JPS60240309A - Method for marking and rolling steel sheet having irregular section - Google Patents

Abstract

PURPOSE:To eliminate the need from measuring the thickness of the cross sectional shape of a strip having an irregular section formed by a continuous hot rolling mill and to permit easy matching of a shearing position in rolling of said strip by putting a reference roll mark for shearing to the rolling material by the work roll of the final stand. CONSTITUTION:A recessed or projecting ring indicating the shearing position of the rolling material is attached to the final upper roll or lower roll or upper and lower rolls for rolling irregular section of the continuous hot rolling mill. The need for measuring and checking the thickness of the shearing part is eliminated even if the rolling material has an inconvenience such as meandering. The matching of the shearing position is thus made easy by viewing the transferred projecting or recessed part, by which the working efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method of rolling a steel strip (hereinafter referred to as irregular cross-section strip) having thickness differences in the width direction.

(Prior art) The irregular cross-section strip having a difference in plate thickness in the strip width direction according to the present invention can be used to reduce the use of steel plates triggered by the energy crisis in recent years, or to reduce manufacturing costs and energy consumption due to the proliferation of structures and vehicles. There is a strong interest in achieving reductions in stress and, furthermore, application of steel plates having thickness differences according to stress levels in order to actively improve rigidity. For such application members, a hot strip mill rolls them into one or multiple strips depending on the cross-sectional shape, and then performs edge cutting or slitting in the next step.

Conventionally, as seen in Japanese Patent Publication No. 3'7-667, in order to accurately shear the required cross-sectional shape when performing edge cutting or slitting in the next process of irregular cross-sectional strips rolled with a hot strip mill. In addition, at the start of shearing the coil, the thickness of the cross-sectional shape is recognized by measurement, positioning is performed, and edge cutting or rinsing is performed.

However, when rolling in a hot strip mill,
It is extremely difficult to avoid meandering of the strip due to any change in rolling conditions VC, and the cross-sectional shape is not always constant in the longitudinal direction of the coil. In addition, the old method of measuring the thickness has problems with measurement accuracy, and the measurement itself is troublesome.

(Problems to be Solved by the Invention) The present invention has been devised against the background of the above circumstances, and it provides a method for effectively and economically detecting the shear position of an irregular cross-section strip of an IJ tube. A rolling method is provided.

(Means for Solving the Problems) The present invention is a method of rolling a strip of irregular cross-section, characterized in that marks corresponding to shearing positions are provided on the strip of irregular cross-section on a work roll of a hot strip mill. That is, the present invention provides a method for rolling irregular cross-sectional strips in a single stand or multi-stage stand in a hot strip mill, by applying -Cvs to the work roll of the final stand forming the rolled material as a shearing standard when shearing the positively rolled material. This will give you a roll mark. Therefore, the appropriate position of the work roll on the final stand can be changed into convex, concave, or
In addition, the shape is such that it leaves marks different from other parts on the rolled material during rolling.

The present invention also applies to the shapes of these work rolls when the shape is applied to the upper work roll alone, the lower work roll alone, or to the upper and lower work rolls.

Next, further explanation will be given using figures.

FIG. 1 is an explanatory diagram showing the form of an irregularly shaped IJ tube formed by the method of the present invention. tg is the maximum plate thickness, tl is the minimum plate thickness, and 1 is the roll mark that serves as the reference line during shearing.
2 is the shear position.

FIG. 2 is an explanatory diagram showing the form of a work roll of a final stand for forming a steel plate with a modified cross section.

3 is a roll recess for providing a roll mark to be used as a shear reference for the irregular cross-section strike IJ tube.

The roll recess 3 is not limited to this, and may be a convex shape or may have another shape.

This work roll is assembled into the final stand, a strip of irregular cross section is rolled, and a roll mark 1, which serves as a reference line during shearing as shown in Fig. 1, is added.This reference line is detected during shearing in the next process and By doing so, it becomes possible to shear a strip with a modified cross-section having a good cross-sectional shape.

(Effects of the Invention) When shearing irregular cross-section strips using the method of the present invention, there is no need to take the trouble of measuring the thickness, and the time for shearing and positioning can be significantly shortened, making it an extremely effective invention industrially.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the form of a rolled material obtained by the method of the present invention. FIG. 2 shows the configuration of a work roll for carrying out the method of the invention and forming into irregular cross-section strips in a hot strip mill. l...Roll mark that serves as a reference for the shear plane, 2.
...Shear position, 3...Roll dent. Agent: Patent attorney Masamitsu Akizawa and 2 others/

Claims (1)

[Claims] (1) When rolling irregular cross-sectional strips with different thicknesses in the width direction using a continuous hot rolling mill, the work rolls of the final stand that form the rolled material make roll marks that serve as shearing standards when shearing the rolled material. 1. A method of rolling a strip of irregular cross-section, the method comprising: