JP3838497B2 - Metal strip unwinding device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The invention according to the claim makes the surface wrinkles caused by the folding phenomenon of the metal band as small as possible or made inconspicuous when unwinding the metal band wound in a coil shape (strip-shaped thin metal plate) from the uncoiler. Therefore, the present invention relates to an unwinding method and unwinding device for a metal strip.
[0002]
[Prior art]
In order to perform any treatment such as plating, pickling, rolling, annealing or cutting on a thin metal plate, a process of unwinding (unwinding) a long metal strip wound around a coil is often required. . The unwinding of the metal strip from the coil is carried out by holding the coil on an uncoiler, peeling off the metal strip in order from the end on the outer periphery, and feeding it between adjacent rolls of pinch rolls.
[0003]
When a metal strip wound around a coil is unwound, a so-called “lumbar break” phenomenon tends to occur. As a result of unwinding, bending stress concentrates locally and in a wavy manner on the surface of the metal band, and as a result, a large number of wrinkles extending in the width direction are generated on the surface of the metal band at intervals of several mm.
[0004]
As a conventional device for preventing such a hip folding phenomenon, a device shown in FIG. 4 is known (Japanese Patent Laid-Open No. 9-70618). In the illustrated apparatus, a steel strip Y is unwound from a coil X held by an uncoiler 31 toward a pinch roll 32, and the steel strip Y is applied to a leveler 33 and then cut by a shear 34. Reference numeral 31a in the figure is a coil carriage having a lifting function. If it is determined that hip breakage is likely to occur, supply cooling water to coil X to keep the temperature of steel strip Y below a certain value, or increase the unwinding (threading) speed to keep the strain rate constant. By setting it above the value, hip breakage is prevented. The steel strip Y to be unwound is pressed against the steel strip Y by pressing a pressure roll 31b from the outside of the coil X as shown in the figure, The strain rate is determined in relation to the outer diameter of the roll 31b.
[0005]
[Problems to be solved by the invention]
In order to prevent the steel strip from being folded with the device as shown in Fig. 4, it is actually implemented because of the considerable cost of coil cooling equipment and the need to rapidly increase the threading speed when necessary. There are some aspects that are not easy. Further, in order to increase the strain rate and prevent hip breakage, it is preferable to make the pressure roll thin (that is, to have a small diameter), but if it is too thin, the roll may bend due to the tension of the steel strip.
[0006]
On the other hand, according to the investigations by the inventors, the strength of the metal band can be reduced if the pitch (interval) of the wrinkles caused by the hip fold can be reduced (less than about 1 mm) even when the hip fold cannot be completely prevented.・ No substantial inconvenience occurs in appearance. Moreover, in order to reduce the wrinkle pitch in this way, it has been found that it is important for the pressure roll to have a wider winding angle of the metal band on its surface than the diameter.
[0007]
SUMMARY OF THE INVENTION The present invention is intended to provide a simple unwinding method and unwinding device that can eliminate the substantial influence of hip folding by reducing the pitch of wrinkles.
[0008]
[Means for Solving the Problems]
The unwinding device for a metal band according to claim 1 is for unwinding a metal band wound as a coil from an uncoiler to an adjacent upper pinch roll (or means for sandwiching a metal band in the same manner as a pinch roll). A pressure roll is arranged between the uncoiler and the pinch roll so as to be pressed against the metal strip to be unwound from the outside of the coil,
a) The pressure roll is in contact with the peripheral surface of the backup roll supported at both ends by a backup roll supported at the tip of the swing arm and a bracket that is rotatably displaceable around the support shaft of the backup roll. is constituted by the work rolls to Rutotomoni,
b) A backup roll of the pressure roll is connected via a link to the operation part at the lower end of the linear operation means fixedly arranged vertically downward as an output source for pressing against the metal strip,
c) The backup roll of the pressure roll is pushed down by the linear motion means as the coil diameter decreases, and the link changes the inclination between the pinch roll and the uncoiler by the action of the swing arm,
d) The work roll of the pressure roll always moves while maintaining the position where the metal band is wound around the angular range of 90 ° or more (less than 180 °) on the peripheral surface regardless of the coil diameter. And
The above (and referred to below) angular range for causing wind around the metal strip on the peripheral surface of the work rolls of the pressure roll, means a wrap angle θ shown in FIG. 2 or FIG. 3, the pressure roll (in particular workpiece If the angle formed by the metal band before and after ( roll) is α,
θ = 180 ° -α
It is. As the linear operation means, a mechanism including a screw (or ball screw) or a rack and pinion may be used together with a motor or the like in addition to the fluid pressure cylinder.
[0009]
When a metal strip is wound around such a wide angle range on the surface of the work roll of the pressure roll, the wrinkles generated on the surface of the metal strip due to folding back can be reduced (at most, about 1 mm or less). Various disadvantages including the elimination of substantial disadvantages in the production of metal strips. When wound in a wide angle range, the metal strip is bent in the opposite direction (longer in terms of time and distance) while being wound on the coil while being fed on the work roll circumference. Therefore, it is considered that the wrinkle interval is narrowed. According to the investigation by the inventors, a preferable effect can be obtained if the angle range is 90 ° or more, but it is most preferable that the angle range is about 120 ° or more.
[0010]
When the metal strip is unwound from the coil, the coil diameter gradually decreases, and the positional relationship between the surface of the coil and the pressure roll (the backup roll and the work roll) changes. However, regardless of such changes, if the metal band is always wound around the angular range of 90 ° or more of the work roll peripheral surface as described above, the entire length of the metal band unwound from the coil is as described above. Wrinkle spacing can be reduced.
In this device, the position of the pressure roll (the backup roll and work roll) can be appropriately changed by the swing arm, and the necessary pressing force can be smoothly applied to the pressure roll (same as above) to be pressed against the metal band. Can do. This is because, firstly, since the linear motion means transmits the output to the tip of the swing arm, not near the base of the swing arm, a large pressing force can be efficiently applied to the metal strip. Secondly, since the operating portion of the linear motion means and the tip of the swing arm are connected via the link as described above, the linear motion means need not be arranged so as to be angularly displaceable. This is because it is sufficient to arrange the linear motion means in a fixed manner with respect to a specific frame (thus, various linear motion means can be used in the most stable manner).
[0013]
In the metal strip unwinding device according to claim 2, the pressure roll (the backup roll and the work roll) is moved from a position near the pinch roll by changing the inclination of the link as the coil diameter decreases. It moves to the position near the uncoiler.
[0014]
According to this apparatus, the pressure roll (especially the work roll) is always pressed against the outside of the coil regardless of the coil diameter, and the metal band is wound around an angular range of 90 ° or more (less than 180 °) on the peripheral surface. It will move while keeping the position to hide.
[0015]
The unwinding device according to claim 3 is characterized in that, in particular, the diameter of the work roll in the pressure roll is set to 200 mm or less.
[0016]
Among the pressure rolls, even if the work roll , which is a roll that is directly pressed against the metal strip, has a small diameter of 200 mm or less , the deflection is prevented by the action of the contacting backup roll even if the rigidity is lowered . If the work roll has a small diameter, it is possible to appropriately control the strain rate and the like of the metal band to prevent the metal band from folding or to make the degree of hip folding gentle.
[0017]
If a small-diameter work roll that changes its position while maintaining contact with the peripheral surface of the backup roll is used, it is easy to wrap the metal strip in a wide angular range on the peripheral surface according to claims 1 and 2. . This is because, as illustrated in FIG. 2 or FIG. 3, the thin work roll enters the narrow space between the coil and the pinch roll, which is difficult to be positioned with a thick roll. In addition, due to such an action, this unwinding device can unwind the metal strip from the coil appropriately and smoothly even when the uncoiler and the pinch roll are arranged close to each other due to the layout, etc. Can eliminate (or reduce) the effects of hip breaks.
[0019]
If the work roll is thin like this, the metal band can be prevented from being folded back or gently as described above, and it is easy to wrap the metal band around a wide angle range on the peripheral surface. It is possible to effectively eliminate the inconvenience of wrinkles on the belt surface. However, if the work roll has a too small diameter, the dimension protruding from the peripheral surface of the backup roll becomes too small, and the degree of the work roll entering the space between the coil and the pinch roll becomes small as described above. Therefore, the diameter is desirably 50 mm or more and 200 mm or less.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the invention is shown in FIGS. FIG. 1 is an overall side view showing a steel strip Y unwinding device 10 together with the devices from the decoiler 1 to the leveler 4. 2 and 3 are side views showing the unwinding state of the steel strip Y performed using the unwinding device 10. FIG. 2 shows a case where the diameter of the coil X is large, and FIG. Each time is small.
[0021]
Each apparatus shown in FIG. 1 is disposed on the upstream side in a shear line of a hot-rolled steel sheet, and relates to a process of unwinding and flattening a steel strip Y manufactured by hot rolling from a coil X. The uncoiler (mandrel) 1 on the right side in the figure holds the coil X of the steel strip Y and rotates leftward in the figure, thereby unwinding the steel strip Y from the outside to a slightly upper adjacent position (left side in the figure). A certain pinch roll 2 is fed between a pair of rolls 2a and 2b. The steel strip Y passing through the pinch roll 2 is further guided by a guide 3 (including a lower guide 3a and an upper guide 3b as shown in FIG. 2) and passed between the rolls of the leveler 4 and flattened by lightly reducing it. To do. In the leveler 4, a plurality of work rolls 4 a supported by the backup roll 4 b are arranged on the lower side, while a plurality of work rolls 4 c supported by the backup roll 4 d connected to the reduction hydraulic cylinder 4 e are arranged on the upper side. And the lower work roll 4a and the like. The pinch roll 2 sandwiches the steel strip Y by pressing the upper roll 2b against the lower roll 2a with a hydraulic cylinder (crushing means) 2c, thereby determining the position of the steel strip Y, and The tension can be applied to the steel strip Y before and after that.
[0022]
An unwinding device 10 is arranged between the uncoiler 1 and the pinch roll 2 as shown in FIG. The unwinding device 10 presses the pressure roll 20 against the steel strip Y from the outside of the coil X as shown in FIGS. 2 and 3, and causes the steel strip to bend in the direction opposite to that when it is wound around the coil X. It is for adding to Y. The role of the unwinding device 10 is to make the wrinkles on the surface of the steel strip Y caused by the so-called hip-folding phenomenon inconspicuous with a small pitch by appropriately performing the pressing.
[0023]
The unwinding device 10 is configured as described in a) to d) below.
a) A pressure roll 20 to be pressed against the steel strip Y is provided at the tip of the swing arm 11. The swing arm 11 is an arm (consisting of a pair of parallel members) that is swingable within a vertical plane with the swing center 11a positioned slightly above the pinch roll 2 across the center of the uncoiler 1. is there. If the pressure roll 20 is provided at the tip of the swing arm 11, it is easy to move the pressure roll 20 to an appropriate position in accordance with the change in the diameter of the coil X accompanying unwinding.
[0024]
b) The pressure roll 20 includes a backup roll 21 attached to the tip of the swing arm 11 and a work roll 22 supported by the backup roll 21. The work roll 22 is a roll that is actually pressed and brought into contact with the surface of the steel strip Y as shown in FIGS. By providing a bracket 22a that is freely rotatable about the support shaft 21a of the backup roll 21 and supporting both ends of the work roll 22 with the bracket 22a, the work roll 22 always keeps contact with the peripheral surface of the backup roll 21. While being displaced. Although the diameter of the backup roll 21 is about 300 mm, the work roll 22 is made thin with a diameter of about 150 mm so that the effect of preventing hip breakage can be enhanced.
[0025]
c) The hydraulic cylinder 13 is fixedly disposed as a source of force for pressing the pressure roll 20 against the steel strip Y, and the tip of the swing arm 11 is connected to the operating portion thereof. That is, the hydraulic cylinder 13 which is a linear operation means is fixed vertically downward on the fixed frame 12, and the operation portion at the lower end thereof is arranged as a chock 14 that can move up and down within the guide frame 16 integrated with the fixed frame 12, A fulcrum 15 provided in the chock 14 and a support shaft 21 a of the backup roll 21 are connected by a link 17. Such a mode of arrangement and connection is advantageous in that a downward force can be exerted strongly and efficiently on the pressure roll 20, and the arrangement of the hydraulic cylinder 13 (linear movement means) is simplified. There is. When the steel strip Y is low carbon steel having a thickness of 4.5 mm and a width of 1200 mm, the hydraulic cylinder 13 exerts a pressing force of about 5 to 10 tons.
[0026]
d) The position of the pressure roll 20 determined by the length and angle of the oscillating arm 11 and the position of the oscillating center 11a is the steel strip Y at a location near the pinch roll 2 as shown in FIGS. It is stipulated to be pressed against That is, the pressure roll 20 is always positioned near the inclined surface of the coil X between the pin of the uncoiler 1 and the pinch roll 2, not at the uppermost part of the coil X or at a position farther from the pinch roll 2. I have to. By doing so, among the pressure rolls 20, the work roll 22 is brought into contact with the steel strip Y in a wide angular range on its peripheral surface as shown in FIGS. 2 and 3, and the winding angle range θ becomes 120 ° or more. I did it. In the embodiment, when the outer diameter of the coil X is large at the initial stage of unwinding of the steel strip Y as shown in FIG. 2, the winding angle range θ is about 120 °, and unwinding as shown in FIG. When the outer diameter of the coil X is small in the latter period, the winding angle range θ is around 140 °. When the steel strip Y is wound around such a wide angle range on the work roll 22, the wrinkles generated on the surface of the steel strip Y by folding the waist can be narrowed (on average, about 0.3 mm), and the strength and appearance can be reduced. There are no inconveniences in various points. Note that the work roll 22 that freely rotates and displaces together with the bracket 22a while maintaining contact with the backup roll 21 balances the tension of the steel strip Y before and after being wound around it, so that no special control is required. The steel strip Y is constantly wound around the coil X at a position close to the outer periphery. And it means that the work roll 22 properly enters the narrow space between the coil X and the pinch roll 2 both in the initial stage (FIG. 2) and later (FIG. 3) of unwinding the steel strip Y. The contact in the wide angle range mentioned above with respect to the steel strip Y is facilitated.
[0027]
According to the unwinding apparatus 10 demonstrated above, unwinding of the steel strip Y from the coil X to each apparatus after the pinch roll 2 can be performed as follows.
{Circle around (1)} As shown in FIG. 1, the hydraulic cylinder 13 of the unwinding device 10 is contracted to raise the pressure roll 20 and the swing arm 11 together with the chock 14, and the coil X is set in the uncoiler 1 in this state. After that, the end of the steel strip Y is pulled out from the outer periphery of the coil X, and sent out to the pinch rolls 2 and subsequent.
[0028]
(2) After pinching the steel strip Y with the pinch roll 2, the hydraulic cylinder 13 of the unwinding device 10 is extended as shown in FIG. 2, and the pressure roll 20 is pushed down together with the chock 14 and the swing arm 11. The work roll 22 of the pressure roll 20 is bent by winding the steel strip Y around a wide angular range (θ≈120 °) on its outer periphery as shown in the figure, and applying a downward tension. As a result, the steel strip Y unwound from the coil X is less likely to be bent, and even if it occurs, the surface wrinkles are not noticeable.
[0029]
(3) As the steel strip Y unwinds, the diameter of the coil X decreases as shown in FIG. 3, but the work is always performed by increasing the amount of extension of the hydraulic cylinder 13 and pushing down the pressure roll 20 accordingly. The steel strip Y is continuously wound around a wide angular range (θ ≧ 120 °) on the outer periphery of the roll 22. By doing so, the wrinkles on the surface of the entire length of the steel strip Y can be made inconspicuous.
[0030]
In addition, although unwinding of the steel strip Y in the shear line of a hot-rolled steel sheet was introduced here, the method and apparatus of the invention are not limited to these examples. That is, it is effective in unwinding the metal strip from the coil for various processes such as plating, pickling, rolling (including skin pass) and annealing in addition to shear line.
[0031]
【The invention's effect】
According to the metal band unwinding device of the first aspect, it is possible to reduce the interval between the wrinkles generated on the surface of the metal band due to the folding of the waist, and it is possible to eliminate the substantial inconvenience in the metal band manufacturing. In spite of the coil diameter changing as the metal strip is unwound from the coil, it is possible to obtain the above-described advantages over the entire length of the metal strip. It is also easy to appropriately change the position of the pressure roll (the backup roll and the work roll) according to the change in the coil diameter.
[0032]
Further, according to this apparatus, the position of the pressure roll (the backup roll and the work roll) can be appropriately changed by the swing arm, and the necessary pressing force can be smoothly applied to the pressure roll (same as above). . There is also an advantage that various linear motion means can be used in the most stable manner.
[0033]
In the metal band unwinding device according to claim 2, the pressure roll (especially the work roll) is always pressed against the outside of the coil regardless of the coil diameter, and is 90 ° or more (less than 180 °) on the circumferential surface. It can move while keeping the position where the metal band is wound around the angle range.
[0034]
In the apparatus according to claim 3, in order to further reduce the diameter of the work roll that is directly pressed against the metal band among the pressure rolls, the metal band is prevented from breaking or the degree of hip folding is gentle, or the waist is broken. Even when this occurs, it is easy to reduce the influence on the surface properties of the metal strip .
[Brief description of the drawings]
FIG. 1 is an overall side view showing a steel strip Y unwinding device 10 together with devices from an uncoiler 1 to a leveler 4 as an embodiment of the invention.
2 is a side view showing an unwinding situation of a steel strip Y performed using the unwinding device 10 of FIG. 1, and shows a situation when the diameter of a coil X is large. FIG.
3 is a side view showing an unwinding situation of a steel strip Y performed using the unwinding device 10 of FIG. 1, and shows a situation when the diameter of a coil X is small.
FIG. 4 is a schematic side view showing a conventional device for preventing the steel strip Y from being folded back.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Uncoiler 2 Pinch roll 10 Unwinding device 11 Swing arm 13 Hydraulic cylinder (linear movement means)
17 Link 20 Pressure roll 21 Backup roll 22 Work roll X Coil Y Steel strip (metal strip)

Claims (3)

A device for unwinding a metal band wound as a coil from an uncoiler toward an adjacent upper pinch roll,
A pressure roll is arranged between the uncoiler and the pinch roll so as to be pressed from the outside of the coil to the metal strip to be unwound,
a) The pressure roll is in contact with the peripheral surface of the backup roll supported at both ends by a backup roll supported at the tip of the swing arm and a bracket that is rotatably displaceable around the support shaft of the backup roll. is constituted by the work rolls to Rutotomoni,
b) A backup roll of the pressure roll is connected via a link to the operation part at the lower end of the linear operation means fixedly arranged vertically downward as an output source for pressing against the metal strip,
c) The pressure roll backup roll is pushed down by the linear movement means as the coil diameter decreases, and the link changes the inclination between the pinch roll and the uncoiler by the action of the swing arm,
d) Metal band unwinding device, characterized in that the work roll of the pressure roll always moves while maintaining the position where the metal band is wound in an angular range of 90 ° or more on the peripheral surface regardless of the coil diameter. .   2. The metal strip unwinding device according to claim 1, wherein the pressure roll moves from a position near a pinch roll to a position near an uncoiler by changing the inclination of the link as the coil diameter decreases. The metal strip unwinding device according to claim 1 or 2 , wherein the diameter of the work roll in the pressure roll is 200 mm or less.

Images