JPH11314111A - Device for preventing meandering of hot-rolled steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent the meandering even in case of changing the kind of steel or the size of a rolling steel plate by jetting high pressure water from spray nozzles to the both side edge parts of the the hot-rolled steel plate. SOLUTION: A hot-rolled steel plate S is conveyed on a run-out table 1 in the advancing direction A of the hot-rolled steel plate. High pressure water 9 is jetted to the both side edge parts of the hot-rolled steel plate S from the spray nozzle pairs 6, 6' fitted to frame table 8, 8'. The pressure and/or the flow rate of the high pressure water 9 and changed according to the thickness and/or the width of the hot-rolled steel plate S. The jetting direction of the high pressure water 9 from the spray nozzle pairs 6, 6' can be the direction in which the force pushing the hot-rolled steel plate S to the direction of the center position 10 of the run-out table generates. The jetting direction of the high pressure water 9 is desirable to be inclined to the advancing direction A of the hot-rolled steel plate. The distances from the tip parts of the spray nozzles 6, 6' to the hot-rolled steel plate S are desirable to be constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing meandering of a hot-rolled steel sheet, and more particularly, it is generated while a hot-rolled steel sheet coming out of a hot-rolling finishing mill is conveyed on a run-out table to a winding machine. This is a device for preventing meandering of a hot-rolled steel sheet.

[0002]

2. Description of the Related Art A hot-rolled steel sheet is produced by continuously rolling a thick steel slab having a weight of 20 tons to reduce the thickness thereof, forming a steel strip having a predetermined thickness and width, and winding it into a coil. Products. At this time, the hot-rolled steel sheet after finish rolling has a length of 1,000
Since it reaches 0 m, it is transported at high speed on the run-out table to the winder.

[0003] By the way, such a hot-rolled steel sheet has various shapes at the tip, and no tension acts on the hot-rolled steel sheet until the tip is wound around the winder. Often meandering without. Therefore, a run-out table is usually provided with a mechanical side guide to correct the meandering of the hot-rolled steel sheet so that the tip of the hot-rolled steel sheet is wound around the winder in a correct posture. Also,
When the tail end of the hot-rolled steel sheet passes through the finishing mill, the tension of the hot-rolled steel sheet may be lost and the tail end may meander. Has been done.

[0004] However, the meandering correction by the mechanical side guide has a problem that the side end portion of the hot-rolled steel sheet is damaged. Particularly, in the case of a thin hot-rolled steel sheet, the frequency of occurrence of damage is high.

On the other hand, in a hot-rolled steel sheet production line, various steel types and sizes (thickness and width) are rolled, so that steel strips of various sizes run on a run-out table. That is, a thick material (usually, a plate thickness of 4 mm or more), a thin material (a plate thickness of about 1 to 2 mm), a wide width (1,5
00mm width), narrow (900mm width) steel strip runs,
It is necessary to prevent meandering with the same device.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention can reliably prevent meandering even if the steel type and size of a steel strip to be hot-finished rolled are changed or even in the same steel strip. An object of the present invention is to provide a meandering prevention device for a hot-rolled steel sheet.

[0007]

Means for Solving the Problems In order to achieve the above object, the present inventors have made intensive efforts to find a means that can be replaced with a mechanical side guide, and have conceived the use of high-pressure water. And this idea was embodied as the present invention.

[0008] That is, the present invention relates to a device for preventing meandering of a hot-rolled steel sheet provided on an outlet run-out table of a hot finishing rolling mill, wherein a spray nozzle for jetting high-pressure water to both side ends of the hot-rolled steel sheet. A meandering prevention device for a hot-rolled steel sheet comprising a pair.

In the present invention, high-pressure water is ejected from both ends of the hot-rolled steel sheet from the pair of spray nozzles to press the hot-rolled steel sheet in the direction of the center line of the run-out table. Meandering prevention can be achieved without damaging the side end of the hot-rolled steel sheet due to mechanical contact.

Further, the present invention is characterized in that the pressure and / or flow rate of the high-pressure water injected from the spray nozzle pair can be changed according to the thickness and / or width of the hot-rolled steel sheet. In this case, a plurality of pairs of spray nozzles having different pressures and / or flow rates of high-pressure water to be jetted may be provided, and an appropriate pair of spray nozzles may be selected according to a change in the thickness and / or width of the hot-rolled steel sheet. . When the thickness of hot-rolled steel sheet is changed widely from thin to thick, or narrow to wide, the high-pressure water with a constant pressure and a constant flow rate is only jetted to both ends of the hot-rolled steel sheet. This is because it is difficult to properly prevent meandering. For example, when high-pressure water at a pressure and a flow rate suitable for preventing meandering of a thick material is jetted to a thin material, the high-pressure water has a large energy, and therefore the meandering of the thin material is promoted. When high-pressure water at a flow rate is jetted onto a thick material, it is difficult to sufficiently prevent meandering because the energy of the high-pressure water is small. Therefore, a plurality of spray nozzle pairs having different pressures and / or flow rates of high-pressure water to be jetted are prepared in advance, and an appropriate spray nozzle to be used is used according to the thickness of the hot-rolled steel sheet traveling on the run-out table. By selecting a pair, good meandering prevention can be achieved without causing flaws in hot-rolled steel sheets from thin to thick. The pressure and flow rate of the high-pressure water to be ejected can be adjusted by setting the spray nozzle pair as a pair and making the pressure of the high-pressure pump variable, or by providing a flow control valve in the pipe from the high-pressure pump to the spray nozzle. It may be adjusted.

According to the present invention, the pressure and / or flow rate of the high-pressure water is adjusted in accordance with the thickness and / or width of the hot-rolled steel sheet. Meandering can be reliably prevented without generating a flaw. In this case, it is preferable to provide a plate thickness detector, a plate width detector, and a plate passage detector upstream of the meandering prevention device. This is because the adjustment of the pressure and / or the flow rate of the high-pressure water and the timing of the change can be surely grasped. Therefore, according to the present invention, not only when the size of the steel strip is changed, but also the meandering of the same steel strip due to a change in the thickness or the width of the steel strip can be dynamically prevented.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a meandering preventing device according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a run-out table provided between a finishing mill (not shown) and a winder (not shown), and is composed of a plurality of table rollers 2. These table rollers 2 are rotationally driven by a motor 3 via a speed reducer 4.

The hot-rolled steel sheet S that has exited the finishing mill is conveyed on the run-out table 1 in the direction of arrow A and taken up by a winder. At this time, the hot-rolled steel sheet S travels on the run-out table 1 without tension until the tip of the steel sheet S is wound around the winder. However, the tip of the hot-rolled steel sheet S often bends without going straight, and therefore, conventionally, a mechanical side guide is installed so as to sandwich the hot-rolled steel sheet S in the width direction. The central axis of the steel strip S was set at the central position 10 of the run-out table 1. Further, when the tail end of the hot-rolled steel sheet S passes through the finish rolling mill, the tension of the hot-rolled steel sheet S is lost, and the tail end may meander. A meandering correction was also made. However, since the side guide is in mechanical contact with the hot-rolled steel sheet S, a flaw often occurs on the end face in the width direction of the hot-rolled steel sheet S.

Therefore, in the present invention, instead of this mechanical side guide, as shown in FIG. 1, high-pressure water 9 that can prevent meandering without contacting a hot rolled steel sheet S with a mechanical member is used. It is decided. Reference numeral 5 in FIG. 1 denotes a meandering prevention apparatus according to the present embodiment, in which a pair of spray nozzles 6, 6 'are attached to mounts 8, 8', and a hot-rolled steel sheet S conveyed on a run-out table 1 in the direction of arrow A. It is configured such that high-pressure water 9 can be jetted to both side ends of the. In addition,
Piping and valves for high-pressure water are omitted.

For example, when a hot-rolled steel sheet S having a thickness of 2.0 mm or less passes, the high-pressure water 9 is sprayed from the spray nozzle pair 6, 6 'to both ends of the leading end or the tail end. To prevent meandering, on the other hand, for example, when the plate thickness is changed to 2.0 mm or more, or when changed, the pressure and / or flow rate of the high-pressure water 9 is increased, and
Meandering of the hot-rolled steel sheet S is prevented.

Here, the jet direction of the high-pressure water 9 from the spray nozzle pairs 6, 6 'may be any direction as long as a force for pushing the hot-rolled steel sheet S toward the center position 10 of the run-out table 1 is generated. But it is good. However, as shown in FIG. 1, it is more preferable to incline in the transport direction A of the hot-rolled steel sheet S. The distance from the tip of the nozzle to the hot-rolled steel sheet is preferably constant, and the nozzles 6, 6 'are provided with a known means (for example, a cylinder) that can freely advance and retreat in the axial direction. Is good. In addition, the jet direction of the high-pressure water 9 does not need to directly hit the end face of the steel sheet, but may be jetted from diagonally above the hot-rolled steel sheet S toward the end of the steel sheet as shown in FIG.

Next, the injection / stop of the high-pressure water 9 will be described.

Whether the hot-rolled steel sheet S traveling on the run-out table 1 is thick, thin, narrow, or wide is measured by a thickness detector or a width detector. The timing of passing through the installation position of the nozzle pair is predicted from the traveling speed of the steel sheet S, or a steel sheet passage detector is installed and detected on the exit side of the finishing mill. Then, as shown in FIG. 2, this signal is transmitted from the process computer 7 attached to the hot rolling equipment to the automatic valve 11 provided in the piping of each of the spray nozzle pairs 6, 6 ', and the fluctuation of the plate thickness and the like is performed. ,
The opening of the automatic valve 11 is adjusted such that the high-pressure water 9 having an appropriate pressure or flow rate is injected from the nozzle pair 6, 6 'according to the change. The same applies to the tail end. If the tension of the steel sheet S is wound around the winder and the tension is established, the high-pressure water 9
May be stopped. As for the tail end, after the tail end passes through the installation position of the spray nozzle pair 6, 6 ', the injection of the high-pressure water 9 is stopped.

In FIG. 1, two pairs of spray nozzles 6,
6 'is arranged, but may be a pair, and conversely, 3'
You may make it spray finely more than a pair.
Further, only the pressure of the high-pressure water 9 may be different between the respective spray nozzle pairs 6, 6 ', or only the flow rate may be different, and further, both the pressure and the flow rate may be different. Is also good.

In addition, according to the present invention, the high-pressure water 9 jetted according to the size of the hot-rolled steel sheet S is controlled so that the meandering caused by the temporal variation of the sheet thickness and the sheet width can be dynamically controlled.
The pressure or flow rate, or both, was adjusted, but the present invention is not limited to this, and when the change in plate thickness and plate width is large, a plurality of spray nozzle pairs with different specifications are arranged and appropriately Spray nozzle pair 6 with various specifications
6 'may be selected and switched for use.

[0022]

(Example 1) Using the meandering prevention device 5 having the two pairs of spray nozzles 6, 6 'shown in FIG. 1, the meandering state and flaw occurrence state of the hot-rolled steel sheet S were investigated.

First, when a hot-rolled steel sheet S having a thickness of 1.5 mm travels on the run-out table 1, the pressure of the high-pressure water 9 sprayed from the spray nozzle pairs 6, 6 'is increased by 10%.
The operation was carried out at a flow rate of 100 liters / min with kg / cm ² . Next, since the thickness was changed to the hot-rolled steel sheet S having a thickness of 2.5 mm, the ejection pressure of the high-pressure water 9 was changed to 20 kg / cm ² , and the flow rate was changed to 200 l / min. Further, as shown in FIG. 3, the high-pressure water 9 from the spray nozzle pairs 6, 6 'is jetted to the end face of the steel sheet S, and is inclined by 30 degrees in the running direction A of the steel sheet S. . Further, in order to confirm the effect of the present invention, the same investigation was conducted for the case where the meandering prevention device 5 was not used.

FIG. 4 shows the occurrence of meandering in such an operation. It is clear from FIG. 4 that the meandering prevention device 5 of the present invention can reliably prevent meandering. At that time, no flaw was observed at the side end of the steel strip in any case. (Example 2) Using a meandering prevention device 5 having three pairs of spray nozzles 6, 6 ', the meandering state and the flaw occurrence state of the hot-rolled steel sheet S were investigated.

First, a plate thickness of 1.5 mm and a plate width of 900 mm
When the hot-rolled steel sheet S travels on the run-out table 1, the high-pressure water 9 sprayed from the spray nozzle pairs 6, 6 '
Was operated at a jet pressure of 10 kg / cm ² and a flow rate of 100 l / min. Next, since the sheet thickness was changed to a hot-rolled steel sheet S having the same thickness and a width of 1500 mm, high-pressure water 9
Was changed to 20 kg / cm ² and the flow rate was changed to 200 l / min. The spray direction of the high-pressure water 9 from the spray nozzle pairs 6, 6 'is the same as in the first embodiment. Further, in order to confirm the effect of the present invention, the same investigation was conducted for the case where the meandering prevention device 5 was not used.

FIG. 5 shows a meandering situation in such an operation.
You. 5 that the meandering prevention device 5 of the present invention is used.
It is clear that meandering can be reliably prevented. That
In any case, in any case, a flaw is found on the side end of the steel strip.
Not observed. (Example 3) Having three pairs of spray nozzles 6, 6 '
Using the meandering prevention device 5, the process of hot-rolled steel sheet S in the same steel strip
Temporal meandering was prevented. Hot rolled steel strip S used
Has a thickness of 1.5 mm and a width of 900 mm.
When the hot-rolled steel sheet S travels on the run-out table 1,
Plate thickness detector, plate width detector, and plate passage detector installed upstream
The output unit always catches such information and responds to that information
Pressure and high pressure water 9 of the spray nozzle pair 6, 6 '
And flow rate were adjusted each time. Meandering was visually observed
However, there is no meandering from the front end to the rear end of the hot-rolled steel sheet S.
It was able to run smoothly and the winding was smooth. The first
The set value is set to 10 kg / cm ^Two, The flow rate
The flow rate was 100 liter / min. Also in this case, steel
No flaw was observed at the side end of the band.

[0027]

As described above, according to the present invention, meandering can be prevented without causing flaws, regardless of the size of the hot-rolled steel sheet exiting from the hot finishing mill. Also, if necessary, it is possible to prevent the meandering of the same steel strip dynamically.

As a result, in particular, the finish rolling of a thin-walled hot-rolled steel sheet can be stably performed, and the yield and productivity of the hot-rolled steel sheet can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a plan view showing an outline of a meandering prevention device according to the present invention.

FIG. 2 is a diagram illustrating a spray nozzle of the meandering prevention device according to the present invention.

FIG. 3 is a schematic diagram showing a state of jetting high-pressure water in the meandering prevention device according to the present invention.

FIG. 4 is a diagram showing the effect of the meandering prevention device according to the present invention.

FIG. 5 is a view showing another effect of the meandering prevention device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Run-out table 2 Table roller 3 Motor 4 Reduction gear 5 Meandering prevention device 6, 6 'Spray nozzle pair 7 Process computer 8, 8' Mount 9 High-pressure water 10 Center line of run-out table 11 Automatic valve A Direction of hot-rolled steel sheet S Hot rolled steel sheet

Claims (2)

[Claims] An apparatus for preventing meandering of a hot-rolled steel sheet provided on an output run-out table of a hot finishing rolling mill, comprising a pair of spray nozzles for jetting high-pressure water to both side ends of the hot-rolled steel sheet. A meandering preventing device for hot rolled steel sheets. 2. The pressure and / or flow rate of high-pressure water sprayed from the spray nozzle pair can be changed according to the thickness and / or width of a hot-rolled steel sheet.
A meandering prevention device for a hot-rolled steel sheet as described in the above.