JPS5930482B2 - Steel rolling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for hot rolling steel materials, and its purpose is to prevent the generation of temperature differences between the upper and lower sides by rolling the steel materials upside down during rolling. The aim is to eliminate the curvature of direction.

Conventionally, when H-beam steel is manufactured continuously by reverse rolling, for example, the material is rolled with its vertical position unchanged.

Therefore, in the rolling mill, the roll cooling water W is poured only onto the upper surface of the steel material, and cooling is performed on the upper surface of the steel material.

As a result, as shown in the temperature distribution (SD) in Figure 5, H
The temperature of the upper and lower sides of the section steel is higher than that of the upper side (
As a result, deformation occurs during cooling, causing bending in the longitudinal direction of the material or making it impossible to obtain the desired cross-sectional shape.

Furthermore, since rolling of H-section steel is three-dimensional rolling, the accuracy of predicting the flange width is poor (accurate rolling control is difficult).

In other words, Nakagami-bias S Let O be It is difficult to

If center deviation occurs, it increases as the number of passes increases, resulting in defective products.

This invention has been proposed to address the above-mentioned conventional problems.

Next, the embodiments of this invention will be described with reference to the drawings.
The figure shows an overview of the H-beam rolling process, with a heating furnace (not shown)
The heated material is descaled, then rough rolled by a breakdown mill 1, then rolled by a rough universal mill 2, and finally finished shaped by a finishing universal mill 3.

In the present invention, a steel material reversing device 4 is provided at the entrance and exit of the rolling mill 20, and the vertical position of the steel material is reversed.

As shown in FIGS. 2 to 4, the reversing device 4 is formed with guide blocks 4 bl , 4 b2.4 b3 projecting above a main body 4 a.

The upper parts of the guide blocks 4b1, 4b2, and 4b3 have a high cant slope on one side, and the slope becomes steeper as the distance from the rolling mills 1 and 2 increases.

That is, as shown in FIG. 4, the angle α1°α2.
α3 becomes α1 × α2<α3.

5 is a conveyor roll, and 6 is a side guide.

In this way, after exiting the rolling mill, the H-beam 7 advances to the reversing device 4, where it is guided by the slopes of the guide blocks 4b1, 4b2, and 4b3, gradually twisting and changing its inclination, and finally ends up in the H-beam 7.
The shape steel 7 is turned upside down.

Then, for reversing, the vehicle is similarly reversed at the exit.

Since the vertical position of the steel material is reversed in this way, cooling is performed evenly in the vertical direction.As a result, as shown at SD in Fig. 5, the temperature distribution in the vertical direction becomes uniform, there is no deformation in the cross section of the product, and the longitudinal direction There will be no bending.

Furthermore, the center deviation does not increase due to an increase in the number of passes.

Note that it is not necessary to perform the above inversion for all paths.

Therefore, the reversing device 4 is supported by a lifting means 8 and raised when necessary.

As described above, according to the present invention, since the steel material is inverted when manufacturing a steel material, for example, an H-beam, it is possible to prevent the deformation of the cross section of the product and the occurrence of bending in the longitudinal direction, and to prevent the center of the web from being biased. Able to manufacture good products.

[Brief explanation of drawings]

Fig. 1 is a plan view showing an overview of the manufacturing process, Fig. 2 is a front view of the reversing device, Fig. 3 is a cross-sectional view along the line ■-■, and Fig. 4 is a plan view showing an overview of the manufacturing process.
The figure is a perspective view, and FIG. 5 is an explanatory diagram showing the temperature distribution of the H-section steel. 1...Breakdown rolling mill, 2...
Roughing universal rolling mill, 3... Finishing universal rolling mill, 4... Reversing device, 4a...
・Main body, 4b1, 4b2+4b3...Guide block, 5...Transport roll, 6...Side guide, 7...H-shaped steel, 8... ... Lifting means, α1. α2. α3...Angle between the top surface of the guide block and the horizontal line.

Claims (1)

[Claims] 1. A method of rolling a steel material, characterized in that rolling is performed by reversing the top and bottom of the steel material during hot rolling by a rolling mill between a - pass and the next pass.