JP3829858B2 - Metal strip winding device and metal strip manufacturing method - Google Patents

Description

The present invention relates to a metal band winding device such as a cold-rolled steel sheet, and a metal band manufacturing method characterized by winding the metal band by the metal band winding device, and in particular, winding the metal band in a coil shape. When it is taken, it prevents the occurrence of waist folding, which is a quality defect called a top mark (also called an end mark or reel mark), which occurs in the metal band in the inner coil of the second and subsequent coils due to a step due to the thickness of the metal band tip. The present invention relates to a metal band winding device including a mandrel equipped with a metal belt winding rubber sleeve , and a metal band manufacturing method characterized in that the metal band is wound by the metal band winding device.

  A metal strip such as a cold rolled steel sheet is wound into a coil by a winding device after rolling. Thereafter, the coil is unwound for heat treatment or surface treatment, or is wound again in a coil shape by a winding device.

  When a metal strip is wound on a reel, waist folding called a top mark occurs due to a step caused by the thickness of the metal band tip from the beginning of winding of the metal strip to a range of several to several tens of turns.

  FIG. 2 is a cross-sectional view showing a state of a top mark generated when a metal strip is wound on a winding device. The metal band is wound around the outer periphery of the mandrel 3 of the winding device to become a coil 6, but when the metal band becomes the second volume, a top mark 5 is generated due to a step 8 caused by the tip 5 of the metal band, The effect also affects the third and subsequent volumes, and a top mark occurs over several tens of volumes. Since the metal band where the top mark is generated must be scrapped, the yield is greatly reduced.

  Various methods for preventing the occurrence of the top mark have been studied. For example, the following methods are known.

  Patent Document 1 discloses an end mark prevention method that reduces a step by thinly rolling a certain length from the tip of a metal strip to be wound to a plate thickness of 30 to 90% of the product thickness.

  However, in order to reduce the top mark, it is necessary to process the metal strip as thin as possible, but it is difficult to process it into a complete taper by processing by rolling. Even when processing a sharp metal band tip by grinding or the like, there is a risk of piercing the belt wrapper used when winding the metal band or the rubber sleeve attached to the winding device and damaging them. .

  Patent Document 2 discloses a method in which the tip of the metal band is processed into a taper shape with a cutter to reduce the level difference at the tip of the metal band.

  However, the method of reducing the level difference due to the metal band tip by processing the metal band tip thinly in a taper shape is unstable and difficult to machine accurately in the width direction.

  In Patent Document 3, Patent Document 4 and Patent Document 5, a technique for reducing the level difference at the metal band tip by inserting a cushioning material such as felt or a corrugated cardboard foamed polystyrene plate into a portion where the tip of the metal band overlaps the second roll. Is disclosed.

  However, the above-described technique using the buffer material to reduce the step at the metal band tip requires complicated control because the buffer material needs to be attached to a predetermined position of the metal band. For this reason, there is a case where it is simply attached manually, but the time loss is large, which is a problem in terms of safety.

  Patent Document 6 and Patent Document 7 disclose a technique using a rubber sleeve in which a soft rubber is embedded in a dent or a dent at a position where the tip of the steel strip hits.

  The technique of using a rubber sleeve with a dent or soft part at the position where the tip of the steel plate hits is to wind the metal band at a predetermined position with a dent or soft part when winding the metal band around the winding device for the first time. It is necessary to take. Therefore, complicated control is required, but accurate control is difficult. Further, since the shape of the recess is constant, it cannot be handled when the plate thickness of the metal strip to be wound is greatly changed. If the dent is deepened in accordance with the maximum plate thickness, it is possible to prevent the top mark from being generated at the tip of the metal band, but a waist break occurs at the end of the dent. It is necessary to have several types of rubber sleeves according to the plate thickness, and if the plate thickness changes, the rubber sleeve must be replaced, which significantly impairs productivity.

  In Patent Document 8, a part of the elastic sleeve fitted to the mandrel of the winding device is provided with a cavity that extends in the longitudinal direction of the sleeve and has a width in the circumferential direction, and the internal pressure can be adjusted. A method is disclosed in which the tip of the metal strip is wound so as to coincide with the outer peripheral position of the cavity.

  However, in this method, it is necessary to adjust the internal pressure of the cavity portion depending on the thickness of the metal strip to be wound, which requires a cavity internal pressure adjusting device and increases the equipment cost.

As described above, various measures for preventing the top mark have been studied, but the present situation is that the generation of the top mark has not been completely prevented yet, such as an increase in equipment costs.
Japanese Examined Patent Publication No. 61-126927 JP-A 63-237858 JP 59-1019 A JP-A-5-337542 Japanese Utility Model Publication No. 52-1000083 JP-A-6-16341 JP-A-6-246349 Japanese Patent Laid-Open No. 7-80543

An object of the present invention is to solve various problems in the conventionally proposed methods for preventing top marks, to suppress the generation of top marks without requiring special equipment, and It is an object of the present invention to provide a metal band winding device including a mandrel equipped with a rubber sleeve that can cope with any plate thickness, and a metal band manufacturing method using the metal band winding device.

  The present inventor provides a gap in the rubber sleeve, and the metal band tip is brought into contact with the sleeve outer surface of the gap and wound up, thereby pushing the metal band tip into the gap and preventing the top mark. As a result of various experiments and examinations on the method, the following findings were obtained.

  1) The size of the generated top mark varies depending on the shape of the gap provided in the outer surface layer portion of the rubber sleeve.

  2) The formation of the top mark can be prevented by making the shape of the gap portion the largest in the cross section in the direction perpendicular to the central axis of the sleeve and becoming smaller toward both ends.

  3) In order to cope with winding of metal strips having different plate thicknesses with a single rubber sleeve, a spacer may be inserted into the gap to adjust the size of the gap.

The present invention has been made based on such findings, and the gist thereof is as shown in the following (1) and (2) .
( 1 ) A metal strip winding device provided with a mandrel equipped with a cylindrical rubber sleeve, the rubber sleeve having a width parallel to the central axis of the sleeve and circumferentially in the outer surface layer portion of the sleeve A gap portion and a spacer that is inserted into the gap portion to adjust the size of the gap are provided, and the gap gap in the cross section perpendicular to the central axis of the sleeve is the largest at the center portion and becomes smaller toward both ends. a metal strip winding device, characterized in that are.
( 2 ) A method for producing a metal strip, wherein the metal strip is wound up by the metal strip winding device according to (1) .

Hereinafter, the rubber sleeve used by this invention is demonstrated using drawing.
FIG. 1 is a view showing an example of a rubber sleeve used in the present invention, where (a) is a side view and (b) is a front view. Since the size of the gap 2 can be adjusted by inserting a spacer in the gap, if the spacer is inserted into the gap when winding a metal strip having a different thickness, Can be handled with one rubber sleeve.

  Here, the sleeve radial direction is the Y direction which is the diameter direction of the sleeve 1 shown in FIG. 1B, and the circumferential direction is the X direction of FIG.

  The inventor conducted various studies on the shape of the gap using a steel plate. First, the winding analysis by finite element method (FEM) was performed.

  FIG. 10 is a diagram showing a winding analysis model by a finite element method. As shown in the figure, the steel strip 10 is wound on the steel strip tip 5 and the surface pressure generated by the subsequent winding is applied to the surface of the steel plate.

  The analysis conditions are as shown in Table 1, and the shape of the void was variously changed. The preferable shape and the unfavorable shape will be described.

  FIG. 3 is a diagram showing the analysis results, in which FIG. 3 (a) shows a case of winding with a normal rubber sleeve, FIG. 3 (b) shows a case of winding with a rubber sleeve having a rectangular gap in cross section, The figure (c1) shows the case where it winds up with the rubber sleeve which provided the hollow on the sleeve surface, and the figure (d1) shows the case where it winds up with the rubber sleeve of this invention. Each figure shows the state after deformation after winding, and the blacked portion shows the plastically deformed element.

  3 (b2), (c2), and (d2) are cross-sectional views around the voids and depressions provided in the rubber sleeve, and the dimensions are as follows.

FIG. 3 (b2)
w2: 50 mm, h2: 2 mm, t2: 8 mm
FIG. 3 (c2)
w3: 50 mm, r3: 130 mm,
FIG. 3 (d2)
w1: 70mm, h2: 4mm, t2: 8mm
In the case of FIG. 3 (a1), the steel plate is plastically deformed at the tip position of the steel plate, and a top mark is generated.

  In the case of FIG. 3 (b1), it is shown that the steel plate is plastically deformed and top marks are generated at both end positions of the gap and at the front end position of the steel plate.

  In the case of FIG. 3 (c1), the top mark is not generated at the front end position of the steel plate, but the steel plate is plastically deformed at the both end positions of the recessed portion, and the top mark is generated.

  On the other hand, in the case of the rubber sleeve of the present invention shown in FIG. 3 (d1), the steel plate is not plastically deformed at both the end portions of the gap and the front end position of the steel plate, and no top mark is observed.

  FEM analysis was performed for variously shaped voids, but the shape of the void as shown in FIG. 3 (d2) is the largest at the center, and the smaller shape toward both ends has the effect of preventing top marks. It was confirmed.

According to the rubber sleeve used in the present invention , generation of top marks can be almost suppressed, product defects caused by winding are reduced, and product quality and metal band yield are remarkably improved. In addition, even if the thickness of the metal strip to be wound is changed, there is an advantage that the rubber sleeve can be wound without being replaced by appropriately inserting a spacer.

Hereinafter, embodiments of the present invention will be described in detail.
Although the material of the cylindrical rubber | gum three rubber | gum used by this invention is not limited, The oil-resistant rubber | gum (NBR) normally used may be sufficient. If the hardness of the rubber is too hard, the effect of preventing the generation of the top mark is small, and it is preferably Hs 80 or less. Hs60-70.

  The reason why the thickness of the gap in the cross section in the direction perpendicular to the central axis of the sleeve, that is, in the X direction in FIG. 1 is defined as being thickest at the center and thinner toward both ends is as follows. Street.

FIG. 4 is a view showing a cross-sectional shape of the gap in the cross section in the X direction of FIG. 1 (a) and showing a typical gap provided in the rubber sleeve used in the present invention.

  4A shows a void whose top surface is flat and the bottom surface is inclined from the center toward both ends, and FIG. 4B is a void whose bottom surface is flat and the top surface is curved. (C) is an air gap whose upper surface is a curved surface and whose lower surface is inclined from the center to both ends, and FIG. The air gap which inclines as it goes to both ends, FIG. 5E is a diagram showing the air gap upper surface with a curved surface, and the lower surface with the flat portion L2 and the air gap which inclines from both ends toward both ends of the air gap. The hatched portion in the figure indicates the cross-sectional shape of the spacer 9.

  As shown in these drawings, the gap is smaller from the center C toward both ends E1 and E2, and the gap is smaller and is the largest at the center C as indicated by h. This shape is achieved by suppressing the generation of top marks by winding the tip end portion of the metal band in contact with the outer surface of the rubber sleeve near the center of the gap, and the metal at both ends E1 and E2 of the gap. This is to prevent the belt from folding back.

  As shown in FIG. 3 (b2), if the gap h is the same at the center and at the end, hip breakage occurs at both ends of the gap.

FIG. 6 is a cross-sectional view in the sleeve radial direction of the gap provided in the rubber sleeve.
FIG. 7 is a view for explaining the state of occurrence of the top mark, and FIG. 7A shows the case of the rubber sleeve provided with the gap shown in FIG. 4C of the present invention. b) and (c) show the case of a rubber sleeve having a rectangular cross section.

  In the case of FIG. 7A, the gap 2 in the outer surface layer of the rubber sleeve 1 is the largest at the center and becomes smaller toward both ends, so the rubber at the tip of the metal band sinks into the gap. No top mark is generated on the second metal strip 9 on the top of the strip. Further, since the gap becomes smaller as it goes toward the end of the gap, the waist break does not occur at the end of the gap.

  On the other hand, in the case of FIG. 7B, the rubber between the gap and the sleeve surface is thick, and the gap in the gap cross section is a constant rectangular cross section. A top mark 7 is generated by the step of the tip 5.

  Further, even if the space between the outer surface of the rubber sleeve and the gap is reduced as shown in FIG. 3C so that the rubber sinks into the gap, a top mark is generated at the gap end portion E.

  The reason why the gap is maximized in the central portion of the gap is to allow the rubber sleeve to be used without replacing the winding direction when the metal strip is wound.

  FIG. 5 is a cross-sectional view showing the state of the metal band at the beginning of winding in the gap. FIG. 5A shows the case of winding in the right direction (A direction in the figure), and FIG. Shows the case of winding. As shown in the figure, when the metal band tip 5 is positioned and wound at a position corresponding to the center C having the largest gap 2, it is wound in both directions only by changing the rotation direction of the rubber sleeve 1. Is possible.

  The size of the gap is not limited because it varies depending on the thickness of the metal strip to be wound, the material, the hardness of the rubber sleeve rubber, the outer diameter of the mandrel, and the like.

  The thickness range of normal cold-rolled steel strip (carbon steel plate, stainless steel plate) is about 0.5 to 3.2 mm, and rubber sleeves with diameters of about 508 and 610 mm are generally used.

  The size positions of the voids suitable for attaching a rubber sleeve having a diameter of 508, 610 and a hardness of Hs 50 to 70 to the mandrel and winding the steel strip having the above thickness are as follows.

8mm <H <20mm
t × 1.05 <h <t × 2.0
Note that the size of the gap is set so that the maximum thickness of the metal strip to be wound can be wound, and when the plate thickness to be wound is thin, a metal strip of various thicknesses can be formed by inserting a spacer in the gap. Can be rolled up. The shape of the spacer 9 can be a shape as shown in 9a to 9d in FIG.

  Further, when winding, the tip of the metal strip does not necessarily have to come to the outer surface of the rubber sleeve corresponding to the center of the gap. In other words, if the gap at the center of the gap is made larger than the plate thickness, winding can be performed without generating a top mark even if the tip of the metal band is slightly shifted back and forth from the center of the gap. In particular, as shown in FIGS. 4D and 4E, if the large gaps L1 and L2 are provided in the central part of the gap, the allowable deviation range of the metal band tip increases.

  The effects of the present invention will be described below with reference to examples.

As the rubber sleeve used in the present invention , a rubber sleeve having a hardness Hs65 provided with a gap having the shape shown in FIG. 3D and a rubber sleeve having a hardness Hs65 provided with a gap having a rectangular cross section were prepared as a comparative example. In both cases, the outer diameter was 508 mm, the sleeve thickness was 51 mm, and the sleeve width was 1200 mm.

  FIG. 8 is a cross-sectional view showing the shape and position of the gap provided in the rubber sleeve used in the present invention. FIG. 8 (a) shows an example of the present invention, and FIG. 8 (b) shows a comparative example. The dimensions were as follows.

<Invention Example><ComparativeExample>
H1: 8mm H2: 6.4mm
h1: 3mm h2: 1.6mm
W1: 50mm W2: 50.8mm
These rubber sleeves are mounted on a mandrel of a winding device, and a cold rolled steel strip (yield point 28 kgf / mm ² ) of low carbon steel having a plate thickness of 2.5 mm and a plate width of 1000 mm is used and wound up under the following conditions: It was.

Winding tension: 3 kgf / mm ²
Total winding number: 300 windings The wound coil was unwound with no tension, and a sample for measuring the top mark was taken from the 2nd to 50th steel strip located at the tip of the steel strip.

  FIG. 11 is a diagram for explaining a top mark evaluation method.

  As a top mark evaluation method, the contact displacement meter 11 is attached to the rotating shaft 12 and the rotating shaft 12 is rotated by the motor 13 to move the contact displacement meter 11 in the sample winding direction and measure the plate shape. The curvature was obtained by inputting to a personal computer and taking the second derivative.

  FIG. 12 is a diagram showing a change state of the obtained shape and curvature of the steel sheet. As shown in the figure, the difference between the maximum value of the curvature of the top mark portion and the curvature of the base material (winding and warping) was defined as the top mark curvature, and the top mark was evaluated.

FIG. 9 is a diagram showing a top mark measurement result. As is apparent from the figure, when the rubber sleeve used in the present invention is wound, the top mark is almost disappeared after the fourth roll. In contrast, in the case of using a rubber sleeve according to the comparative example, the top mark enough also a problem in 20 tum has occurred.

In addition, four types of rubber sleeves having the same gap as the rubber sleeve used in the present invention and having a rubber hardness of Hs45, 65, 80 and 90 are manufactured, and the plate thickness is as low as 1.6 mm and 2.3 m. The carbon steel strip was wound up under the same conditions as described above, a sample was taken from the portion corresponding to the tip of the fifth steel strip of each coil, and the top mark was evaluated by the same method as described above. The results are shown in Table 2.

As apparent from the table, the hardness is Hs80 or less and the top mark is small. However, even if the hardness is Hs90, it can be seen that the size of the top mark is smaller in the rubber sleeve used in the present invention than in the comparative example shown in FIG.

According to the metal strip winding device including the mandrel equipped with the rubber sleeve used in the present invention and the metal strip manufacturing method using the metal strip winding device, the generation of the top mark can be almost suppressed. Can reduce product defects and significantly improve product quality and metal strip yield. Further, even if the thickness of the metal strip to be wound changes, it can be wound without replacing the rubber sleeve by appropriately inserting a spacer .

It is a figure which shows an example of the rubber sleeve used by this invention, (a) is a side view, (b) is a front view. It is explanatory drawing of the top mark which generate | occur | produces at the time of winding of a metal strip. It is a figure which shows the analysis result of the stress produced in the front-end | tip part vicinity, when winding a metal strip. Ru Oh a diagram showing the void shape in the cross section in a direction perpendicular to the radial direction of the rubber sleeve. It is sectional drawing which shows the state of the metal band tip of the winding start in a space | gap part. It is sectional drawing of the sleeve radial direction of the space | gap part provided in the rubber sleeve. It is a figure for demonstrating the generation | occurrence | production situation of a top mark. It is sectional drawing which shows the shape and position of the space | gap provided in the rubber sleeve, It is a figure which shows the generation | occurrence | production situation of the top mark of the wound steel strip. It is a model figure used for FEM winding analysis. It is a figure for demonstrating the shape measuring method of the top mark sample of a steel strip. It is a figure which shows the change state of the shape and curvature of a steel plate.

Explanation of symbols

1 Rubber sleeve 2 Air gap 3 Mandrel 4 Metal band 7 Top mark 9 Spacer

Claims (2)

A metal band winding device provided with a mandrel equipped with a cylindrical rubber sleeve, the rubber sleeve having a gap portion parallel to the central axis of the sleeve and having a width in the circumferential direction in the outer surface layer portion of the sleeve And a spacer that is inserted into the gap and adjusts the size of the gap, and the gap gap in the cross section in the direction perpendicular to the central axis of the sleeve is the largest at the center and decreases toward both ends. A metal band winding device characterized by the above. A metal band is wound up by the metal band winding device according to claim 1 .

Images