Rolling mill and metal plate rolling method

Abstract

The rolling mill includes: a roller for rolling a metal plate, which is displaceable in the axial direction and has a tapered portion at an end portion in the axial direction; and a heating portion configured to heat the tapered portion and form a radially protruding bulge in the tapered portion.

Description

Technical Field

[0001] The present disclosure relates to a rolling mill and a method for rolling a metal plate. Background Art

[0002] When rolling a metal plate using a rolling mill, depending on the rolling conditions, the plate thickness at the end portions in the plate width direction may become thinner than other portions, which is called edge drop. The occurrence of edge drop may lead to a decrease in yield, so research has been conducted to suppress edge drop.

[0003] For example, Patent Document 1 states that a tapered portion is provided at the end of a working roll of a rolling mill, and the working roll is shifted in the axial direction so that the tapered portion is located at the end of the rolled piece in the width direction, thereby suppressing edge thinning. Patent Document 1 also states that the end of the rolled piece in the plate width direction is heated or cooled, thereby suppressing edge thinning and making the cross-sectional profile of the rolled piece flat.

[0004] Patent Document 2 does not aim to suppress edge thinning, but it states that: the area at the end of the working roll that contacts the end of the steel plate (rolled product) is heated to form an expansion portion, thereby increasing the reduction rate of the end of the steel plate during cold rolling, thereby suppressing the occurrence of edge cracks.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 60-170508

[0008] Patent Document 2: Japanese Patent No. 6152837 Summary of the invention

[0009] Problems to be solved by the invention

[0010] In addition, it is considered that by increasing the axial displacement of the work rolls having tapered portions at the axial ends, the axial range (or the range in the sheet width direction) of the gap between the rolls can be adjusted to be larger, so that the edge thinning can be controlled with better accuracy. On the other hand, if the displacement of the work rolls is increased, the sheet thickness is likely to increase locally at the axial position where the gap between the rolls increases (edge ​​up), and in this case, the tension in the rolling direction (the direction in which the rolled product travels) changes abruptly at the ends in the sheet width direction (edge ​​tightness), which may cause sheet breakage.

[0011] In this regard, in the rolling mill described in Patent Document 1, it is not considered to suppress the above-mentioned edge thickening and plate breakage caused by edge tension, so it is difficult to increase the displacement of the work roll. Therefore, the effect of suppressing edge thinning is limited. In addition, in the rolling mill described in Patent Document 2, it is believed that the generation of edge cracks in the rolled product is suppressed by providing an expansion portion at the end of the work roll, but on the other hand, the generation of edge thinning is promoted.

[0012] In view of the above circumstances, an object of at least one embodiment of the present invention is to provide a rolling mill and a metal plate rolling method that can effectively suppress edge ironing.

[0013] Solutions to Solve Problems

[0014] A rolling mill according to at least one embodiment of the present invention includes:

[0015] a roller for rolling a metal plate, which is displaceable in an axial direction and has a tapered portion at an end portion in the axial direction; and

[0016] The heating portion is configured to heat the tapered portion to form an expanded portion protruding in a radial direction on the tapered portion.

[0017] Effects of the Invention

[0018] According to at least one embodiment of the present invention, a rolling mill and a metal plate rolling method are provided that are capable of effectively suppressing edge thinning. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic configuration diagram of a rolling mill according to one embodiment.

[0020] Figure 2 Observe in the conveying direction of the metal plate Figure 1 The figure obtained by the rolling stand shown.

[0021] Figure 3 This is a schematic configuration diagram of a rolling mill according to one embodiment.

[0022] Figure 4 This is a diagram schematically showing the vicinity of the end portions of the work rolls of a rolling mill according to one embodiment.

[0023] Figure 5 This is a schematic configuration diagram of a rolling mill control device according to one embodiment.

[0024] Figure 6 This is a schematic diagram for explaining the control of edge ironing in a rolling mill according to one embodiment.

[0025] Figure 7 This is a flowchart of an example of control of shifting of work rolls according to one embodiment.

[0026] Figure 8 This is a flowchart of an example of control of the heating position of the heating unit according to one embodiment. DETAILED DESCRIPTION

[0027] Hereinafter, several embodiments of the present invention will be described with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples.

[0028] Figure 1 as well as Figure 3 Each of them is a schematic configuration diagram of a rolling mill according to an embodiment. Figure 2 It is viewed from the downstream side to the upstream side in the conveying direction of the metal plate. Figure 1 The figure obtained by the rolling stand shown. Figure 4 This is a diagram schematically showing the vicinity of the end portions of the work rolls of a rolling mill according to one embodiment. Figure 5 This is a schematic configuration diagram of a rolling mill control device according to one embodiment.

[0029] like Figure 1 as well as Figure 3 As shown in the figure, the rolling mill 1 includes at least one rolling stand 10. The rolling stand 10 includes a pair of working rolls 12A, 12B, a pair of intermediate rolls 18A, 18B, and a pair of backup rolls 22A, 22B, which are arranged so as to sandwich a metal plate 50 as a rolled product. In addition, the rolling stand 10 includes a pressing device (not shown; for example, a hydraulic cylinder) for applying a load to the pair of working rolls 12A, 12B to press down the metal plate 50.

[0030] like Figure 2 As shown, a pair of working rolls 12A and 12B are supported rotatably by bearings (not shown) housed in bearing boxes 16a and 16b, respectively. A pair of intermediate rolls 18A and 18B are supported rotatably by bearings (not shown) housed in bearing boxes 20a and 20b, respectively. A pair of support rolls 22A and 22B are supported rotatably by bearings (not shown) housed in bearing boxes 24a and 24b, respectively. The intermediate rolls 18A and 18B and the support rolls 22A and 22B are configured to support the working rolls 12A and 12B.

[0031] The work rolls 12A and 12B are connected to a motor (not shown) via a spindle (not shown) or the like, and the work rolls 12A and 12B are driven to rotate by the motor. When the metal plate 50 is rolled, the metal plate 50 is pressed down by the press device while the work rolls 12A and 12B are rotated by the motor, thereby generating friction between the work rolls 12A and 12B and the metal plate 50, and the metal plate 50 is fed to the exit side of the work rolls 12A and 12B by the friction.

[0032] like Figure 3 As shown, the rolling mill 1 may also include a plurality of rolling stands 10. Figure 3 In the illustrated exemplary embodiment, the rolling mill 1 includes a plurality of rolling stands 10A to 10D arranged at intervals along the conveying direction of the metal plate 50. In the rolling mill 1, the metal plate 50 is sequentially rolled at the rolling stands 10A to 10D.

[0033] In some embodiments, the work rolls 12A and 12B are configured to be displaceable in the axial direction. In some embodiments, the rolling mill 1 includes a roll driving unit 26 configured to displace the work rolls 12A and 12B in the axial direction. Figure 1 to Figure 3 In the illustrated exemplary embodiment, shift cylinders as roll driving units 26A and 26B are provided for the work rolls 12A and 12B, respectively, and the work rolls 12A and 12B can be moved in the axial direction by driving the shift cylinders.

[0034] like Figure 2 As shown in FIG. 1 , the work rolls 12A and 12B of some embodiments have a tapered portion 14 provided at the axial end 13. The tapered portion 14 has a shape in which the front end becomes narrower as it approaches the axial end of the work rolls 12A and 12B. Figure 2 As shown in the figure, the tapered portion 14 may be provided at the end of one side of the work roll 12A of the pair of work rolls 12A and 12B, and the tapered portion 14 may be provided at the end of the other work roll 12B on the opposite side. Alternatively, in some embodiments, the tapered portion 14 may be provided at both ends of the pair of work rolls 12A and 12B.

[0035] In some embodiments, the rolling stand 10 is provided with a heating unit 30 (30A, 30B) for heating the tapered portion 14. The heating unit 30 is configured to form a radially protruding expansion portion 15 (see Figure 4 ).

[0036] It should be noted that Figure 4 The figure is a schematic diagram showing the positional relationship between the work roll 12, the heating unit 30 and the metal plate 50 in the axial direction of the work roll 12, and is not a figure obtained by observing the rolling stand 10 from a specific direction. However, regarding the metal plate 50, a cross section perpendicular to the running direction of the metal plate 50 is shown.

[0037] The heating unit 30 is provided near the tapered portion 14 and is configured to heat a portion of the tapered portion 14 in the axial direction. When the work roll 12 rotates, the above-mentioned area of ​​the tapered portion 14 is heated in a circumferential shape by the heating unit 30, and as a result, a circumferential expansion portion 15 protruding in the radial direction is formed in this area due to the thermal expansion of the work roll 12.

[0038] It should be noted that in Figure 1 to Figure 3 In the embodiment, the heating unit 30 is located on the downstream side of the work roll 12 in the traveling direction of the metal sheet 50 , but in some embodiments, the heating unit 30 may be located on the upstream side of the work roll 12 .

[0039] Here, in Figure 4 In FIG. 5 , reference numeral 52 ′ indicates the shape of the surface of the metal sheet 50 when rolling is performed in a state where the expanded portion 15 is not formed in the tapered portion 14 of the work roll 12. Figure 4 In the figure, the straight line L1 indicates the position of the surface 52 at a predetermined position in the center of the metal plate 50 in the plate width direction, the straight line L2 indicates the position of the plate end 54 of the metal plate 50 in the plate width direction, and the straight line L3 indicates the position (plate end position) at which the edge thinning amount or edge thickening amount in the plate width direction is measured (described later). Figure 6 The same also applies to ).

[0040] It should be noted that the edge thinning amount or edge thickening amount of the metal plate 50 can be calculated as the difference between the plate thickness at a predetermined position in the center of the plate width direction of the metal plate 50 and the plate thickness at the above-mentioned measuring position. The above-mentioned predetermined position and the measuring position can be defined, for example, as a position at a predetermined distance from the plate end 54. In one example, the above-mentioned predetermined position is a position at a distance of 115 mm from the plate end 54 in the plate width direction, and the above-mentioned measuring position is a position at a distance of 15 mm from the plate end 54 in the plate width direction.

[0041] Conventionally, it is known that the edge thinning can be suppressed by axially displacing the work rolls provided with tapered portions at the axial ends thereof so that the width end of the rolled piece is located at the tapered portions for rolling. In addition, it is believed that by increasing the axial displacement of the work rolls having tapered portions, the axial range (or the range in the plate width direction) in which the gap (roller gap) between the pair of work rolls 12 can be adjusted becomes larger, so that the edge thinning can be controlled with better accuracy. On the other hand, in order to achieve the target edge thickening amount U A (Refer to Figure 4 ), if the displacement of the working roll is increased, then for example Figure 4As shown by the reference numeral 52' in the figure, the plate thickness tends to increase locally at the axial position where the gap between the rollers increases. In this case, the tension in the rolling direction (the direction of travel of the metal plate 50) sometimes changes abruptly at the ends in the width direction of the plate (edge ​​tension) and causes the plate to break.

[0042] On the other hand, according to the rolling mill 1 of the above-mentioned embodiment, the expansion portion 15 protruding in the radial direction is formed in the tapered portion 14 provided at the end portion 13 of the work roll 12 by the heating portion 30, so that Figure 4 As shown in FIG. 1 , the surface shape of the metal plate 50 becomes the shape shown by the reference numeral 52, and the expansion portion 15 suppresses the local increase of the plate thickness at the end 13 of the metal plate 50 in the plate width direction. As a result, it is possible to suppress a sudden change in tension (edge ​​tension) at the end 13 of the metal plate 50 and suppress plate breakage at the end 13, so that the displacement amount of the work roll 12 can be increased, and the edge thickening amount can be easily brought close to the target value U A Therefore, the edge thinning that may occur during the rolling of the metal plate 50 can be appropriately controlled and effectively suppressed, and the yield can be improved.

[0043] In some embodiments, the heating unit 30 is configured to be movable in the axial direction. In some embodiments, the rolling mill 1 has a heating unit driving unit (not shown) configured to move the heating unit 30 in the axial direction. In this case, by moving the heating unit 30 in the axial direction of the work roll 12, the heating position of the heating unit 30 on the tapered portion 14 can be changed. Therefore, the heating position can be appropriately adjusted, and the edge tension that may be generated in the metal plate 50 can be effectively suppressed.

[0044] In some embodiments, for example, Figure 4 As shown in the figure, the heating unit 30 is configured to form the expansion portion 15 at a position closer to the inside in the plate width direction than the plate end 54 in the plate width direction of the metal plate 50. It should be noted that in this specification, the direction from the plate end 54 toward the center of the metal plate 50 in the plate width direction is defined as the inside direction in the plate width direction, and the direction from the center toward the plate end 54 of the metal plate 50 in the plate width direction is defined as the outside direction in the plate width direction.

[0045] According to the above-described embodiment, the bulged portion 15 is formed at a portion of the tapered portion 14 that is inside the position of the plate end 54 in the plate width direction of the metal plate 50 (plate end position), so that edge tension that is likely to occur at a position inside the plate end 54 can be effectively suppressed. Therefore, the displacement amount of the work roll 12 can be increased, and edge thinning that may occur during rolling of the metal plate 50 can be more effectively suppressed.

[0046] In some embodiments, the heating unit 30 is configured to heat the cone portion 14 using at least one of an electromagnetic induction coil, a heat medium, and a laser beam.

[0047] According to the above embodiment, the cone portion is heated by an electromagnetic induction coil, a heat medium or a laser beam, so it is easy to locally heat the cone portion 14. Therefore, the position and range of forming the expansion portion 15 in the cone portion 14 can be adjusted with good accuracy, thereby effectively suppressing the above-mentioned edge tension.

[0048] In some embodiments, for example, Figure 4 As shown in FIG. 1 , the heating unit 30 includes an electromagnetic induction coil 32 and an electromagnetic shield 34. The electromagnetic shield 34 is configured to restrict a magnetic path through which the magnetic flux generated by the electromagnetic induction coil 32 flows. The electromagnetic shield 34 may be formed of a grounded conductor. Figure 4 In the illustrated exemplary embodiment, electromagnetic shielding members 34 are provided on both sides of the electromagnetic induction coil 32 in the axial direction of the work roll 12. Thus, the magnetic path described above is limited in the axial direction.

[0049] According to the above-mentioned embodiment, the electromagnetic shielding member 34 is used to limit the magnetic path through which the magnetic flux generated by the electromagnetic induction coil 32 flows, so it is easy to limit the heating range of the cone 14 by the electromagnetic induction coil 32. Therefore, the position and range of forming the expansion portion 15 in the cone 14 can be adjusted with more accuracy, thereby effectively suppressing the above-mentioned edge tension.

[0050] In the case of a tandem rolling mill 1 including a plurality of rolling stands 10 (see, for example, Figure 3 ), a heating unit 30 may be provided at least one of the rolling stands 10 located upstream of the most downstream rolling stand 10 among the plurality of rolling stands 10. Alternatively, a heating unit 30 may be provided at the most upstream rolling stand 10 among the plurality of rolling stands 10. Figure 3 In the illustrated exemplary embodiment, the heating unit 30 is provided in each of the rolling stand 10A and the rolling stand 10B among the rolling stands 10A to 10C located on the upstream side of the rolling stand 10D located on the most downstream side.

[0051] The edge thinning of the metal plate 50 is often a problem in cold rolling using a tandem rolling mill. In this regard, in the above-mentioned embodiment, the rolling stand 10 located on the upstream side among the plurality of rolling stands 10 is provided with a work roll 12 having a tapered portion 14 and capable of being displaced in the axial direction and a heating unit 30. That is, the above-mentioned work roll 12 and heating unit 30 are provided at the rolling stand 10 at a position where the temperature of the metal plate 50 is relatively high and relatively soft, so that, in particular, when cold rolling is performed, edge thickening can be effectively suppressed, thereby effectively suppressing edge thinning.

[0052] like Figure 1 as well as Figure 3 As shown, in some embodiments, the rolling mill 1 may also include a control device 90 for controlling the rolling mill 1. Figure 5 As shown, the control device 90 may also include: a heating control unit 92 for controlling the heating of the tapered portion 14 by the heating unit 30 ; and a roll control unit 94 for controlling the axial displacement of the work roll 12 .

[0053] The control device 90 may be configured to receive a signal indicating a detection result from a measuring device (for example, the plate end detection unit 40 or the plate thickness detection unit 48 described later) and perform control based on the detection result.

[0054] The control device 90 may also include a processor, a memory (RAM), an auxiliary storage unit, and an interface. The control device 90 receives signals from the above-mentioned measuring devices via the interface. The processor is configured to process the received signals. In addition, the processor is configured to process the program developed in the memory.

[0055] The processing contents in the control device 90 may be installed as a program executed by the processor and stored in the auxiliary storage unit. When the program is executed, the program is expanded in the memory. The processor reads the program from the memory and executes the instructions included in the program.

[0056] The heating control unit 92 is configured to determine the heating position of the heating unit 30 on the tapered portion 14 in the axial direction based on the plate end position in the plate width direction of the metal plate 50. The heating control unit 92 may also be configured to move the heating unit 30 so that the tapered portion 14 is heated at the heating position determined as described above.

[0057] The heating control unit 92 determines the heating position of the tapered portion 14 in the axial direction of the work roll 12 based on the plate end position of the metal plate 50, thereby enabling the heating position to be adjusted in accordance with the plate end position and effectively suppressing the above-mentioned edge tension even when the plate end position of the metal plate 50 changes.

[0058] The heating control unit 92 may be configured to determine the above-mentioned heating position based on the board end position detected by the board end detection unit 40. As the board end detection unit 40, for example, an edge position meter, a shape meter, or an edge thinning meter can be used.

[0059] The edge position meter may also be configured to detect the plate end position using radiation (e.g., X-rays, gamma rays). By using radiation, it is easy to miniaturize the edge position meter. Therefore, when it is easy to set the edge position meter near the rolling stand 10, or when the rolling mill 1 includes a plurality of rolling stands 10, it is easy to arrange the edge position meter between adjacent rolling stands 10.

[0060] The shape meter may be configured to measure the tension distribution in the plate width direction of the metal plate 50. The tension in the plate width direction of the metal plate 50 becomes a positive value at a position where the metal plate 50 exists, whereas it becomes zero at a position where the metal plate 50 does not exist. Therefore, the plate end position can be grasped based on the tension distribution in the plate width direction.

[0061] The edge thinning meter can also be configured to measure the plate thickness distribution within the plate width direction including the plate end. The plate thickness of the metal plate 50 in the plate width direction becomes a positive value at the position where the metal plate 50 exists, and on the contrary, becomes zero at the position where the metal plate 50 does not exist. Therefore, the plate end position can be grasped based on the plate thickness distribution in the plate width direction. In addition, the edge thinning meter can also be configured to detect the edge thinning amount of the metal plate 50 based on the above-mentioned plate thickness distribution.

[0062] In some embodiments, the plate end detector 40 is provided on the entry side of the work roll 12 in the traveling direction of the metal plate 50. In this case, the plate end position detected by the plate end detector 40 is fed forward, so that the heating position of the tapered portion 14 by the heater 30 can be appropriately controlled.

[0063] In some embodiments, the plate end detection unit 40 is provided on the exit side of the work roll 12 in the traveling direction of the metal plate 50. In this case, by feeding back the plate end position detected by the plate end detection unit 40, the heating position of the tapered portion 14 by the heating unit 30 can be appropriately controlled.

[0064] In some embodiments, the plate end detection unit 40 is provided between two adjacent rolling stands 10 in the traveling direction of the metal plate 50 among the plurality of rolling stands 10. In this case, by feeding back or feeding forward the plate end position detected by the plate end detection unit 40, it is possible to appropriately control the heating position of the cone portion 14 by the heating unit 30. In addition, compared with the case of detecting the plate end position at the entry side or exit side of the plurality of rolling stands 10, it is easy to make the plate end detection position close to the heating position, so it is easy to make the responsiveness of the control of the heating position good.

[0065] The roll control unit 94 is configured to determine the shift amount of the work roll 12 based on a parameter related to the thickness at the end portion in the sheet width direction of the metal sheet 50. For example, the roll control unit 94 may determine the shift amount of the work roll 12 based on the thickness distribution at the end portion in the sheet width direction of the metal sheet 50. Alternatively, the roll control unit 94 may determine the shift amount of the work roll 12 based on the edge thinning amount of the metal sheet 50.

[0066] The roll control unit 94 may be configured to control the roll driving unit 26 (shift cylinder) so that the work roll 12 moves by the shift amount determined as described above.

[0067] The roll control unit 94 may be configured to determine the displacement amount of the work roll 12 based on the above-mentioned parameter related to the thickness detected by the plate thickness detection unit 48. As the plate thickness detection unit 48, for example, an edge ironing meter can be used.

[0068] The plate thickness detector 48 may be provided at the entry side or exit side of the work roll 12 in the advancing direction of the metal plate. In this case, the displacement of the work roll 12 can be appropriately controlled by feeding forward or feeding back the parameters related to the plate thickness detected by the plate thickness detector 48.

[0069] exist Figure 1 In the illustrated exemplary embodiment, the rolling mill 1 includes an edge reduction gauge 42 provided on the entry side of the work rolls 12 , and an edge reduction gauge 44 and an edge position gauge 46 provided on the exit side of the work rolls 12 .

[0070] exist Figure 3 In the exemplary embodiment shown, the rolling mill 1 includes: an edge thinning gauge 42, which is arranged on the entry side of multiple rolling stands 10A to 10D; an edge thinning gauge 44, which is arranged on the exit side of multiple rolling stands 10A to 10D; and an edge position gauge 46, which is arranged between adjacent rolling stands 10B and 10C among the multiple rolling stands 10.

[0071] exist Figure 1 as well as Figure 3 In the illustrated exemplary embodiment, the heating control unit 92 is configured to determine the heating position of the tapered portion 14 by the heating unit 30 based on the detection result of at least one of the edge thinning meter 42, the edge thinning meter 44, and the edge position meter 46. In addition, the roll control unit 94 is configured to determine the shift amount of the work roll 12 based on the detection result of at least one of the edge thinning meter 42 and the edge thinning meter 44.

[0072] Next, refer to Figure 6 to Figure 8 Several embodiments of the control of edge ironing in the rolling mill 1 will be described. Figure 6This is a schematic diagram for explaining the control of edge ironing in a rolling mill according to one embodiment. Figure 7 This is a flowchart of an example of control of the shift of the work roll 12. Figure 8 1 is a flowchart of an example of the control of the heating position of the cone portion 14 by the heating unit 30. Figure 6 The straight line L4 in FIG. 1 represents the heating position of the tapered portion 14 by the heating unit 30 in the plate width direction.

[0073] In one embodiment, based on Figure 7 In the flowchart shown, the roll control unit 94 controls the displacement of the work roll 12. First, the edge reduction amount Ed is detected by an edge reduction gauge (plate thickness detection unit 48) provided on the entry side or exit side of the work roll 12 (step S102).

[0074] Here, the edge thinning amount Ed of the metal plate 50 is the difference between the plate thickness at a predetermined position in the center of the metal plate 50 and the thickness from the plate end ( Figure 6 The measured position P is obtained by separating the measured position P0 inward by a predetermined distance in the width direction of the plate. Ed (Refer to Figure 6 If the direction from the metal plate 50 toward the work roll 12 in the plate thickness direction is defined as the positive direction, the position coordinate of the surface of the metal plate 50 in the plate thickness direction at the above-mentioned predetermined position is set as H0, and the above-mentioned measurement position P is set as Ed The position coordinate of the surface of the metal plate 50 in the plate thickness direction is set to H, and the edge thinning amount Ed is represented by (H-H0). It should be noted that in this description, when the edge thinning amount Ed is positive, it is a state where the plate thickness at the above-mentioned measuring position is larger than that of the central portion (a state where edge thickening occurs), and when the edge thinning amount Ed is negative, it is a state where the plate thickness at the above-mentioned measuring position is smaller than that of the central portion (a state where edge thinning occurs).

[0075] Next, the edge thinning amount Ed detected in step S102 and the target value Ed of the edge thinning amount are calculated. A The deviation is the edge thinning deviation ΔEd (step S104). Figure 6 In the figure, curve 105 indicates that the edge thinning amount is the target value Ed. A An example of the surface shape of the metal plate 50 when the measuring position P Ed The position coordinate of the surface of the metal plate 50 is H A It should be noted that the target value of edge thinning Ed A By (H A -H0) indicates that the edge thinning deviation ΔEd = (Ed-Ed A )=(HH A ) was established.

[0076] Next, it is determined whether the edge thinning deviation ΔEd calculated in step S104 is within the prescribed range (step S106). If the edge thinning deviation ΔEd is within the prescribed range (yes in step S106), there is no need to shift the work roll 12 in the axial direction, so the axial position of the work roll 12 is not changed, and the process returns to step S102 to continue detecting the edge thinning amount.

[0077] When the edge thickness deviation ΔEd is outside the predetermined range in step S106 (No in step S106 ), the shift amount of the work roll 12 is determined so that the edge thickness deviation ΔEd falls within the predetermined range (steps S108 to S112 ).

[0078] In step S106, when the edge thinning deviation ΔEd is outside the prescribed range (No in step S106), and the edge thinning deviation ΔEd is larger than the prescribed range (Yes in step S108; see Figure 6 The edge thinning deviation ΔEd is brought close to the prescribed range by shifting the work rolls 12 outward to reduce the gap between the rolls at the tapered portion 14 (step S110). Thus, the edge thinning can be appropriately controlled.

[0079] It should be noted that in Figure 6 In the figure, a curve 106 shows an example of the surface shape of the metal plate 50 when the edge thickening amount is relatively large. In this case, the measurement position P Ed The position coordinate of the surface of the metal plate 50 at the position is H1. In this case, the edge thinning deviation ΔEd is given by (H1-H A ) means that in (H1-H A ) is larger than the prescribed range, as described above, the work roll 12 is shifted outward in step S110.

[0080] On the other hand, in step S106, when the edge thinning deviation ΔEd is outside the prescribed range (No in step S106), and the edge thinning deviation ΔEd is smaller than the prescribed range (No in step S108; see Figure 6 The work roll 12 is displaced inward to expand the gap between the rolls at the tapered portion 14 (step S112), so that the edge thinning deviation ΔEd approaches the specified range. Thus, the edge thinning can be suppressed by increasing the plate thickness at the plate end.

[0081] It should be noted that in Figure 6 In the figure, a curve 107 shows an example of the surface shape of the metal plate 50 when the edge thinning amount is relatively large. In this case, the measurement position P Ed The position coordinate of the surface of the metal plate 50 at the position is H2. In this case, the edge thinning deviation ΔEd is given by (H2-HA ) means that in (H2-H A ) is smaller than the prescribed range, as described above, the work rolls 12 are shifted inwardly in step S110.

[0082] Here, a limit value (upper limit value) is set for the inward displacement amount of the work roll 12 in step S112. That is, in step S112, the work roll 12 is displaced inward within a range where the displacement amount of the work roll 12 does not exceed the limit value. The limit value is set to a value that does not cause plate breakage due to edge tension. The above limit value may also be set based on experience.

[0083] In one embodiment, based on Figure 8 The heating control unit 92 is used to control the heating position of the taper portion 14 by the heating unit 30. First, the plate end position ( Figure 6 The position of P0 at the position is detected (step S202).

[0084] Next, the axial position of the heating portion 30 is calculated (in one embodiment, the central position of the heating portion 30; Figure 6 P H The position of the plate end) is determined by measuring the deviation ΔWd between the plate end position detected in step S202 (step S204).

[0085] If the deviation ΔWd of the axial position calculated in step S204 is smaller than the prescribed range (No in step S206), it is determined that the heating position of the taper portion 14 by the heating unit 30 is within the appropriate range, and the process returns to step S202 to continue the detection of the plate end position. On the other hand, if the deviation ΔWd of the axial position calculated in step S204 is larger than the prescribed range (Yes in step S206), the heating position of the taper portion 14 by the heating unit 30 is determined so that the deviation ΔWd is within the prescribed range, and the heating unit 30 is moved in the axial direction to heat the heating position determined in this way (step S208).

[0086] The predetermined range of the deviation ΔWd in the plate width direction is set so that the heating position of the tapered portion 14 by the heating unit 30 is located within the axial position range where edge thickening may occur in the metal plate 50 in the rolling mill 1. The deviation ΔWd may also be based on the measurement position P of the edge thinning amount of the metal plate 50. Ed to set.

[0087] In this way, by adjusting the heating position of the tapered portion 14 by the heating unit 30, the expansion portion 15 can be formed at an appropriate position of the tapered portion 14, and the edge tension that may be generated in the metal plate 50 can be suppressed. As a result, the plate breakage at the end of the metal plate 50 caused by the edge tension can be suppressed, so the displacement amount of the work roll 12 can be increased. For example, Figure 7 The limiting value (upper limit value) of the inward displacement amount of the work roll 12 in step S112 of the flowchart is set larger. In this way, the displacement amount of the work roll 12 can be increased, and the edge thinning (edge ​​thinning amount and edge thickening amount) of the metal plate 50 can be appropriately controlled, so that the edge thinning that may occur during the rolling of the metal plate 50 can be effectively suppressed, and the yield rate can be improved.

[0088] Hereinafter, rolling mills and metal plate rolling methods according to several embodiments will be described in outline.

[0089] (1) A rolling mill according to at least one embodiment of the present invention includes:

[0090] a roller for rolling a metal plate (such as the above-mentioned working roll 12), which is displaceable in the axial direction and has a tapered portion at an end portion in the axial direction; and

[0091] The heating portion heats the tapered portion to form an expanded portion protruding in a radial direction on the tapered portion.

[0092] According to the structure of (1) above, the expansion portion protruding in the radial direction is formed by the tapered portion provided at the end of the roller in the heating portion, so that the edge tension of the end of the metal plate (rolled product) in the plate width direction can be suppressed. As a result, the plate fragmentation at the end of the metal plate caused by the edge tension can be suppressed, so the displacement of the roller can be increased. Therefore, the edge thinning that may occur during the rolling of the metal plate can be effectively suppressed, and the yield rate can be improved.

[0093] (2) In some embodiments, based on the structure of (1) above,

[0094] The heating unit is configured to heat the tapered portion using at least one of an electromagnetic induction coil, a heat medium, and a laser beam.

[0095] According to the structure of (2) above, the cone portion is heated by an electromagnetic induction coil, a heat medium or a laser beam, so that the cone portion can be locally heated. Therefore, the position and range of the expansion portion formed in the cone portion can be adjusted with good accuracy, thereby effectively suppressing the above-mentioned edge tension. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0096] (3) In some embodiments, based on the structure of (1) or (2),

[0097] The heating unit includes an electromagnetic induction coil and an electromagnetic shield for limiting a magnetic path through which a magnetic flux generated by the electromagnetic induction coil flows.

[0098] According to the structure of (3) above, the electromagnetic shielding member is used to limit the magnetic path for the flow of the magnetic flux generated by the electromagnetic induction coil, so it is easy to limit the heating range of the cone by the electromagnetic induction coil. Therefore, the position and range of the expansion portion formed in the cone can be adjusted with better accuracy, thereby effectively suppressing the above-mentioned edge tension. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0099] (4) In some embodiments, based on any one of the structures (1) to (3) above,

[0100] The heating portion is configured so that the expansion portion is formed at a position further inward in the plate width direction than an end of the metal plate in the plate width direction.

[0101] According to the structure of (4) above, the expansion portion is formed at a portion of the tapered portion that is closer to the inside than the end position of the metal plate in the plate width direction (plate end position), so that the edge tension that is likely to occur at the position closer to the inside than the plate end can be effectively suppressed. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0102] (5) In some embodiments, based on any one of the structures (1) to (4) above,

[0103] The rolling mill includes a heating control unit configured to be able to change the heating position by moving the heating unit in the axial direction.

[0104] According to the structure of (5) above, the heating position of the heating part on the tapered part can be changed in the axial direction of the roller, so by appropriately adjusting the heating position, the above-mentioned edge tension can be effectively suppressed. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0105] (6) In some embodiments, based on any one of the structures (1) to (5) above,

[0106] The rolling mill comprises:

[0107] a plate end detection unit configured to detect a plate end position of the metal plate in a plate width direction; and

[0108] The heating control unit is configured to determine a heating position of the tapered portion by the heating unit in the axial direction based on the detected plate end position.

[0109] According to the structure of (6), the heating position of the tapered portion in the axial direction of the roller is determined based on the plate end position of the metal plate. Therefore, even when the plate end position of the metal plate changes, the edge tension can be effectively suppressed by adjusting the heating position in accordance with the plate end position. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0110] (7) In some embodiments, based on the structure of (6) above,

[0111] The plate end detection portion is provided on an entry side of the roller in a traveling direction of the metal plate.

[0112] According to the structure of (7) above, the plate end position at the entrance side of the roller is detected, and thus the heating position of the heating unit can be appropriately controlled by feeding forward the detected position. Therefore, the above-mentioned edge tension can be effectively suppressed, thereby increasing the displacement of the roller and more effectively suppressing the edge thinning that may occur during the rolling of the metal plate.

[0113] (8) In some embodiments, based on the structure of (6),

[0114] The plate end detection portion is provided on an exit side of the roller in a traveling direction of the metal plate.

[0115] According to the structure of (8) above, the plate end position at the exit side of the roller is detected, and thus the heating position of the heating unit can be appropriately controlled by feeding back the detected position. Therefore, the edge tension mentioned above can be effectively suppressed, thereby increasing the displacement of the roller and more effectively suppressing the edge thinning that may occur during the rolling of the metal plate.

[0116] (9) In some embodiments, based on any one of the structures (6) to (8) above,

[0117] The rolling mill includes a plurality of rolling stands each including a roller for rolling the metal plate.

[0118] The heating unit is provided at least one of the plurality of rolling stands.

[0119] The plate end detection unit is provided between two rolling stands adjacent to each other in the traveling direction of the metal plate among the plurality of rolling stands.

[0120] According to the structure of (9) above, the plate end position between the plurality of rolling stands is detected, and thus the heating position of the heating section can be appropriately controlled by feeding back or feeding forward the detected position. In addition, compared with the case where the plate end position at the entry or exit side of the plurality of rolling stands is detected, it is easy to make the plate end detection position close to the heating position, and thus it is easy to make the control of the heating position responsive. Therefore, the above-mentioned edge tension can be effectively suppressed, thereby increasing the displacement of the roller and more effectively suppressing the edge thinning that may occur during the rolling of the metal plate.

[0121] (10) In some embodiments, based on any one of the structures (1) to (9) above,

[0122] The rolling mill comprises:

[0123] a plate thickness detection unit configured to detect a parameter related to the thickness of the metal plate at an end portion in a plate width direction; and

[0124] The roller control unit is configured to determine a displacement amount of the roller in the axial direction based on the detected parameter.

[0125] According to the structure of (10), the edge tension of the metal plate is suppressed by using the structure of (1), so that the plate breakage at the end of the metal plate can be suppressed, and thus the roller displacement can be determined to a larger value. Therefore, the roller displacement can be increased to effectively suppress the edge thinning that may occur during the rolling of the metal plate, and the yield rate can be improved.

[0126] (11) A metal plate rolling method according to at least one embodiment of the present invention includes:

[0127] A step of rolling a metal plate using a roller having a tapered portion at an end portion in an axial direction;

[0128] a step of displacing the roller in the axial direction; and

[0129] The step of heating the tapered portion to form a bulged portion protruding in a radial direction on the tapered portion.

[0130] According to the method of (11) above, by heating the tapered portion provided at the end of the roller, a radially protruding expansion portion is formed at the tapered portion, thereby suppressing edge tension at the end of the metal plate (rolled product) in the plate width direction. As a result, plate fragmentation at the end of the metal plate caused by edge tension can be suppressed, thereby increasing the displacement of the roller. Therefore, it is possible to effectively suppress edge thinning that may occur during the rolling of the metal plate, and to improve the yield rate.

[0131] (12) In some embodiments, based on the method of (11) above,

[0132] In the step of forming the bulged portion, the bulged portion is formed at a position further inward in the plate width direction than an end of the metal plate in the plate width direction.

[0133] According to the method of (12) above, the expansion portion is formed at a portion of the tapered portion that is closer to the inside than the end position of the metal plate in the plate width direction (plate end position), so that edge tension that is likely to occur at a position closer to the inside than the plate end can be effectively suppressed. Therefore, the displacement amount of the roller can be increased, and edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0134] (13) In some embodiments, based on the method of (11) or (12) above,

[0135] The rolling method comprises:

[0136] a step of detecting a plate end position of the metal plate in a plate width direction; and

[0137] A step of determining a heating position of the tapered portion in the axial direction based on the detected plate end position.

[0138] According to the method (13) above, the heating position of the tapered portion in the axial direction of the roller is determined based on the plate end position of the metal plate, so even if the plate end position of the metal plate changes, the edge tension can be effectively suppressed by adjusting the heating position in accordance with the plate end position. Therefore, the roller displacement can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0139] (14) In some embodiments, based on any one of the methods (11) to (13) above,

[0140] The rolling method includes the step of changing the heating position by moving a heating unit for heating the tapered portion in the axial direction.

[0141] According to the method (14) above, the heating position of the heating part on the tapered part can be changed in the axial direction of the roller, so by appropriately adjusting the heating position, the above-mentioned edge tension can be effectively suppressed. Therefore, the displacement of the roller can be increased, and the edge thinning that may occur during the rolling of the metal plate can be more effectively suppressed.

[0142] (15) In some embodiments, based on any one of the methods (11) to (14) above,

[0143] The rolling method comprises:

[0144] a step of detecting a parameter related to the thickness at the end portions of the metal plate in the plate width direction; and

[0145] A step of determining the displacement amount of the roller in the axial direction based on the detected parameter.

[0146] According to the method of (15), by suppressing the edge tension of the metal plate using the method of (11), it is possible to suppress the plate breakage at the end of the metal plate, so that the roller displacement can be determined to a larger value. Therefore, the roller displacement can be increased to effectively suppress the edge thinning that may occur during the rolling of the metal plate, and the yield rate can be improved.

[0147] As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It also includes the form which added deformation|transformation to the said embodiment, and the form which combined these forms suitably.

[0148] In this specification, expressions such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" that indicate relative or absolute configurations not only indicate strictly such configurations, but also indicate a state of relative displacement at an angle or distance with a tolerance or a degree that can achieve the same function.

[0149] For example, expressions such as “same”, “equal”, and “homogeneous” indicating a state in which things are equal not only indicate a state in which things are strictly equal, but also indicate a state in which there is a tolerance or a difference to the extent that the same function can be obtained.

[0150] In the present specification, expressions indicating shapes such as a quadrilateral shape and a cylindrical shape not only indicate shapes such as a quadrilateral shape and a cylindrical shape in a strict geometric sense, but also indicate shapes including concave-convex portions, chamfered portions, etc. within a range that can obtain the same effect.

[0151] In addition, in this specification, the expression “comprising”, “including” or “having” a component as a main expression is not an exclusive expression excluding the existence of other components.

[0152] Description of Reference Numerals

[0153] 1 Rolling mill

[0154] 10, 10A~10d rolling table

[0155] 12, 12A, 12B working rolls

[0156] 13 end

[0157] 14 Cone

[0158] 15. Expansion

[0159] 16a, 16b bearing box

[0160] 18A, 18B Intermediate roller

[0161] 20a, 20b bearing box

[0162] 22A, 22B support rollers

[0163] 24a, 24b bearing box

[0164] 26, 26A, 26B Roller drive unit

[0165] 30 Heating unit

[0166] 32 Electromagnetic induction coil

[0167] 34 Electromagnetic shielding parts

[0168] 40 Board end detection unit

[0169] 42 Edge Thinning Gauge

[0170] 44 Edge Thinning Gauge

[0171] 46 Edge position meter

[0172] 48 Plate Thickness Detection Department

[0173] 50 Metal Plate

[0174] 52 Surface

[0175] 54 Board end

[0176] 90 Control Device

[0177] 92 Heating control unit

[0178] 94 Roller control unit.

Claims

1. A rolling mill comprising a roller which is displaceable in an axial direction and has a tapered portion at an end portion in the axial direction, and is used for rolling a metal plate, wherein: The rolling mill comprises: a heating portion configured to heat a portion of the tapered portion in the axial direction to form an expansion portion in the tapered portion that protrudes in the radial direction relative to other regions of the tapered portion; an edge thinning meter configured to detect an amount of edge thinning of the metal plate; as well as a roller control unit configured to displace the roller in the axial direction based on the edge thinning amount detected by the edge thinning meter, The edge thinning amount is a difference between a plate thickness at a predetermined position in the center of the metal plate and a plate thickness at a measured position separated inwardly by a predetermined distance from a plate end of the metal plate in the axial direction.

2. The rolling mill according to claim 1, wherein: The heating unit is configured to heat the tapered portion using at least one of an electromagnetic induction coil, a heat medium, and a laser beam.

3. The rolling mill according to claim 1 or 2, wherein: The heating unit includes an electromagnetic induction coil and an electromagnetic shield for limiting a magnetic path through which a magnetic flux generated by the electromagnetic induction coil flows.

4. The rolling mill according to claim 1 or 2, wherein: The heating portion is configured so that the expansion portion is formed at a position further inward in the plate width direction than an end of the metal plate in the plate width direction.

5. The rolling mill according to claim 1 or 2, wherein: The rolling mill includes a heating control unit configured to change a heating position of the tapered portion in the axial direction by moving the heating unit in the axial direction.

6. The rolling mill according to claim 1 or 2, wherein: The rolling mill comprises: a plate end detection unit configured to detect a plate end position of the metal plate in a plate width direction; and The heating control unit is configured to determine a heating position of the tapered portion by the heating unit in the axial direction based on the detected plate end position.

7. The rolling mill according to claim 6, wherein: The plate end detection portion is provided on an entry side of the roller in a traveling direction of the metal plate.

8. The rolling mill according to claim 6, wherein: The plate end detection portion is provided on an exit side of the roller in a traveling direction of the metal plate.

9. The rolling mill according to claim 6, wherein: The rolling mill includes a plurality of rolling stands each including a roller for rolling the metal plate. The heating unit is provided at least one of the plurality of rolling stands. The plate end detection unit is provided between two rolling stands adjacent to each other in the traveling direction of the metal plate among the plurality of rolling stands.

10. The rolling mill according to claim 1 or 2, wherein: The rolling mill comprises: a plate thickness detection unit configured to detect a parameter related to the thickness of the metal plate at an end portion in a plate width direction; and The roller control unit is configured to determine a displacement amount of the roller in the axial direction based on the detected parameter.

11. A method for rolling a metal plate, comprising rolling the metal plate using a roller having a tapered portion at an end portion in an axial direction and displacing the roller in the axial direction, wherein: The metal plate rolling method comprises: A step of heating a portion of the tapered portion in the axial direction to form a bulged portion in the tapered portion that protrudes in the radial direction relative to other regions of the tapered portion; A detection step of detecting the amount of edge thinning of the metal plate; and a step of displacing the roller in the axial direction based on the edge thinning amount detected by the detecting step, The edge thinning amount is a difference between a plate thickness at a predetermined position in the center of the metal plate and a plate thickness at a measured position separated inwardly by a predetermined distance from a plate end of the metal plate in the axial direction.

12. The metal plate rolling method according to claim 11, wherein: In the step of forming the bulged portion, the bulged portion is formed at a position further inward in the plate width direction than an end of the metal plate in the plate width direction.

13. The metal plate rolling method according to claim 11 or 12, wherein: The metal plate rolling method comprises: a step of detecting a plate end position of the metal plate in a plate width direction; and A step of determining a heating position of the tapered portion in the axial direction based on the detected plate end position.

14. The metal plate rolling method according to claim 11 or 12, wherein: The metal plate rolling method includes the step of changing the heating position by moving a heating unit for heating the tapered portion in the axial direction.

15. The metal plate rolling method according to claim 11 or 12, wherein: The metal plate rolling method comprises: a step of detecting a parameter related to the thickness at the end portions of the metal plate in the plate width direction; and A step of determining the displacement amount of the roller in the axial direction based on the detected parameter.

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