JPH10192907A - Hot rolling equipment and hot rolling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent the generation of strip breaking in the rear end part of band steel without damaging the shape of the band steel. SOLUTION: A light reduction rolling mill 7 between which and the final stand rolling mill F7 the band steel 4 is restrained is arranged in the vicinity of the outlet side of the final stand rolling mill F7 in a tandem type finishing mill and also crossing devices such as a crossing cylinders 20 and pressing cylinders 21 as shape controlling means of the band steel 4 are provided on the light reduction rolling mill 7. When the rear end part of the band steel 4 is tailed off through the work rolls of the 1st rolling mill this side of the final stand, the band steel 4 is clamped at two places of the work rolls 11 of the final stand rolling mill F7 and light reduction rolls 16 of the light reduction rolling mill 7 and, by the restraining effect, meandering is prevented and the generation of strip breaking is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot rolling equipment and a hot rolling method for a thick plate or a strip, and more particularly, to a method for preventing narrowing of a rear end portion of a strip when a thin strip is rolled. The present invention relates to a rolling facility and a rolling method.

[0002]

2. Description of the Related Art In a general strip hot rolling plant, a heating furnace is provided downstream of a lump mill or a continuous casting apparatus, and a slab is roughly rolled continuously in a discharge line of the heating furnace. A reverse type rough rolling mill using steel (sheet bar) is provided.
On the downstream side of the rough rolling mill, a finish rolling mill for finishing rolling the rough-rolled steel strip is arranged, and is located downstream of the finishing rolling mill, after the finish rolling and cooling. A down coiler for winding a strip of steel (strip) into a coil is disposed. The finishing mill includes a tandem-type rolling mill in which a plurality of rolling mills (for example, 7 stands) are arranged in a row, and a reversible rolling mill having a coiler furnace on a front surface and a rear surface of a work roll. Used.

[0003] Accordingly, a slab having a thickness of, for example, 250 mm manufactured by the continuous casting apparatus or the like is cut into a predetermined length and then heated and kept in a heating furnace. The slab discharged from this heating furnace is rolled into a strip having a thickness of 30 mm to 50 mm by multi-stage (for example, three-stage) reverse rolling by a rough rolling mill, and is sent to a finish rolling mill. In this finishing mill, the steel strip is finish-rolled to a thickness of 2.3 mm or less by a plurality of stages of rolling or a plurality of repetitive rollings, and the strip is wound on a winder through a cooling device.

[0004]

In the above-mentioned hot strip rolling equipment for a steel strip, when a finishing rolling mill having a plurality of stands of rolling mills arranged in a row is used, the rear end of the steel strip is formed. When the rolling mill of each stand in the finish rolling mill passes through, the rear end of the steel strip is not restrained, and the rear end of the steel strip meanders in the sheet width direction. Furthermore, in the case of a thin strip of steel, this meandering causes a phenomenon in which the rear end of the strip of steel is bent and passed through due to collision with a side guide or the like, that is, so-called narrowing occurs. In particular, when the rolling mill on the subsequent stage, where the sheet thickness becomes thin, passes through the tail, the narrowing is likely to occur due to the low rigidity of the steel strip.

[0005] Therefore, when the rolling mill in front of the last stage passes through the bottom, the narrowing is particularly likely to occur because the binding force is reduced most in addition to the thinner strip thickness. Become. When rolling is performed by biting the rear end of the strip that has been drawn, the work roll of the rolling mill is scratched,
The work roll may be cracked or broken. For this reason, when the work roll has a flaw, it is necessary to immediately reassemble the work roll assembly, and the number of times of roll change per time increases, which causes a problem that the downtime of the apparatus increases.

In recent years, in order to prolong the life of a work roll and reduce the number of roll changes per hour, a high-speed roll using high-speed tool steel as a material for the roll surface is used for a work roll of a finishing mill. Have been. However, since the high-speed roll has a large thermal expansion and causes the meandering of the steel strip, the above-mentioned narrowing is more likely to occur, and when a crack is generated on the roll surface, the progress is rapid. For this reason, at present, it is not possible to use a high-speed roll in the final stage of the finishing mill.

[0007] Even when a reversible finishing mill having a coiler furnace on the front and rear sides of a work roll is used, if the strip is rolled and thinned, the rear end becomes thin. When the front coiler furnace nest roll or the rear coil mill furnace skirt roll passes through the tail, the rear end portion meanders in the width direction of the sheet, and the narrowing is likely to occur. Therefore, the same problem as in the case of using a finishing rolling mill having a plurality of rolling mills arranged in a row as described above occurs.

[0008] In the hot strip rolling equipment for a thick plate, the reduction does not occur as in the hot rolling equipment for a steel strip, but one or two reversible rolling mills are connected to the rear end of the thick plate. When the bottom of the thick plate is removed, the rear end of the thick plate is no longer restrained as in the finishing mill of the hot strip rolling equipment, so that the rear end of the thick plate meanders in the width direction. As a result, there is a problem that the high-speed roll having a large thermal expansion and causing the meandering of the thick plate cannot be further used.

The present invention has been made in view of the above circumstances, and provides a hot rolling equipment and a hot rolling method capable of effectively preventing meandering of a rolled material without impairing the shape of the rolled material. With the goal.

[0010]

The hot rolling equipment according to the present invention for achieving the above object is configured as follows. (1) A finish rolling mill for finish-rolling the rolled material is provided, and a light reduction rolling mill capable of restraining the rolled material between the finish rolling mill and the rolling mill is disposed near the exit side of the finish rolling mill. The rolling mill is provided with shape control means for the rolled material.

(2) A heating furnace for heating the slab, a rough rolling mill for roughly rolling the heated slab to form a strip, and a finish for finish rolling the rough-rolled strip to a predetermined thickness. A rolling mill and a down coiler for winding the finished rolled steel strip into a coil shape, wherein the finishing mill has a plurality of stand rolling mills arranged in a row, and a final stand rolling mill of the finishing mill. A light rolling mill capable of restraining a steel strip between the rolling mill and the rolling mill is disposed near the delivery side, and a shape control means for the steel strip is provided in the light rolling mill.

(3) A reversible finishing mill in which a slab heated in a heating furnace is reciprocated a plurality of times to finish-roll a strip having a predetermined thickness, and the finished rolled strip is wound into a coil. And a light rolling mill capable of restraining the steel strip between the reversible finishing mill and the rolling mill near the rear surface thereof, and controlling the shape of the steel strip in the light rolling mill. Means are provided.

(4) A reversible finishing mill is provided for reciprocating the slab heated in the heating furnace a plurality of times and finish rolling to a thick plate having a predetermined thickness. A light rolling mill capable of restraining the thick plate is arranged between the rolling mill and a shape control means for the thick plate is provided in the light rolling mill.

(5) A shear for cutting a slab having a thickness of 100 mm or less produced by a medium or thin slab continuous casting apparatus into a predetermined length, a heating furnace for heating the cut slab,
A finish rolling mill for finish-rolling the heated slab to a predetermined plate thickness, and a down coiler for winding the finished-rolled steel strip in a coil shape, wherein the finish rolling mill includes a plurality of stand rolling mills. In addition, a light rolling mill capable of restraining a steel strip between the finishing mill and the final stand rolling mill of the same rolling mill is disposed in the vicinity of the output side of the same rolling mill, and the light rolling mill is provided with the light rolling mill. It is characterized in that a shape control means is provided.

(6) The light reduction roll of the light reduction rolling mill is formed of ceramics including thermal spraying.

(7) The light reduction roll of the light reduction mill is formed of heat-resistant steel.

Further, in the hot rolling method according to the present invention for achieving the above object, when the rolled material is finish-rolled to a predetermined thickness by a finish rolling mill, the vicinity of the exit side or the rear surface of the finish rolling mill is provided. Wherein the rolled material is lightly reduced while controlling the shape by a light reduction rolling mill.

[Action] According to item (1), when the rear end of the rolled material passes through the rolling roll of the finishing mill, the rolled material is reduced by the rolling roll of the finishing mill and the light reduction of the light rolling mill. The roll is pinched between two points, and its restraining effect prevents meandering. Further, the shape of the rolled material is well controlled by the light reduction roll. Also,
When the leading and trailing ends of the rolled material are passed through the rolling rolls, front and rear tensions are applied by the light pressure rolls, and the plate thickness and shape are stabilized.

According to the item (2), when the hot rough-rolled steel strip is hot-finished and rolled to a required thickness sequentially by a tandem-type finish rolling mill, the rear end of the strip is finished by the finish rolling mill. When passing through the rolling roll, the steel strip is sandwiched between the rolling roll and the light reduction roll of the finishing mill, and the restraining effect prevents meandering and avoids narrowing. Others are the same as the item (1).

According to item (3), when the hot rough-rolled steel strip is sequentially hot-finished and rolled to a required thickness by a reversible finishing mill, the rear end portion is rolled by the finishing mill. When removing the roll, the steel strip is sandwiched between the rolling roll of the finishing mill and the light rolling roll, and the restraining effect prevents meandering and avoids narrowing. Others are the same as the item (1).

According to item (4), when the slab is reciprocated a plurality of times by a reversible finishing mill and finish rolled into a thick plate having a predetermined thickness, the rear end of the thick plate is subjected to reversible finish rolling. When passing through the rolling rolls of the mill, the thick plate is sandwiched between the rolling rolls and the light rolling rolls to prevent meandering by its restraining effect. Others are the same as the item (1).

According to item (5), when the slab produced by the continuous casting apparatus for medium or thin slabs is finish-rolled into a strip having a predetermined thickness, the rear end of the strip is rolled by a finishing mill. When removing the roll, the steel strip is sandwiched between the rolling roll and the light rolling roll, and the restraining effect prevents meandering and avoids drawing. Others are the same as the item (1).

According to item (6), since the roll temperature does not easily rise, the cooling of the roll is unnecessary and the sheet temperature does not drop.

According to the item (7), since there is no problem even if the roll temperature increases, the roll temperature is not required and the sheet temperature does not decrease.

According to the hot rolling method of the present invention, meandering of the rolled material is prevented by the restraining effect of the rolling roll of the finishing mill and the light reduction roll, while the shape correcting function of the light reduction roll is achieved. A rolled material having a good shape can be obtained.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The hot rolling equipment and the hot rolling method according to the present invention will be described below in detail with reference to examples.

[First Embodiment] FIG. 1 is a schematic configuration diagram of a hot rolling facility showing a first embodiment of the present invention, FIG. 2 is a side view of a final stand portion of a finishing mill, and FIG. FIG. 2 is a cross-sectional view of the machine.

As shown in FIG. 1, a slab 1 manufactured by a continuous casting device or the like (not shown) is heated and kept in a heating furnace 2. Reverse type rough rolling mills R ₁ , R ₂ , R ₃ are provided continuously on the outlet line of the heating furnace 2 and the rough rolling mills are provided.
A finishing mill F is provided continuously to the outlet lines of R ₁ , R ₂ and R ₃ . The cooling device 3 is provided continuously to the finishing mill F,
The strip 4 finished and rolled by the finishing mill F is cooled by the cooling device 3 and then wound into a coil by the winder 5. In the figure, 6 is a hot run table, and P indicates a pass line.

The finishing mill F is provided with a plurality of stands (seven stands in the illustrated example) of rolling mills F _{1 to} F ₇ arranged side by side, and a light reduction mill (skin pass) is provided at the output side of the rolling mill F ₇ which is the final stand. Mill 7 is arranged. In the illustrated example, the housing 8 of the final stand rolling mill F _{7 and} the housing 9 of the light rolling mill 7 are integrally connected.

As shown in FIG. 2, the final stand rolling mill F ₇
Is constituted by a four-high rolling mill, and a work roll 11 is supported on a housing 8 of the work roll 11 via a work roll chock 10.
2, the rolling force acts. The backup roll 12 includes a backup roll chock 13, a pressure reduction device 14, and a screw-type pass line adjustment device 2.
2 and is supported by the housing 8. In the figure, reference numeral 15 denotes a bender as a means for controlling the shape of the strip 4.

On the other hand, the light reduction mill 7 is constituted by a two-high rolling mill, and a light reduction roll (skin pass roll) 16 made of ceramics (including ceramic sprayed) is mounted on a housing 9 thereof via a light reduction roll chock 17. Supported. The lower light pressure lower roll chock 17 has a lower surface portion through a flat bearing 18 and a hydraulic pressure upper cylinder 19, and front and rear surfaces thereof have a cross cylinder 20 and a pressing device of a cross device (shape control means of the steel strip 4). While being supported by the housing 9 via the cylinder 21,
The upper / lower pressure roll chock 17 has an upper surface portion through a flat bearing 18 and a screw type pass line adjusting device 22, and the front and rear surfaces thereof are the same as the lower / lower pressure roll chock 17, and a cross cylinder 20 and a pressing device. It is supported by the housing 9 via the cylinder 21.

As shown in FIG. 3, the light pressure lower roll 16 is driven to rotate by a motor (not shown) via a spindle 23 connected to the drive end thereof, and both the drive side and the operation side are crossed. Possible (both cross method).

The slab 1 having a thickness of, for example, 250 mm discharged from a continuous casting device (not shown) or the like is cut into a predetermined length by a cutting device (not shown). Is heated and kept warm. Next, the slab 1 that has exited the heating furnace 2 is sequentially rolled in, for example, three stages by reverse rolling using rough rolling mills R ₁ , R ₂ , and R ₃ to form a strip (sheet bar) 4 having a thickness of about 35 mm. To the finishing mill F. In this finishing mill F, 7 by soft reduction rolling of the rolling mill F ₁ to F ₇ 7 stages by rolling the soft reduction rolling mill 7 stand, finished to a thickness of about 1.2mm rolled steel strip (strip) 4 Is wound on a winder 5 through a cooling device 3 and a hot run table 6.

In the above-mentioned rolling step, the rear end of the strip 4 is a rolling mill just before the final stand in the finishing mill F.
When the work roll of F ₆ has been pulled out, the steel strip 4 is sandwiched between the work roll 11 of the final stand rolling mill F ₇ and the light reduction roll 16 of the light reduction rolling mill 7, so that the strip 4 meanders due to the restraining effect. Is avoided to avoid the occurrence of narrowing down. As a result, finishing mill can also be used high-speed steel roll in the work roll 11 of the final stand rolling mill F ₇ of F, attained is prolonging the roll life.

The restraining effect increases as the distance between the work roll 11 and the light reduction roll 16 decreases, but in the present embodiment, the housing 8 of the final stand rolling mill F ₇ and the light reduction roll 7 Is integrally connected to the housing 9, there is an advantage that the distance can be reduced as much as possible.

Further, by constraining the steel strip 4 by the final stand rolling mill F ₇ and the light rolling mill 7, a change in the tension distribution due to the disorder of the thickness and shape of the steel strip 4 (the width of the steel strip 4). Direction) acts in a direction to suppress the disturbance by a feedback effect.

Further, in this embodiment, due to disposing the soft reduction rolling mill 7 having a shape correction function exit side of the final stand rolling mill F _7, the adverse effect on the shape of the strip 4, soft reduction rolling mill 7 Is effectively avoided by the cross device including the cross cylinder 20 and the pressing cylinder 21 attached to the device. In other words, over the two steps with vendors 15 of the final stand rolling mill F ₇ a cross device soft reduction rolling mill 7 the shape of the strip 4 is well controlled.

Further, in the present embodiment, the light pressure roll 1
6 is formed of ceramics having a low thermal conductivity (including ceramic spraying), the heat of the strip 4 is reduced by the light pressure rolls 16.
Since the roll temperature is hard to rise and the roll temperature does not easily rise, there is an advantage that the roll temperature is not required and the sheet temperature does not drop. Especially,
In this embodiment, the exit side of the final stand rolling mill F ₇ will form adding the pair of soft reduction rolls 16, delivery temperature of the conventional material of the soft reduction rolls 16 are long if the strip 4 is lowered requiring cooling However, since it is made of ceramics, it can be prevented. .

In this embodiment, the final stand rolling mill is used.
Due to the provision of a pair of soft reduction rolls 16 on the outlet side of the F _7, conventionally, it can be shortened previously tail end length of the plate which has been rolled without tension, to improve the sheet thickness precision and the plate shape of the previous tail end I can do it. In other words, conventionally, at the start of finishing rolling in the final strip rolling mill of the steel strip or until the tip of the steel strip is wound by the winder,
The steel strip was rolled in a state where sufficient tension was not applied, and the thickness control during that time was sometimes unstable. However, in the present embodiment, the light reduction of the steel strip 4 by the light reduction roll 16 was performed. Since the support is always performed during finish rolling,
Even before the end portion of the strip 4 is wound by the winder 5, a sufficient tension is maintained in the strip 4 and immediately after the start of the finish rolling of the strip 4 to immediately before the end thereof. Up to this, there is an effect that shape control such as control of plate thickness can be stably performed. The tension can be adjusted by the torque of the electric motor that drives the light pressure roll 16 to rotate. That is, since the light reduction roll 16 is lightly reduced, the tension can be controlled by the driving torque.

[Second Embodiment] FIG. 4 is a side view of a final stand of a finishing mill according to a second embodiment of the present invention.

As shown in the figure, this embodiment is a modification of the final stand rolling mill F ₇ in the first embodiment from 4-high rolling mill to 6-high mill. That is, the final stand rolling mill F ₇ of this embodiment has the intermediate roll 25 interposed between the work roll 11 and the backup roll 12. Other configurations are the same as in the first embodiment.

[0042] This by also by the final stand rolling mill out soft reduction rolling mill is arranged on the side 7 of the F _7, similarly to the first embodiment, restraint effect and tensioning effect is obtained with respect to the strip 4.

[Third Embodiment] FIG. 5 is a side view of a final stand of a finishing mill according to a third embodiment of the present invention.

As shown in FIG., The present embodiment, the final stand rolling mill F ₇ in the first embodiment from 4-high rolling mill, first
As in the case of the light rolling mill 7 in the embodiment, the present invention is changed to a two-high rolling mill having a cross device as shape control means. That is, the final stand rolling mill F ₇ of the present embodiment, the its housing 8, the work roll 11 is supported through the work roll chocks 10. The lower work roll chock 10 is supported by the housing 8 on the lower surface via a flat bearing 18 and a hydraulic pressure upper cylinder 19, and on the front and rear surfaces thereof via a cross cylinder 20 and a pressing cylinder 21 of a cross device. At the same time, the upper work roll chock 10 has a housing on the upper surface via a flat bearing 18 and a screw type pass line adjusting device 22, and on the front and rear surfaces thereof via a cross cylinder 20 and a pressing cylinder 21 of a cross device. 8 is supported. Other configurations are first
This is the same as the embodiment.

[0045] This by also by the final stand rolling mill out soft reduction rolling mill is arranged on the side 7 of the F _7, similarly to the first embodiment, restraint effect and tensioning effect is obtained with respect to the strip 4. Further, in this embodiment, since the steel strip 4 is restrained by two two-high rolling mills having a large diameter and high parallel rigidity, it is harder to meander. In addition, the final stand rolling mill F ₇ is usually rolling load
Because it is as small as around 1000TON, a two-high rolling mill is sufficient,
Accordingly, there is obtained an advantage that the size can be reduced, and the mill constant is increased, and the plate thickness accuracy is improved.

[Fourth Embodiment] FIG. 6 is a side view of a reversible finishing mill in a strip hot-rolling equipment showing a fourth embodiment of the present invention.

As shown in the drawing, the rough rolling mills R ₁ , R ₂ , R ₃ (FIG. 1)
), A reversing mill 40, a front coiler furnace pinch roll 41 and a rear coiler furnace pinch roll 42 are arranged on the delivery line, and the front coiler furnace 43, gate 44, and guide 45 are provided above the pass line P. Further, a rear coiler furnace 46, a gate 47, and a guide 48 are arranged. In the vicinity of the rear surface of the work roll 49 (downstream of the pass line P) of the reversible rolling mill 40, the light rolling mill 7 having the shape control means as in the first embodiment is arranged.

According to this, the steel strip 4 is rolled by being reciprocated a plurality of times by the reversible rolling mill 40 while being pinched (lightly reduced) by the light reduction rolls 16 of the light reduction mill 7, and rolled to a predetermined thickness. Hot finish rolling. At this time, when the rear end of the steel strip 4 has passed through the front coiler furnace fin roll 41 or the rear coiler furnace fin roll 42,
Is meandering when the sheet thickness is rolled to 2.3 mm or less, for example.
9 and a light pressure lower roll 16 on the rear surface.
With the restraining effect, meandering can be prevented and the occurrence of narrowing can be avoided. Further, the strip 4 having a good shape can be obtained by the shape correcting function of the light pressure roll 16.

Fifth Embodiment FIGS. 7A, 7B and 7
(C) is a schematic view showing a fifth embodiment of the present invention, and is a schematic configuration diagram of each of a steel strip hot-rolling equipment provided with a medium-thick and thin-slab continuous casting apparatus.

In FIG. 7A, a shear 52 for cutting a slab to a predetermined length and a cutting 52 are provided downstream of a pass line of a continuous slab casting apparatus 51A capable of manufacturing a slab having a thickness of about 90 mm. Rough rolling mills R ₁ and R ₂ are arranged through a heating furnace 2 for heating and keeping the slab heated, and the thickness of the slab is reduced by one-pass rough rolling by these rough rolling mills R ₁ and R _2. 30
It is made into a steel strip 4 of about mm, and once wound around a coil box 53. Thereafter, the steel strip 4 unwound from the coil box 33 is finish-rolled in five stages by a finishing mill F including a plurality of stands (five stands in the figure) and a four-high rolling mill.
For example, it is made into a steel strip 4 having a thickness of 1.2 mm, and is wound around a winder 5 through a cooling device 3.

[0051] Then, proximally out of the work roll 11 of the final stand rolling mill F ₅ of the finishing mill F, soft reduction rolling mill 7 having a shape control means as in the first embodiment are arranged.

In FIG. 7B, a rough rolling mill R ₁ is provided via a shear 52 and a heating furnace 2 downstream of a pass line of a continuous thin slab casting apparatus 51 B capable of producing a slab having a thickness of 60 mm, for example. , place the R _2, according to these roughing mill R _1, R ₂ 1
The steel strip 4 is formed into a strip 4 having a thickness of about 30 mm by rough rolling of a pass, and is once wound around a coiler and kept in a heat retaining furnace 54. Thereafter, the steel strip 4 unwound from the coiler is finish-rolled in six stages by a finishing mill F comprising a plurality of stands (six stands in the figure) and a four-high rolling mill, for example, a steel strip 4 having a thickness of 1.2 mm. And wound up by the winder 5 through the cooling device 3.

[0053] Then, proximally out of the work roll 7 in the final stand rolling mill F ₆ of the finishing mill F, soft reduction rolling mill 7 having a shape control means as in the first embodiment are arranged.

In FIG. 7C, a plurality of stands (in the figure) are provided downstream of the pass line of the continuous thin slab casting apparatus 51C capable of producing a slab having a thickness of 50 mm via the shear 52 and the heating furnace 2. In this example, a finishing mill F composed of four-high rolling mills of 7 stands is directly connected, and the slab coming out of the heating furnace 2 is finish-rolled in seven stages by the finishing mill F, and has a thickness of, for example, 7 mm.
It is made into a 1.2 mm strip 4, passed through a cooling device 3 and wound up by a winder 5.

[0055] Then, proximally out of the work roll 7 in the final stand rolling mill F ₇ of the finishing mill F, soft reduction rolling mill 7 having a shape control means as in the first embodiment are arranged.

Also in these facilities, in the rolling step, when the rear end of the strip 4 passes through the work roll of the rolling mill just before the final stand in the finishing mill F, the strip 4 is rolled to the final stand. to sandwiched by two positions between the work rolls 11 of the machine F ₇ and soft reduction rolls 16 of soft reduction rolling mill 7, to avoid the occurrence of narrowing by preventing meandering by the restraining effect. Further, the strip 4 having a good shape can be obtained by the shape correcting function of the light pressure roll 16.

[Sixth Embodiment] FIG. 8 is a schematic structural view of a thick plate hot rolling equipment showing a sixth embodiment of the present invention.

As shown in the figure, a rough rolling mill R is disposed downstream of a pass line of a heating furnace 2 for heating a slab 1 having a predetermined thickness. 4
A is reciprocated through a reversible rolling mill 40 a plurality of times, and finish-rolled to a predetermined thickness (for example, 6 mm or more). The finish-rolled thick plate 4A is sent to a hot leveler (not shown), and is cooled on a cooling floor after hot straightening.

Further, a light rolling mill 7 having a shape control means similar to the first embodiment is arranged on the rear surface (downstream of the pass line P) of the work roll 49 of the reversible rolling mill 40.

Also in this equipment, in the rolling process,
The thick plate 4A is sandwiched between the work roll 49 of the reversible rolling mill 40 and the light rolling roll 16 of the light rolling mill 7 on the rear surface, and meandering can be prevented by the restraining effect. Further, the strip 4 having a good shape can be obtained by the shape correcting function of the light pressure roll 16.

By the way, there is a thick plate hot rolling equipment without the rough rolling mill R, and the same operation and effect can be obtained in this case also by configuring in the same manner as in the above embodiment.

In each of the above embodiments, an example in which a hydraulic direct-acting cross device is used as the shape control means in the light rolling mill 7 is used. However, as shown in FIG. 9, another cross device is used. You may. That is, as shown in FIG. 9A, the screw 30 is used, as shown in FIG. 9B, the wedge 31 is used, and as shown in FIG. FIG. 9D shows a wedge 31 and a hydraulic cylinder 32 used.
And so on. Further, a vender or a CVC (continuous variable crown) mechanism may be used instead of the cross device.

The material of the pair of upper and lower light pressure rolls 16 is not limited to ceramics, but may be made of heat-resistant steel (roll cooling is not required) which does not hinder the temperature of the rolls or other materials requiring roll cooling. Is also good.

The present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0065]

According to the hot rolling equipment and the hot rolling method according to the present invention, a finishing rolling mill and a light rolling mill having a shape control means disposed near the exit side or the rear surface of the finishing rolling mill. And to prevent the meandering while maintaining the shape of the rolled material satisfactorily, and to avoid the narrowing of the rear end of the strip particularly when rolling a thin strip. Can be. Accordingly, a high-speed roll can be used as a rolling roll of a final stand rolling mill or the like of a tandem finishing mill, and the life of the roll can be extended.

Further, if the light reduction roll of the light reduction rolling mill is formed of ceramics or heat-resistant steel, the cooling of the roll is unnecessary and the sheet temperature does not decrease, so that the exit temperature of the rolled material can be controlled with high precision.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hot rolling facility showing a first embodiment of the present invention.

FIG. 2 is a side view of a final stand of the finishing mill.

FIG. 3 is a cross-sectional view of the light reduction mill.

FIG. 4 is a side view of a final stand of a finishing mill according to a second embodiment of the present invention.

FIG. 5 is a side view of a final stand of a finishing mill according to a third embodiment of the present invention.

FIG. 6 is a side view of a reversible finishing mill in a steel strip hot rolling facility according to a fourth embodiment of the present invention.

7 (a), 7 (b) and 7 (c) show a fifth embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of each of the steel strip hot rolling equipment provided with the continuous casting apparatus of medium thickness and thin slab which shows an Example.

FIG. 8 is a schematic configuration diagram of a hot plate rolling equipment according to a sixth embodiment of the present invention.

FIG. 9 is an explanatory diagram showing another example of the cross device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Slab 2 Heating furnace 3 Cooling device 4 Strip steel 5 Winding machine 7 Light reduction rolling mill 8, 9 Housing 10 Work roll chock 11 Work roll 12 Backup roll 13 Backup roll chock 14 Reduction device 15 Bender 16 Light reduction roll 17 Light reduction roll chock 18 flat bearings 19 hydraulic圧上cylinder 20 cross cylinder 21 pressing cylinder 22 pass line adjusting apparatus R _1, R _2, R ₃ rough rolling mill F (F ₁ ~F ₇₎ finish rolling mill P pass line

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification code FI B21B 37/68 B21B 37/00 135 (72) Inventor Masashi Yoshikawa 4-622 Kanonshinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Research Institute

Claims (8)

[Claims] A finish rolling mill for finish-rolling a rolled material, and a light rolling mill capable of restraining the rolled material between the finish rolling mill and the rolling mill near the outlet side thereof is provided. A hot rolling facility, wherein a rolling material shape control means is provided in a rolling mill. 2. A heating furnace for heating a slab, a rough rolling mill for rough rolling the heated slab to form a strip, and a finish rolling for finish rolling the rough rolled strip to a predetermined thickness. And a down coiler for winding the finished rolled steel strip into a coil. The finish rolling mill includes a plurality of stand rolling mills arranged side by side, and a final stand rolling mill of the finishing mill is provided. A hot rolling facility comprising: a light rolling mill capable of restraining a steel strip between the rolling mill and a side of the rolling mill; and a shape control means for the steel strip provided in the light rolling mill. 3. A reversible finishing mill in which a slab heated in a heating furnace is reciprocated a plurality of times to finish-roll a strip of a predetermined thickness, and the finished rolled strip is wound into a coil. A down coiler, and a light rolling mill capable of restraining the steel strip between the reversible finishing mill and the rolling mill near the rear face thereof, and a shape control means of the steel strip in the light rolling mill. A hot rolling facility characterized by having: 4. A reversible finish rolling mill for reciprocating a slab heated in a heating furnace a plurality of times to finish-roll a slab to a thick plate having a predetermined thickness. A hot rolling mill, further comprising a light rolling mill capable of restraining the thick plate between the rolling mill and the light rolling mill provided with means for controlling the shape of the thick plate. 5. A shear for cutting a slab having a thickness of 100 mm or less manufactured by a medium or thin slab continuous casting apparatus into a predetermined length, a heating furnace for heating the cut slab, and a heated slab. A finish rolling mill that finish-rolls the strip to a predetermined thickness, and a down coiler that winds the finished rolled steel strip in a coil shape, and the finish rolling mill includes a plurality of stands of rolling mills arranged in line. A light rolling mill capable of restraining a steel strip between the finishing mill and the final stand rolling mill is disposed near the rolling mill, and a shape control means for the steel strip is provided in the light rolling mill. Hot rolling equipment. 6. The method according to claim 1, 2, 3, 4, or 5,
A hot rolling equipment wherein the light reduction roll of the light reduction rolling mill is formed of ceramics including thermal spraying. 7. The method according to claim 1, 2, 3, 4, or 5,
A hot rolling equipment, wherein the light reduction roll of the light reduction mill is formed of heat-resistant steel. 8. When the rolled material is finish-rolled to a predetermined thickness by a finish rolling mill, the rolled material is lightly reduced while the shape thereof is controlled by a light rolling mill near the exit side or the rear surface of the finish rolling mill. Hot rolling method.