JP2530405B2 - Method for hot rolling channel steel and rolling apparatus train - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to universal rolling of channel steel, and more particularly to improving the size and shape of the invert material for shipbuilding obtained by dividing channel steel into two and improving rolling efficiency. The present invention relates to a rolling method and rolling apparatus train.

[0002]

2. Description of the Related Art A channel steel manufactured by a hot rolling method is used for general building structures, and the web portion of the channel steel is divided into two parts in the length direction of the product so that the unequal thicknesses are not equal. Angle steel (hereinafter,
It is known that it is used as a shipbuilding material. The invert used for shipbuilding materials needs to satisfy various standards defined by JIS, but the shape of the flange tip portion is particularly problematic in roll forming. That is, in order to improve the paint adhesion of the flange tip, as shown in FIG.
It is desired that the arc is formed in a predetermined arc R ₁ defined by IS, and the arc R ₂ outside the flange tip is formed in any arc within a range that can satisfy paint adhesion.

The channel steel used as the material for the invert is generally manufactured by the universal rolling method. As a means for improving the shape of the above-mentioned flange tip, the applicant of the present invention has previously described the Japanese Patent Publication No. The technology of 15281 is proposed. FIG. 5 shows an example of a rolling line for carrying out the conventional method, which is composed of a rough rolling mill 1, an intermediate universal rolling mill 2, an edger 3 and a finishing universal rolling mill 4 (or a double rolling mill 4 '). 6 (a) and 6 (b) show the rolling method, in which the rough shaped billet 5 rolled by the rough rolling mill 1 is used.
Is made into an intermediate rolled material 6 by an intermediate universal rolling mill 2 consisting of horizontal rolls H and vertical rolls V, then the flange end is formed by an edger 3, and finish rolling is carried out by a finish universal rolling mill 4 or a double rolling mill 4 '. The product of the channel steel 9 of FIG. The invert 10 is a final product obtained by dividing a web of channel steel 9 into two in the length direction indicated by imaginary lines.

The characteristic of this conventional method is that the vertical roll V of the intermediate universal rolling mill 2 is provided with a step portion Q ₁ for corner removal outside the flange tip of the material to be rolled, and the horizontal roll E of the edger 3 is stepped. Part Q ₂ and also the stepped part Q _{3 on} the horizontal roll H of the finishing universal rolling mill 4 or the double rolling mill 4 ′.
Was provided, and the tip of the flange was formed in a smooth arc shape. Although the shape of the tip of the flange is considerably improved by this conventional means, when the metal flow of the material being rolled during rolling is not appropriate, the gap p between the horizontal roll H and the vertical roll V ′ of the finishing universal rolling mill 4 becomes “ Biting out "
Or, on the contrary, when the amount of meat is insufficient, a pointed shape defect called “sharp edge” may occur. In addition, the intermediate universal rolling mill 2
Since the cylinder widths S1 and S2 of the lower horizontal roll of the finishing universal rolling machine 4 or the double rolling machine 4'are constant, the cylinder widths S1 and S2 become smaller as the wear of the rolls progresses, and the dimensional tolerances can be satisfied. When it disappears, it is necessary to replace the roll, and the unit consumption of the roll is reduced, and there is a problem that the work efficiency is reduced due to the roll replacement.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the problems in the conventional method for producing channel steel by the universal rolling method described above, and forms a good arc shape without biting out of the flange tip or lack of thickness. The purpose is to improve the roll unit and rolling efficiency.

[0006]

The gist of the present invention is as follows. A slab or rough shaped steel slab with a rectangular cross section is roughly shaped into a groove-shaped rough shaped material by a double rough rolling machine, and then reverse rolling between a rough shaping rolling mill and an intermediate universal rolling mill is performed to obtain a predetermined web thickness and width. After forming the channel-shaped intermediate material, the upper end of the flange of the groove-shaped intermediate material is formed into an arc shape with a double intermediate shaping rolling machine that can change the roll cylinder width of the upper and lower rolls, and the roll cylinder width can be changed. A method for hot rolling channel steel for finish rolling with a finish universal rolling machine having horizontal rolls; It consists of a double rough rolling machine with a plurality of rough forming cavities, an intermediate universal rolling machine and a rough shaping rolling machine that are arranged in close proximity to each other for continuous rolling, and upper and lower rolls with variable roll widths. A flange forming and rolling machine in which a groove is formed in one of the upper and lower rolls, and a stepped portion that presses the flange outer corner is formed in the other roll, and a finishing universal that has upper and lower horizontal rolls with variable roll widths. A row of hot rolling apparatus for channel steels in which rolling mills are arranged in sequence; The groove shape described above, which is a pair of oblique rolls in which the axial centers of the upper and lower rolls of the flange forming mill are adjustable within a plane horizontal to the rolling direction and at a predetermined angle θ _H with respect to a plane vertical to the rolling direction. In the hot rolling mill train for steel.

The present invention will be described in detail below with reference to the drawings. FIG. 1 shows an apparatus train of the present invention, in which a double rough rolling machine 1 roughly rolls a slab or a rough shaped steel slab having a rectangular cross section into a rough shaped material. The intermediate universal rolling mill 2 is disposed in close proximity to the rough shaping rolling mill 3 so that continuous rolling is possible, and reverse rolling is performed to form an intermediate material having a predetermined web thickness and width. The flange forming and rolling machine 20 is unique to the present invention as will be described later in detail, and is configured such that the roll body width of the upper and lower rolls can be changed, and the flange tip end portion of the intermediate material is formed in an arc shape.
The finish universal rolling mill 21 has vertical left and right rolls and upper and lower horizontal rolls whose roll body width can be changed. The intermediate rolling step in which the intermediate universal rolling mill 2 and the rough shaping rolling mill 3 constitute one set may optionally be provided in plural sets.

Next, the details of the method of the present invention will be described with reference to a roll hole type example of each rolling mill shown in FIG. The slab 40 having a rectangular cross section is a material used in the present invention, and is roughly rolled by the double rough rolling machine 1 through edging in the slab width direction (not shown). The double rough rolling mill 1 is composed of upper and lower horizontal rolls 1a and 1b, and has a plurality of rough shaping hole dies K1, K2, K3 engraved on the rolls.
Rough shaped material 5 with groove-shaped cross section by reverse rolling
Roughly model. When using a crude steel billet instead of the slab material, the edging process is unnecessary, so rolling is performed from the hole die K1.

Subsequently, the rough molding material 5 is the upper and lower horizontal rolls 2.
a, 2b and the left and right vertical rolls 2c, the intermediate universal rolling mill 2 and the rough shaping rolling mill 3 including the upper and lower horizontal rolls 3a, 3b perform reverse rolling to obtain an intermediate material. The intermediate universal rolling mill 2 and the rough shaping rolling mill 3 are arranged in close proximity to each other so that reverse rolling and continuous rolling are possible. This is to do well. Further, the intermediate rolling process including the intermediate universal rolling mill and the rough shaping rolling mill in the present invention is provided with a second intermediate rolling process in which the intermediate universal rolling mill 21 and the rough shaping rolling mill 31 are set as one set as shown in the illustrated example. That is optional. Whether to use one set or two sets in the intermediate universal rolling process can be arbitrarily selected according to conditions such as a pass schedule and rolling function. In this intermediate rolling process, the final product of rolling is formed into an intermediate material 7 having a channel steel web thickness and a flange width built therein.

Next, the flange portion of the intermediate material 7 is formed by the flange forming and rolling machine 20. The upper roll 20a and the lower roll 20b of the flange forming and rolling machine 20 are configured such that the roll body width can be arbitrarily changed in the left-right direction, and the lower roll 20b is provided with a groove 20c.
FIG. 4 is a partially enlarged view of the concave groove 20c. The hole bottom of the concave groove is formed in an arc shape, and the radius R thereof is indicated by an imaginary line, and the flange thickness t ₁ is the thickest among the channel steels rolled by the roll. It is set to a size corresponding to R of the product size 8a.
The left and right upper rolls 20a are formed with stepped portions having a predetermined R on their inner surfaces in order to press the flange outer corners of the channel steel.

FIG. 3 shows another embodiment of the flanging and rolling mill 20, in which the upper and lower rolls 20a, 20b (lower roll 2
0b is omitted because it overlaps with the upper roll 20a in the drawing.) The axis S has a predetermined angle θ with respect to a plane P horizontal to the rolling direction (arrow direction) and perpendicular to the rolling direction.
_It is a skew roll that can be adjusted to _H. Such an oblique roll method is a rolling means proposed by the applicant of the present application as a means for expanding the web height of H-section steel, for example, in Japanese Patent Publication No. 3-42122, and as will be described later, it is applied to the channel steel rolling of the present invention. By adopting this skew roll system, an effect different from the expansion of the web height of the H-section steel is obtained.

The finish universal rolling mill 21 has an upper horizontal roll 21a and a lower horizontal roll 21 whose roll body width can be changed.
b and left and right vertical rolls 21c, the both ends of the web of the material to be rolled are sandwiched by the upper and lower horizontal rolls 21a and 21b, and the left and right vertical rolls 21c press the flange surface so that the flange outer surface is orthogonal to the web surface. Rolled and
The final rolled product is channel steel 9.

[0013]

[Operations and Examples] The rough roughing material 5 having a groove shape is roughly shaped by the double roughing mill 1 and predetermined by reverse rolling with the rough shaping mills 3, (31) and the intermediate universal mills 2, (21). The process up to the step of forming the groove-shaped intermediate member 7 having the web thickness and width is the same as the technique of Japanese Patent Publication No. 2-15281 of the conventional means. The present invention is characterized by the operation after the intermediate rolling. That is, since the hole shape formed by the stepped upper roll 20a and the lower roll 20b having the concave groove of the flange forming rolling machine 20 is a so-called bag hole type, the flange portion of the material to be rolled can be formed without excess or deficiency. It will be possible. In particular,
Since the hole bottom of the concave groove formed in the lower roll 20b is provided with an appropriate radius, the shape of the flange tip portion is remarkably improved, and due to biting out of the flange tip portion and lack of thickness in the conventional universal rolling method. It is possible to prevent the occurrence of shape defects such as sharp edges.

In FIG. 4, even in the case of a product having the smallest flange thickness t ₂ among the channel steels rolled by the roll,
It was also confirmed that the hole bottom R having the same size can be shared. For example, 400x of the general Invert product series
In case of 100 series (web width x flange width), this series includes 3 sizes with different web thickness and flange thickness, but the minimum flange thickness is 16 mm,
The maximum thickness was 18 mm and the difference was 2 mm, and there was no particular problem even if the hole bottom R having the maximum flange thickness was set.

Further, since the flange forming rolling machine 20 of the present invention can change the left and right roll body widths arbitrarily, it is not necessary to change the rolls of the flange forming rolling machine 20 even if the web height of the channel steel changes. Absent. Also, by adopting the skew roll system, the intermediate universal rolling mill 2
Even if (21) and the horizontal roll cylinder width of the rough shaping rolling mill 3 (31) are worn, the insufficient width can be relieved by the widening action of the flange forming rolling mill 20 of the oblique roll type. That is, the life of the horizontal rolls of the intermediate universal rolling mill 2 (21) and the rough shaping rolling mill 3 (31) can be extended. Further, the upper and lower horizontal rolls 2 of the finishing universal rolling mill 21
Since the cylinder widths of 1a and 21b are also changeable, it is the same as in the case of the above flange forming and rolling mill that the roll change due to the size change is unnecessary.

By providing the horizontal rolls of the flange forming mill 20 and the finishing universal mill 21 so that the cylinder width can be changed, the following rolling method can be adopted to improve the rolling efficiency. is there. That is, in the reverse rolling process of the intermediate universal rolling, the length of the material to be rolled grows with each pass, but for example, the elongation length during the intermediate universal rolling is equal to that of the flange forming rolling machine and finishing universal rolling machine in the next stage. When there is interference, the flange forming and rolling mill reduces or enlarges the roll cylinder width to make an empty pass and retract it to a position where it does not interfere with the pass. According to this rolling method, since the unit weight of one rolled material can be increased, the production efficiency can be improved.

[0017]

INDUSTRIAL APPLICABILITY According to the present invention, in the production of channel steels, particularly channel steels for use in invert products, the shape of the tip of the flange is "bent out" or "sharp edge" as compared with the conventional universal rolling method. The occurrence of shape defects such as is eliminated, and since product series with different sizes can be shared by the same roll, the unit consumption of roll is greatly improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the layout of an inventive device array.

FIG. 2 is a schematic view showing a rolling sequence and a hole shape in the rolling method of the present invention.

FIG. 3 is a schematic plan view showing a rolling state using a skew type flange forming mill used in the rolling apparatus train of the present invention.

FIG. 4 is an enlarged view of a hole-shaped portion of the flange forming and rolling machine of the device row of the present invention.

FIG. 5 is a schematic diagram showing a layout of a conventional channel steel rolling mill train.

FIG. 6 is an explanatory view of a conventional channel steel rolling means.

FIG. 7 is a schematic cross-sectional view of an invert product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double rough rolling mill 2 Intermediate universal rolling mill 3 Rough shaping rolling mill 20 Flange forming rolling mill 21 Finishing universal rolling mill 20a Upper roll of flange forming rolling mill 20b Lower roll of flange shaping rolling mill 20c Recessed groove

Claims (3)

(57) [Claims] 1. A slab having a rectangular cross section or a roughly shaped steel slab is roughly shaped into a groove shaped roughly shaped material by a double roughing mill, and then subjected to a predetermined rolling by a reverse rolling between a rough shaping rolling mill and an intermediate universal rolling mill. After forming the groove-shaped intermediate material of web thickness and width, the flange tip of the groove-shaped intermediate material is formed into an arc shape with a double intermediate shaping mill capable of changing the roll cylinder width of the upper and lower rolls. A hot rolling method for channel steel, characterized in that finish rolling is carried out by a finish universal rolling machine having upper and lower horizontal rolls which can be changed. 2. A double rough rolling machine in which a plurality of rough shaping hole dies are engraved, an intermediate universal rolling machine and a rough shaping rolling machine which are arranged in close proximity to each other for continuous rolling, and a roll cylinder width is changed. A flanging and rolling machine in which a concave groove is engraved in one of the upper and lower rolls of the possible upper and lower rolls, and a stepped portion that presses the flange outer corner is formed in the other roll A hot rolling mill train for channel steel, characterized in that a finish universal rolling mill having rolls is arranged in order. 3. A pair of skew rolls whose axial cores of the upper and lower rolls of the flange forming mill can be adjusted within a plane horizontal to the rolling direction and at a predetermined angle θ _H with respect to a plane vertical to the rolling direction. The hot-rolling apparatus train for channel steel according to claim 2, wherein: