JPH01192417A - Method and apparatus for hot rolling - Google Patents

Abstract

PURPOSE:To prevent a strip from bounding and being folded when it passes through a finish rolling mill by holding, guiding and simultaneously rolling the strip by the magnetic force of a magnetic force generating means provided between a rolling mill and a take-up machine. CONSTITUTION:Bar magnets 6 are arranged among hot run table rolls 5 under a hot run spray cooling zone 4 and the strip 9 which is cooled down to a temperature under the Curie Point is attracted by the hot run table rolls 5, 5. Since the attraction force of the magnet 6 is affected by distance, a height controlling mechanism 7 is provided to control such attraction force and release mechanisms 8 are arranged suitably not to accurate the attraction force. Accordingly, the strip 9 can be prevented from being deflected by the attraction force of the magnets 6 and scratches can be prevented from occurring by the contact with the magnets 6.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial Field of Application) The present invention relates to a hot rolling method and an apparatus therefor, in which the trailing end of a strip is transferred from a finishing mill to a winder in a hot strip mill line. The present invention relates to a method and equipment for appropriately suppressing vibrations in the vertical and horizontal directions during reaching the coil and improving the coil winding shape.

(Prior Art) In a hot rolling facility, a finish-rolled strip is wound up in a winding machine.

That is, FIG. 4 shows an example of the equipment arrangement after the finishing mill of a hot strip mill. The strip 9, which has been finished to the desired thickness and width in the finishing mill 1, is rolled to the target value in the hot run spray 4. After being cooled to temperature, it is wound onto a mandrel of a winder 2. The winding machine 2 has a pinch roll 3 just in front of it, which guides the leading end of the strip 9 to the mandrel, and after the tail end of the strip 9 passes through the finishing mill 1, it is guided to a predetermined position between it and the mandrel. The winding tension can be applied.

In such equipment, the relationship between the strip winding shape of the winder 2, the pinch rolls, and the winding tension is that until the tail end of the strip 9 passes through the finishing mill 1, the mandrels of the finishing mill 1 and the winding machine 2 are Therefore, the centering effect of the side guide 10 in front of the winder 2 is sufficiently exerted, and a good winding shape can be obtained.

Furthermore, even after the tail end of the strip 9 passes through the finishing mill 1, the tension is controlled between the pinch roll 3 and the mandrel. Conventionally, the speed of the hot run table roller 5 is generally controlled so that it has a lead opposite to the speed of the strip 9, since the tail end of the strip between the two ends has no tension.

In addition, a facility was proposed in Japanese Patent Publication No. 62-2501 in which another pinch roll and side guide were installed in the finishing mill, that is, two pairs of pinch rolls and a side guide were used to improve the centering force. The tension fluctuation that occurs when the tension control is switched at the moment the strip exits the finishing mill promotes the swinging of the strip.
Control methods such as No. 38719 and Japanese Patent Publication No. 61-14055 have also been proposed.

(Problems to be Solved by the Invention) In the case of the conventional general method described above, the frictional force with the table roller 5 is supposed to be applied in a manner that resists the pinch roll 3, but in reality, the reaction force due to the release of tension and strip 9 is the 4th
As shown in the figure and FIG. 5, it jumps and has almost no effect as a back tension. In a non-tensioned state, the rigidity of the strip is weakened, and when the strip jumps, it often tilts in the width direction and moves up and down, so the centering effect of the side guide 10 is not exerted, and a wound outer peripheral tube of the coil is likely to occur. In addition, when using only the pinch roll 3, force was required to apply sufficient tension to obtain a tight winding condition, and pressing the plate to the extent that the plate thickness changed resulted in poor leveling and uneven wear of the pinch roll 3. In this case, the strip may shift in the width direction, resulting in poor winding shape. Furthermore, the strip 9 is bent by the pinch rolls 3 due to the bounce of the strip that occurs immediately after the tail end is removed from the finishing mill, resulting in a defective shape and, in some cases, the strip breaking, causing great damage.

The above-mentioned Special Publication Publication No. 62-2 was proposed in response to these problems.
No. 501 does not solve the phenomenon in which the strip between the front pinch roll and the finishing mill becomes tensionless the moment it passes through the finishing mill, and is therefore ineffective against folding.

``The methods of JP-A-62-38719 and JP-A-61-14055 merely perform stable tension control immediately after the strip passes through the finishing mill, so problems such as insufficient tension due to pinch rolls still occur. It is unresolved.

"Structure of the Invention" (Means for Solving the Problems) The present invention has been devised after repeated studies to solve the problems of the conventional products as described above, and is as follows.

1. When winding a hot strip that has been hot rolled or is being hot rolled with a mandrel, the strip is held and guided by the magnetic force of a magnetic force generating means provided between the rolling machine and the winding machine. A hot rolling method characterized by winding.

2. In a hot strip mill facility having a hot rolling mill and a winding machine for winding the hot strip rolled by the hot rolling mill on a mandrel, a strip bus passing between the rolling mill and the winding machine; A hot rolling apparatus characterized by being provided with a magnetic force generating means that applies an attractive force downward to the line.

(Function) The magnetic force of the magnet generating means attracts the strip to the hot run table roll at least before the tail end of the strip passes through the finishing mill. This prevents the tail end of the strip from bouncing when it passes through the finishing mill and avoids folding.

As mentioned above, by preventing the tail end of the strip from jumping when it passes through the finishing mill, the centering effect of the side guide can be fully utilized, and even before the tail end of the strip leaves the finishing mill, the hot run table is set in a direction opposite to the speed of the strip. Even after the tail end of the strip has passed through the finishing mill, a tension proportional to the magnetic force that attracts the strip to the hot run table roll is applied.

Therefore, the occurrence of a coil outer circumferential cylinder is also prevented.

(Example) To explain the specific embodiment of the present invention shown in the attached drawings, as shown in FIG. A hot run spray cooling zone 4 is provided above the bus line of the hot strip 9 to cool the strip 9 and wind it onto the mandrel of the winder 2 via the side guide 10 and the pinch roll 3. Although the present invention is similar to that of the conventionally known one, in the present invention, a bar magnet 6 is disposed between the hot run table rolls 5 in the Honran spray cooling zone 4 and thereafter, and the temperature is lowered to below the Curie point. The strip 9 is adsorbed onto the hot run table roll 5.5.

It is well known that the attraction force of the magnet 6 is greatly affected by the distance, and the height adjustment mechanism 7 is used to adjust the attraction force.
As shown in Fig. 1(b), a detachment mechanism 8 for preventing the attraction force from acting is appropriately arranged, and the magnet 6 is arranged as shown in Fig. 1(C). Preferably, they are arranged alternately on the drive side and the operation side at a certain distance off-center. That is, this is because the attraction force of the magnet 6 causes the strip 9 to move to the fifth
As shown in the figure, it is bent to prevent scratches from coming into contact with the magnet 6, and to cause a slight partial deflection 11 in the width direction as shown in Fig. 2. The staggered arrangement makes the strips 9 difficult to deform.

However, the present invention is not limited to arranging the magnets 6 in a staggered manner as described above; for boat fishing, they may be arranged as shown in FIG. That is, when the magnets 6 are arranged as shown in Fig. 3, the strip 9 tends to curve as shown in the figure at the magnet 6 part, but it is possible to adjust the setting position of the magnet 6 or the degree of magnetic force. This allows the door to be lowered as it curves, as shown by the imaginary line in FIG. In some cases, the north and south poles of the magnet may be alternately set on opposite sides.

To explain the results of concretely implementing the method of the present invention using such equipment, we will summarize the outer circumferential tube generation rate (number of coils %) for the coils obtained in winder 2, and show that the method of the present invention is not implemented using the same equipment. A comparison with the conventional method is shown in the following table, and by implementing the method of the present invention, it was possible to significantly reduce the occurrence of outer peripheral tubes. This effectively prevents the strip from bouncing and shaking after passing through the finishing mill.
It is self-evident to show that it has been suppressed.

"Effects of the Invention" According to the present invention as explained above, it is possible to effectively prevent and suppress the bouncing and swinging of the tail end of the strip when it passes through the finishing mill, and to prevent the occurrence of outer circumferential tubes, thereby ensuring proper coil winding. This invention enables stable hot strip rolling operations to be carried out smoothly depending on the shape, and is industrially highly effective.

[Brief explanation of the drawing]

The drawings show the technical contents of the present invention,
The figure is an explanatory diagram showing an overall side view, a partial vertical sectional view and a plan view of one example of the apparatus according to the present invention, and Figure 2 shows the subsequent movement of the strip into the finishing mill. It is a front view of a state. In these drawings, 1 is a finishing rolling mill, 2 is a winding machine, 3 is a pinch roll, 4 is a cooling spray, 5 is a hot run table roll, 7 is a height adjustment mechanism, 8 is a detachment mechanism, 9 is a strip, 10 indicates a side guide. 2nd 3rd day 4th day 5th day

Claims (1)

[Claims] 1. When a hot strip that has been hot-rolled or is being hot-rolled is wound up using a mandrel, the strip is heated by the magnetic force of a magnetic force generating means provided between a rolling machine and a winding machine. A hot rolling method characterized by winding while holding and guiding. 2. In a hot strip mill facility having a hot rolling mill and a winding machine for winding the hot strip rolled by the hot rolling mill on a mandrel, a strip bus passing between the rolling mill and the winding machine; A hot rolling apparatus characterized by being provided with a magnetic force generating means that applies an attractive force downward to the line.