JPH0780503A - Rolling method for shape having flange - Google Patents

Abstract

PURPOSE:To manufacture a high-quality product without web buckling, center deviation and overlap in fillet parts even when reduction is relatively larger at the time of reducing the web height of shapes having flanges such as a wide flange shape during rolling. CONSTITUTION:At the time of reducing the web height with an universal mill FU having variable barrel-width horizontal rolls in finish rolling stage, excess metals 18 are formed in both end parts of web by providing recessed parts on the circumferential surfaces at both right and left ends of the upper and lower horizontal rolls 2H of the universal mill RU in intermediate rolling stage 2. In accordance with the reduction of web height and rolling reduction of excess metal parts with the finishing universal mill FU, the moving amount of the vertical rolls Fv of the finishing universal mill FU toward the outlet side or inlet side of rolling is adjusted so as to make contact starting position between the horizontal roll FH and the excess metals 18 match the contact starting position between the vertical rolls Fv and the outer side face of the flanges 1a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flange-shaped profile, such as H-section steel, channel steel and similar metallic or non-metallic profiles, and particularly H-section steel, for efficiently increasing the web height without any defect in shape. The present invention relates to a rolling method for selectively and separately producing.

[0002]

2. Description of the Related Art Universal rolling mills are mainly used for rolling a profile having a flange, for example, an H-section steel. As shown in FIG. 4, in the conventional rolling method, since the horizontal roll 2H having the same cylinder width is used in the same series, the web inner width WB of the H-section steel becomes constant, and when the flange thickness tF is different,
Since the web height W changes accordingly, the web heights will be different even though they are in the same series. When such rolled H-section steels are joined to each other to form a beam for a building structure, the outer surfaces of one flange are usually aligned with each other, resulting in a displacement of twice the flange thickness, which is inconvenient for construction. Further, the coating thickness of the steel-framed reinforced concrete varies depending on the size, which is inconvenient in design. Therefore, the conventional rolling H
Shaped steel has some surfaces that are difficult to use depending on the application such as building columns and beams, beams and beams, and column and column joining. Rolling with a constant web height W in the same series as shown in Fig. 5 The production of H-section steel has been strongly desired.

To meet this demand, Japanese Patent Publication No. 1-472
No. 41 and Japanese Patent Application Laid-Open No. 2-6001, as one of means for adjusting the web height of H-section steel within the same roll chance, the web height of the intermediate rolled material after rough universal mill rolling is finish-rolled. A rolling method of reducing in a process, a so-called web height reducing rolling method is disclosed.

In this web reduction rolling method, a finish universal rolling mill having a pair of upper and lower horizontal rolls and a pair of left and right vertical rolls having variable roll widths is arranged, and when H-section steel is rolled by the rolling mill. Sets the width of the horizontal roll smaller than the inner width of the H-section steel, and sets the gap between the vertical roll and the side of the horizontal roll (vertical roll gap) in accordance with the product flange thickness. Is a rolling method for adjusting the web height of the profile by reducing the web-corresponding part from the width direction. This rolling means is a practical means capable of easily adjusting the web height of the profile with relatively inexpensive equipment investment. However, since the ratio of the thickness tw to the inner width WB (the slenderness ratio) of the web portion is relatively large, the web is likely to buckle as shown in FIG. 6 when the inner web width reduction amount is large. Also,
The restraint of the material to be rolled by the vertical rolls precedes the restraint of the material to be rolled by the horizontal rolls, the guiding action of the material to the regular position by the horizontal rolls is reduced, and in synergy with the buckling of the web, as shown in FIG. As described above, there is a drawback that the center deviation e of the web becomes very large. In recent years, with the progress of labor saving and automation at construction sites, it has been demanded that the rolled H-section steel, which is a member, have a high dimensional accuracy, in particular, a high center deviation of the web. Is a serious problem.

This center deviation e improves the guiding accuracy of the material to be rolled to the finishing universal rolling mill by devising the structure of the guide, and adjusts the flange reduction ratio in the finishing universal rolling mill to devise the overall stretching balance. By
Although it can be improved to some extent, the reduction amount of the web height cannot be increased so much practically because of the basic mechanism of forming. Against this background, as inventions for changing the molding mechanism, JP-A-3-94903 and JP-A-3-94903 have been proposed.
216201, JP-A-3-268802,
JP-A-4-172102 and JP-A-2-14
Each means described in Japanese Patent No. 7102 has been proposed.

In Japanese Patent Laid-Open No. 3-94903, the shape of the fillet portion of the material is preformed so that a part of the horizontal roll comes into contact with the material to be rolled over a portion or the entire area of the flange projected contact length of a predetermined ratio or more. By moving the point of buckling at the time of shrinking the web from the fillet portion to the central portion of the web, center deviation is suppressed.

In Japanese Patent Laid-Open No. 3-216201, the center deviation is suppressed by carrying out reduction rolling using a material in which the shape of the fillet portion is preformed so that the projected web contact length is equal to or longer than the projected flange contact length. That is. As the horizontal roll of the finishing universal rolling mill, one having a fixed cylinder width or one having an adjustable width is used.

Japanese Unexamined Patent Publication (Kokai) No. 3-268802 discloses that 10 ° ≦ θ ≦ 60 ° and R ₁ ≧ r and R ₂ ≧ r, where θ: an angle R ₁ formed by a linear portion of the fillet portion with respect to the web surface: the fillet portion and the flange inner surface and the coupling portion of the arc radius R _2: performs reduction rolling using a preformed material fillet shape so as to satisfy the arc radius of the coupling portion between the fillet portion and the web surface This suppresses the center deviation. As the horizontal rolls of the finishing universal rolling mill, those which are fixed by the cylinder width or whose width can be adjusted are used.

[0009] In all of the above publications, the horizontal rolls at the time of web height reduction rolling are aimed at suppressing the buckling of the web as small as possible and moving the buckling occurrence position from the fillet portion to the central portion of the web. Proposed to determine the shape of the fillet so that the web restraint range is equal to or longer than the flange projected contact length.

However, when the proper shape of the fillet portion is determined as described above, the web projected contact length becomes extremely longer than the flange projected contact length and the horizontal roll comes into contact with the web when the height reduction amount is small. During the period from the start to the start of the web height reduction, the web is independently rolled without the horizontal roll restraint (guide). For this reason, the material is rolled in an extremely unstable state, and in extreme cases, the material is flowed to either the left or right side, and during the subsequent web height reduction rolling, the reduction amount on one side becomes extremely large. As a result, as shown in FIG. 8, a fold flaw PL is generated in one of the fillet portions.

Further, Japanese Patent Laid-Open No. 4-172102 discloses
By performing the web height reduction rolling in a state where the axis of the vertical roll is shifted to the delivery side of the rolling mill with respect to the axis of the horizontal roll, the reduction adjustment amount of the inner width of the web is significantly increased. In this publication, the vertical roll shift amount is defined as a range of 3 to 30 mm, but this shift range is insufficient depending on rolling conditions, and web buckling and center deviation occur.

Japanese Unexamined Patent Publication (Kokai) No. 2-147102 also proposes performing the web height reduction rolling in a state in which the axis of the vertical roll is shifted to the delivery side of the rolling mill with respect to the axis of the horizontal roll. However, the vertical roll shift amount in this case is 400 to 6
It is as large as 00 mm, and the web height reduction rolling is performed in a state where the web reduction and the flange reduction are performed separately, and thus web buckling, web waves, and plate thickness deviation are likely to occur.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the prior art, and a relatively large reduction in the web height of the material to be rolled can be achieved without replacement of the roll tool. It is an object of the present invention to provide a method for rolling a profile having a flange capable of producing a high-quality product which can be carried out under the conditions described above and which does not have buckling of the web, center deviation, and fold flaws in the fillet portion.

[0014]

The gist of the present invention is a rolling method for reducing the web height of a profile in a universal rolling process of a profile having a flange consisting of a rough rolling process, an intermediate rolling process and a finish rolling process. In, after forming a surplus at both ends of the web of the profile with at least one or more universal rolling mills in the intermediate rolling step, depending on the web height reduction amount and the reduction amount of the surplus thickness in the finish rolling step, Move the vertical roll position of the universal rolling mill in the finish rolling process to the rolling out side or rolling in side so that the contact start position between the horizontal roll and the excess thickness and the contact start position between the vertical roll and the outer surface of the flange are approximately the same. A method for rolling a profile having a flange is characterized in that the web height reduction rolling is performed.

[0015]

The method of the present invention will be described in more detail below with reference to FIGS. 1 and 2. FIG. 1 illustrates the basic rolling process of the present invention. That is, the rough rolling machine BD of the rough rolling step 1 for supplying the beam blank 4 and the concave portion (notch portion) for rolling the beam blank 4 into a substantially H shape and forming the extra thickness 18 at both ends of the web 2a. ) Is formed on each of the left and right circumferential surfaces of the upper and lower horizontal rolls 2H, the universal rolling mill RU of the intermediate rolling process 2; the edger rolling mill E of the intermediate rolling process 2 that forms the width F of the flange portion 1a; This is a rolling process constituted by the finishing universal rolling mill FU of the finishing rolling step 3 having a horizontal roll having a mechanism and a vertical roll having a position changing mechanism to the rolling exit side or the rolling entrance side.

Next, the rolling method of the present invention using the above rolling process will be described. The basic idea of the present invention is that the contact start position between the horizontal roll and the excess thickness is substantially coincident with the contact start position between the vertical roll and the flange outer side surface in accordance with the reduction amount of the web height and the reduction amount of the excess thickness. Thus, the amount of movement of the vertical roll position of the universal rolling mill in the finish rolling process to the rolling-out side or the rolling-in side is adjusted. It should be noted that the extra thickness was added to both ends of the web because the contact length between the horizontal roll and both ends of the web was made close to the contact length between the vertical roll and the flange, and the vertical roll movement amount was made as small as possible to thereby move the vertical roll. This is to facilitate facility equipment design.

The advantages of the method of the present invention will be described below with reference to FIGS. 2 (a) and 2 (b). FIG. 2 (a) schematically shows a situation in which web reduction rolling with a reduction amount ΔWr is performed by the conventional universal rolling method. In this case, the vertical roll Fv is not moved to the rolling-out side,
Further, since the contact length Lf between the outer surface of the flange 1a and the vertical roll Fv is longer than the contact length Lw between the surplus thickness 18 and the horizontal roll FH, the web height can be increased in a situation where the surplus thickness 18 is not pressed down by the horizontal roll FH. A region for contraction occurs, and the compressive force P acts on the central portion of the web in the region. When this compressive force P exceeds the buckling limit stress of the web, buckling B of the web occurs.

On the other hand, FIG. 2B shows the reduction amount Δ according to the present invention.
Fig. 3 schematically shows a situation in which Wr web height reduction rolling is performed. In this case, the vertical roll is moved to the rolling-out side by a predetermined amount d so that the start of contact between the outer surface of the flange 1a and the vertical roll Fv coincides with the start of contact between the extra thickness 18 and the horizontal roll FH. Therefore, the web height is reduced while pressing the extra thickness 18 with the horizontal roll FH, and the compression force P acting on the web does not reach the central portion of the web. Therefore, it is possible to prevent buckling of the central portion of the web and roll a product with good center deviation accuracy. However, if the vertical rolls are moved more than necessary to the rolling-out side, only the web is rolled in the state where the flange is not restrained in the initial stage of rolling, and the position of the material to be rolled is biased to the left or right from the normal position. Since the web height reduction rolling is performed, either the right or left web height reduction amount may be abnormally large, and the center deviation may be rather large.

Therefore, the proper moving amount of the vertical roll Fv is determined as follows. In FIGS. 3A and 3B, the web projection contact length Lw can be generally expressed by the equation (1).

[Equation 1] The flange projected contact length Lf can be expressed by equation (2).

[Equation 2] Under the condition that the contact start position between the horizontal roll FH and the extra thickness 18 is made to substantially coincide with the contact start position between the vertical roll Fv and the outer surface of the flange 1a, an appropriate vertical roll movement amount d is expressed by the formula (3). You can

D = Lf−Lw …………………………………… (3) Here, when d is a positive value, the vertical roll Fv is provided on the rolling exit side.
And when d is a negative value, the vertical roll is moved to the rolling entry side.

[0021]

[Examples] Specifically, when manufacturing H-section steel with a constant web height in the series, the inner web width is constant for all sizes up to the intermediate rolled material formed in the intermediate rolling process. Based on the web height of the thinnest flange thickness in the rolled material, and for the flange thickness thicker than that, only the predetermined reduction amount (twice the difference between the target material flange thickness and the reference material flange thickness) Reduce web height. This reduction of web height is performed by using a finishing universal rolling machine in which the cylinder width of the horizontal roll is variable. That is,
The cylinder width of the horizontal roll is set narrower by a predetermined reduction amount with respect to a reference value, and when the intermediate rolled material is rolled by a finish universal rolling mill, the vertical roll is pressed down in the web height direction to reduce the web height. Is adjusted to the required size.

In the following, product designation series H550 × 2
An example in which the present invention is applied to rolling an H-shaped steel having a constant web height of No. 00 will be described. First, the web thickness and flange thickness are (6 mm x 9 mm), (6 mm x 12 mm), (6
mm × 16mm), (9mm × 16mm), (9mm × 19mm),
(9 mm x 22 mm), (12 mm x 16 mm), (12 mm x 1
9 mm), (12 mm × 22 mm), and (12 mm × 25 mm) product sizes corresponding to product sizes were rolled in the intermediate rolling step 2 to a required thickness. At this time, the extra thickness 18 was also formed at both ends of the web 2a of the intermediate rolled material by the upper and lower horizontal rolls 2H having concave portions formed on the circumferential surfaces on both the left and right sides. Here, within the above target size, the standard size is (6 mm x 9 m
m), and the size with the largest reduction in web height is (12 mm × 25 mm), so the reduction in web height ΔW
The maximum value of r is (difference in flange thickness) x 2 = (25-9)
× 2 = 23 mm. Therefore, the size (12 mm x 2
5mm), the horizontal width of the cylinder is 5
Set the web height reduction amount 32mm smaller than 32mm,
Rolling was performed by a finishing universal rolling mill FU in which the gap between the vertical roll and the side surface of the horizontal roll was set so that the flange thickness after rolling was 25 mm. The vertical roll movement amount d in this case is
From formulas (1) to (3), the rolling-out side was set to about 62 mm. However, in this case, the excess thickness reduction Δtw is 6 mm, the horizontal roll radius RH is 700 mm, and the vertical roll radius Rv is 500 mm. Similarly, for web size reductions smaller than the maximum value, the horizontal roll cylinder width is set smaller than the reference cylinder width 532 mm by the web height reduction amount.
The gap between the vertical roll and the side surface of the horizontal roll is set in accordance with the desired flange thickness, and the vertical roll is moved by the amount calculated by the equations (1) to (3) and rolled by the finish universal rolling mill FU. . As a result, it was possible to perform H-section steel with a constant web height of product designation series H550 × 2 without changing the rolls. Furthermore, the rolling is extremely stable,
The product had a small center deviation due to web buckling, and had good quality with no remaining excess thickness and no flaws on the fillet portion.

[0023]

According to the present invention, the web height of a profile having a flange can be reduced without replacing the roll tool, so that the web height can be kept constant even if the flange thickness is different in the same series. Can be built. Further, it is possible to suppress the deviation of the center of the web and the flaws in the fillet portion, which are feared in the conventional reduction rolling, and it is possible to manufacture a high-quality product.

[Brief description of drawings]

FIG. 1 is a schematic diagram of the basic process of the present invention.

FIG. 2A is a schematic view of a web height reduction rolling state by a conventional universal rolling method. (B) The schematic diagram of the web height reduction rolling condition by this invention.

3A and 3B show a positional relationship between a roll and a material to be rolled during web height reduction rolling according to the present invention. (A)
Is a cross section of a horizontal roll portion, and (b) is a schematic plan view.

FIG. 4 is a schematic view showing a conventional universal rolling method.

FIG. 5 is a cross-sectional view showing a product shape of rolled H-section steel.

FIG. 6 is a schematic diagram showing a defective forming situation in a finish rolling process.

FIG. 7 is a cross-sectional view showing a product shape of rolled H-section steel in which dimension / shape defects occur.

FIG. 8 is a schematic diagram showing a defective rolling condition in a finish rolling process.

[Explanation of symbols]

 1 rough rolling process 2 intermediate rolling process 3 finish rolling process 4 beam blank 18 surplus BD rough rolling machine RU universal rolling machine of intermediate rolling process E edger rolling machine of intermediate rolling process FU finishing universal rolling machine

Claims (1)

[Claims] 1. A rolling method for reducing the web height of a profile in a universal rolling process of a profile having a flange comprising a rough rolling process, an intermediate rolling process and a finish rolling process, wherein at least one of the intermediate rolling processes is used. After forming excess thickness on both ends of the web of the profile with the above universal rolling machine,
According to the amount of reduction of the web height reduction and the amount of excess thickness in the finish rolling step, the vertical roll position of the universal rolling mill in the finish rolling step is moved to the rolling exit side or the rolling entrance side,
A method for rolling a profile having a flange, characterized in that the web height reduction rolling is performed by substantially matching the contact start position between the horizontal roll and the excess thickness and the contact start position between the vertical roll and the flange outer surface.