JPH0647401A - Dividing rolling method for steel bar - Google Patents

Abstract

PURPOSE:To equalize the cross-sectional area of each divided intermediate grooved steel bar. CONSTITUTION:After one rolled stock 1 which is heated at a prescribed temp. is formed into a multigrooved base stock 4 by equally cutting three or more notching grooves 3 toward the center of cross section with slit rollers, the base stock 4 for multiple bar is formed into three or more intermediate steel bars 9 by radiately dividing it at the center of cross section and each of intermediate steel bars 9 is made into the product 10 having a prescribed cross-sectional shape by finish rolling with grooved rolls.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip rolling method capable of simultaneously rolling at least three strips from one rolled material by splitting a strip such as a steel bar or a section steel.

[0002]

2. Description of the Related Art Conventionally, as a method of dividing and rolling this kind of steel strip, the two-row slit method shown in FIG.
Further, the 3-4 division method shown in FIGS. 4 (b)-(d) has been proposed, and some of them are being put into practical use. In the double-slit method shown in Fig. 4 (a), rolled material B heated to a predetermined temperature is
Rolled by a hole-shaped roll of a rolling mill, consisting of two strips of material that are connected to each other at one node from the rolled material B 1
A multi-strip material M of a book is formed, and this multi-strip material M is cut by a slit roll from the knot portion to form two intermediate-stripe steel materials.
IW is not used, and each intermediate steel strip IW is finish-rolled by a finishing rolling mill group to produce two steel strips (bar steels) W having a predetermined sectional shape.

FIG. 4 (b) shows one of the four-row division method,
Rolled material B is rolled with a hole-type roll, and one multi-threaded material M consisting of four materials that are connected to each other by three nodes
The material M is torn to form four intermediate bar steel products IW by ripping the nodes from the knots using a ripping roll, and each intermediate bar steel product IW is finished by a finishing rolling mill group (Japanese Patent Publication No. 62-2883). reference).

FIG. 4 (C) shows another example of the four-row division method, in which one multi-row material M composed of four articles is divided into two multi-row materials M1 and the middle of the two articles. The material M1 is divided into four intermediate steel strips IW, and each intermediate steel strip IW is finish-rolled (see, for example, Japanese Patent Publication No. 62-2882). Furthermore, Fig. 4 (d) shows that the rolled material B is formed into one multi-strand material M consisting of two strips of material, and this material M is divided into two intermediate strips M3 and shaped. This is a method in which M3 is formed into a multi-stripe material M4 composed of two strips of material, each material M4 is further divided to form an intermediate steel strip IW, and each intermediate steel strip IW is finish-rolled.

[0005]

By the way, the above two-row split rolling method can increase the production amount of small-diameter products without increasing the material speed and the number of rolling mills.
The four-division rolling method has the advantage that high productivity can be obtained. However, in each of the conventional division rolling methods described above, since the rolled material B is divided in the horizontal direction, the cross-sectional areas of the left, right, and center are not uniform, and the weight variation of the product easily occurs, and the adjustment is difficult. The problem was that it was very difficult. This is because it is difficult to set the intermediate strip steel material to be filled between the hole-shaped rolls in an appropriate amount because the rolling is performed by the hole-shaped rolls.

The present invention has been made in view of the above situation, and an object thereof is to make the sectional areas of three or more intermediate steel strips divided from one rolled material even. The purpose of the present invention is to provide a method of dividing and rolling a steel strip.

[0007]

In order to achieve the above object, the present invention takes the following technical means. That is, according to the present invention, one rolled material heated to a predetermined temperature is slit into three or more cut grooves toward the center of the cross section by a slit roller to form a multiple strip material, and then the multiple strip material is formed. It is characterized in that it is radially divided from the center of the cross section to form three or more intermediate bar steel machines, and each intermediate bar steel material is finish-rolled by a hole roll to obtain a product having a predetermined sectional shape.

[0008]

According to the present invention, a rolled material having a point-symmetrical cross section is cut by a group of blade rolls toward the center of the rolled material cross section.
A multi-row material formed by equally dividing the notch grooves
Since the blade is radially divided from the center of the cross section, the pressing force of the blade is directed toward the center of the material and the centering is automatically performed, so that the cross-sectional shape and the cross-sectional area of each of the three or more intermediate steel strips are equalized. Therefore, at the time of finish rolling with the grooved rolls, the intermediate section steel material is filled with the grooved section area without excess or deficiency, the section areas of the rolled products are the same, and the variation in weight is eliminated.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a cross-sectional view of a strip steel strip rolling process which is a first embodiment of the present invention, and FIG. 2 shows a schematic arrangement of slit roller groups in a material splitting process of the first embodiment. 1 is a rolled material, which has a square cross section that is a point-symmetrical cross section, is heated to a predetermined temperature by a heating furnace (not shown), is passed between a set of four slit rollers 2, and is equally divided toward the center of the rolled material 1 cross section. To 4
The deep groove 3 of the strip is formed over the entire length in the length direction, and becomes a single multi-strip material 4 having a cross-sectional shape similar to four petals having the same cross-sectional area.

At this time, the upper and lower slit rollers 2 automatically perform the upper and lower centering, and the left and right slit rollers 2 automatically perform the left and right centering, so that each slit roller 2 inevitably faces the center of the cross section. Be cut into. The groove 3 can be divided into a plurality of times to increase the depth thereof, as indicated by a dotted arrow in FIG. Next, one multi-stripe material 4 is passed between a pair of upper and lower slitting slit rollers 5 and divided into two material 6, and each material 6 is composed of a slit roller 7 and a flat roller 8. It is passed between the cleaving roller groups and divided into upper and lower parts, respectively, and finally, it is radially divided into four from the center of the cross section of the rolled material 1 to form an intermediate bar steel material 9 having the same cross-sectional area of four.

Each intermediate bar steel material 9 thus formed
Is a hole-type roll (not shown) in the same group of finish rolling mills as before.
4 round bar steel 10 having a predetermined shape is finished by a plurality of finish rollings. At this time, since the cross-sectional areas of the intermediate strip steel materials 9 are the same, each steel material 9 is evenly filled between the hole-shaped rolls without excess or deficiency, and each finished round steel bar 10 has the same cross-sectional area. The product has a cross-sectional shape and no variation in weight.

According to the first embodiment described above, since the cross-sectional shape of the rolled material 1 is a point-symmetrical square, the pressing force, that is, the cutting force of the slit roller 2 is directed to the center of the cross-section of the rolled material 1, so that the slit roller is The center of the rolled material 1 is automatically performed by the second group, and furthermore, there is no blurring when the rolled material is deformed by the slit roller 2, and the intermediate strip steel material 9 that is accurately divided into equal parts is obtained, and good quality is evenly distributed. Can be rolled into various products.

FIG. 3 shows a cross-sectional view of a second embodiment of the present invention, in particular, a process of dividing a rolled material into intermediate-strand steel materials. Rolled material 1 has a regular hexagonal cross-sectional shape, and is 3 toward the center of the cross section. The deep groove 3 of the strip is equally divided to form the multi-strip material 4,
By twisting 4 in a spiral shape, three intermediate steel strips 9 are formed. Each of the intermediate steel strips 9 thus formed has the same cross-sectional shape, and also has the same cross-sectional area and weight. Therefore, as in the first embodiment, by passing each intermediate steel strip 9 through the hole-type rolls of the finishing rolling mill group one or more times, it is possible to finish the steel strip with the same cross-sectional area without variation in weight.

The present invention is not limited to the above-mentioned embodiment, and for example, the cross-sectional shape of the rolled material may be a circle having a point symmetry, a regular polygonal shape, or the like. It can be rolled more than strips.

[0015]

As described above, according to the present invention, one rolling material heated to a predetermined temperature is divided into three or more notched grooves toward the center of the cross section by slit rollers to form a multi-row material. After forming, the multi-stripe material is radially divided from the center of the cross section to form three or more intermediate strip steel machines, and each intermediate strip steel product is finish-rolled by a hole-shaped roll to form a product with a predetermined cross-sectional shape. Therefore, it is possible to make the cross-sectional areas of the respective intermediate strip steels uniform, and to obtain a high-quality rolled product with no variation in weight with high productivity.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a process of division rolling showing a first embodiment of the present invention.

FIG. 2 is a schematic perspective view of a slit roller group in the material dividing step of the first embodiment.

FIG. 3 is a sectional view of the progress of division showing a second embodiment of the present invention.

4 (a) to 4 (d) are cross-sectional views of a conventional split rolling process.

[Explanation of symbols]

 1 Rolled material 2 Slit roller 3 Groove 4 Multi-strip material 5 Slit roller 7 Slit roller 9 Intermediate strip steel 10 Strip product

Claims (3)

[Claims] 1. A rolled material heated to a predetermined temperature,
After slitting three or more cut grooves equally toward the center of the cross section with a slit roller to form a multi-row material, the multi-row material is radially divided from the cross-section center to form three or more intermediate steel strips. A method for split rolling of a steel strip, characterized in that each intermediate steel strip is finish-rolled by a hole roll to obtain a product having a predetermined cross-sectional shape. 2. The method of split rolling of a steel strip according to claim 1, wherein the multi-stripe material is split by a slitting roll. 3. The split rolling method for a strip steel according to claim 1, wherein the multi-strip material is split at the same time by twisting.