JP3518236B2 - Rolling method for section steel - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates <br/> rolling how shape steel, especially steel sheet piles, Mizokatachiko rolling direction of shape steel containing 1 part of bending processes of a cross section of such Angle iron about the law.

[0002]

2. Description of the Related Art Conventionally, in the rolling of a shaped steel sheet such as a sheet pile, a double or triple reversing rolling mill provided with a plurality of hole dies is used to combine the lateral transfer of materials and to form the holes. The method of rolling the mold back and forth has been adopted. For example, as shown in FIG. 6, a steel sheet pile is reciprocally rolled with a rolling material reheated in a heating furnace in a hole type of a breakdown mill B, a rolling mill S and a rolling mill F, and further, if necessary. It is rolled by the final finishing mill FF and finished into a sectional shape as shown in FIG.

However, in this rolling method, the number of passes is large, and it takes time to transfer the material in the lateral direction between the hole dies in the same rolling mill and to transfer it between different rolling mills, so that the rolling efficiency is lowered and the material is rolled. There was a problem that the temperature drop of the above became large. Further, there is a method of continuously arranging a large number of rolling mills provided with only one hole type and continuously rolling in one pass. This rolling method has no lateral material transfer,
Since it is continuous rolling in one direction, the rolling efficiency is extremely high, but since it uses a large number of rolling mills, it requires a long installation site and a large amount of capital investment. If the reduction setting and the speed setting are not performed optimally, too much tension will be applied, resulting in deterioration of the product's shape and dimension. Conversely, if the tension is too small, it will receive excessive compression and form a loop between stands. Therefore, in the case of shaped steel having a complicated cross-sectional shape, it is necessary to control the rolling reduction and the speed setting with particularly high accuracy. Further, there are many problems such as having to prepare a large number of hole type rolls.

To solve the above problem, for example, Japanese Patent Laid-Open No. 52-11
In Japanese Patent No. 4463, two double reversing rolling mills having a plurality of hole types are arranged in close proximity to each other, and rolling material is continuously rolled between these two rolling mills and lateral material movement is performed. A method of rolling a steel sheet pile is disclosed in which a rolling speed difference between two rolling mills is set to 1 to 8% during reciprocal rolling. According to this technique, the number of passes is reduced and the rolling efficiency is improved even with a small number of rolling mills. However, since a rolling speed difference is made between the two rolling mills, a speed control device is required, tension is applied to the material, and a slight variation in rolling speed causes a large variation in the dimensions of the joint in the longitudinal direction of the product. There is a problem that it easily occurs. Furthermore, in order to prevent the material from bending and biting into the hole mold, it is necessary to install a lateral movement device for transferring the entire length of the material in parallel on both the front surface and the rear surface when introducing the material into the next hole mold. Yes, the longer the material, the greater the investment required to install it before and after the rolling mill.

[0005]

[0008] The present invention is to solve the problems described above, and an object thereof to propose an inexpensive rolling how small section steel having longitudinal dimensional variations of products.

[0006]

SUMMARY OF THE INVENTION The present invention is a method for rolling a shaped steel using a hole rolling mill, in which two hole rolling mills having a plurality of hole types are arranged in proximity to each other with their hole types facing each other. Place and
On the outbound route, only one of the two rolls is rolled, and on the return route, the
A rolling method of a shaped steel, characterized in that a reciprocating rolling step of rolling only on the other side of the base is performed at least once, and in the present invention, after the reciprocating rolling step, the rolled material is moved in the lateral direction, Alternatively, at least one reciprocal rolling process in which the sets of different hole types are similar to the above-described reciprocal rolling process, in which the rolling process is different on the forward pass and the backward pass, and the lateral movement of the rolled material is at least 1.
After repeating this process, at least one of the hole types may be subjected to bending and rolling.

Further, in the present invention, after carrying out the rolling for bending forming, the rolling for further bending forming may be carried out by a hole rolling mill different from the two hole rolling mills .

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, in a rolling mill for a shaped steel consisting of a plurality of group rolling mills, a group of rolling mills in which two group rolling mills each having a plurality of group rolling are closely arranged. . The two hole rolling mills are arranged close to each other so that the respective hole types face each other and the rolled material can go straight and pass in a skewer shape.

First, the rolled material is rolled by a breakdown mill or the like. Then, the rolled material is rolled by a rolling mill group consisting of two hole rolling mills, or further rolled by another hole rolling mill to obtain a finished shaped shaped steel. In the rolling in this rolling mill group, the rolled material is subjected to reciprocal rolling in which the rolled material goes straight and passes through the holes of the two rolling mills in a skewer shape. In that case, only one of the two rolling mills is rolled on the outward path, and then only the other of the two rolling mills is rolled on the return path. Such a reciprocal rolling process is performed at least once. It goes without saying that the number of times of this reciprocal rolling process can be appropriately changed according to the product to be rolled.

In this reciprocal rolling, since only one of the two hole types is rolled, no tension is generated in the rolled material during rolling. Therefore, it is not necessary to adjust the rolling speed between the two rolling mills with high accuracy. Further, in the present invention, after the reciprocal rolling process is performed, the rolled material is laterally moved by the lateral movement device installed only on one side of the front or rear of the rolling mill, and rolling is performed in the following hole type. As a result, the number of lateral movements of the rolled material can be reduced, and the installation of the lateral movement device
Only one of the front side and the rear side of the rolling mill group is required, which makes it possible to reduce capital investment.

FIG. 1 shows, as an example of the present invention, a flow of a rolled material in rolling when two group rolling mills S1 and S2 are arranged close to each other. a to f indicate a hole type. In this case, a horizontal moving device for rolling material is installed in front of the hole rolling mill S1 (upward in the drawing). In the hole rolling mill S1,
The a, c, and e hole types are transferred to the hole rolling mill S2 by b, d, and f.
The holes are arranged so that a and b, c and d, and e and f face each other so that the rolled material can advance straight in a skewer shape. Among them, the hole die f is bending forming rolling of the joint portion in the case of a steel sheet pile. After the rolling material is subjected to the reciprocal rolling process with the cavities a and b, the rolled material is transferred in the lateral direction, and then the reciprocal rolling is performed with the cavities c and d. In these reciprocal rollings, rolling is performed only in one of the different hole types in the forward and return passes. For example, when using the hole forms a and b and rolling only with the hole form a on the outward path, the hole form a is set to a roll gap for rolling the rolled material, and the hole form b is set up and down so as not to roll the rolled material. The roll material is opened by passing the roll gap.

On the other hand, on the return path, rolling is performed only in the hole die b, and in the hole die a, the roll material is set so as not to roll the rolled material, the rolled material is passed, and the rolled material is returned to the front surface of the rolling mill S1. Hole type a,
Following the rolling in b, the rolled material is moved in the lateral direction, then reciprocally rolled in the cavities c and d, returned to the front surface of the rolling mill S1 again, and then laterally transferred to the cavities e and f. It is continuously rolled at and sent to the rear of the rolling mill. The order of reduction in reciprocal rolling with the hole types a and b and the order of reciprocal rolling with the hole types c and d may be exchanged. For example, the outward pass may be rolled in the hole type b, and the outward pass may be rolled in the hole type a. In the hole types e and f, rolling is continuously performed in both hole types of the two rolling mills. The hole shape f or the hole shapes e and f is for bending the joint portion in the case of a steel sheet pile. The change in the cross-sectional area of the joint portion hardly accompanies the change in the cross-sectional area of the entire material. Therefore, even if some unbalance occurs in the rolling speed between the die dies e and f, it is absorbed by the slip between the die dies f and the material, and the cross-sectional dimension of the material is hardly affected. The rolling in the hole type f can be applied even if it is not the bending forming rolling as long as it is a rolling that hardly changes the cross-sectional area of the material.

Needless to say, the number of hole dies provided in the closely arranged rolling mills may be appropriately changed according to the product to be rolled. FIG. 2 (a) shows the flow of the material when rolling the steel sheet pile by arranging two roll mills S1 and S2 having two rolls on one roll in close proximity.
Further, FIG. 2 (b) shows a material flow in two group rolling mills S1 and S2 in which four rolls are provided on one roll.

Further, as shown in FIG. 3, after performing reciprocal rolling with a rolling mill R such as a breakdown mill, a hole rolling mill S is used.
In addition to the reciprocal rolling in which two S1s and S2s are arranged close to each other and rolling is performed by different rolling mills on the outward path and the returning path, and continuous rolling is performed in a row of rows of die including a die to be bent, and if necessary, a roll mill S
A rolling method may be adopted in which a hole rolling mill is arranged on the downstream side of 1, S2 and one pass of bending rolling by the final finishing rolling mill FF is added.

In the arrangement of the rolling mills shown in FIG. 3, the breakdown mill for rolling H-shaped steel is the rolling mill R, the universal mill is the hole rolling mill S1, the edger mill is the hole rolling mill S2, and the finishing universal mill. By using the final finishing rolling mill FF, the rolling method of the present invention can be carried out by diverting the existing H-shaped steel rolling equipment.

[0016]

[Example] As a rolled material, thickness: 400 mm, width: 560 mm
The U-shaped steel sheet pile was rolled using the continuous casting bloom of No. 2 and the flow of the hole die and the rolled material shown in FIG. A breakdown mill B having three hole dies, a group of rolling machines S1 and S2 having two hole dies each having three hole dies, and a final finishing mill FF are sequentially arranged. ing. A moving table for rolled material is provided on the front surface of the rolling mill group (upward in the drawing). No moving table is installed on the rear surface.

The breakdown mill B has a box hole type
11 and two rough-molding holes 12 and 13 are installed. The rolling material reheated to 1250 ° C. in the heating furnace is rolled in a box hole die 11 for four passes to a rectangular cross section having a predetermined width and thickness, and then is reciprocally rolled in a plurality of passes in rough shaping die dies 12, 13. Then, the rolled material is sent to the hole rolling mills S1 and S2. In the hole rolling mills S1 and S2, the hole forms 14, 16 and 18 provided in S1
However, it is arranged so as to face the hole molds 15, 17, and 19 provided in S2 so that the rolled material can be directly fed in a skewer shape. In the first pass, the rolled material sent was rolled only by the die 14 of the die rolling mill S1, and the die 15 of the die rolling mill S2 opened the roll gap and did not perform reduction. In the return pass of the second pass, the material was rolled by the hole die 15 of the hole rolling mill S2, the roll gap of the hole die 14 of S1 was opened, and the rolled material was passed through.

Similarly, the rolled material was rolled only in the S1 hole die 16 in the third pass and in the S2 hole die 17 in the fourth pass. On the fifth pass, continuous rolling was performed with the S1 hole die 18 and the S2 hole die 19. The hole type 18 is a hole type for finally rolling the joint part of the steel sheet pile.
No. 19 was a hole type in which the joint part was bent halfway, and no defect in shape occurred even after continuous rolling. Since the joint part is not rolled down, the cross-sectional area of the entire material hardly changes before and after the rolling of the hole die 19.

After the rolling of the second pass and the fourth pass is completed, the rolled material is moved so as to be rolled in the next hole type by the material moving device installed on the front surface of the hole rolling mill S1, and the third pass is performed. The fifth pass was rolled. The rolled material in which the joint part is bent halfway in the hole rolling mill S2 is used as the final finishing rolling mill F.
It is sent to F, the final bending of the joint part is performed with the hole die 20, and U
Shaped sheet pile.

On the other hand, as a conventional example, a U-shaped steel sheet pile having the same size as that of the embodiment was rolled by the flow of the rolled material shown in FIG. 7 using the hole die shown in FIG. The size of the continuous casting bloom used, its reheating temperature, the rolling conditions in the breakdown mill B and the rolling conditions in the final finish rolling mill FF are the same as those in the example, and in the hole rolling mills S1 and S2. Only the rolling method is different from that of the example. That is, in the first pass, after continuously rolling with the hole type 14 of the groove type rolling mill S1 and the hole type 15 of the S2 type, it is moved in the lateral direction, and the hole type of the hole type rolling mill S2 is moved in the second pass.
After continuous rolling with 16 and S1 hole type 17, it is moved in the lateral direction, and in the third pass, it is continuously rolled with hole type 18 of S1 and hole type 19 of S2. . Rolling was performed while controlling the rolling speeds of the two hole rolling mills S1 and S2.

Comparing the embodiment of the present invention with the conventional example, the present invention does not require a speed control device, and only one lateral moving device is required as compared with the conventional example, which requires two.
U-type steel sheet pile can be manufactured with inexpensive equipment. Further, the variation in the width dimension in the longitudinal direction of the U-shaped steel sheet pile manufactured by the method of the present invention was ± 1 mm, which is the same as that of the conventional example.

In the embodiment, the final bending was carried out by the hole die 20 of the final finishing rolling mill FF, but as shown in FIG. 8, the hole mills 11, 12, 13, 14 were installed on the breakdown mill B. Needless to say, the final finish rolling mill FF is not necessary if the hole-type rolling mills S1 are provided with the hole-type rolling mills 15, 17, and 19 and the hole-rolling mill S2 is equipped with the hole-type rolling mills 16, 18, and 20. . The rolling method of the present invention is not limited to the production of U-shaped or straight-shaped steel sheet piles by bending forming of the joint portion of steel sheet piles, but also the groove shape having a rolling process such as bending forming without change in cross-sectional area in finish rolling. It goes without saying that it can also be applied to the manufacture of various shaped steels such as steel and angle steel.

[0023]

According to the present invention, there is no need to introduce a speed control device with high precision, and the material lateral transfer device can be provided only on one side before and after the rolling mill. A special effect in the industry is obtained in that it can manufacture shaped steel with high dimensional accuracy with little variation in product dimension in the direction.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a flow of rolled material showing an example of the present invention.

FIG. 2 is an explanatory diagram showing a flow of rolled material showing an example of the present invention.

FIG. 3 is an explanatory diagram showing a flow of rolled material showing an example of the present invention.

FIG. 4 is an explanatory diagram showing flows of a hole die and a rolled material.

FIG. 5 is a sectional view showing an example of a U-shaped steel sheet pile.

FIG. 6 is an explanatory diagram showing a flow of materials in a conventional steel sheet pile rolling method.

FIG. 7 is an explanatory diagram showing a material flow in a conventional method for rolling a steel sheet pile.

FIG. 8 is an explanatory diagram showing a flow of rolled material in another example of the present invention.

[Explanation of symbols]

1 web 2 flange 3 joints 11 ~ 20 hole type a to f hole type B Breakdown Mill F rolling machine H heating furnace R rolling mill S rolling machine S1, S2 hole rolling mill FF final finishing mill

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21B 1/00-11/00 B21B 27/02 B21B 39/00

Claims (3)

(57) [Claims] 1. A method for rolling a shaped steel using a hole rolling mill, wherein two hole rolling mills having a plurality of hole types are arranged in proximity to each other so that the two hole types face each other. A rolling method for a shaped steel, characterized in that the reciprocal rolling process of rolling only on one side and rolling on the other side of the two groups on the return path is performed at least once. 2. A reciprocal rolling in which the rolled material is laterally moved after the reciprocal rolling process, or further, only one of the different types of forward and backward passes, similar to the reciprocal rolling process, is performed in a group of different hole types. 2. The method for rolling a shaped steel according to claim 1, wherein the rolling and the lateral movement of the rolled material are repeated at least once, and then the bending is performed with at least one of the hole shapes. 3. After the rolling for bending forming,
3. A rolling mill other than the two rolling mills is used for further bending and rolling.
The method for rolling the shaped steel described.