JPH0191926A - Method for spreading width of slab by forging - Google Patents

Abstract

PURPOSE:To drastically increase the width spreading of the material of a thin thickness without any trouble by forging dy forming a tool shape so that the contact of a material and tool is started from one part in the material width direction and its position is gradually changed in the material with direction. CONSTITUTION:In various tool shapes such a tool shape that a forging start begins from the one part in the material width direction and its deformation is gradually transferred to the other parts as shown in the figure, for instance, is used. The metal subjected to rolling reduction is thus easy to flow in the width direction rather than the longitudinal direction and the width is increased. At the time when forging is executed by using this tool 4, a material 3 receives a compression by the tool 4, the tool tip part only compresses one part in the with direction of the material and the width spreading is started with the metal being flowed in the width direction. Even if the material progresses in order only one part in the width direction receives the compression on any section, width spreading is caused and the whole compression in the material width direction is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a method for increasing the width of slabs of various materials by forging.

(Prior art) At present, most of the hot strip materials used as steel products are continuously cast materials, and are generally rolled from slabs of several widths in the hot strip rolling process. As seen in the publication, mainly by width reduction using vertical rolls.

By reducing the width by 0 to 300 square meters, many desired product widths are manufactured.

This is because, in the continuous casting process, manufacturing slabs with different widths depending on the width of each product would result in excessive mold costs and would not be an economical manufacturing method.

(Problems to be Solved by the Invention) Currently, the casting thickness of continuous casting is generally 200 to 100 am+m, but it is expected that the thickness will gradually become thinner in the future, for example, to 40 am. In such cases, the ratio of slab thickness to plate width is too large;
Since buckling of the slab easily occurs due to reduction, the width reduction method described above cannot be applied. The present invention was made to adjust the width of thin-walled materials.

The present invention was made in order to solve the above-mentioned conventional problems, and an object of the present invention is to provide a method that can realize the widening of a slab without any trouble by forging.

(Means for Solving the Problems) The present invention is characterized in that in a method for reducing the thickness of a slab material by forging, the tool shape is such that the contact between the material and the tool starts from a part of the width direction of the material. The objective is to create a shape in which the position gradually changes in the width direction of the material, thereby reducing the wall thickness of the slab and increasing #2.

The present invention will be explained in detail below. First of all, it is empirically known that when forging is performed using a normal tool 1 as shown in FIG. 3, the width of the slab 2 only increases by a few steps of reduction at most. Through many experiments, the inventors found that
We have discovered a tool shape that dramatically increases width expansion.

That is, as shown in Fig. 1, in various tool shapes,
If you use a tool shape that starts forging or deforms one part of the material in the width direction and gradually transfers to other parts, the rolled metal will flow more easily in the width direction than in the longitudinal direction, increasing the width. I found out what to do.

FIG. 4 shows the deformation process when forging using tool a shown in FIG. 1. The material 3 is compressed by the tool 4, and first, facing A to 8, only the tip of the tool or a part of the width of l[l is compressed, and the metal flows in the width direction. Start expanding the width. Even if the material progresses sequentially,
In any cross-section, only a part of the material is compressed in the width direction, and the width expands, and then through the B to B cross sections, and the C to C cross sections, the compression in the entire width direction of the material is completed.

The shape of the tool is not necessarily a straight line, but may be an arc, or the smaller the angle α, the easier the width will be. The shape of the tool is selected depending on the desired width as shown in FIG. 1 (a), (b), and (c), which shape is good in principle. If the contact surface is large, the forging load will also be large, so this must also be taken into consideration.

FIG. 2 shows the relationship between the hole angle α and the width expansion ratio. From this figure, you can select an appropriate tool size and obtain the desired width. Figure 2 shows wall thickness: 40III11° width;
IQOOmm hot work steel is used with the tool shown in No. 11A, α-3
The width expansion ratio (width after forging/width before forging) when forged to 34 mm is shown.

In addition, in order to obtain a desired product width by forging from a material with a constant width, it is also possible to use tools with different tool shapes, or f
! It is easier to adjust the amount of reduction in the construction. In Figure 5, under the same conditions as Figure 2, using a tool with α = 60°,
The width expansion ratio is shown when the rolling reduction amount is changed to 16 ram. Since the width expansion ratio is approximately proportional to the amount of reduction, the width expansion ratio can be adjusted from 1.0 to 1.4 by arbitrarily selecting the amount of reduction. When the width expansion ratio is small, that is, when the reduction amount is small, the wall thickness after forging will naturally become thicker,
- In order to obtain a product with a certain wall thickness, it is necessary to take into account in advance the capacity of the rolling mill, etc., whether the burden of rolling in the post-dividing process will be large.

Note that the application of the present invention is not limited to steel materials, but also to non-ferrous materials, plastic materials, etc., when the width is increased by forging using the above-mentioned tool.
Please note that it is included. In addition, it may be applied immediately after the continuous casting process, it may be applied to the rough stage of the rolling process, or it may be applied alone. Furthermore, it can be applied hot or cold.

(Example) A steel slab with a wall thickness of 40 m+t+ and a width of 1000 m+n was hot forged to 34 mm using a tool with α=60 degrees as shown in FIG. 1, resulting in a width of 1400 mm.

(Effects of the Invention) According to the present invention, the width of the slab can be significantly increased by forging, and the width of the element H can be changed freely.

[BRIEF DESCRIPTION OF THE DRAWINGS] Figures 1 (a), (b) and (c) are perspective views showing examples of the shape of the forging tool used in the method of the present invention, and Figure 2 is a perspective view showing an example of the shape of a forging tool used in the method of the present invention.
Graph showing the relationship between the single-hole type angle and the width expansion ratio, Figure 3 (
a) (b) is an explanatory diagram showing the forging process of the Congregation Song Dynasty, Figure 4 (
a) (b) (c) (d) is a bottom explanatory view (a) showing the deformation process in the present invention, and its A-A, B-B, C-
The sectional view C and FIG. 5 are graphs showing the relationship between the amount of pressure F and the width expansion ratio. 1.4...Tools, 2.3...Materials. IQIB Castle=-14! -m- 1% pze drawing and (a) Ji=-ichiza Σ2Y Kotsu engraving (b') A-A CC) B-day (cL) C-C Procedural judgment 11 official book (method) Showa January 20, 63

Claims (1)

[Claims] In a method of reducing the wall thickness of a slab material by forging, the tool shape is formed such that the contact between the material and the tool starts from a part of the width direction of the material, and the position gradually changes in the width direction of the material, A method for widening a slab by forging, the method comprising reducing the wall thickness of the slab and increasing the width.