Metal strip and method for passing the strip

Abstract

The purpose of the present invention is to provide a metal strip that makes it possible to reduce sagging at a metal strip leading end and to contribute to improved productivity by only changing the method of threading work, without introducing new equipment, and a threading method for said metal strip.　This metal strip has a width of 850-1270 mm and a thickness of 0.1-0.5 mm, and is characterized by comprising an end part having an isosceles trapezoid shape in which the width is the lower base and the leading end is the upper base, and in that the upper base of the isosceles trapezoid is 200-500 mm and the height of the isosceles trapezoid is 450-600 mm.

Description

Technical Field

[0001] The present invention relates to a method for passing a metal strip, such as a hot-rolled steel strip or a cold-rolled steel strip, through a process line stably, and more particularly to a method for passing a metal strip through a process line by stably passing the leading end of the metal strip unwound from a coil of the metal strip through the process line.

Background Art

[0002] In a process line facility for processing and treating a metal strip to manufacture the metal strip, when paying out a metal strip wound in a coil from a pay-off reel (POR), it is necessary to pass the leading end of the metal strip through the process line facility.

[0003] When the leading end of the metal strip unwound from the coil is passed through the process line facility, if there is a sag in the leading end of the metal strip, the leading end of the metal strip may come into contact with the facility, increasing the risk of the metal strip being bent or the facility being damaged. Here, the sag refers to a state in which the metal strip bends in the width direction, with the central part being high and both ends being low.

[0004] When such an event occurs, it takes time to remove the metal strip and restore the facility, leading to a decrease in productivity. Therefore, methods for eliminating the above-mentioned troubles caused by the occurrence of sag have been proposed. Patent Document 1 discloses a method of adsorbing and holding the leading end of a steel strip by a magnet conveyor and transporting it into a line facility. Further, Patent Document 2 proposes a method of providing a belt drum, connecting a belt to the leading end of a metal strip, and then winding up the belt to perform passing through the plate efficiently with a simple operation. However, these methods are premised on application in a simple passing-through line in a horizontal straight line, and are difficult to apply in a complex line where horizontal and vertical portions are mixed in the passing-through line. In addition, since they also require costs for equipment investment, they are not practical.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-143412 [Patent Document 2] Japanese Patent Application Laid-Open No. 5-42303 [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] Therefore, an object of the present invention is to solve the problems of the prior art as described above. Specifically, without introducing new equipment, only by changing the method of the strip passing operation, it is possible to reduce the sag at the tip of the metal strip and lead to an improvement in productivity, and to provide a metal strip and a method for passing the metal strip. [Means for Solving the Problems]

[0007] The inventors conducted studies to solve the above problems, and as a result, found the following.

[0008] For a metal strip having a width of 850 mm or more and 1270 mm or less and a thickness of 0.1 mm or more and 0.5 mm or less, an isosceles trapezoidal end portion is provided with the tip thereof as an upper base of 200 mm or more and 500 mm or less and the width as a lower base. And it was found that when passing the strip, by supporting and pulling two or more holes (the interval between the holes is 5 mm or more and 180 mm or less) at the end portion with a string-like member, the occurrence of sag is eliminated.

[0009] The present invention is based on the above findings, and the gist thereof is as follows. [1] A metal strip having a width of 850 mm or more and 1270 mm or less and a thickness of 0.1 mm or more and 0.5 mm or less, comprising an isosceles trapezoidal end portion with the width as a lower base and the tip as an upper base, the upper base of the isosceles trapezoid being 200 mm or more and 500 mm or less, and the height of the isosceles trapezoid being 450 mm or more and 600 mm or less. [2] The metal strip according to [1], having a tip reinforcing member 20 mm or more and 50 mm or less in the longitudinal direction from the tip of the metal strip. A method of passing a metal strip as described in [3][1] or [2] through a process line, comprising: drilling holes at two or more positions on the metal strip, starting from the tip of the metal strip, in the longitudinal direction of 5 mm or more and 50 mm or less, symmetric in the width direction, and with an interval between holes of 50 mm or more and 180 mm or less; supporting the metal strip by passing a string-like member through each of the two or more holes; connecting the portion of the string-like member on the side where the metal strip is not supported to the process line; a method of passing a metal strip, wherein the portion of the string-like member is pulled in the conveyance direction of the process line. [4] The method of passing a metal strip according to [3], wherein a metal piece is inserted as a tip reinforcing material from the tip of the metal strip in the longitudinal direction of 20 mm or more and 50 mm or less. [5] The method of passing a metal strip according to [3], wherein when pulling the portion of the string-like member in the conveyance direction of the process line, a plurality of the string-like members are pulled together as one. [6] The method of passing a metal strip according to [4], wherein when pulling the portion of the string-like member in the conveyance direction of the process line, a plurality of the string-like members are pulled together as one. [Effect of the Invention]

[0010] According to the present invention, sagging during passing through the plate does not occur without introducing new equipment, so the passing time through the plate is reduced compared to the conventional method, and the production productivity is improved. Therefore, the industrial utility value is extremely large. [Brief Description of the Drawings]

[0011]

Figure 1

Figure 2

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0013] The present invention is applicable to all conventional batch line facilities for performing processing, treatment, etc. to manufacture metal strips. Here, although the batch line facility is referred to as an example where the application of the present invention is useful, the present invention is not limited to the application to this facility and is applicable to all process lines.

[0014] Hereinafter, embodiments according to the present invention will be described with reference to FIG. 1 as an example.

[0015] In this line, although automatic strip passing is possible from the pay-off reel (POR) to the inlet inspection table at (1) and in the section from the outlet inspection table at (2) to the tension reel (TR), the process line is not straight from the inlet inspection table at (1) to the outlet inspection table at (2). As a result, since the process line has a complex structure, it is necessary to pass the strip manually, and the present invention is particularly useful.

[0016] When starting up the process line immediately after regular maintenance, troubles, etc., it is necessary to first pass a metal strip through the process line. The coil used at this time is called a start-up coil, and first, the start-up coil is loaded into the POR.

[0017] Thereafter, the coil is passed through to the inlet inspection table at (1) in FIG. 1. The passing of the coil up to this point is performed automatically in the same manner as during normal operation. The coil dimensions are applicable to metal strips having a strip width of 850 mm or more and 1270 mm or less and a strip thickness of 0.1 mm or more and 0.5 mm or less.

[0018] An isosceles trapezoid-shaped end portion is formed on the metal strip, where the width of the metal strip is the lower base and the tip of the metal strip is the upper base. This isosceles trapezoid-shaped end portion may be at the end portion on the tip side in the conveying direction of the metal strip. Note that there are no particular restrictions on the components and structure of the metal strip, and it is assumed that those used for ordinary hot-rolled steel strips and cold-rolled steel strips are used.

[0019] At this time, the lower base is the width of the metal strip. The upper base needs to be 200 mm or more and 500 mm or less. If the upper base is less than 200 mm or more than 500 mm, the end of the metal strip will droop during the continuous passing of the sheet, and it will come into contact with the process line. Therefore, the upper base should be 200 mm or more and 500 mm or less. Preferably, it is 300 mm or more and 500 mm or less.

[0020] Also, it is necessary to form the end portion so that the height of the isosceles trapezoid is 450 mm or more and 600 mm or less. If the height is less than 450 mm or more than 600 mm, the balance of the force will be disrupted and the effect of suppressing the drooping cannot be obtained. Therefore, at the end portion of the isosceles trapezoid shape, the height of the isosceles trapezoid should be 450 mm or more and 600 mm or less. The height of the isosceles trapezoid is preferably 500 mm or more and 540 mm or less.

[0021] Here, a known method may be used to form the end portion of the isosceles trapezoid shape on the metal strip. As an example, a method of cutting out the end portion of the isosceles trapezoid shape from a strip-shaped metal strip using, for example, metal shears can be used.

[0022] As shown in FIG. 2, in order to increase the strength during the continuous passing of the sheet, at the inlet inspection table of (1), from the tip of the coiled sheet passed, in the longitudinal direction of the metal strip, a length of 450 mm or more and 600 mm or less corresponding to the height of the end portion of the isosceles trapezoid shape is bent. It is preferable to insert a metal piece bent to a length of about 2 / 3 of the sheet width at this bent portion as a tip reinforcing material. The length of the tip reinforcing material is preferably a length longer than the tip portion after cutting described below, because it leads to an improvement in strength. Also, if the double-fold at the tip is 4 or more, more sufficient strength can be ensured, so it is preferable. Also, the tip reinforcing material is for the purpose of reinforcing the strength of the hole made in the above end portion in order to pass the metal strip later. Therefore, the width of the tip reinforcing material at the time of bending is preferably 20 mm or more and 50 mm or less in the longitudinal direction from the tip of the metal strip. The bent portion is fixed by a known means such as a tape. Also, when using the tip reinforcing material, the end portion of the isosceles trapezoid shape may be cut out after bending the tip of the metal strip and inserting the tip reinforcing material, or the tip reinforcing material may be inserted after cutting out the end portion of the isosceles trapezoid shape.

[0023] Subsequently, holes are drilled at two or more positions on the metal strip such that the length from the tip of the metal strip is 5 mm or more and 50 mm or less in the longitudinal direction, the holes are symmetric in the width direction, and the distance between the holes is 50 mm or more and 180 mm or less. When using a tip reinforcing member, the holes are drilled such that part or all of the holes cover the tip reinforcing member. Here, the distance between the holes means the distance between the centers of the holes. Also, the holes may be of any size as long as a rope can be tied through them, but preferably have a diameter of 15 mm or more and 25 mm or less.

[0024]

[0023] Also, with respect to the width direction of the metal strip, holes are drilled at positions 10 mm or more inside from the width direction ends. Here, the width direction ends refer to the lines drawn perpendicular to the longitudinal direction of the metal strip from both ends of the upper base of the isosceles trapezoid shape as shown in FIG. 2. When the number of holes is odd, after drilling one hole at the center in the width direction, holes are drilled at positions 10 mm or more inside from the ends. When drilling four or more holes in the width direction of the metal strip, the distance between the holes is not particularly limited except that it satisfies the above 50 mm or more and 180 mm or less. For example, the intervals between four or more holes may be equal or may not be equal.

[0025] In this state, after passing the string-like member from the inlet inspection table of (1) to the outlet inspection table of (2), the metal strip is supported by passing the string-like member through two or more holes, and at the outlet inspection table of (2), the part of the string-like member on the side where the metal strip is not supported is pulled to perform through-plating. The part of the string-like member may be pulled manually or using an electric winch or the like. After the through-plating up to the outlet inspection table of (2) is completed, the string-like member is removed, and after cutting the isosceles trapezoid-shaped end (the entire bent part if a bent part is created as the tip reinforcing member at the end), automatic through-plating is performed up to the TR.

[0026] Here, there is no limitation on the string-like member, and it may be any string-like member that can stably support the metal strip. For example, a rope or a sling can be mentioned. Also, there is no limitation on the method of supporting the metal strip through the string-like member. For example, the string-like member may be pulled through each hole, or the string-like member may be tied to each hole and then pulled.

[0027] The string-shaped members may be pulled separately, but it is preferable to pull a plurality of them together because it becomes possible to pass the metal strip more stably. As a method of gathering a plurality of them together, the separate string-shaped members passed through each hole may be tied together with another string-shaped member to form one, or a single string-shaped member may be passed through a plurality of holes, and the loop portion of the string-shaped member may be directly pulled or another string-shaped member may be tied to the loop portion and pulled.

Example

[0028] Regarding the amount of sag (mm) when a cold-rolled steel strip coil having the plate thickness and plate width described in Table 1 was passed through a finishing facility, measurements were taken by changing the upper base and height of the isosceles trapezoid-shaped end, as well as the number of fulcrums during pulling. The results are shown in Table 1. In both the inventive examples and the comparative examples, holes were made at two positions where the length was 40 mm from the tip of the metal strip in the longitudinal direction, symmetric in the width direction, and the interval between the holes was 130 mm. Regarding the method of tying the ropes, the "Y-shaped" means pulling the ropes passed through the holes made at two positions together in a Y-shape. Also, the "single-point support" means pulling by passing a rope through a hole made at one position. The measurement of the amount of sag is first carried out by placing 1 m from the tip of the steel strip on a horizontal table and tying one end of the rope to the hole of the metal strip by the tying method described in Table 1. Then, the end of the steel strip is lifted by gripping the rope not tied to the metal strip, and a ruler, measuring tool, etc. are placed in the vertical direction, and the difference in height from the horizontal table at the central part and both end parts is read. When the amount of sag exceeds 70 mm, the frequency of contact between both sides of the steel strip tip and the roll equipment increases, which hinders the strip passing operation. Therefore, the case where the amount of sag is 70 mm or less is considered qualified.

[0029]

Table 1

Claims

1. A metal strip having a width of 850 mm or more and 1270 mm or less and a thickness of 0.1 mm or more and 0.5 mm or less, comprising an isosceles trapezoidal end portion having the width as the lower base and the tip as the upper base, wherein the upper base of the isosceles trapezoid is 300 mm or more and 500 mm or less, the height of the isosceles trapezoid is 500 mm or more and 600 mm or less, and having holes at two or more positions that are 5 mm or more and 50 mm or less in the longitudinal direction and symmetric in the width direction from the tip of the metal strip, and the interval between the holes is 50 mm or more and 180 mm or less.

2. The metal strip according to claim 1, having a tip reinforcing member 20 mm or more and 50 mm or less in the longitudinal direction from the tip of the metal strip.

3. A method of passing the metal strip according to claim 1 or 2 through a process line, supporting the metal strip by passing a string-like member through the two or more holes, connecting the portion of the string-like member on the side where the metal strip is not supported to the process line, and pulling a plurality of the string-like member portions together in the conveyance direction of the process line. A method of passing a metal strip.

4. The method of passing a metal strip according to claim 3, wherein a metal piece is inserted as a tip reinforcing member 20 mm or more and 50 mm or less in the longitudinal direction from the tip of the metal strip.

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