JPH1190506A - Checkered plate excellent in bending workability - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely suppress deviation at the time of bending to the degree without being hindered in practical use. SOLUTION: In the checkered plate provided with projections whose max. width is W, length is L, angle formed with the longitudinal direction in the rolling direction of the steel plate is α and pitch is P and projections whose max. width, length and pitch are the same and the angle formed with the longitudinal direction in the rolling direction of the steel plate is -α or α-90 alternately on the surface of the steel plate, the formula: 0.83<=(W+L)/(2<1/2> .P) is satisfied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a striped steel plate used as a floor plate of a construction site, a parking lot, a step plate of a stair, etc. for preventing slippage.

[0002]

2. Description of the Related Art A striped steel sheet is a steel sheet in which projections are formed continuously or discontinuously at a constant pitch on the surface of the steel sheet by hot rolling. It is used for such purposes.

FIG. 2 shows a projection pattern of a general striped steel plate described in Japanese Patent Application Laid-Open No. 6-81170. The protrusions in the figure have a height of 2 mm, a maximum width of 5.1 mm, and a length of 25.
The central part of 3 mm is in the shape of a bar with a bulging part, and a projection having an angle of 45 ° between the longitudinal direction and the rolling direction of the steel sheet and a projection of −45 ° are alternately provided on the steel sheet surface at a pitch of 28.6 mm regularly. ing.

[0004] In recent years, high added value of striped steel sheets has been pursued, and high processing accuracy has been required in bending and the like. However, since the thickness of the striped steel sheet is different between the portion where the protrusion is present and the portion where the protrusion is not present, when the bending process is performed, it does not bend at the position where it should be bent, which often causes a problem in the processing accuracy.

Japanese Patent Application Laid-Open No. Hei 7-51701 discloses that after forming projections with a grooved roll, flat rolls are used so that the heights of adjacent projections are equal when the steel sheet cross section is viewed from the rolling direction or the direction perpendicular to the rolling direction. A method of rolling to obtain high bending accuracy is disclosed.

[0006]

However, when the present inventors made a striped steel sheet by the method described in Japanese Patent Application Laid-Open No. Hei 7-51701 and performed bending work, the steel sheet did not bend at the position where it should be bent. Thus, there was a problem in practical use.

The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a striped steel sheet which can surely suppress a deviation at the time of bending to such an extent that it does not cause a practical problem.

[0008]

The object of the present invention is that the maximum width is W, the length is L, and the angle between the longitudinal direction and the steel sheet rolling direction is α.
A projection provided at a pitch P, the projection and the maximum width,
In a striped steel plate in which protrusions having the same length and pitch and forming an angle of -α or α-90 with the steel plate rolling direction in the longitudinal direction are provided alternately on the steel plate surface, the following formula (1) is satisfied. Solved by striped steel plate. 0.83 ≦ (W + L) / (2 ^1/2 · P) (1)

The present inventors have studied the bending workability of the striped steel plate and found that the deviation during bending is closely related to the maximum width W, length L and pitch P of the projections. Was. The details will be described below.

From a commercially available striped steel sheet and a striped steel sheet prepared by intentionally changing the shape and pitch of the projections, a 1-m test piece is sampled along the width direction of the steel sheet, and bent at right angles to the rolling direction. Was measured for the maximum deviation from the position where it should bend. In addition, a separate investigation has confirmed that there is no practical problem if the maximum deviation amount is within 5 mm.

FIG. 1 shows the relationship between the maximum deviation amount and (W + L) / (2
^{1/2 1} / 2P). If (W + L) / (2 ^1/2 · P) is set to 0.83 or more, the maximum deviation amount during bending is 5 m.
It can be seen that it can be suppressed within m. (W + L) / (2
^Although the upper limit of ^{1/2 上限} P) is not particularly defined, it is preferable that the upper limit is set to a range in which roll surface processing for transferring stripes to a steel sheet can be reliably performed, for example, 0.95 or less.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION It is preferable that the height of a projection is 1 mm or more from the viewpoint of preventing slippage.

The angle α between the longitudinal direction of the projection and the rolling direction of the steel sheet
Is not particularly defined, but when the angle is 45 °, projections are easily formed.

[0014]

EXAMPLE A slab of SS41 steel for a structure was hot-rolled by a finishing tandem rolling mill to produce a striped steel sheet having a ground thickness of 3.2 mm and a width of 920. At this time, grooved rolls of various shapes were installed on the final stand of the finishing mill, and the maximum width W, the length L, and the pitch P in the steel sheet width direction were changed as shown in Table 1, and the height was 1.7 mm. Projections were formed. Then, 10 test pieces of 1 m in length were sampled along the width direction of the steel sheet, and each of them was bent at an arbitrary position in a direction perpendicular to the rolling direction, and the maximum displacement was obtained as described above.
The occurrence rate in the case of exceeding mm was determined.

The results are shown in Table 1. It can be seen that if the relationship between the maximum width W, the length, and the pitch satisfies the range of the present invention, that is, the above expression (1), the occurrence rate when the maximum deviation exceeds 5 mm can be reliably reduced to zero.

[0016]

[Table 1]

[0017]

Since the present invention is configured as described above, it is possible to provide a striped steel sheet that can surely suppress the deviation during bending to such an extent that there is no practical problem.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a maximum deviation amount and (W + L) / (2 ^1/2 · P).

FIG. 2 is a view showing a projection pattern of a general striped steel sheet described in Japanese Patent Application Laid-Open No. 6-81170.

Continuation of front page (72) Inventor Manabu Nakatsugawa 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd.

Claims (1)

[Claims] A projection having a maximum width of W, a length of L, an angle of α with the rolling direction of the steel sheet in the longitudinal direction, and a projection provided at a pitch P, and having the same maximum width, length and pitch as the projection. In the striped steel plate in which the angle between the longitudinal steel plate rolling direction and the angle of -α or α-90 is alternately provided on the steel plate surface,
A striped steel sheet satisfying the following expression (1). 0.83 ≦ (W + L) / (2 ^1/2 · P) (1)