JPH05154503A - Manufacture of small size stainless shape steel - Google Patents

Abstract

PURPOSE:To improve the productivity of a shape steel by conducting electric power and heating the drawing-out raw material to a specific temp., hot-rolling into a hoop material having spread width of the shape steel and forming a projecting line at one side and successively, continuing a bending process and a finish-rolling process with forming rolls. CONSTITUTION:A wire rod wound in coil-shape is used to the raw material 12 and this raw material is drawn out and heated to 900-1100 deg.C by conducting the electric power. The raw material 12 is hot-rolled into the hoop material 24 having spread width of the shape steel and forming the projecting line at the one side on the bent line. The hoop material 24 is bent at a prescribed angle in the bent line while forming the projecting line to the outside with the forming roll 26 and successively, the process for finish-rolling the bent material is continued. By this method, the wire rod wound in the coil-shape is used as the raw material, the weight of the raw material is increased, and the rolling yield and productivity are improved. Further, as the shape steel is continuously manufactured by form-rolling the hoop material, on which the projecting line is formed by with a strong pressure working, with the forming roll, the excellent productivity is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a small stainless steel (for example, equilateral angle steel having a width of 35 mm or less).
Manufacturing method.

[0002]

2. Description of the Related Art In the rolling of small and medium-sized steel, surface reduction rolling is followed by modeling rolling. Make exactly. Generally, the rough angle is rolled by a rough roll into a square or a rectangular shape.

Forming rolling is started from a rough angle, and a 4-9 roll is formed by cutting a die (caliber) according to various products between upper and lower rolls and sequentially passing between these die according to the arrangement. The product is finished with a pass.

The method of manufacturing a small-sized stainless steel, for example, an equilateral angle steel having a width of 35 mm or less is of course the same as the above-mentioned method, but stainless steel has a large deformation resistance and a small cross-sectional dimension. The temperature drop is large, so the dimensions of the material are 50 mm square and 800 mm long.
The weight is about 40 kg, and a relatively small weight material is used.

[0005]

However, according to the conventional method, since the material is rolled into a square cross section in the area-reduction rolling, it is difficult to balance the amount of reduction between the upper and lower hole-shaped rolls during shaping rolling. Therefore, there is a drawback that it is not possible to carry out strong reduction, the number of passes increases, and the equipment becomes large.

[0006] Further, in rolling small stainless steel, the rolling resistance is large and the cross section is small, so that the temperature drop is large and only a small weight material can be used, so that the rolling yield is low and the productivity is low. There is a problem. For example,
When manufacturing 25 × 25 × 3 mm helix angle steel such as stainless steel, the rolling yield is at most about 90% because there are many cutoffs at both ends, and the productivity is only the rolling process, and the labor cost per ton is 3.3. Man-made / ton.

The present invention has been made in view of the above-mentioned problems in the method for producing a small stainless steel, and it is possible to use a large weight material, the rolling yield is high, and continuous automation is possible. As a result, it is an object of the present invention to provide a method for producing a small stainless steel having excellent productivity.

[0008]

Means for Solving the Problems The inventor has conceived to use a coil of a wire rod having a circular cross section as a material in view of the necessity of increasing the weight of the material and the relationship with the rolling balance during shaping and rolling. We have made extensive studies on a method that enables continuous shaping and rolling using these materials. As a result, it was found that the material drawn from the coil is electrically heated, and immediately hot-rolled into a strip having a ridge formed on one side, which is subjected to strong pressure processing, whereby the subsequent forming and finish rolling steps can be continued. The present invention has been completed.

The method for producing a stainless small shaped steel of the present invention comprises a step of using a wire rod wound in a coil shape as a raw material, pulling out the raw material, and electrically heating it to 900 to 1100 ° C. Having a step of hot rolling to a strip having a ridge formed on one side on the fold line, and a step of bending the strip at a predetermined angle on the fold line with the ridge outward by a forming roll, The gist is that the process of finishing and rolling the bent material is continued.

The size of the wire used as the material is not so large because it is heated by electricity.
It is about mmφ. The withdrawal from the coil is performed by a pinch roll that also serves to correct the material. The electric heating of the material is performed by, for example, bringing electrode rolls into contact with each other at a predetermined interval and energizing them.

As the forming roll, a conventionally known hole type roll is used, and is bent at a desired angle in 3 to 4 passes. The amount of reduction in finish rolling is 0.1 to 0.5 mm, which may be warm or cold. When rolling channel steel, a universal rolling machine or a turks head in which two sets of rolls are combined at right angles is used in finish rolling.

[0012]

In the method of the present invention, since the wire wound in the coil shape is used as the material, the material weight becomes about 1000 kg,
Compared with the conventional billet of about 40 kg, the material becomes heavier and the rolling yield and productivity are significantly improved. Since the drawn material is heated to 900 to 1100 ° C. by electric heating, it is heated to a rolling temperature at which hot rolling can be performed.

In the step of hot-rolling the material into a strip material having the expanded width of the shaped steel and having a ridge formed on one side on the bending line, the cross-section of the material is circular, so that 1
It can be processed into a strip material having a width of the expanded shape of the shaped steel in the pass and a ridge formed on one side on the folding line.

This strip is shaped and rolled into a shaped steel having a desired shape by a step of bending the strip at a predetermined angle along the bending line with the convex strip on the outside by a forming roll. Then, the bent material is finished and rolled into a desired shape and dimension. The above steps are all performed continuously, and the material is processed in a state where it is pulled out from the coil and connected to finish rolling, so that it can be made continuous and automated.

The heating temperature of the material to be energized is set to 900 to 11
The reason why the temperature is set to 00 ° C. is that if the temperature is lower than 900 ° C., the deformation resistance is large and the desired high pressure processing cannot be performed.
If it exceeds the range, the scale is often generated and cracks are likely to occur during processing.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of a rolling apparatus for carrying out the method of the present invention. Material 1 from the coil 10 which wound the wire rod
2 is pulled out by the pinch roll 14 which also serves as a straightener.

The material 12 pulled out by the pinch rolls 14 is caught by two pairs of electrode rolls 16 and 16 which are arranged at a constant interval. A power source 18 is connected between the two pairs of electrode rolls 16 and the material 12 is 900 to 1100 while passing through the electrode roll 16.
It is electrically heated to ℃.

The material 12 that has passed through the electrode roll 16 is 9
It is heated to 00 to 1100 ° C., and then hot rolled by the hot rolling roll 20. Hot rolling roll 2
No. 0 is provided with a hole shape, and the rolled material 12 is rolled into a strip material 24 having a developed width of a shaped steel and having a ridge 22 formed on one side on the bending line, as shown in FIG. It

Subsequently, the strip 24 is formed by the forming roll 2
6 is bent at a predetermined angle on the bending line with the ridge 22 on the outside.
Is composed of three rolls, and the band 24 is bent by the first roll 26a at the angle shown in FIG. 3A, and then further bent by the second roll 26b at the angle shown in FIG. 3B. By the third roll 26c, FIG.
It is bent at 90 ° as shown in. 7 is a sectional view taken along the line AA of FIG.

The bending material 28 bent by the forming roll 26 is further subjected to finish rolling by the finish rolling roll 30, adjusted to a desired size and shape, and cut by the shearing 32 into a predetermined fixed length.

Using the rolling apparatus of the present embodiment, using an austenitic stainless steel 24 mm round bar as a material, 25 ×
When 25 × 3.5 mm angle steel was rolled, the rolling yield was 96%, the productivity was 1.5 man / ton,
It was confirmed that the rolling yield was improved by 6% and the productivity was improved by about 2 times as compared with the conventional method.

Although the angle steel is manufactured in this embodiment, when the channel steel is manufactured, the bending line is 2
Therefore, the strip material 24 rolled by the hot rolling roller forms two ridges 22 as shown in FIG.
Then, in the shaping rolling by the forming roller 26,
Forming is completed by sequentially bending as shown in FIGS. 5A and 5B and finally combining a pair of horizontal rollers 34 and a pair of vertical rollers 36 as shown in FIG.

[0023]

As described in detail above, the method for producing a stainless small shaped steel of the present invention uses a wire rod or a round bar wound in a coil shape as a raw material, and after the electric heating, the raw material has a spread width of the shaped steel. It is hot-rolled into a strip having a ridge formed on one side of the fold line, and the strip is bent at a predetermined angle on the fold line with the ridge on the outside with a forming roll, and finish rolling is performed. Since the wire material wound in a coil shape is used as the material, the material becomes heavy and the rolling yield and the productivity are remarkably improved. Also, since the material has a circular cross section, it can be processed by high pressure processing into a strip material with a width of the expanded width of the shaped steel in one pass and a ridge formed on one side on the bending line. By model rolling,
Since the shaped steel can be continuously manufactured, the productivity is remarkably excellent.

[Brief description of drawings]

FIG. 1 is a side view of a rolling apparatus used for carrying out the method of the present invention from electric heating to finish rolling.

FIG. 2 is a cross-sectional view of an angle steel strip.

3 (a), (b) and (c) are cross-sectional views showing a process of forming and rolling a bent material of angle steel.

FIG. 4 is a cross-sectional view of a channel steel strip.

5 (a) and 5 (b) are cross-sectional views showing a process of shaping and rolling a bent material of channel steel.

FIG. 6 is a partial side view showing a finish rolling state of channel steel.

7 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

10 coil 12 material 16 electrode roll 20 hot rolling roll 22 convex strip 24 strip material 26 forming roll 28 bending material 30 finishing rolling roll 32 shearing

Claims (1)

[Claims] 1. A process in which a wire wound in a coil shape is used as a raw material, and the raw material is drawn out and electrically heated to 900 to 1100 ° C., and the raw material has a spread width of a shaped steel and a ridge is formed on one side of a bending line. A step of hot-rolling the formed strip material, a step of bending the strip material to a predetermined angle on the bending line with the ridges outside by a forming roll,
A method for producing a small stainless steel, comprising a step of finishing rolling the bent material.