 1.65 0.005 0.002 (edge) 0 0 No Comparative example 1.3 1.65 0.005 0.002 (edge) 0 0.05 No Example 1.3 1.65 0.005 0.002 (center) 0 0 Yes Comparative example 1.3 1.65 0.005 0.002 (center) 0 0.05 No Example 1.0 1.45 0 0 0 0 No Reference example 1.1 1.45 0 0 0 0 No Reference example 1.0 1.45 0.005 0 0 0 No Reference example 1.2 1.45 0.005 0 0 0 Yes Comparative example 1.2 1.45 0.005 0 0 0.05 No Example
Second Example
[0051] In the present example, a relationship between the maximum bending of a joint portion of the steel sheet and occurrence of defects was evaluated. The evaluation results are illustrated in
[0052] Although the embodiments to which the invention made by the present inventors is applied have been described above, the present invention is not limited by the description and drawings configuring a part of the disclosure of the present invention according to the present embodiments. That is, other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the present embodiment are all included in the scope of the present invention.
INDUSTRIAL APPLICABILITY
[0053] According to the present invention, it is possible to provide a meandering control method and a meandering control apparatus for a steel sheet capable of suppressing meandering of the steel sheet having a shape defect. Further, according to the present invention, it is possible to provide a manufacturing method for the steel sheet capable of manufacturing the steel sheet having a good yield by suppressing meandering of the steel sheet having the shape defect.
REFERENCE SIGNS LIST
[0054] 1 CUTTING DEVICE [0055] 2 LOOPER DEVICE [0056] 3 COLD ROLLING MILL [0057] 4 ANNEALING FURNACE [0058] 11 MEASUREMENT DEVICE [0059] 12 POSITION ADJUSTMENT DEVICE [0060] 13 CONTROL DEVICE [0061] S STEEL SHEET