JP4016818B2 - Manufacturing method of H-shaped steel with flange tip R and its hot rolling device row - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing an H-shaped steel with a flange tip R in which R (roundness) is imparted to a corner portion of the flange, and a hot rolling device array thereof.
[0002]
[Prior art]
H-shaped steel is used for general building structures, but depending on the application, it may be painted for the purpose of rust prevention. The flange shape of the H-shaped steel has a right angle, but when painted, it is desirable that R (roundness) be formed at the corner of the tip in order to improve paint adhesion and prevent peeling. Here, R must be formed on the inner side and the outer side of the flange tip, respectively, and the radius of the arc is not only the same, but also different radii R1, R2.
[0003]
Shaped steel having a flange, such as H-shaped steel, is generally produced in a rolling line having a breakdown mill, a universal mill and an edger mill. The material steel slab that has come out of the heating furnace is first rolled into a shape suitable for the intended product dimensions by a breakdown mill, which is a double rolling mill. Subsequently, the thickness of the coarse universal rolling mill group including the coarse universal rolling mill and the edger rolling mill is reduced, and the flange end portion is molded. Further, the flange is formed at a right angle by a finishing universal rolling mill to form an H-shaped product.
[0004]
As a method of forming an arc at the flange tip corner of the H-section steel by such a universal rolling method, there is a technique disclosed in Patent Document 1 described later. 6 and 7 show an outline of the rolling method of Patent Document 1. FIG. In this rolling method, a slab having a rectangular cross section and a rough steel slab are shaped and rolled into an H-shaped rough shaped material by a double roughing mill, and then predetermined by reverse rolling between a rough shaping rolling mill and an intermediate universal rolling mill. After forming the H-shaped intermediate material of the web thickness and flange width, the flange end of the H-shaped intermediate material is shaped into an arc with a double intermediate shaping rolling machine that can change the roll cylinder width of the upper and lower rolls, and then the roll cylinder H-shaped steel with a flange tip R is manufactured by finish rolling with a finishing universal rolling mill having vertical and horizontal rolls whose width can be changed.
[0005]
Further, Patent Document 2 to be described later discloses a technique in which the arc shape is imparted to the flange tip outer side and the inner side with different rolling mills. FIG. 8 shows an outline of this, and in this rolling method, a stepped portion for corner dropping provided on the roll of the rough universal rolling mill and a step for cornering provided on the roll of the shaping mill (edger) are shown. By rolling using a universal mill having a roll provided at the attached portion, an arc shape is given to the tip outside the flange.
[0006]
[Patent Document 1]
JP-A-6-297003 (FIGS. 6 and 7)
[0007]
[Patent Document 2]
Japanese Examined Patent Publication No. 2-15281 (FIG. 3)
[0008]
[Problems to be solved by the invention]
There are products with various flange thicknesses in H-section steel. For example, in the H600 × 300 series outer constant constant H-section steel, six types of products with flange thicknesses of 19 mm to 32 mm are manufactured. However, in the rolling method of Patent Document 1, since the arcs on both the inner and outer sides of the flange tip are provided with a single hole mold provided in the double intermediate shaping rolling mill, it is difficult to apply the R in the sizes having greatly different flange thicknesses. . For this reason, as a range in which the arc shape is formed at the flange tip, a narrow range such as a flange thickness of 15 mm to 18 mm is targeted, and it has not been a technique that can cope with a further significant flange thickness change.
[0009]
Moreover, in the rolling method of patent document 2, although the flange tip outer side is made into circular arc shape by the step part for corner dropping provided in the roll of the rough universal rolling mill, and the roll of the edger rolling mill, it is provided in the roll of the edger rolling mill. The size of the cut corners cannot be changed unless the roll is replaced. Therefore, when rolling sizes with different flange thicknesses, there is a problem that the outer side of the flange and the position of the angle drop portion are misaligned, so that it is not possible to make the outer end of the flange. For shape steel, it was necessary to replace at least the edger roll.
[0010]
The present invention has been made in order to solve the above-described problems, and has an H shape with a flange tip R that makes it possible to separately produce products of various types of flange thickness without changing the roll. It aims at providing the manufacturing method of steel, and its hot rolling apparatus row | line | column.
[0011]
[Means for Solving the Problems]
(1) The method for producing an H-shaped steel with a flange tip R according to the present invention comprises roughly rolling a raw steel piece into a roughly H-shaped rough shaped material by a rough shaped rolling mill, followed by a rough universal rolling mill and an edger rolling mill. In the method of manufacturing an H-shaped steel with a flange tip R, which is made into an intermediate rolled material having a predetermined web thickness, flange thickness and flange width by a rough universal rolling mill group consisting of: Using a roll equipped with a hole mold with a predetermined arc shape at the corner that rolls down the tip inside the flange as the roll of the machine, the tip inside the flange is formed into an arc shape, and the universal rolling mill group and finish universal rolling The tip on the outer side of the flange is formed into an arc shape by a rolling mill provided between the mills and having a roll having a variable hole mold width.
[0012]
(2) The method for manufacturing the H-shaped steel with flange tip R according to the present invention is such that, in the manufacturing method of (1), the hole mold width is variable according to the flange thickness and / or the flange width of the intermediate rolled material. Adjust the hole width of a rolling mill having a roll.
[0013]
(3) A hot rolling apparatus row of H-shaped steel with flange tip R according to the present invention includes a rough shaping rolling mill, a rough universal rolling mill group including a rough universal rolling mill and an edger rolling mill, and a finishing universal rolling mill. In the hot rolling apparatus row of H-shaped steel with a flange tip R having a flange, the roll of the edger rolling mill is a hole-shaped roll having a predetermined arcuate shape at a corner that squeezes the tip inside the flange. The rolling mill is disposed between the universal rolling mill group and the finishing universal rolling mill, has a roll having a variable hole mold width, and is provided with a rolling mill for forming the tip outside the flange of the material to be rolled into an arc shape. .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an overall configuration diagram showing an example of a hot rolling apparatus array according to an embodiment of the present invention. In the figure, 100 is a heating furnace, 110 is a rough shaping rolling mill (BD), 120 is a rough universal rolling mill, 130 is an edger rolling mill, 150 is a hole width variable rolling mill, and 160 is a finishing universal rolling mill. These are arranged in series. The coarse universal rolling mill 120 and the edger rolling mill 130 constitute a coarse universal rolling mill group 140, and the roll of the edger rolling mill 130 has a hole shape in which a corner that presses down the tip inside the flange has a predetermined arc shape. Is formed, and the tip inside the furan is molded into an arc shape (R is given). Moreover, the hole width variable rolling mill 150 is disposed between the rough universal rolling mill group 140 and the finishing universal rolling mill 160, and the roll is supported so as to be movable in the axial direction, and moves the roll. Thus, the width (interval) of the hole mold formed in the roll is adjusted according to the thickness of the flange, and the outer end of the flange is molded into an arc shape (R is given).
[0015]
In general, H-shaped steel uses a slab having a rectangular cross section as a raw material or a steel piece previously cast or rolled into a substantially H-shaped cross section, and is subjected to rough universal rolling by a rough shaping rolling mill 110 having upper and lower rolls having several hole shapes. Roll a rough steel slab with a shape suitable for the above. Subsequently, in rough universal rolling, the thickness of the flange and the web is reduced by the rough universal rolling mill 120, and the edge of the flange is reduced by the edger rolling mill 130, and the flange width is adjusted to be close to the target product. Rolled to dimensions.
[0016]
FIG. 2 is a schematic view of the flange inner side rolling with the edger mill 130 of FIG. The edger rolling mill 130 is formed with arc-shaped hole molds 133a, 133b and 134a, 134b having a radius R1 at the portion of the upper and lower rolls 131, 132 that are pressed down to the tip inside the flange. The tip corner is molded into an arc shape (R is given).
[0017]
FIG. 3 is a schematic diagram of flange outer R rolling with the variable hole width rolling mill 150 of FIG. 1, and FIG. 4 is a schematic diagram of flange outer R rolling when the flange thickness of the material to be rolled is different. As described above, the hole width variable rolling mill 150 is installed between the rough universal rolling mill group 140 and the finishing universal rolling mill 160. The rolling mill 150 includes rolls 151 and 152 as upper rolls and rolls 153 and 154 as lower rolls. And the space | interval of the rolls 151 and 152 and the space | interval with the rolls 153 and 154 are each supported so that adjustment is possible. Further, these rolls 151 to 154 are provided with hole molds 155a, 155b and 156a, 156b provided with an arc R2 so that the outer end of the flange can be attached with R, and these hole molds 155a, 155a, 155b and 156a, 156b are in contact with the material to be rolled on the outside of the flange to which R is attached, and the inside of the flange has a shape that is not constrained. When the flange thickness changes greatly, for example, when rolling the size of tf2 whose flange thickness is smaller than tf1 of FIG. 3, when rolling with the same hole width as that of FIG. 3, FIG. 4 (a) shows. Thus, the outer end of the flange does not come into contact with the R portion of the hole type. Therefore, by reducing the distance between the rolls 151 and 152 and the distance between the rolls 153 and 154 from A1 in FIG. 4A to A2 (A2 <A1) in FIG. 4B, the hole molds 155a and 155b The gap (hole width) and the gap (hole type) between the hole molds 156a and 156b are respectively adjusted, and the tip of the flange outer side can be rounded in the same manner as in the case where the flange thickness in FIG. 3 is tf1. . Although this example is an example when the flange thickness is changed, the same processing is performed when the flange width is changed.
[0018]
Also in the technique of the above-mentioned Patent Document 1, as in the present embodiment, a rolling mill capable of varying the hole width is provided at a position between the rough universal rolling mill group 140 and the finishing universal rolling mill 160 to provide a flange tip. However, in the technique of Patent Document 1, R is applied simultaneously to both the inside and outside corners of the flange with this rolling mill. For this reason, it was only possible to apply R in a narrow range where the change in flange thickness was within 3 mm. On the other hand, in this embodiment, by attaching the R inside of the flange and the outside R attaching with separate rolling mills, the R attaching is performed corresponding to a wider range of flange thickness change. Is possible. That is, the inner radius of the flange can be provided by the edger mill 130 regardless of the flange thickness, and the outer radius R of the flange width can be adjusted according to the amount of change in the flange thickness. By adjusting, it can provide easily. The range in which the flange thickness changes is not particularly limited as long as it is within the range in which the hole width can be adjusted. For example, if the hole width adjustment range is 50 mm, the change range of the flange thickness that can be rounded is up to 50 mm. For this reason, if the flange thickness change range of the H600 × 300 series exemplified above is 19 to 32 mm, it is possible to perform the R attachment without any problem at all flange thickness sizes.
[0019]
In addition, the radius of the flanged end of the flange may be the same on the inside and outside of the flange, or may be different from each other. The radius of the R-attach can be easily changed by changing the radius of the R-attachment portion of the hole mold provided in the edger mill 130 and the variable hole width mill 150. If the sum of the R radii of the inside and outside of the flange is within a range that does not exceed the minimum flange thickness in the target product, it can be freely adjusted.
[0020]
FIG. 5 is a schematic view showing a cross-sectional shape of a flange-shaped R-shaped H-section steel finish-rolled by a finishing universal rolling mill. The material to be rolled that has been rounded to the flange tip is conveyed to the finishing universal rolling mill 160, and becomes a product having a cross-sectional shape shown in FIG. As long as the web height varies depending on the flange thickness, the finishing universal rolling mill 160 may use a roll having a fixed horizontal roll width. Moreover, when manufacturing H method steel with a constant outer method, a roll whose width can be adjusted is used as a horizontal roll of the finishing universal rolling mill 160, and the web height of the material to be rolled is constant by adjusting the roll width. Adjust the product dimensions so that In addition, a technique for making a web outer dimension constant by disposing a web height adjusting rolling mill in front of the finishing universal rolling mill 160 is disclosed, and even in such a method, the web height dimension is constant. It is possible to
[0021]
As described above, according to the present embodiment, the inner edge of the flange is rounded by the edger mill 130 in the rough universal rolling process, and the outer side of the flange is removed by the hole width variable rolling mill 150 installed in front of the finishing universal mill 160. Therefore, it is possible to perform the R-end of the flange tip in a multi-size H-section steel having significantly different flange thicknesses. In this embodiment, the example in which the roll width (hole width) of the variable hole width mill 150 is adjusted according to the flange thickness of the intermediate rolled material has been described. The roll width (hole width) of the hole width variable rolling mill 150 may be adjusted according to the thickness and the flange width.
[0022]
【Example】
As a first example of the present invention, a H-shaped steel with a flange tip R was rolled using a hot rolling facility for the shaped steel shown in FIG. Here, the target product dimensions were a web height of 600 mm and a flange width of 300 mm, and rolling was performed on two types: a web thickness of 12 mm, a flange thickness of 19 mm, a web thickness of 16 mm, and a flange thickness of 32 mm. In addition, R with a radius of 5 mm was given to the flange tip both on the inside and outside.
[0023]
Using a beam blank cast in a substantially H shape as a raw material, and using a plurality of hole molds of the rough shaping rolling mill 110 as a rough shaping material, reverse rolling by the rough universal rolling mill group 140 to a predetermined thickness and flange width At the same time, R attachment was performed by arc-shaped hole molds 133a, 133b, 134a, 134b provided on the rolls 131, 132 of the edger rolling mill 130 at the inner end of the flange. Next, this intermediate rolled material was rolled in one pass by a variable hole width rolling mill 150 provided between the rough universal rolling mill group 140 and the finishing universal rolling mill 160, and R was attached to the outer end of the flange. Finally, the finish universal rolling mill 160 performs rolling for one pass, so that the flange slope is vertical and the H-shaped steel with a flange tip R is obtained. As a result of rolling by the above method, a narrow flange width H-shaped steel having a target size of R of 5 mm could be rolled at the flange tip regardless of whether the flange thickness was 19 mm or 32 mm.
[0024]
On the other hand, as a comparative example, a method of manufacturing H-shaped steel of the same size with the rolling equipment of Patent Document 1 shown in FIG. 6 was examined. In order to produce an H-shaped steel with a flange thickness of 32 mm, the width of the groove formed in the roll of the double intermediate shaping mill was set to 33 mm. When R-shaped with a radius of 5 mm is applied to the flange tip with this hole type, R-shaped is possible with an H-section steel with a flange thickness of 32 mm, but with an H-section steel with a flange thickness of 19 mm, the gap between the flange and the hole mold is in the thickness direction. Therefore, it is impossible to roll the target H-shaped steel with a flange tip R at both flange thicknesses.
[0025]
【The invention's effect】
As described above, according to the present invention, it is possible to give a desired arc shape to the front end of the flange inner surface and the outer surface without performing roll recombination when rolling a plurality of H-shaped steels having greatly different flange thicknesses. Thus, H-shaped steel with flange tip R of various sizes can be manufactured at low cost.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing an example of a shape steel hot rolling facility according to an embodiment of the present invention.
FIG. 2 is a schematic view of flange inner radius rolling by the edger rolling mill of the present embodiment.
FIG. 3 is a schematic diagram of flange outer R rolling with the variable hole width rolling mill of the present embodiment.
FIG. 4 is a schematic diagram of flange outer R rolling when the flange thickness of the material to be rolled is different by the variable hole width rolling mill of the present embodiment.
FIG. 5 is a schematic view showing a cross-sectional shape of an H-section steel with a flange tip R.
6 is a schematic view showing a rolling method of H-shaped steel with flange tip R in Patent Document 1. FIG.
FIG. 7 is a schematic view showing a hole shape of a double intermediate shaping rolling machine in which R is attached to the flange tip in the H-shaped steel with flange tip R of Patent Document 1.
FIG. 8 is a schematic view showing a rolling method of H-section steel with flange tip R in Patent Document 2.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 Heating furnace 110 Rough shaping rolling mill 120 Rough universal rolling mill 130 Edger rolling mill 140 Rough universal rolling mill group 150 Pore width variable rolling mill 160 Finish universal rolling mill

Claims (3)

A raw steel piece is roughly rolled into a roughly H-shaped rough shaped material by a rough shaping rolling mill, and then a predetermined universal web thickness, flange thickness, and flange width are obtained by a rough universal rolling mill group consisting of a rough universal rolling mill and an edger rolling mill. In the method of manufacturing the H-shaped steel with a flange tip R, which is an intermediate rolled material, and then finish-rolled with a finish universal rolling mill,
Using a roll provided with a hole mold having a predetermined arc shape at the corner for rolling down the tip inside the flange as a roll of the edger rolling mill, the tip inside the flange is formed into an arc shape, A method for producing an H-shaped steel with a flange tip R, wherein the tip on the outer side of the flange is formed into an arc shape by a rolling mill provided between finishing universal rolling mills and having a roll having a variable hole width. 2. The flange tip R-attached H according to claim 1, wherein a hole width of a rolling mill having a roll having a variable hole width is adjusted according to a flange thickness and / or a flange width of an intermediate rolled material. A method of manufacturing shape steel. In the hot rolling apparatus for the H-shaped steel with a flange tip R having a rough shaping rolling mill, a rough universal rolling mill group consisting of a rough universal rolling mill and an edger rolling mill, and a finishing universal rolling mill,
The roll of the edger rolling mill consists of a roll having a hole shape having a predetermined arc shape at the corner that presses down the tip inside the flange, and is arranged between the rough universal rolling mill group and the finishing universal rolling mill, A hot rolling device row of H-section steel with flange tip R, which has a roll having a variable hole width and provided with a rolling mill for forming the tip of the outer side of the flange of the material to be rolled into an arc shape.

Images