JPH09192720A - Hot strip mill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of flying and meandering by running a running carriage from the starting end toward the finishing end in a cooling line while providing a strip with tension in the condition that the chip of the strip is coiled onto a coiler and coiling the strip onto the coiler at the finishing end of the cooling line. SOLUTION: When the chip of the strip 6 leaves out of a finish rolling mill 1, the same is simultaneously held between a pinchroll 10 in front of the coiler and introduced into the coiler 2, and the same is coiled around the mandrel of the coiler 2. At the same time, the running carriage 9 is begun to accelerate toward the finishing end of a strip cooling line 3, and synchronized to the rolling velocity in a short time. During this time period, the rotating velocity of the mandrel of the coiler 2 is controlled so as to always provide the strip 6 with a appropriate tension.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a hot strip rolling mill (hot strip mill).

[0002]

2. Description of the Related Art In a hot strip rolling mill, a strip rolled by a finishing mill to a predetermined plate thickness is
Before being wound up by the mandrel of the down coiler,
A strip cooling line provided between the finish rolling mill and the down coiler cools the coil to a predetermined winding temperature. This strip cooling line consists of a run-out table consisting of several hundred driven roller tables and a water spray cooling device or water laminar cooling device. The lower surface of the strip conveyed on the runout table is cooled, and the upper surface of the strip is cooled by cooling water jetted from above the runout table.

[0003]

By the way, when the strip is conveyed at a high speed by the roller table type run-out table as described above, a so-called flying phenomenon occurs in which the tip of the strip floats upward, which hinders the introduction of the tip of the strip into the down coiler. May come. Therefore, until the tip of the strip winds around the mandrel of the down coiler, the transport speed must be suppressed to about 700 m / min, and the capacity of the finish rolling mill (maximum 1500 m / min.
However, the productivity cannot be improved.

As a technique for preventing such inconvenience, Japanese Patent Publication No. 25214/1990 proposes a method of attracting a strip onto a runout table by electromagnetic force. However, since the electromagnetic force has the property of being inversely proportional to the square of the distance, if a flying phenomenon occurs due to some disturbance, it is virtually impossible to adsorb it again on the runout table, preventing the rising of the strip tip. Therefore, this technique is not sufficient as a measure for realizing high-speed conveyance.

The present invention solves the problem imposed on the prior art, that is, the inconvenience that a flying phenomenon occurs when a strip is conveyed at a high speed on a run-out table, and the sheet passing capability of a finish rolling mill is eliminated. It is an object of the present invention to provide a high-efficiency hot strip steel rolling facility improved so as not to hinder the above.

[0006]

In order to achieve such an object, in the present invention, a finish rolling mill is used to deliver the
A coiler for winding the strip cooled in the strip cooling line is mounted on a traveling carriage that can be moved in synchronization with the delivery speed of the strip on a guide rail extending over the entire length of the strip cooling line. While the tip of the strip is wrapped around the coiler, the traveling carriage is run from the beginning to the end of the cooling line while applying tension to the strip, and the strip is wound around the coiler at the end of the cooling line. did.

Particularly, as a strip cooling line, a pinch roll and a cooling water jetting device which can be retracted from the course of the traveling vehicle only while the traveling vehicle passes and which can be brought close to the upper and lower surfaces of the strip after the traveling vehicle passes. To have. Further, the strip cooling line is provided with a magnetism generating means for sucking the strip.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows a final stand of a finish rolling mill 1 and a strip cooling line 3 in a hot strip rolling mill according to the present invention. Strip cooling line 3
Is composed of a large number of pinch rolls 4 and a pair of cooling water jetting devices 5 which are vertically arranged in a row at appropriate intervals in the sheet passing direction. The pinch rolls 4 and the cooling water injection devices 5 are alternately arranged in the passing direction.

The pinch roll 4 is composed of a pair of upper and lower rolls, and each roll is supported so as to be vertically movable toward and away from each other. Each of the pinch rolls 4 sandwiches the upper and lower surfaces of the strip 6 delivered from the finish rolling mill 1 with a predetermined pressing force, each is given a driving force, and the rotation speed is freely controlled. . Similar to the pinch roll 4, the cooling water jetting device 5 is composed of vertically paired cooling water jetting devices, and each cooling water jetting device 5 is supported on the upper and lower surfaces of the strip 6 so as to be movable toward and away from each other. .
On the surface of the cooling water jetting device 5 facing the strip 6,
A plurality of cooling water nozzles are provided so that cooling water can be sprayed on the upper and lower surfaces of the strip 6.

A guide rail 7 is provided on the strip cooling line 3 so as to extend along the plate passing direction. On the guide rail 7, wheels are regulated by the upper and lower guide rails 7 to prevent the wheels from floating, and for example, a traveling carriage 9 driven by a pinion gear that meshes with a rack gear extending parallel to the guide rail is mounted. It is placed. This traveling carriage 9 is provided with a coiler front pinch roll 10 for gripping the tip end of the strip 6 sent from the finishing rolling mill 1 from above and below and guiding it to the rear coiler, and for winding the strip 6 The coiler 2 of is installed.

Next, the operating procedure of the above embodiment will be described.

In the state before the tip of the strip 6 is delivered from the finishing rolling mill 1, as shown in FIG.
All the carrier rolls 4 and all the cooling water jetting devices 5 have moved to positions vertically separated from each other and are on standby. Then, the traveling vehicle 9 equipped with the coiler 2 rotates the pinch roll 10 in front of the coiler at a peripheral speed slightly higher than the delivery speed of the strip 6 from the finishing rolling mill 1 in the vicinity of the exit of the final stand of the finishing rolling mill 1. It is waiting in the state where it was made.

When the tip of the strip 6 exits the finish rolling mill 1, the tip of the strip 6 is immediately gripped between the coiler front pinch rolls 10 and introduced into the coiler 2, and the tip of the strip 6 is placed on the mandrel of the coiler 2. Wrap around. Almost at the same time, the traveling carriage 9 starts accelerating toward the end of the strip cooling line 3 and synchronizes with the rolling speed in a short time. During this time, the mandrel of the coiler 2 is controlled in its rotation speed so that the strip 6 is always given an appropriate tension.

On the other hand, each pair of the pinch roll 4 and the cooling water jetting device 5, which have been retracted in both the upper and lower directions, sequentially move toward the upper and lower surfaces of the strip 6 as the traveling vehicle 9 passes. And the pinch roll 4 is a strip 6
The rotation speed of the strip 6 is controlled so as to contact the upper and lower surfaces of the strip 6 and maintain the tension of the strip 6 within a predetermined range. Cooling water is sprayed from the cooling water jetting device 5 toward the upper and lower surfaces of the strip 6. In this way, the strip 6 is cooled in a state in which an appropriate tension is always applied, so that the plate shape after cooling is significantly improved. Moreover, since the cooling water jetting device 5 can also move toward and away from the surface of the strip 6, the cooling water jetting device 5 can be brought close to the surface of the strip 6 and rapidly cooled after the traveling carriage 9 passes therethrough. The length can be reduced. In addition to this, since the scale thickness generated on the surface of the strip 6 becomes small, the load of pickling in the next step is reduced.

The strip wound around the coiler 2 until the speed of the traveling carriage 9 reaches the rolling speed may be rapidly cooled while rewinding by making the speed of the traveling carriage 9 higher than the rolling speed. Also, in the case of a strict material that causes problems due to partially different cooling modes,
Before the speed of the traveling carriage 9 is synchronized with the rolling speed, the coiler 2
The portion wound up on the substrate will be cut off, but the yield will not drop significantly compared to the conventional case.

When the traveling carriage 9 reaches the end of the strip cooling line 3, the mandrel of the coiler 2 is rotated to wind up the strip 6 continuously fed from the finish rolling mill 1. At this time, by constantly applying back tension to the strip 6 with the pinch roll 4,
The strip 6 is wound evenly without slack. Therefore,
Since the strip 6 can be decelerated on the strip cooling line 3, it is not necessary to reduce the rolling speed of the strip tail end in the finish rolling mill 1.

When the tail end of the strip 6 passes through the pinch roll 4, the tail end may be swung up and down because the restraining force on the tail end is interrupted. However, each cooling water injection device 5 located below The electromagnetic suction device 12 built in the stub maintains stable running of the tail end. And strip cooling line 3
After the tail end passes through the final pinch roll 4 of No. 1, the strip 6 is restrained by the pinch roll 10 before the coiler. As a result, the stability of the tail end of the strip when wound around the coiler 2 is increased, and it is not necessary to significantly reduce the transport speed of the tail end.

When one coil has been wound, the traveling carriage 9 must be returned to the position immediately after the finish rolling mill 1 in preparation for the delivery of the next strip, but this return time becomes a loss time. In order to prevent this loss time from occurring, as shown in FIG. 3, a return-only guide rail 21 is provided in parallel with the guide rail 7 provided in the strip cooling line 3, and these two sets of guide rails 7 It is possible to connect short rails 22a and 22b to the extent that the traveling carriage 9 can be mounted to each of the start end portion and the end portion of 21 and traverse rails so that the short rails 22a and 22b can be laterally moved laterally. 23a and 23b may be provided so that the two traveling carriages 9 and the short rails 22a and 22b are alternately moved laterally. With this configuration, while one traveling carriage is traveling on the guide rail 7, the other traveling carriage is returned to the dedicated guide rail 2
When the pinch roll 4 and the cooling water jetting device 5 are opened up and down after the coil has been wound up and the coil is finished, the other traveling bogie has already returned to the starting end side. Is moved laterally together with the short rail 22a on the starting end side to align with the guide rail 7 of the strip cooling line 3, and one traveling carriage that has traveled to the end of the strip cooling line 3 is laterally moved together with the short rail 22b on the end side. Since it can be aligned with the return-only guide rail 21, a standby state for the delivery of the next strip can be realized without causing a loss time.

[0020]

As described above, according to the present invention, since the leading end of the strip fed from the finish rolling mill is mechanically constrained and the traveling carriage runs in synchronization with the feeding speed of the rolling mill, the strip is stripped. The cooling line can be threaded by applying a constant tension to. This can prevent the occurrence of flying or meandering over the entire length of the strip. Therefore, the strip passing speed can be increased corresponding to the capability of the finish rolling mill, and a great effect can be achieved in improving productivity.

Further, a constant tension can be applied to the strip during cooling, and the cooling efficiency can be improved by bringing the cooling water jetting device close to the strip, so that the cooling state is made uniform over the entire length of the strip. Therefore, the quality of the strip may be improved.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram showing a state before passing a strip to a strip cooling line in the equipment of the present invention.

FIG. 2 is a conceptual configuration diagram showing a state where a strip is passed through a strip cooling line in the equipment of the present invention.

FIG. 3 is a layout view of guide rails of the traveling carriage.

[Explanation of symbols]

 1 Finishing Roller 2 Coiler 3 Strip Cooling Line 4 Pinch Roll 5 Cooling Water Injection Device 6 Strip 7 Guide Rail 9 Traveling Cart 10 Coiler Front Pinch Roll 12 Electromagnetic Suction Device 21 Return-only Guide Rail 22a / 22b Short Rail 23a / 23b Traverse Rail

Claims (4)

[Claims] 1. A hot strip rolling mill having a finish rolling mill, a strip cooling line for cooling the strip fed from the finish rolling mill, and a coiler for winding the cooled strip, wherein the coiler Is mounted on a traveling carriage that can move on a guide rail extending over the entire length of the strip cooling line in synchronization with the delivery speed of the strip, and the tip of the strip is wound around the coiler. While applying tension to the strip in this state, the traveling carriage is made to travel from the start end to the end of the cooling line, and the strip is wound around the coiler at the end of the cooling line. Strip steel rolling equipment. 2. The strip cooling line has pinch rolls that can be retracted from the path of the traveling carriage only while the traveling carriage passes and can contact both upper and lower surfaces of the strip after the traveling carriage passes. The hot strip steel rolling facility according to claim 1, wherein the hot strip rolling mill is a rolling mill. 3. The cooling water jetting device, wherein the strip cooling line can be retracted from the path of the traveling carriage only while the traveling carriage passes, and can be brought close to the upper and lower surfaces of the strip after the traveling carriage passes. The hot strip rolling mill according to claim 1 or 2, characterized in that 4. The hot strip rolling mill according to claim 1, wherein the strip cooling line is provided with a magnetism generating means for sucking the strip.