JPH11207402A - Hot steel strip rolling apparatus and rolling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a space as well as to suppress temp. lowering of a hot slab by arranging a furnace to accommodate an unrolled slab at a inlet side of a rough rolling mill, arranging a slab width adjusting rolling mill at an inlet side of the furnace and directly connecting the rough rolling mill with a finish rolling mill. SOLUTION: A slab width adjusting rolling mill 31 is arranged at an inlet side of a furnace 3, a rough rolling mill 7 and a finish rolling mill 13 are arranged in tandem, a slab 4 is rolled simultaneously over both the rough rolling mill 7 and the finish rolling mill 13. Accordingly, a slab speed is slowed at an inlet side of the furnace 3, but the temp. lowering due to heat radiation from a slab surface is suppressed due to the furnace arranged. Further, the required rolling load and rolling power are decreased resulting from lowering of rough rolling speed, energy saving is obtained, high rolling reduction is made possible, a number of rough rolling stands is decreased. The slab is not rolled over both a width adjusting drawing machine 31 and the rough rolling mill 7, the width adjusting drawing machine 31 is rolled at its own high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot strip rolling equipment which includes a rough rolling equipment and a finish rolling equipment and manufactures a strip from a hot slab material.

[0002]

2. Description of the Related Art Conventionally, various types of hot strip rolling equipment for manufacturing a strip by hot and rough rolling and finish rolling of a slab material have been disclosed.

In the technique disclosed in Japanese Patent Application Laid-Open No. Hei 6-320202, a slab material is reduced in thickness by a rough rolling facility consisting of several rough rolling mills to form a strip material, and then the strip material is once wound and coiled. I have to. Then, the coil-shaped strip material wound up at the unwinding position is unwound, and is subjected to finish rolling by a finish rolling facility including several finishing mills to produce a strip. In addition, this technique specifies a work roll diameter, a roll drive, and the like of a finish rolling facility, and performs high-pressure rolling and low-speed rolling.

Japanese Patent Application Laid-Open No. 5-161902 discloses a technique in which a slab material is reduced in thickness by a rough rolling facility consisting of several rough rolling mills to form a strip material, and thereafter, a rear end portion of the preceding strip material is formed. It is joined to the leading end of the subsequent strip. And
The long strip material after joining is subjected to finish rolling by a finish rolling facility including several finishing mills to produce a strip.

[0005]

Conventionally, in the above-described hot strip rolling equipment for producing a strip from a hot slab material, the rough rolling equipment and the finish rolling equipment are separated at a distance of about 100 m. Had been arranged. And the strip material rolled from the hot slab material by the rough rolling equipment was not rolled over both.

That is, since the finish rolling speed is limited,
If the rough rolling mill equipment and the finish rolling mill equipment are directly connected and rolled, there is a problem that the speed of the slab on the entrance side of the rough rolling mill is low, and the temperature of the slab is lowered due to heat radiation.

[0007] For example, it is assumed that the rolling speed at the exit side of the finishing rolling mill for producing a hot strip material having a thickness of 1.2 mm is high-speed rolling such as 1500 m / min. However, the speed of the slab on the entry side of the row of the rough rolling mill is such that the thickness of the normal slab is 242 mm.
(1.2 / 242) x 1500 = 7.43 m / min
Because of the low speed, it cools down due to heat radiation.

Due to such a problem, conventionally, when the distance between the rough rolling equipment and the finish rolling equipment is to be made as short as possible, as disclosed in Japanese Patent Laid-Open No. -If a rewinding machine is arranged or if it is desired to continuously roll the rolled material, as in Japanese Patent Laid-Open No. 5-161902, a joining machine is provided between the rough rolling equipment and the finish rolling equipment, As described above, the rolled material does not straddle between the rough rolling mill row and the finish rolling mill row, and the rolling work is separately performed at a large speed.

[0009] It is an object of the present invention to provide a tandem arrangement of a rough rolling facility and a finish rolling facility so as to reduce the space of the facility and to suppress a temperature drop of the hot slab.

[0010]

The hot strip rolling equipment according to the present invention comprises a rough rolling equipment for roughly rolling a slab hot and a finish rolling for producing a strip by finishing and rolling a slab which has been roughly rolled. In the hot strip rolling equipment provided with the equipment, the rough rolling equipment and the finishing rolling equipment are arranged in tandem, and the slab is simultaneously straddling the rough rolling equipment and the finishing rolling equipment. The rough rolling equipment and the finish rolling equipment are arranged to perform rolling, and further, a furnace for storing a slab of an unrolled portion is provided on an entrance side of the rough rolling equipment, and a slab is provided on an entrance side of the furnace. A width-adjusting rolling mill is provided.

The rolling method of the hot strip rolling equipment according to the present invention comprises a rough rolling step of roughly rolling the slab hot and a finish rolling step of finishing rolling the roughly rolled slab to produce a strip material. In the rolling method of hot strip rolling equipment including
Before the rough rolling step, performing width adjustment rolling, and then performing a rough rolling while storing the slab of the unrolled portion in a furnace,
Rolling the slab over a tandem-arranged rough rolling facility and a finishing rolling facility.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a rough rolling facility and a finish rolling facility for stretching a hot slab to a strip material are arranged in tandem such that the slab is rolled over both. Then, a furnace for storing the unrolled portion of the slab is provided on the entry side of the rough rolling equipment, and a slab width adjusting rolling mill is provided on the entry side of the furnace. Here, the distance between the slab width adjusting rolling mill and the rolling mill of the rough rolling equipment is set apart so that the slab does not straddle both.

A descaling device may be provided on at least one of the entrance and exit sides of the slab width adjusting rolling mill disposed on the entrance side of the furnace.

The arrangement of the equipment arranged on the outlet side of the furnace is as follows:
It is desirable that the draining pinch roller, the descaling device, and then at least one rough rolling mill be used.

In the above, more preferably, at least two or more rough rolling mills are arranged, and at least the width adjusting rolling mill is arranged on the entry side of the second rough rolling mill. However, the rolling reduction in the first rough rolling mill is increased to 30% or more.

As described above, since the rough rolling equipment and the finish rolling equipment for reducing the thickness of the hot slab to the strip material are arranged in tandem so that the slab is rolled over both, the compact slab having a small space is required. Equipment.
In addition, although the progress speed of the slab rolling operation on the entrance side of the rough rolling facility is slow, the entrance side of the rough rolling facility is provided with a furnace for accommodating the slab of the unrolled portion, so that heat radiation from the slab surface is provided. The heat loss caused by the slab is small, and the temperature of the slab is suppressed from being lowered. And, the distance between the end of the furnace and the first rough rolling mill of the rough rolling equipment is not provided with a width adjusting rolling mill, and a draining device and a descaling device are arranged. Therefore, heat radiation from the slab surface can be minimized despite the extremely slow traveling speed of the slab on the entry side of the first rough rolling mill.

In the width adjustment of the slab, the width adjustment rolling mill is provided on the entrance side of the furnace for storing the unrolled slab, and the slab is rolled over the rough rolling mill having a low speed. Therefore, rolling can be performed at a high speed independently of the rough rolling mill. This reduces heat radiation from the slab surface and eliminates the need to install a width adjustment rolling mill on the entrance side of the first rough rolling mill of the rough rolling equipment. Distance can be minimized. That is, the rolling speed of the width adjusting rolling mill and the rough rolling speed of the rough rolling equipment are individually controlled. In addition, since the scale is removed by the descaling device provided on the entrance side or the exit side before the width-adjustment rolling, the maintainability can be improved without bringing the scale into the furnace.

At the entrance of the second rough rolling mill from the entrance of the rough rolling equipment, a width adjusting rolling mill is provided. At this position, the speed of the slab is increased by a large pressure exceeding 30% in the first rough rolling mill. , The heat radiation from the slab can be reduced. With this width-adjusting rolling mill, it is possible to perform width-reducing rolling for compensating for the spread of the sheet width due to reduced-thickness rolling in the first rough rolling mill and the second rough rolling mill, thereby ensuring the accuracy of the strip width. .

Since the rolled material is rolled over the rough rolling equipment and the finish rolling equipment, the rolling speed of the finish rolling equipment is the same as the conventional one, but the rough rolling speed is independent of the conventional finish rolling equipment. Extremely slow compared to placement. In other words, the conventional rough rolling speed is about 200 to 300 m / min at the final outlet side, but in the arrangement of the present invention, it is as low as 50 m / min or less. For this reason, the rolling load and rolling power applied to the rough rolling mill are reduced, and not only the energy saving effect is obtained, but also high pressure is possible, and the number of rough rolling stands is reduced from six to three. Is obtained.

(Embodiment) A preferred embodiment of the present invention is shown in FIGS.
This will be described with reference to FIG. FIG. 1 shows the overall arrangement of a hot strip rolling facility to which the present invention is applied.

The main equipment in FIG. 1 is a slab width adjusting rolling mill 31 for adjusting the width of a hot slab from the upstream side, and a descaling means for removing oxide scale on the surface of the slab 4 before rough rolling. A header 2 for injecting high-pressure water, a furnace for accommodating the unrolled slab 4 and adjusting the temperature of the slab 4 to a temperature suitable for the rough rolling 3, a draining pinch roller device for draining the surface of the slab 4 before the rough rolling 6, rough rolling equipment 7 for rough rolling of hot slab 4, cropper 10 for cutting the end of coarsely rolled slab 4, finish rolling equipment 13 for finish rolling rough slab 4 and finish rolling. Strip 18
The cooling device 16 for cooling the plate, the dividing shears 20, and the two winding machines 24 and 26 are sequentially arranged. Here, the rough rolling equipment 7 and the finish rolling equipment 13 are arranged in tandem. The distance between the two is the roughly-rolled slab 4
Are set and arranged so that they can be rolled over both. At this time, it is desirable that both are arranged close to each other.

The slab width adjusting rolling mill 31 for adjusting the width of the hot slab 4 is provided with a vertical roll 1, and the width of the slab 4 can be adjusted by the vertical roll 1. In the present embodiment, the width adjustment using the vertical roll 1 has been described, but the width adjustment may be performed using other width adjusting means, for example, a press tool having an inclined portion and a parallel portion.

The header 2 sprays high-pressure water onto the surface of the slab 4 to remove surface oxide scale. This is performed because the surface of the slab 4 before the rough rolling is oxidized and scale is generated, and if the rough rolling is performed as it is, the surface quality is impaired. Here, the descaling means by high-pressure water injection is shown, but other descaling means may be applied.

The furnace 3 is arranged on the entry side (upstream side) of the rough rolling equipment 7 and stores the unrolled portion of the slab 4 to keep the temperature. The slab 4 is transported in the furnace 3 by transport rollers 5 serving as slab transport means.
, And sent to the downstream rough rolling equipment 7. The inner wall of the furnace 3 is covered with a heat insulating material. Of course, a burner or an electric heater for heating the slab 4 may be provided. When the slab length is long, it may exceed 60 m. Here, it is desirable that the length of the furnace 3 be long enough to accommodate the unrolled portion of the slab 4. That is, it is preferable that the length is longer than the length of the slab 4 before the rough rolling, and it is preferable that the length is approximately equal to the length of the slab 4 before the rough rolling.
By setting the length of the furnace 3 to approximately the same length as the slab 4 before the rough rolling, the unrolled portion of the slab 4 can be stored in the furnace 3 from the initial state of the rough rolling. Thus, furnace 3
Thereby, the slab 4 which has not been roughly rolled can be stored and the temperature of the slab 4 can be adjusted to a temperature suitable for rough rolling.

The draining pinch roller device 6 drains the surface of the slab 4 before rough rolling and feeds the slab 4 to the rough rolling equipment 7 by the draining pinch rollers 39 arranged above and below the slab 4. The draining pinch roller device 6 can assist extra draining and biting of rough rolling.

In the present embodiment, the rough rolling equipment 7 includes three two-high rolling mills, and a width adjusting device 9 is disposed between the two high rolling mills. That is, from the upstream side, the two-high rolling mill 7
a, width adjusting device 9, two-high rolling mill 7b, width adjusting device 9, 2
The step rolling mill 7c was sequentially arranged.

The crop shears 10 are slab shearing means arranged on the exit side of the rough rolling equipment 7, and cut the ends of the roughly rolled slabs 4. In the present embodiment, a drum-type shearing means is used, and a pair of upper and lower rotary drums 12 and a shear blade 11 attached to the rotary drum 12 are provided. With this cropper 10, defective portions such as tongues and fish tails generated at the leading and trailing ends of the slab 4 after the rough rolling can be sheared.

In the present embodiment, the finishing rolling equipment 13 is provided with six four-high rolling mills, but this number can be set as appropriate. The finishing four-high rolling mill includes a pair of upper and lower work rolls 14 and a pair of upper and lower reinforcing rolls 15 that support the respective work rolls 14. The finish-rolling equipment 13 finish-rolls the roughly-rolled slab 4 into a strip 18.

The strip cooling device 16 is provided downstream of the finishing mill 13 and has a header 17 for injecting cooling water. Cooling water is sprayed from the header 17 onto the surface of the strip 18 that has been finish-rolled to cool the strip 18.

The split shaft 20 is provided with a shear blade 21 for shearing the strip 18 during running to produce a coil by winding, and a pair of upper and lower rotary drums 22 provided with the shear blade 21. Further, pinch rollers 19 for holding the band plate 18 at respective portions are disposed on the entrance side and the exit side of the split shear 20. When the coil diameter of the subsequent pinch roller 25 and the winder 26 reaches a predetermined value, the band plate 18 is held down by the pinch rollers 19 on the entrance side and the exit side of the division shears 20. Can be moved and split sheared.

The pinch roller 25 and the winding machine 26 are arranged so that the winding can be switched. The input side of the pinch roller 25 and the winder 26 are respectively provided with a pinch roller 23 and a winder 2 that convert in the winding direction.
4 was provided. By installing the pinch roller 25 and the winding machine 26, winding can be sequentially switched to perform efficient winding work. When approaching the end of winding, the strip 18 is sheared by the above-described dividing shears 20, and the remaining amount is wound up.
The strip 18 can be wound into a coil.

Next, the rolling operation of this facility will be described with reference to FIG. 1 and Table 1. Table 1 shows various data of rolling in this example.

[0033]

[Table 1]

The dimensions of the slab handled by this equipment are as follows: the thickness of the slab is about 100 to 260 mm, the width of the slab is about 600 to 1800 mm,
A slab 4 having a length of about 10 to 100 m before rough rolling.
Is about 1150-1250 ° C. for a normal carbon steel material. Such a slab 4 is usually manufactured by a slab continuous casting machine.

In this embodiment, first, a predetermined amount of width rolling is performed by the vertical roll 1 of the width adjusting rolling mill 31. The width rolling speed in this case is 80 to 120 m / min. After this width rolling, high pressure water is sprayed onto the surface of the slab 4 by the header 2 to remove oxide scale from the slab surface. As described above, since the oxide scale is removed before the slab 4 is carried into the furnace 3, the inside of the furnace can be kept clean without bringing the oxide scale into the furnace 3.

The slab 4 thus width-rolled is supplied to the furnace 3
Is transported by the transport rollers 5 and stored in the furnace 3. Of course, the furnace wall is provided with a heat insulating material, and is heated by a burner or an electric heater as necessary.
In this embodiment, the slab 4 before the rough rolling has a sheet thickness of 24.
5 mm and the temperature was 1200 ° C.

Next, the slab 4 in the furnace 3 is pushed into the rough rolling facility 7 by a draining pinch roller 39 at a speed of about 6.86 m / min.

The first two-high rolling mill 7a (R
In 1), a rolling power of 1370 kw and a rolling load of 1914 t
In step f, rough rolling was performed using a rough rolling roll 8 having a diameter of 1000 mm at a rolling reduction of 90 mm and a rolling reduction of 36.7%. At this time, the contact point of the roll surface was 212.3 mm, and the contact time during which one point of the roll was in contact with the slab 4 as a rolled material during one rotation of the roll was 1.18 sec / 1 rotation. By the rough rolling by such a two-high rolling mill 7a (R1), the thickness 1
A slab 4 of 55 mm was obtained, at which time the temperature of the slab 4 was 1178 ° C. After the rough rolling by the two-high rolling mill 7a (R1), the width is rolled by the width adjusting device 9, and the next rough rolling is performed. Here, the width adjusting device 9 adjusts the width and assists biting in the next rough rolling.

The next two-high rolling mill 7b (R
In 2), the rolling power is 3092 kw and the rolling load is 2558 t.
In step f, rough rolling was performed using a rough rolling roll 8 having a diameter of 1000 mm with a reduction of 77 mm and a reduction of 49.7%. At this time, the contact point of the roll surface was 196.8 mm, and the contact time was 0.549 sec.
/ 1 revolution. Such a two-high rolling mill 7b (R2)
Slab 4 having a thickness of 78 mm is obtained by rough rolling by
The temperature of the slab 4 at that time was 1152 ° C. In this embodiment, the second rough rolling mill is a two-high rolling mill 7 having a rough rolling roll 8 having the same diameter as the first rough rolling roll 8.
However, a rough rolling roll 8 having another diameter may be used, or a rolling mill having another number of stages may be used. After the rough rolling by the two-high rolling mill 7b (R2), the width is rolled by the width adjusting device 9, and the next rough rolling is performed. Here, the width adjusting device 9
Adjusts the width and assists biting into the next rough rolling.

The final two-high rolling mill 7c (R
In 3), the rolling power is 5654 kw and the rolling load is 2894 t.
In step f, rough rolling was performed using a rough rolling roll 8 having a diameter of 1000 mm with a reduction of 43 mm and a reduction of 55.1%. At this time, the contact point of the roll surface was 147.5 mm, and the contact time was 0.184 sec.
/ 1 revolution. Usually, the thickness is reduced to about 30 to 40 mm by rough rolling by the rough rolling equipment 7. In this example, a slab 4 having a thickness of 35 mm was obtained by rough rolling by a two-high rolling mill 7c (R3), and the temperature of the slab 4 at that time was 1126 ° C. In the present embodiment, the third rough rolling mill is a two-high rolling mill 7c provided with a rough rolling roll 8 having the same diameter as that of the first rough rolling roll 8, but a rough rolling roll of another diameter is used. 8 may be used, or a rolling mill having another number of stages may be used.

As described above, the rolling speed at the time of rough rolling is slow, that is, low-speed rolling.

After such a rough rolling, a defective portion called a tongue or a fish tail is formed at the leading and trailing ends of the slab 4, so that a pair of rotary drums 12 provided with a shearing blade 11 are rotated to rotate them. Crop cut the defective part. Next, finish rolling is performed by the finish rolling equipment 13.

In the present embodiment, in the rough rolling step and the finish rolling step, both the equipment (rough rolling equipment 7 and finish rolling equipment 13) are arranged so as to be shorter than the length of the slab 4 after the rough rolling. Therefore, the slab 4 is simultaneously rolled over both facilities. That is, since the rough rolling equipment 7 and the finishing rolling equipment 13 are arranged at intervals shorter than the length of the slab 4 after the rough rolling, the slab 4 is rolled over the rough rolling equipment 7 and the finishing rolling equipment 13. Is made.

In the finishing rolling equipment 13, the slab 4 after the rough rolling is transferred to a pair of work rolls 14 and a pair of reinforcing rolls 15.
Is rolled into a strip 18 by a train of six four-high rolling mills provided with The rolling speed in this case depends on the product thickness,
The thickness is about 1.2 mm and the rolling speed is about 1400 m / min.

The strip 18 after finish rolling is then cooled by cooling water flowing down from the header 17 of the strip cooling apparatus 16 to about 9 mm.
It is cooled from 00 ° C to around 600 ° C. Then, the strip 18 is wound around a coil by the first pinch roller 25 bent downward by the pin roller 23. When the size of the coil reaches a predetermined value, the strip 18 is rotated by the rotating drum 22 of the split shaft 20 having the shearing blade 21 while being sandwiched by the two pinch rollers 19, and is split and sheared. .
The strip 18 after shearing is bent downward by another winding machine 24 and wound around a coil by a second winding machine 26.

The rough rolling operation and the finish rolling operation are performed in such a manner that the unrolled portion of the slab 4 is accommodated in the furnace 3 on the entry side of the rough rolling equipment 7 and the stretched slab, ie, the rolled material, is rolled. 7 and finishing rolling equipment 13.

Next, the embodiment will be described in more detail with reference to FIGS. 2 and 3, which show details of an entrance-side facility which is a main object of the present invention in the hot strip rolling facility of FIG. FIG. 2 is a front view of the entrance equipment of the present invention, and FIG. 3 is a plan view of a cross section of the pass line in FIG. First, the drive shaft 30 of the vertical roll 1 is driven by a drive motor (not shown) to perform width adjustment rolling. Then, high-pressure water is injected from the upper and lower headers 2 to perform descaling. Thereafter, as described in the description of the equipment in FIG. 1, the slab 4 is transported and stored in the furnace 3 by the transport roller 5.

The slab 4 housed in the furnace 3 is centered with respect to a pass center before performing a rough rolling operation. That is, a roller 32 provided to face both width surfaces of the slab 4 is supported by a bearing box 33 that supports the roller 32.
Is performed by pressing the piston 35 with the cylinder 34 via.

Such a centering device is different depending on the length of the slab 4 to be handled. However, four centering devices are used for handling a long slab such as 60 to 100 m, and two for a short slab such as 10 to 20 m. Arrange around the table. As a matter of course, the member for pushing the width surface of the slab 4 may be a guide plate instead of the roller 32 as shown in the figure, and the guide plate may be of a long length so as to straddle two pressing devices. is there. Further, it goes without saying that the pressing actuator is not limited to a cylinder but may be a motor or a screw.

The slab 4 centered as described above
Is then conveyed into the draining pinch roller stand 38.
Here, a pair of upper and lower draining pinch rollers 39 is connected to the cylinder 36.
Is pressed against the slab surface by the piston 37, and draining is performed so that water after descaling with high-pressure water injected from the header 40 does not flow into the furnace.

At the same time, the slab is pushed into the first rough rolling roll 8 to assist biting into the rough rolling roll 8.
The pair of rough rolling rolls 8 is supported by a bearing box 60 and housed in a housing 63. In this, the upper roll is raised and lowered by a pressing down device 41, and the amount of reduction of the slab 4 is determined.

First rough rolling roll 8 (two-high rolling mill 7a)
Then, the slab 4 subjected to the thickness reduction rolling is then centered at its tip by a guide 51, and then subjected to width adjustment rolling by a width adjustment device 9 accommodated in a stand 49, and then subjected to a second rough rolling ( The two-high rolling mill 7b) is performed. The third rough rolling (two-high rolling mill 7c) may be performed if necessary.

That is, after the leading end of the rolled material is centered by the guide 50, the third rough rolling (two-high rolling mill 7c) is performed by the width adjusting device 9 and the rough rolling roll 8. Further, if necessary, the number of rough rolling mills may be increased.

As described above, the entry speed of the slab before the rough rolling is as low as 6.86 m / min. But furnace 3
The distance from the end of the roll to the first rough rolling roll 8 (two-high rolling mill 7a) can be as short as about 2500 mm because only the draining pinch roller stand 38 is disposed between them. Therefore, the heat radiation time from the slab surface can be shortened, and therefore, the temperature drop of the slab can be minimized.

Further, since rolling is performed at the high rolling reduction of 30% or more by the first rough rolling roll 8 (two-high rolling mill 7a), after this rolling stand, the traveling speed of the slab 4 as a rolled material is 10 m / m. min or more, and the heat radiation from the rolled material surface is suppressed.

In FIG. 4, the descaling header 54
Is arranged on the entry side of the width-adjusting rolling mill 31, and a horizontal stand provided with a horizontal rolling roll 53 is provided on the entry side of the furnace 3.

The horizontal rolling roll 53 can correct the deformation of the dock bone in the cross section generated at the time of width rolling of the slab to be flat, which is advantageous in smoothly passing the slab 4 into the furnace 3.

In FIG. 2, the three rough rolling mills are 2
Although an example in which a high-speed rolling mill is used has been described, a four-high-speed rolling mill in which a small-diameter work roll can be used can be disposed in the rough rolling mill on the delivery side. Further, it goes without saying that all of the rough rolling mills may be four-high rolling mills.

A furnace 43 may be provided between the rough rolling equipment 7 and the finishing rolling equipment 13 arranged in tandem.
An example is shown in FIG. FIG. 5 shows a hot strip rolling equipment arrangement according to another embodiment of the present invention.

In the arrangement shown in FIG. 5, a furnace 43 is provided between the rough rolling equipment 7 and the finishing rolling equipment 13 arranged in tandem. Specifically, the furnace 43 was provided on the upstream side of the cropper 10. This furnace 43 is used for the roughly rolled slab 4
Roller 45 as a transport means for transporting from the rough rolling equipment 7 to the finishing rolling equipment 13, and a heat retaining or heating means. The heat retaining or heating means may be provided with an insulated refractory on the inner wall of the furnace 43, or may be provided with a burner of heavy oil or gas or an electric heater as required.

The slab 4 to be roughly rolled is rolled across the rough rolling equipment 7 and the finish rolling equipment 13. By providing the furnace 43 for suppressing the heat radiation of the slab 4, the temperature decrease of the slab 4 before the finish rolling can be suppressed.

In this case, as compared with the arrangement example shown in FIG. 1, the length of the entire equipment must be lengthened and the furnace 43 must be added, but the existing equipment can be easily modified. There is.

That is, in the conventional hot strip rolling equipment, the distance between the rough rolling mill equipment and the finish rolling equipment is about 100 m. If such conventional equipment is to be modified into the equipment as shown in FIG. 1, a significant modification is required. However, in the arrangement of FIG. 5, the present invention can be applied while minimizing changes in existing equipment.

However, when the final finished plate thickness is relatively thick such as about 3 mm, or when the sheet thickness after rough rolling is as thick as about 45 mm, the heat shield type furnace 43 or the furnace The installation of 43 may be omitted. Here, the heat shield method is, for example, such that a heat insulating material is arranged at least close to the upper surface to suppress heat radiation of the slab material without heating the slab material after the rough rolling.

According to the above embodiment, the following effects can be obtained.

1) The hot rolling from the slab to the strip is carried out by tandem arrangement of the rough rolling equipment and the finish rolling equipment, and the rolled and stretched slab, that is, the rolled material is rolled over both. Although the speed of the slab at the entrance of the first rough rolling mill is extremely low, the unrolled slab at the entrance of the rough rolling equipment is stored in the furnace, so heat is radiated from the slab surface. Is suppressed, and the slab is prevented from lowering in temperature.

2) The width adjustment rolling performed on the entrance side of the first rough rolling mill of the rough rolling facility is performed by adjusting the width provided on the entrance side of the furnace for storing the unrolled portion slab provided on the entrance side of the rough rolling facility. The width adjustment rolling is performed by a rolling mill, and the width adjustment rolling can be performed at a high speed independent of the slab without straddling the first rough rolling mill. Therefore, heat radiation from the slab surface can be reduced.

3) As described above, since it is not necessary to arrange a width rolling mill between the first rough rolling mill of the rough rolling equipment and the end of the furnace for storing the unrolled slab, the minimum necessary equipment, that is, draining is performed. Since only the pinch roller stand and the descaling device need to be installed, the distance therebetween can be minimized. Therefore, heat radiation from the slab surface can be suppressed to a minimum.

4) Since the scale is descaled from the slab surface on at least one of the front and rear sides of the width adjusting rolling mill disposed in front of the furnace, the scale in the furnace is not brought in and the furnace is kept clean. We were able to.

5) 30% in the first rough rolling mill of the rough rolling equipment
Since the rolling is performed at the above high-pressure reduction rate, the speed of progress of the slab after the present rough rolling mill is increased, and even if the width-adjusting rolling mill is arranged on the entrance side of the second rough rolling mill, heat is radiated from the slab surface. And the width precision of the rolled material can be improved.

6) Since the rough rolling operation is performed at a low speed as described above, from the slab having a thickness of 245 m to the bar material having a diameter of 35 mm using three coarse rolling mills, despite the high rolling reduction, As shown in Table 1, rolling can be performed with a small rolling load and a small rolling power. That is, it is possible to configure a compact rough rolling facility.

[0072]

According to the present invention, the rough rolling equipment and the finish rolling equipment are arranged in tandem to reduce the space of the equipment and to suppress the temperature reduction of the hot slab.

[Brief description of the drawings]

FIG. 1 is an overall layout view of a hot strip rolling facility embodying the present invention.

FIG. 2 is a front view showing details of an entrance facility of FIG. 1;

FIG. 3 is a plan view of a cross section of the pass line in FIG. 2;

FIG. 4 shows another embodiment of the furnace width adjustment rolling equipment.

FIG. 5 shows a hot strip rolling equipment arrangement according to another embodiment of the present invention.

[Explanation of symbols]

1 ... vertical roll, 2, 17, 40 ... header, 3, 43 ...
Furnace, 4 slab, 5, 45 transport roller, 6 draining pinch roller device, 7 rough rolling equipment, 7a, 7b, 7c 2
Rolling mill, 8: rough rolling roll, 9: width adjusting device, 10 ...
Cropshafts, 11, 21 shear blades, 12, 22 rotating drums, 13 finish rolling equipment, 14 work rolls, 15
... Reinforcing roll, 16 ... Strip cooler, 18 ... Strip, 1
9, 23, 25 ... pinch rollers, 24, 26 ... winders, 30 ... drive shafts, 31 ... slab width adjusting rolling mills, 32 ...
Roller, 33, 60 ... bearing box, 34, 36 ... cylinder,
35, 37: Piston, 38: Drain pinch roller stand, 39: Drain pinch roller, 49: Stand, 51 ...
Guides, 53: horizontal rolling rolls, 54: descaling header, 61: pressing device, 63: housing.

Claims (8)

[Claims] (1) a rough rolling facility for roughly rolling a slab hot;
In a hot strip rolling equipment with a finish rolling equipment for producing a strip material by finishing rolling the slab that has been roughly rolled, the rough rolling equipment and the finish rolling equipment are arranged in tandem,
And the rough rolling equipment and the finish rolling equipment are arranged so that the slab is simultaneously rolled over the rough rolling equipment and the finishing rolling equipment, and furthermore, the slab is not provided on the entrance side of the rough rolling equipment. A hot strip rolling facility, comprising: a furnace for accommodating a slab in a rolling section; and a slab width adjusting rolling mill provided on an entrance side of the furnace. 2. The hot strip rolling equipment according to claim 1, wherein the width adjusting rolling mill and the rough rolling equipment are disposed far apart so that the slab does not roll over the slab. Hot strip rolling equipment. 3. The hot strip rolling equipment according to claim 1, wherein the rough rolling equipment has at least two rough rolling mills, and the first rough rolling mill on the entrance side among the at least two rough rolling mills. The width-adjusting rolling mill for adjusting the width of the slab is not arranged on the entrance side of the rolling mill, and the width-adjusting rolling mill for adjusting the width of the slab is arranged on the entrance side of the second and subsequent rough rolling mills. Strip rolling equipment. 4. The hot strip rolling equipment according to claim 3, wherein a draining pinch roller and a descaling are arranged between the furnace for storing the unrolled slab and the rough rolling equipment from an upstream side. And a hot strip rolling facility, wherein the hot strip rolling equipment is sequentially arranged. 5. The hot strip rolling equipment according to claim 1, wherein at least the inlet side of the entrance side and the exit side of the width adjusting rolling mill of the slab provided on the entrance side of the furnace for storing the unrolled portion. To
A hot strip rolling equipment comprising a descaling device for removing a scase from a slab surface. 6. The hot strip rolling equipment according to claim 1, wherein the first rough rolling mill of said rough rolling equipment performs a thickness reduction of 30% or more. . 7. A rough rolling step of roughly rolling a slab hot;
In the rolling method of the hot strip rolling equipment including the finish rolling step of manufacturing the strip material by finish rolling the slab that has been roughly rolled, before the rough rolling step, the width adjustment rolling is performed, and then the unrolled Hot rolling characterized by comprising a step of rough rolling while storing the slab of the part in a furnace, and a step of rolling the slab across a tandem-arranged rough rolling facility and a finish rolling facility. Rolling method of strip rolling equipment. 8. The method for rolling a hot strip rolling facility according to claim 7, wherein the rough rolling step includes a step of reducing the thickness by 30% or more in a first rolling mill of the rough rolling facility. A method of rolling hot strip rolling equipment, comprising: