JP2001340911A - Bending prevention equipment of steel strip plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent bending of a steel strip caused by leaping-up of a tip portion, without producing any scratches on the steel strip. SOLUTION: In a bending prevention equipment preventing bending that is caused by leaping-up of a tip portion of the steel strip 13 occurring on a run out table 12 of a fine hot finishing mill 11, the equipment is provided with a detection sensor 1 for a tip portion of the steel strip detecting the tip portion of the steel strip 13 arranged at the upstream side of the run out table 12, an on/off valve controller 4 controlling timing of opening an shutting of the on/off valve 3 arranged in a pipe 2 supplying injected water in which the injected water can prevent bending on the basis of a detection signal from the detection sensor 1 for the tip of the steel strip and an injection device 5 horizontally ejecting the injected water onto the lead-up tip of the steel strip 13 toward an advancing direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel strip for preventing a leading end portion of a steel strip going out of a hot finish rolling mill toward a winding machine from being bent on a run-out table behind the hot finish rolling mill. The present invention relates to a bending prevention device.

[0002]

2. Description of the Related Art A steel strip rolled to a predetermined thickness by a hot finish rolling mill is cooled by cooling devices provided on the upper and lower surfaces of the run-out table behind the hot finishing rolling mill. While being cooled to a predetermined temperature by the injected cooling water, it passes through a run-out table, reaches a winder, and is wound around a coil by the winder.

On the other hand, in a hot strip rolling line for a steel strip, rolling is performed at an extremely high rolling speed (referred to as a passing speed on a run-out table) in order to improve the rolling efficiency. If the passing speed on the run-out table is too fast, the steel strip moves forward while bounding on the run-out table due to low rigidity in the case of a thin steel strip (called waving). This phenomenon occurs.

[0004] Then, the end portion of the steel strip is a runout tee.
When the steel strip jumps up, the tip of the steel strip is bent due to the resistance force received from the cooling water, the impact force at the time of colliding with the side guide, and the like. When such a bend occurs, the tip of the steel strip cannot pass through the pinch roll provided in front of the winder, so that winding by the winder becomes impossible, or the vicinity of the pinch roll becomes impossible. There is a problem that the equipment is damaged.

[0005] Even if the tip of the steel strip can pass through the pinch roll, the tip of the steel strip is wound around a coil in a bent state. Must be cut out and shipped, which lowers the product yield.

A conventional method for preventing the steel strip from being bent at such a run-out table is disclosed in Japanese Unexamined Patent Publication No.
There is one disclosed in Japanese Patent No. 84617.

A method for preventing the occurrence of webbing of the steel strip is to cool a hot-finished rolled metal strip (steel strip) on a hot runtable (runout table). The cooling water from the side spray nozzle is injected before the metal strip is passed along the traveling direction.

Further, as an apparatus for preventing the occurrence of webbing of a steel strip, there is one disclosed in Japanese Patent Application Laid-Open No. Hei 10-118709. This device is a device for stabilizing the passing of hot-rolled steel sheets on a run-out table of a hot-rolling finishing mill,
At least at least upstream of the run-out table, in which the velocity component in the traveling direction of the hot-rolled steel sheet injecting water onto the upper surface of the hot-rolled steel sheet (steel strip) is equal to or higher than the speed of the hot-rolled steel sheet. And a control device for controlling the operation of each spray device, the control device comprising:
The spraying device has a calculating means for calculating the injection start and injection stop timings of the apparatus, and an operation control means for controlling the injection start and injection stop operations of each spray device with reference to the calculation results by the calculating means.

[0009]

However, there are the following problems in the above-mentioned conventional technology for preventing the waving generated at the tip portion of the steel strip. (1) Method disclosed in Japanese Patent Application Laid-Open No. 4-84617 The waving is generated not only at the end of the steel strip but also at the middle part of the steel strip due to a slight peripheral speed difference between the table rollers. May be. Therefore, in the method of preventing the waving of the steel strip by the cooling water at all times, when the waving is generated in the middle part of the steel strip and the loop-shaped part is generated in the steel strip, it is forcibly looped. In order to flatten the peaks and valleys on the ridges and valleys of the loop of the steel strip,
A quality defect occurs in which the part is bent.

(2) Method using the apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 10-118709 Since water is jetted from above, the tip of the steel strip is
There is a possibility that it will get stuck between the la and it will not be able to pass through. Further, if the injection start timing is shifted, a defect similar to the above (1) occurs in the middle part of the steel strip.
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a steel strip bending prevention device that does not cause the occurrence of quality defects or the inability to pass a sheet. .

[0011]

SUMMARY OF THE INVENTION An apparatus for preventing bending of a steel strip according to the present invention is an apparatus for preventing bending of a steel strip tip caused on a run-out table of a hot finish rolling mill due to a jump of a tip of the steel strip. A steel strip tip detection sensor provided at the upstream side of the steel strip for detecting the tip of the steel strip, and an on-off valve provided on a pipe for supplying jet water for preventing bending based on a detection signal from the steel strip tip detection sensor. An opening / closing valve controller for controlling the opening / closing timing of the steel strip, and an injection device for injecting the jetted water horizontally into the jumping tip of the steel strip in the traveling direction.

In the apparatus for preventing bending of a steel strip according to the present invention, a tip detecting sensor detects a front end of the steel strip upstream of the run-out table, and supplies jet water for preventing bending based on the detection signal. Since the opening and closing timing of the on-off valve provided in the pipe is controlled, it is possible to inject jet water for preventing bending only in a required range at the end of the steel strip.

Therefore, even if a loop-shaped portion is generated in the middle portion of the steel strip, the steel strip is not pressed by the force of the jet water, so that no quality defect is generated in the middle portion of the steel strip.

[0014] Further, since the spray water for preventing bending is sprayed horizontally in the traveling direction of the steel strip, in the case of a steel strip whose tip does not jump up, the spray water is sprayed onto the steel strip at the tip. Does not hit the steel strip, so that the end of the steel strip does not penetrate between the adjacent table rollers, and the sheet cannot be passed.

[0015]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of a steel strip bending preventing device according to the present invention, in which (a) is a plan view of the steel band bending preventing device, and (b) is a side view of the steel band bending preventing device.

This steel strip bending preventing device is a device provided for preventing bending caused by a jump of a steel strip tip generated on a run-out table 12 of a hot finishing mill 11 and a run-out table. A steel strip tip detection sensor 1 that is provided upstream of the steel strip 12 and detects the tip of the steel strip 13, and a pipe 2 that supplies jet water that prevents bend based on a detection signal from the steel strip tip detection sensor 1. An on-off valve controller 4 for controlling the opening / closing timing of the on-off valve 3 provided; and an injection nozzle 5 for horizontally injecting the jetted water to the jumping tip of the steel strip 13 in the traveling direction of the steel strip 13. Two are provided. In the drawing, reference numeral 14a denotes an upper steel strip cooling device, and 14b denotes a lower steel strip cooling device.

Using this steel strip bending prevention device,
The method of preventing bending of the steel strip tip will be described as follows.

When the tip of the steel strip 13 is detected by the steel strip tip detection sensor 1, the detection signal is sent to the on-off valve controller 4. The on-off valve controller 4 issues a valve opening command to the on-off valve 3 based on the detection signal. With this command, the on-off valve 3 is opened, and the injection water for preventing bending is sent to the injection nozzle 5 through the pipe 2.

Then, from the injection nozzle 5, the injection water is injected horizontally toward the forward end of the steel strip 13 in the traveling direction of the steel strip 13, thereby preventing the steel strip 13 from bending. When the injection is performed for a predetermined time, the on-off valve 3 is closed by the timer. Therefore, since the spray water for preventing the bending is sprayed only at a part of the tip of the steel strip 13, even if a loop-shaped portion is generated in the middle part of the steel strip 13, the spray water is injected into the steel strip 13. Therefore, no quality defect occurs in the middle portion of the steel strip 13 because the steel strip 13 is not pressed down.

Further, the injection water for preventing bending is supplied to the steel strip 1.
3, the steel strip 13 is jetted horizontally in the direction of travel of the steel strip 13 so that the tip of the steel strip penetrates between the adjacent table rollers due to the water pressure of the jet water, and cannot be passed. It does not become.

It is preferable that the jet direction of the jet water is inclined at a range of 5 degrees or more and less than 30 degrees with respect to the traveling direction of the steel strip 13. This is because even if spray water is sprayed from both sides in the width direction of the steel strip at less than 5 degrees, the spray water may hit only one side of the tip of the steel strip that has jumped up. Because it may be bent in a direction perpendicular to the traveling direction of the object.

On the other hand, if the angle is 30 degrees or more, the force of the water jet in the width direction of the steel strip hitting the tip of the steel strip that has jumped up increases, and the tip of the steel strip that jumps up in the same direction as the steel strip travels. This is because there is a risk of being bent in a direction perpendicular to the direction.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to confirm the effect of the above-described device for preventing bending of a steel strip according to the present invention, the discharge pressure of jet water was set at 5.88MPa.
The test was performed as a.

As a result, it was found that, out of the 20 steel strips that were about to jump, bending could be prevented up to 19 (95%), and the effect of the present invention was great.

[0025]

According to the present invention, only bending of the steel strip tip can be prevented, so that the product yield does not decrease.
In addition, a situation in which threading cannot be performed does not occur.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of a steel strip bending preventing device according to the present invention, in which (a) is a plan view of the steel band bending preventing device, and (b) is a side view of the steel band bending preventing device. .

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel strip tip detection sensor 2 Piping 3 On-off valve 4 On-off valve controller 5 Injection nozzle 11 Hot finishing rolling mill 12 Run-out table 13 Steel strip 14a Upper steel strip cooling device 14b Lower steel strip cooling device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenji Shimizu 1-1-2 Marunouchi, Chiyoda-ku, Tokyo, Japan Inside Nihon Kokan Co., Ltd. (72) Inventor Takaharu Nambu 1-2-1, Marunouchi, Chiyoda-ku, Tokyo, Japan Inside the Kokan Co., Ltd. (72) Shigeo Tsuchiya, Inventor 1-1-2 Marunouchi, Chiyoda-ku, Tokyo, Japan Inside the Kokan Co., Ltd. (72) Inventor Ikuo Takenami 1-2-1, Marunouchi, Chiyoda-ku, Tokyo, Japan Honko Tube Co., Ltd.

Claims (1)

[Claims] Claims 1. A device for preventing bending of a steel strip tip generated on a run-out table of a hot finish rolling mill due to a jump of the steel strip tip, wherein the steel strip tip provided upstream of the run-out table is provided. A steel strip tip detection sensor to detect, an on-off valve controller for controlling the opening / closing timing of an on-off valve provided in a pipe for supplying jetting water for preventing bending based on a detection signal from the steel strip tip detection sensor,
An apparatus for preventing the steel strip from being bent, wherein an injection device for horizontally injecting the sprayed water in the traveling direction to the jumped tip of the steel strip is provided.