JPH0734922B2 - Strip width reduction method - Google Patents

Description

The present invention relates to a strip width reduction method performed between stands of a finish rolling mill.

[Prior Art] Conventionally, the width reduction of a rolled material is generally performed by an edger provided near the rough rolling machine on the upstream side of the rolling line. However, if the width reduction is performed on the upstream side of the rolling line, the thickness reduction performed on the downstream side of the rolling line causes edge drops at the material edges and the strip cross-sectional shape deteriorates. There has been a problem that the error of the obtained plate width increases and the plate width accuracy decreases. Therefore, in recent years, it has been studied to perform width reduction between finishing stands on the downstream side of the rolling line to improve the cross-sectional shape and width accuracy of the strip.

[Problems to be Solved by the Invention] However, when the edger is provided between the finishing stands to perform the width reduction, the strip becomes thinner due to the thickness reduction on the upstream side. Buckling may occur.

The present invention has been made in view of the above circumstances, and an object thereof is to enable width reduction of a thin object without buckling.

[Means for Solving the Problems] The present invention has been made to solve the above technical problem, and when performing width reduction of the strip between the finishing mill stands, the slip upper surface is removed between the roll gaps of the edger rolls. A width reducing method for a strip, characterized in that the strip is pressed down by an upper press roll, and the upstream side of the strip is raised by a looper roll to hold the winding angle of the strip with respect to the upper press roll while reducing the width. is there.

[Operation] Therefore, in the present invention, in the vicinity of the roll gap of the edger roll, the strip is wound around the upper pressing roll at a required winding angle to perform width reduction.
By the winding angle and the tension, the apparent rigidity of the strip can be increased, and the width reduction can be performed while suppressing the occurrence of buckling.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show an example of an apparatus for carrying out the method of the present invention, in which edger rolls 4 and 5 are pressed against both width ends of a strip 3 between rolling mill stands 1 and 2 for finish rolling. An edger 6 for reducing the width of the strip 3 is provided.

An upper pressing roll 7 for pressing the upper surface of the strip 3 is provided in a gap between the edger rolls 4 and 5 of the edger 6 and further between the upper pressing roll 7 and the upstream side rolling mill stand 1. A looper roll 9 is provided which pushes the strip 9 upward by rotating the arm 8.

The looper roll 9 can adjust the looper angle θ by ascending by an adjustment drive device 10 that rotates the arm 8.

In the above, when the looper angle θ is increased by the adjustment drive device 10 and the looper roll 9 is raised, the strip 3 is pushed up, and thus the strip 3 is wound around the upper presser roll 7 at the required winding angle α. It will be.

In this way, by giving the winding angle α, the apparent rigidity of the strip 3 is increased in combination with the tension of the strip 3, so that the strip 3 buckles even when the edger 6 performs width reduction. Therefore, it becomes possible to perform edging with a thin material, improve the plate width accuracy, and improve the edge drop.

FIG. 3 shows the relationship between the winding angle α and the limit width reduction force at which the strip 3 buckles, and the buckling is caused by increasing the looper angle θ and increasing the winding angle α. It is obvious that it will not occur.

Incidentally, the present invention is not limited to the above-mentioned embodiment, and the method of raising the looper roll can be arbitrarily selected, and various changes can be made without departing from the scope of the present invention. Is.

[Advantages of the Invention] As described above, according to the strip width reduction method of the present invention, the strip upper surface is pressed by the presser rolls between the roll gaps of the edger rolls that perform the width reduction between the finish rolling mill stands, and Since the strip upstream side is lifted by the looper roll to wind the strip around the upper pressing roll at a required winding angle and to reduce the width, the apparent rigidity of the strip is increased by the tension of the strip and the winding angle. It is possible to prevent the occurrence of bending, and therefore, it is possible to achieve an excellent effect of enabling edging of a thin object, improving plate width accuracy, and improving edge drop.

[Brief description of drawings]

FIG. 1 is a side view showing an outline of an example of an apparatus for carrying out the method of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a looper angle and a limit of width reduction force causing buckling. It is a graph which shows the relationship of. 1, 2 is a rolling mill stand, 3 is a strip, 4 and 5 are edger rolls, 6 is an edger, 7 is an upper pressing roll, 8 is an arm, 9 is a looper roll, 10 is an adjusting drive device, θ is a looper angle, α indicates a winding angle.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Nobu Nagakura No. 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Ishi, Kawashima Harima Heavy Industries, Ltd. Yokohama No. 2 Factory (72) Toshio Yamamoto Shin, Isogo-ku, Yokohama-shi, Kanagawa Nakaharacho No. 1 Ishikawajima Harima Heavy Industries Co., Ltd. Yokohama No. 2 Factory (72) Inventor Satoshi Matoba 5-3 Tokaicho, Tokai-shi, Aichi Pref.Nippon Steel & Steel Co., Ltd. Nagoya Works (72) Inventor Yayoi Igarashi 5-3 Tokai-cho, Tokai-shi, Aichi Pref. Nippon Steel Co., Ltd. Nagoya Steel Works (56) Reference JP 59-70403 (JP, A) JP 58-86902 (JP, A) JP Sho 59-183904 (JP, A)

Claims (1)

[Claims] 1. When performing strip width reduction between stands of a finish rolling mill, the upper surface of the strip is pressed by an upper pressing roll between the roll gaps of the edger rolls, and the upstream side of the strip is raised by a looper roll. A width reduction method for a strip, which is characterized in that width reduction is performed while maintaining a winding angle of the strip with respect to a press roll.