JPH06320203A - Continuous casting/hot rolling equipment - Google Patents

Abstract

PURPOSE:To produce a hot strip with compact equipment on a small and intermediate scale by providing rolling mills having large diameter work rolls on the side of the preceding stage of hot rolling equipment and providing small diameter work rolls on the side of the succeeding stage. CONSTITUTION:Two rolling mills 8, 9 in the preceding stage of a finishing mill line 4 are taken as the rolling mills having the large diameter work rolls and the rolling mills which are arranged on the side of the succeeding stage than those rolling mills are provided with the work rolls whose diameters are smaller than the driving parts of the work rolls and cannot withstand driving torque necessary for rolling. These rolling mills are taken as small diameter work roll driven type rolling mills whose work rolls are driven with back-up rolls or intermediate rolls for supporting these work rolls. By arranging five rolling mills, for example, a slab 17 of about 40-80mm thick is rolled down to <=2.0mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous hot rolling mill for casting metal sheets.

[0002]

2. Description of the Related Art Continuation of a continuous casting process and a hot rolling process achieves significant energy saving and labor saving as compared with the conventional method in which a steelmaking factory and a rolling factory are separated. The number of facilities that have specifically adopted serialization is increasing.

The advantage of the continuous operation is that the temperature of the slab is not cooled as much as possible to reduce the reheating amount to reduce the energy consumption rate and the transportation of the slab between the steelmaking factory and the rolling factory. By eliminating it, labor saving can be achieved.

When the continuous casting process and the hot rolling process are continuous, the materials to be produced, the production amount, the method of obtaining the raw material, the equipment cost, the running cost, the energy consumption, the manufacturing labor cost, etc. are comprehensively examined. Therefore, it is desired that the optimum equipment be used.

As described above, when the continuous casting process and the hot rolling process are made continuous, they are roughly rolled by a rough rolling mill several times and then sent to a finishing rolling mill train to pass through the finishing rolling mill train once. There is a method of reducing the product sheet thickness to a product sheet thickness, and a method of eliminating the rough rolling machine and directly sending the slab to the finishing rolling machine row to pass the finishing rolling machine row once to reduce the product sheet thickness.

However, if the slab is thick, one row of rolling mills is used.
There is a limit to the method of passing the material through several times to reduce the thickness of the product. In order to reduce the rolling temperature by passing the rolling mill train once to 1.6 mm with only one pass through the 200 mm slab, the rolling temperature is increased and the rolling speed therefore increases. It is necessary to install a rough rolling mill without getting it.

Further, when the slab is thin, the rough rolling machine can be omitted, and there is a possibility of reduction of equipment cost and production cost. As one of the inventions of the method of casting this thin slab and making continuous casting and hot rolling continuous without using a roughing mill, for example, there is one described in JP-A-63-132703.

This article proposes a method of casting a relatively thin slab and performing a medium-scale production of about 1 million tons per year with a compact facility. In this case, maximum 3 to 4
Rolling is performed continuously with individual rolling roll stands, rolling with a large-diameter work roll in the first stage, driving work rolls or reinforcing rolls in the second stage, and slabs between continuous casting and hot rolling. Intermediate storage is disclosed.

[0009]

However, as for the thickness of the slab cast by the continuous casting apparatus, the fact that the slab has a thickness of about 50 mm or more has been practically used up to now.

Therefore, in the sheet described in the above publication, the sheet thickness required as the final product in hot rolling is 2.
If it is less than 0 mm, it cannot meet this need.

On the other hand, from the capability of the above continuous casting apparatus, the method of passing the rolling mill row once to reduce the product sheet thickness to 2.0 mm or less has a cost advantage over the method of arranging the rough rolling mill in terms of equipment. The significance of the existence of that method will diminish.

The present invention has been made in view of the above problems, and an object of the present invention is to produce a hot strip with compact equipment, so-called small and medium scale production which consumes less energy and has a low production unit. The object is to provide continuous casting hot rolling equipment capable of

[0013]

In order to achieve the above object, the present invention provides a hot casting machine equipped with a continuous casting facility and a plurality of rolling mills in a traveling direction of a slab cast by the continuous casting facility. In a casting hot rolling continuous equipment in which rolling equipment is arranged and the slab is continuously supplied to the hot rolling equipment and rolled into a predetermined shape, among the plurality of rolling machines of the hot rolling equipment, the former stage At least one rolling mill arranged on the side is a rolling mill provided with a work roll having a large diameter, and at least one rolling mill arranged on the subsequent stage side of the rolling mill has a drive unit for the work roll. The rolling mill is provided with a work roll having a small diameter that cannot withstand the driving torque required for rolling, and is driven by a reinforcing roll that supports the work roll.

Alternatively, in order to achieve the above object, in the present invention, a continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills are arranged in a traveling direction of a slab cast by the continuous casting facility. Then, in the casting hot rolling continuous equipment for continuously supplying the slab to the hot rolling equipment and rolling it into a predetermined shape, among the plurality of rolling mills of the hot rolling equipment, the hot rolling equipment is arranged at the front stage side. At least one rolling mill is a rolling mill equipped with large-diameter work rolls, and at least one rolling mill arranged on the rear stage side of the rolling mill has a work roll drive unit required for rolling. A work roll having a small diameter that cannot withstand the driving torque is provided, and an intermediate roll is arranged between the work roll and a reinforcing roll that supports a rolling load with a bearing portion,
The rolling mill is driven by an intermediate roll or a reinforcing roll.

In the above invention, the slab may be cut into a desired length and continuously supplied as a slab to the hot rolling equipment.

Further, in the present invention, a two-high rolling mill is used as the rolling mill having the large-diameter work roll, or the plate crown can be adjusted.

Further, according to the present invention, the rolling mill after the rolling mill having the large-diameter work roll is equipped with the work roll having a small diameter so that the driving portion of the work roll cannot withstand the driving torque required for rolling. In addition, a plurality of the rolling mills are arranged.

Further, according to the present invention, a rolling mill having a small-diameter work roll arranged at a stage subsequent to the rolling mill having the large-diameter work roll is a rolling mill whose plate crown and plate shape can be adjusted. Is.

Further, a high-speed steel roll is adopted as a work roll of at least one rolling mill in the rolling mill train of the hot rolling facility, or a roll polishing device is installed in the rolling mill.

Further, according to the present invention, a cutting machine for cutting the slab at an arbitrary length when the slab is cut at an arbitrary length and continuously supplied as a slab to the hot rolling facility. An induction heating furnace is arranged downstream of the slab so that the slab can be heated before the slab is cut.

[0021]

In general, the plate thickness that can be bitten is proportional to the radius of the work roll.

In the present invention, among the plurality of rolling mills of the hot rolling equipment, at least one rolling mill arranged on the preceding stage side is a rolling mill equipped with large-diameter work rolls.
The rolling mill having the large-diameter work rolls can bit a slab that is considered to be relatively thick as a finishing rolling mill train sent from the continuous casting equipment, and has a reduction in rolling force as compared with a rolling mill arranged in the subsequent stage. Large amount can be taken.

Further, according to the present invention, at least the work roll diameter capable of biting the plate material is provided at a stage subsequent to the rolling mill having the large-diameter work roll, and the drive unit can withstand the drive torque required for rolling. It is possible to strongly reduce the thin plate material by arranging a rolling mill that is a work roll having a diameter reduced to a size that cannot prevent the work roll and driving a reinforcing roll or an intermediate roll supporting the work roll.

Further, when the same reduction is performed, if the work roll diameter is small, the rolling load becomes small and the driving torque also becomes small.

In other words, if it is possible to carry out a strong reduction, the number of rolling mills can be reduced, and the thicker the material, the more it has the heat retaining ability, which enables rolling at a low speed.

Therefore, the hot strip can be made into a compact continuous casting hot rolling facility. Furthermore, since the rolling energy can be reduced, it is possible to provide a continuous casting hot rolling facility that consumes less energy and has a low production unit.

Further, a rolling mill equipped with large-diameter work rolls is arranged in front of the rolling mill train of the hot rolling facility, and this rolling mill is a two-stage rolling mill, or a rolling mill equipped with large-diameter work rolls. The rolling mill of the latter stage is a rolling mill having a working roll having a small diameter in which the driving part of the working roll cannot withstand the driving torque required for rolling, and a plurality of rolling mills are arranged to form a rolling mill row. By constructing two types of rolling mills, the equipment cost can be reduced and the maintainability can be improved.

Further, a rolling mill equipped with a large-diameter work roll in the preceding stage allows the plate crown to be adjusted, and a rolling mill subsequent to the rolling mill allows the plate crown and the plate shape to be adjusted, so that high-precision rolling is possible. Material can be provided.

Further, by adopting a high speed type roll as a work roll of the rolling mill train of the hot rolling equipment, it is possible to perform rolling at a high pressure and at a low speed, and further, by installing a roll polishing device in the rolling mill. The frequency of roll re-arrangement can be reduced even in rolling under severe conditions such as high pressure and low speed.

On the other hand, keeping the slab temperature at the rolling temperature and sending it to the rolling mill train is a necessary technique for obtaining the hot-rolled sheet material. Usually, the casting speed of the continuous casting machine is designed to minimize the reheating of the slab and is adjusted to the rolling temperature while utilizing the heat of the slab. However, the casting speed may be reduced as one of the countermeasures when a trouble occurs on the hot rolling equipment side. In this case, since the temperature of the slab is lowered in the continuous casting machine, the amount of reheating must be increased.

In the present invention, by placing an induction heating furnace at the rear of the cutting machine for cutting the slab in an arbitrary length, the slab can be heated before the slab is cut, and the slab can be heated. By raising the temperature and further installing an adiabatic furnace behind the induction heating furnace to prevent the heat of the slab from escaping to the outside as much as possible, it is possible to economically lengthen the continuous casting equipment and heat the equipment by sending it to the hot rolling equipment. It is possible to connect the hot rolling equipment.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
Will be explained.

FIG. 1 shows a casting hot rolling facility, which is a continuous casting facility 1 for continuously casting a slab 16.
A hot rolling equipment 7 having a rolling mill row 4 provided with a plurality of rolling mills is arranged in a traveling direction of a slab 16 cast by the continuous casting equipment 1.

Then, a cutting machine 2 for cutting the dummy bar portion at the head of the slab 16 cast by the continuous casting equipment 1 or for cutting the slab 17 of an arbitrary length, an induction heating furnace for heating the slab 17 20. An adiabatic furnace 3 is provided which displaces the cut dummy bar portion from the casting direction and supplies the slab 17 in a heat insulating state to a hot rolling facility 7 having a finish rolling mill row 4.

The hot rolling equipment 7 includes, in addition to the finishing rolling mill train 4, a width rolling mill 19 for adjusting the width of the slab 17, and a descaling device 2 for removing scales on the surface of the slab 17.
2, a cooling zone 5 for cooling the finish-rolled strip
And a down coiler 6 and the like.

The finishing rolling mill train 4 includes No. 1 stand 8, No. 2 stand 9, No. 3 stand 10, and No. 3 stand 10.
It is equipped with 5 stand tandem mill of 4 stand 11, No. 5 stand 12, No. 1 stand 8 and N.
The o.2 stand 9 is a two-high rolling mill having large-diameter work rolls, and the No. 3 stand 10 to the No. 5 stand 12 are four-high rolling mills.

FIG. 2 is a view of the casting hot rolling equipment shown in FIG. 1 as seen from above.

On the left side of the heat insulating furnace 3 in the traveling direction, a heat retaining furnace 13 is disposed between the continuous casting facility 1 and the hot rolling facility 7 to retain the slab for intermediate storage. The heat-retaining furnace 13 is used for dealing with troubles in the hot rolling equipment 7, and the slab 17 is cast to or from the heat-retaining furnace 13 while being lifted by the slab support arm 14. It can be carried to the line. The slab carried on the heat retention furnace 13 is clamped by the slab clamp device 15 and then stored in the heat retention furnace 13.

The adiabatic furnace burner 52 provided in the adiabatic furnace 3 heats the inside of the adiabatic furnace 3, and heats the furnace in the early stage of operation or when the temperature in the furnace is lowered in a timely manner. To do.

FIG. 3 is a view taken along the line AA in FIG. 1, and is for explaining the mechanism for carrying out the slab's regrowth (transporting from the casting line to the heat retaining furnace) and the method therefor. The slab support arm 14 includes arm support rollers 23, 2
4 and can be moved orthogonally to the casting line. On the other hand, a cylinder 32 for lifting the arm
The arm supporting roller 24 can be lifted so that the slab can be floated from the roller in the casting line and carried toward the heat retention furnace 13. The adiabatic furnace 3 has doors 25 and 26, and the temperature inside the adiabatic furnace 3 is prevented as much as possible by opening the slab when the slab is transported between the heat insulation furnace and the casting line.

The heat-retaining furnace 13 is covered with a heat-retaining furnace lid 27 so as to retain heat. When the slab 17 is carried, it can be opened and closed by the heat-retaining lid lifting device 28. There is.

The slab 17 in the heat insulation furnace 13 is stored so as to be superposed on the slab receiver 31, and the slab receiver 31 is moved up and down by the worm jack 30. This is a lid 27 for heat retention and a slab holder 31.
Between the slab holder 31 and the number of slabs 17 for better heat retention and transport of slabs.
To raise and lower.

Although not shown in the figure, the heat-retaining furnace 13 has a heating mechanism so that the slab 17 can be stored so that the temperature does not decrease.

FIG. 4 is a diagram showing the relationship between the position of B in FIG. 1, that is, the average temperature of the slab at the inlet of the induction heating furnace 20 and the casting speed.

Since the casting temperature is usually 4.0 m / min, the slab temperature at the inlet of the induction heating furnace 20 is equal to or higher than the slab target temperature, so reheating is not necessary. If the casting speed drops due to trouble, reheating is required. For example, if the casting speed falls to 2.5 m / min, it will be about 70
The temperature must be raised by ℃. Induction heating furnace 2
0 is used to reheat the slab in such a case.

FIG. 26 is a diagram showing an example of the relationship between the holding time and the temperature required to obtain an arbitrary cross-sectional shrinkage rate (RA), which is described in the document “Iron and Steel, 65th Year (1979)”. No. 14
FIG. 6 in “Paper-Embroidery characteristics of various steels with solidification structure in high temperature region”.

In this document, (1) embrittlement at a melting point to 1200 ° C., (2) embrittlement at 1200 ° C. to 900 ° C.,
(3) Embrittlement at 900 ° C. to 700 ° C. and the like are described. Regarding the embrittlement at 1200 ° C. to 900 ° C. of (2), S and O existing in supersaturation are (Fe, Mn) S, (Fe, Mn) O precipitates, and exhibits low ductility when tensile stress is applied in this state, and it is said that the precipitates become coarse and do not contribute to embrittlement due to constant temperature. Has been done.

In FIG. 26, it is shown that the larger the cross-sectional shrinkage rate (RA), the more ductile the material. The fact that this ductility is large means that the occurrence of defects such as cracks during rolling is reduced. The holding time required for the cross-sectional shrinkage ratio (RA) to be 60% is about 10 minutes when the material temperature is 900 ° C, and 1100 ° C.
In that case, it takes about 1.1 minutes, so holding at about 1100 ° C makes it easier to obtain a ductile material.

Therefore, the slag 17 is 1000 to 1200.
It can be said that it is preferable to hold the material in the range of ° C for a certain period of time and then supply it to the finishing compressor train.

Further, as described above, when the casting speed becomes slow, the temperature of the slab falls, so that reheating is required. However, the timing of this reheating is as early as possible to reduce the reheating amount, and It is possible to obtain a ductile material by making the distance between the continuous casting equipment and the hot rolling equipment 7 an economical length.

FIG. 5 is a diagram showing a continuous casting hot rolling facility according to a second embodiment of the present invention, and FIG. 6 is a diagram of FIG. 5 seen from above.

In the second embodiment shown in FIGS. 5 and 6, an induction heating furnace 29 is further arranged at the exit side position of the adiabatic furnace 3 of the first embodiment described with reference to FIGS. 1 and 2. .

When the slab 17 carried into the heat insulation furnace 3 from the heat retention furnace 13 requires reheating, or the induction heating furnace 2 after casting.
When the rolling temperature cannot be obtained even after passing through 0 and the adiabatic furnace 3, the slab 17 is reheated by the induction heating furnace 29 and is supplied to the hot rolling equipment 7 side to the hot rolling equipment 7. .

FIG. 7 is a diagram showing a continuous casting hot rolling facility according to a third embodiment of the present invention, and FIG. 8 is a diagram of FIG. 7 seen from above.

In the third embodiment shown in FIGS. 7 and 8, a soaking furnace 21 is arranged on the outlet side of the induction heating furnace 29 of the second embodiment described in FIGS. 5 and 6.

The soaking furnace burner 53 provided in the soaking furnace 21 is for heating the inside of the soaking furnace 21, and timely when the inside of the soaking furnace 21 is heated or the temperature of the inside of the furnace is lowered at the beginning of operation. It is to heat.

The soaking furnace 21 serves to make the temperature of the slab uniform.

As described above with reference to FIGS. 1 to 8, according to the first to third embodiments of the present invention, the slab 17 is kept at a predetermined rolling temperature and is transferred to the hot rolling equipment 7 side. It will be supplied.

Next, the finish rolling mill train 4 shown in the first to third embodiments of the present invention will be described.

FIG. 9 shows a first embodiment showing the concept of the roll size of the finishing rolling mill train 4, and FIG. 10 shows the finishing rolling mill train 4.
2 is a second embodiment showing the concept of roll size of FIG.
1 is a third embodiment showing the concept of the roll size of the finish rolling mill train 4.

In both cases, the two rolling mills at the front stage are rolling mills having large-diameter work rolls, and the rolling mills arranged at the rear stage side of the rolling mills require a drive unit for the work rolls for rolling. A small-diameter work roll driven rolling mill is provided with a work roll having a small diameter that cannot withstand a driving torque, and is driven by a reinforcing roll or an intermediate roll that supports the work roll.

First through third as shown in FIGS. 9 to 11.
In the embodiment of FIG.
It is possible to roll a slab of 0 mm to 80 mm to 2.0 mm or less.

FIG. 12 is a view in which the work roll diameters used for each evaluation of FIGS. 13 to 16 are arranged for each stand.

In FIGS. 12 to 16, the solid line a
Shows the case where all stands are driven by work rolls, and the broken line b
Shows the case where the two rolling mills in the preceding stage are large-diameter work rolls and each rolling mill behind the work rolls is a small-diameter work roll driven rolling mill. FIG. 13 is a diagram showing an example of a pass schedule when rolling with a rolling mill having the work roll diameter shown in FIG. 12, and from 70 mm to 1.6 mm, the rolling mill feed speed is 400 m / min in 5 passes. FIG. 14 shows the case of rolling, FIG. 14 shows the vertical total rolling torque of each stand when rolling in FIG. 12, and FIG. 15 shows the rolling load of each stand when rolling in FIG. FIG. 16 shows the motor power of each stand when rolling in FIG. 12.

Here, in the case of the solid line a, the No. 2 stand and the No. 4 stand are such that the diameter of the work roll is such that the drive part thereof can withstand the drive torque and is as small as possible. The work rolls of the No. 5 stand and No. 5 stand have the same work roll diameters as those of the No. 2 stand and No. 4 stand, respectively.

On the other hand, in the case of the broken line b, the diameter of the work roll of the No. 3 stand has a small diameter such that its drive unit cannot withstand the driving torque, and the work rolls of the No. 4 stand and the No. 5 stand have No. 3 Matched with the working roll diameter of the stand. However, even in this case, if the No. 3 stand cannot be bitten, stripping and rolling cannot be performed, so the constraint condition of the work roll diameter is this biting.

In the pass schedule of FIG. 13, N
o.3 Since the plate thickness on the stand entry side is about 14 mm, if the friction coefficient between the material and the work roll is 0.2, the minimum value of the work roll diameter is about 400 mm.

Here, the small diameter of the work roll will be described, which is such a size that the drive portion thereof cannot withstand the drive torque.

FIG. 17 is a diagram showing a work roll drivable region and a work roll drivable region. The solid line indicated by Tqc in the drawing shows the limit of the work roll drivable region. The area below Tqc is the work roll drivable area, and the area above Tqc is the work roll drivable area.

Therefore, in the upper and lower total rolling torque of FIG. 14, the No. 3 stand of the broken line b is located at the position of b-3 of FIG. 17, and similarly, the No. 4 stand and the N of the broken line b of FIG.
Since the o.5 stand is located at the position of b-4 and b-5 respectively, the above-mentioned No. 3 and 4 stands are shown in FIG.
It can be said that the rolling mill cannot drive the work rolls under the pass schedule shown in FIG.

Further, according to FIG. 15, the rolling load from the No. 3 stand to the No. 5 stand is broken line b with respect to solid line a.
It can be seen that the size of the rolling mill is smaller than that of 200 to 600 tons, the reinforcing roll can be made smaller, and a smaller rolling mill can be obtained.

Further, it can be seen from FIG. 16 that the motor power in the broken line b can be reduced by about 2000 kW, which is about 10% of the total motor power in the total of five stands, with respect to the solid line a.

FIG. 18 shows the average temperature of the strips at each stand when rolling with the rolling mill having the work roll diameter shown in FIG. The broken line b is higher than the solid line a by about 11 ° C. at the stand-out temperature of the No. 5 stand. Therefore, considering the strip rolling temperature, the broken line b shows the solid line a.
It is possible to lower the rolling speed. The fact that the rolling speed can be lowered in this way has a balance with the strip temperature, but it also leads to a reduction in the motor power.

FIG. 19 shows a fourth embodiment of the roll size of the finishing rolling mill train 4 and shows an example in which the slab thickness is 40 mm or less and the rolling mill train delivery side plate thickness is 2.0 mm or less.
In this case, one 2 stage rolling mill for large diameter work rolls is installed,
Three small-diameter work roll driven rolling mills are arranged behind it.

FIG. 20 shows a fifth embodiment of the roll size of the finishing rolling mill train 4 and shows an example in which the slab thickness is 150 mm and the rolling mill rolling-out side plate thickness is 2.0 mm or less. In this case, two two-high rolling mills with large-diameter work rolls and two four-high rolling mills with large-diameter work rolls were arranged behind them, and three small-diameter work roll driven rolling mills were arranged behind them. It is a thing.

If the slab thickness exceeds 150 mm, the rolling mills arranged in one row and continuously rolled in one pass would require an excessive amount of equipment. After the thickness is reduced, it is common to select a method of passing the finish rolling mill train once.

Next, a specific rolling mill applicable to the small diameter work roll driven rolling mill constituting the finishing rolling mill train 4 will be described.

The rolling mill shown in FIG. 21 is an example of a small-diameter work roll driven rolling mill.
The rolls 5 and 36 are movable in the axial direction. Further, a vertical roll bending force acts on the upper and lower work rolls 33, 34. In this case, the driving rolls are the upper and lower intermediate rolls 35 and 36 or the upper and lower reinforcing rolls 37 and 38.

Although not shown, the upper and lower intermediate rolls 35 and 36 may be provided with a roll bending force like the upper and lower work rolls 33 and 34.

By adopting the rolling mill as described above, it becomes possible to adjust the plate crown and the plate shape by the axial movement of the roll and the roll bending force.

Further, the upper and lower work rolls 33 and 34 can be movable in the axial direction similarly to the upper and lower intermediate rolls 35 and 36, and the work rolls are worn by periodically performing the axial movement of the work rolls. It is possible to disperse the rolls for a long period of time during which the rolls are used during rolling, and to achieve rolling with an excellent plate crown and plate shape.

The rolling mill shown in FIG. 22 is also an example of a small-diameter work roll driven rolling mill, in which the upper work roll 39 and the upper reinforcing roll 41 and the lower work roll 40 and the lower reinforcing roll 42 are moved up and down together. It is a rolling mill capable of crossing in opposite directions.

By thus crossing the rolls, the gap profile between the upper and lower work rolls can be changed, and the plate crown and the plate shape can be adjusted. In addition, although not shown, even in a rolling mill having a large-diameter work roll arranged in the preceding stage of the finishing rolling mill train 4, if the rolling mill is a four-high rolling mill, pair crossing is performed as described above, or only the upper and lower work rolls are in the opposite directions up and down. It is possible to change the gap profile between the upper and lower work rolls and adjust the plate crown by crossing the upper and lower work rolls. In the case of a two-high rolling mill, the upper and lower work rolls are crossed in opposite directions. By doing so, the same effect can be obtained.

The rolling mill shown in FIG. 23 is also an example of a small-diameter work roll driven rolling mill, in which the upper and lower work rolls 43 and 44 are non-driving rolls, and the driving roll is the upper and lower intermediate rolls 45 and 46. Upper and lower reinforcing rolls 47,
It is as 48. And the upper and lower work rolls 4
3, 44 or upper and lower intermediate rolls 45 and 46 or upper and lower reinforcing rolls 47 and 48, at least a pair of rolls, each having an initial crown of substantially the same shape so as to be point-symmetrical to each other.
The plate crown and plate shape can be adjusted by moving the rolls 5, 46 or the upper and lower work rolls 43, 44 in the axial direction similarly to the rolling mill shown in FIG. 21 or applying a roll bending force.

The rolling mill shown in FIG. 24 is also an example of a small-diameter work roll driven rolling mill. The upper and lower work rolls 49 and 50 are non-driving rolls, and the driving rolls are upper and lower reinforcing rolls 51 and 52. is there. The upper and lower work rolls 49, 50 and the upper and lower reinforcement rolls 51, 52 are provided with at least a pair of rolls each having an initial crown of substantially the same shape so as to be point-symmetrical to each other. The plate crown and the plate shape can be adjusted by moving the plate to the right or applying a roll bending force.

The rolling mill of the system shown in FIG. 24 can also be used in the rolling mill having the large-diameter work rolls arranged in the preceding stage of the finishing rolling mill train 4.

Further, the rolling mill shown in FIG. 25 is also an example of a small-diameter work roll driven rolling mill, and the upper and lower work rolls 53, 54 have other shafts 55, 54 whose axial centers are in contact with the work rolls 53, 54. Δ on the exit side in the rolling direction with respect to the axis of 56
Only the offset is made.

The driving tangential force F ₁ acting on the work rolls 53, 54 by offsetting in this way is the work roll 5
The horizontal component force F ₂ acting on the work rolls on the rolling direction entry side with respect to 3, 54 acts on the work rolls under the rolling load, and acts on the work rolling rolls exit side in the rolling direction. You can

A tension acts on the inlet and outlet sides of the strip 18, and by taking this force into consideration, the offset amount δ can be changed according to the rolling condition and adjusted so as to reduce the horizontal force acting on the work roll. Is done.

In addition, as the finishing rolling mill train 4 shown in FIGS. 9, 10, 11, and 20, a two-rolling mill having two two-rolling mills arranged on the preceding stage side is exemplified. By installing two rows side by side in one housing, the roll interval can be narrowed and the equipment length can be shortened.

Further, when a high speed steel roll having excellent wear resistance and surface roughening resistance, which has been widely applied as a hot rolling roll, is used, the wear amount is 1/4 to 1/5 of that of a conventional nickel grain roll. Since the number of rolls can be significantly reduced, the rolls can be used for a long time, and the roll reassembling cycle can be significantly extended.

Further, when the continuous casting equipment and the hot rolling equipment are connected to each other, the pressure may be high, the speed may be low, and the rolling of the same slab width may continue for a long time. Will be used. On the other hand, by installing a roll polishing device, it is possible to operate without shortening the roll changing cycle even if the roll wear increases.

[0093]

According to the present invention, it is possible to provide a continuous casting hot rolling facility capable of producing a hot strip on a small or medium scale with a compact facility.

[Brief description of drawings]

FIG. 1 is a diagram showing a continuous casting hot rolling facility according to a first embodiment of the present invention.

2 is a view of the continuous casting hot rolling equipment shown in FIG. 1 as viewed from above.

FIG. 3 is a view on arrow AA of FIG.

FIG. 4 is a diagram showing the relationship between the average temperature of the slab and the casting speed at position A in FIG.

FIG. 5 is a diagram showing a continuous casting hot rolling facility according to a second embodiment of the present invention.

6 is a view of the casting hot rolling continuous equipment shown in FIG. 4 as viewed from above.

FIG. 7 is a view showing a continuous casting hot rolling facility which is a third embodiment of the present invention.

FIG. 8 is a view of the continuous casting hot rolling equipment shown in FIG. 6 viewed from above.

FIG. 9 is a first embodiment showing the concept of roll size of the finish rolling mill train 4.

FIG. 10 is a second example showing the concept of the roll size of the finish rolling mill train 4.

FIG. 11 is a third example showing the concept of the roll size of the finish rolling mill train 4.

FIG. 12 is a diagram in which the work roll diameters used in each evaluation are arranged in each stand.

13 is a diagram showing an example of a pass schedule when rolling is performed by a rolling mill having the work roll diameter shown in FIG.

FIG. 14 is a diagram showing the total vertical rolling torque of each stand when rolling with a rolling mill having the work roll diameter shown in FIG. 12;

FIG. 15 is a diagram showing a rolling load of each stand when rolling by a rolling mill having the work roll diameter shown in FIG.

16 is a diagram showing a motor power of each stand when rolling is performed by a rolling mill having the work roll diameter shown in FIG.

FIG. 17 is an explanatory diagram illustrating a limit of a work roll drivable region.

FIG. 18 is a diagram showing an average strip temperature of each stand when rolling is performed by a rolling mill having the work roll diameter shown in FIG. 12.

FIG. 19 is a fourth example showing the concept of the roll size of the finish rolling mill train 4.

FIG. 20 is a fifth example showing the concept of the roll size of the finish rolling mill train 4.

FIG. 21 is a schematic view of a rolling mill applicable to a small-diameter work roll driven rolling mill constituting the finishing rolling mill train 4.

FIG. 22 is a schematic view of a rolling mill applicable to a small-diameter work roll driven rolling mill constituting the finishing rolling mill train 4.

FIG. 23 is a schematic view of a rolling mill applicable to a small-diameter work roll driven rolling mill that constitutes the finishing rolling mill train 4.

FIG. 24 is a schematic view of a rolling mill applicable to a small-diameter work roll driven rolling mill constituting the finishing rolling mill train 4.

FIG. 25 is a schematic view of a rolling mill applicable to a small-diameter work roll driven rolling mill that constitutes the finishing rolling mill train 4.

FIG. 26 is a diagram showing the relationship between the holding time and temperature required to obtain an arbitrary cross-sectional shrinkage rate (RA).

[Explanation of symbols]

1 ... Continuous casting equipment, 2 ... Cutting machine, 3 ... Adiabatic furnace, 4 ... Finishing mill row, 5 ... Strip cooling zone, 6 ... Down coiler, 7 ... Hot rolling equipment, 8 ... No. 1 stand, 9 ... N
o.2 stand, 10 ... No.3 stand, 11 ... N
o. 4 stand, 12 ... No. 5 stand, 13 ... Heat retaining furnace, 14 ... Slab support arm, 15 ... Slab clamp device, 16 ... Cast piece, 17 ... Slab, 18 ... Strip, 1
9 ... width rolling mill, 20 ... induction heating furnace, 21 ... soaking furnace, 22
... Descaling device, 23 ... Arm support roller, 24
... Arm support rollers, 25, 26 ... Doors, 27 ... Heat retention furnace lid, 28 ... Heat retention furnace lid lifting device, 29 ... Induction heating furnace, 30 ... Warm jack, 31 ... Slab receiver, 3
2 ... Arm lifting cylinder, 33 ... Upper work roll, 3
4 ... Lower work roll, 35 ... Upper intermediate roll, 36 ... Lower intermediate roll, 37 ... Upper reinforcing roll, 38 ... Lower reinforcing roll, 3
9, 49 ... upper work roll, 40, 50 ... lower work roll,
41, 47, 51 ... Upper reinforcing rolls, 42, 48, 52 ...
Lower reinforcing rolls, 43, 53 ... Upper working rolls, 44, 54
... Lower work rolls, 45, 55 ... Upper intermediate rolls, 46, 5
6 ... Lower intermediate roll, 57 ... Insulator furnace burner, 58 ... Soaking furnace burner.

Claims (34)

[Claims] 1. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills in a traveling direction of a cast product cast from the continuous casting facility are arranged, and the cast product is transferred to the hot rolling facility. In a continuous casting hot rolling facility for continuously supplying and rolling to a predetermined shape, among a plurality of rolling mills of the hot rolling facility, at least one rolling mill arranged on the preceding stage side has a large diameter. A rolling mill provided with work rolls, wherein at least one rolling mill arranged on the rear stage side of the rolling mill has a work roll having a small diameter such that a drive part of the work roll cannot withstand a driving torque required for rolling. And a continuous rolling machine for hot rolling of casting, comprising a rolling mill driven by a reinforcing roll supporting the work roll. 2. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills arranged in the traveling direction of the cast product cast by the continuous casting facility, and the cast product is cut to an arbitrary length. In the continuous casting hot rolling equipment for continuously supplying the slab as a slab to the hot rolling equipment and rolling it into a predetermined shape, among the plurality of rolling mills of the hot rolling equipment, it is arranged on the upstream side. At least one rolling mill provided is a rolling mill equipped with a work roll having a large diameter, and at least one rolling mill arranged on the subsequent stage side of the rolling mill requires a drive unit of the work roll for rolling. A continuous hot rolling mill for casting, comprising a work roll having a small diameter that cannot withstand various driving torques, and being driven by a reinforcing roll supporting the work roll. 3. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills arranged in a traveling direction of a cast product cast from the continuous casting facility, and the cast product is transferred to the hot rolling facility. In a continuous casting hot rolling facility for continuously supplying and rolling to a predetermined shape, among a plurality of rolling mills of the hot rolling facility, at least one rolling mill arranged on the preceding stage side has a large diameter. A rolling mill provided with work rolls, wherein at least one rolling mill arranged on the rear stage side of the rolling mill has a work roll having a small diameter such that a drive part of the work roll cannot withstand a driving torque required for rolling. A casting heat characterized by a rolling mill having an intermediate roll disposed between the work roll and a reinforcing roll supporting a rolling load with a bearing portion, and being driven by the intermediate roll or the reinforcing roll. Continuous rolling equipment. 4. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills in the advancing direction of the cast product cast from the continuous casting facility are arranged, and the cast product is cut to an arbitrary length. In the continuous casting hot rolling equipment for continuously supplying the slab as a slab to the hot rolling equipment and rolling it into a predetermined shape, among the plurality of rolling mills of the hot rolling equipment, it is arranged on the upstream side. At least one rolling mill provided is a rolling mill equipped with a work roll having a large diameter, and at least one rolling mill arranged on the subsequent stage side of the rolling mill requires a drive unit of the work roll for rolling. A work roll having a small diameter that cannot withstand various driving torques, an intermediate roll is arranged between the work roll and a reinforcing roll supporting a rolling load by a bearing portion, and the intermediate roll or the reinforcing roll is used for driving. That the rolling mill Characteristic continuous casting hot rolling equipment. 5. The continuous casting hot rolling equipment according to claim 1, wherein the small-diameter work rolls arranged on the rear side of the rolling mill equipped with the large-diameter work rolls are used. A continuous casting hot rolling facility characterized by arranging two or more rolling mills provided. 6. The continuous casting hot-rolling facility according to claim 1, wherein at least one of the rolling mills provided with the large-diameter work rolls arranged in the preceding stage has two stages. Continuous casting hot rolling facility characterized by being a rolling mill. 7. The continuous casting hot rolling facility according to claim 1, wherein a two-high rolling mill is used as a rolling mill equipped with a large-diameter work roll arranged in the preceding stage, and Two rolling mills are arranged, the work roll having the small diameter is arranged at a stage subsequent to the rolling mill, and a plurality of rolling mills are arranged to be driven by a reinforcing roll supporting the working rolls. Characteristic continuous casting hot rolling equipment. 8. The continuous casting hot rolling facility according to claim 3 or 4, wherein a two-stage rolling mill is used as a rolling mill equipped with a large-diameter work roll arranged in the preceding stage, and Two two-high rolling mills are arranged, the work roll having the small diameter is arranged at a stage subsequent to the two-high rolling mill, and an intermediate roll is arranged between the work roll and a reinforcing roll for supporting rolling load by a bearing portion. A continuous hot rolling casting facility, comprising a plurality of rolling mills driven by intermediate rolls or reinforcing rolls. 9. The continuous casting hot rolling equipment according to any one of claims 1 to 8, wherein the hot rolling equipment provided with a plurality of rolling mills has a plate thickness of 2.
A continuous casting hot rolling facility characterized by having the ability to roll down to 0 mm or less. 10. The continuous casting hot rolling equipment according to claim 1 or 2, wherein the slab supplied to the preceding rolling mill arranged in the hot rolling equipment has a thickness of 150 mm or less. A continuous hot-rolling facility for casting. 11. The continuous casting hot rolling facility according to claim 3 or 4, wherein the slab supplied to the preceding rolling mill arranged in the hot rolling facility has a thickness of 150 mm or less. The continuous hot-rolling equipment for casting, characterized in that 12. The continuous casting hot rolling facility according to claim 1, wherein at least one of the rolling mills equipped with the work roll having the large diameter is a rolling mill capable of controlling a plate crown. Machine for continuous hot rolling of casting. 13. The continuous casting hot rolling facility according to any one of claims 1 to 8, further comprising a small-diameter work roll disposed on the rear side of the rolling mill having the large-diameter work roll. The rolling mill is a rolling mill capable of controlling the strip crown and strip shape, and is a continuous casting hot rolling facility. 14. The continuous casting hot rolling facility according to claim 12, wherein at least one of the rolling mills provided with the work roll having the large diameter changes the gap between the rolls by crossing the upper and lower work rolls with each other. A continuous hot rolling mill for casting, characterized in that it is a rolling mill to obtain. 15. The continuous casting hot rolling facility according to any one of claims 1 to 4, 7 or 8, wherein the casting hot rolling continuous facility is arranged on a rear stage side of a rolling mill equipped with the large diameter work roll. The rolling mill provided with the small-diameter work rolls is a rolling mill having four or more stages, and is substantially the same for at least a pair of upper and lower work rolls, upper and lower intermediate rolls, and upper and lower reinforcing rolls of the rolling mill. Casting hot rolling characterized in that the shape-shaped initial crowns are given as point-symmetrical to each other, and further, the upper and lower work rolls or the upper and lower intermediate rolls can be moved in the roll axial direction to control the plate crown and the plate shape. Continuous equipment. 16. The continuous casting hot rolling facility according to claim 1, wherein the casting hot rolling continuous facility is arranged on a rear stage side of a rolling mill equipped with the large-diameter work rolls. The rolling mill equipped with the small-diameter work roll is configured so that the axial center of the upper and lower work rolls can be offset to the rolling-out side of the rolling center with respect to the axial center of another roll that comes into contact with the work roll, A continuous casting hot rolling facility characterized in that the driving tangential force can be reduced by the horizontal component of rolling load. 17. The continuous casting hot-rolling equipment according to claim 16, wherein the rolling mill configured to be offset to the rolling-out side of the rolling mill moves up and down with respect to the axis of another roll that comes into contact with the work roll. A continuous casting hot rolling facility, which is a rolling mill capable of adjusting an amount by which the axis of a work roll is offset to the rolling-out side. 18. The continuous casting hot rolling facility according to claim 1, wherein the casting hot rolling continuous facility is arranged at a rear stage of a rolling mill equipped with the large-diameter work rolls. The rolling mill provided with the small-diameter work roll is a rolling mill having four or more stages, and the work roll or the intermediate roll is provided with a roll bending device so that the deflection of the roll can be adjusted. Continuous hot-rolling equipment for casting, characterized in that the plate shape can be controlled. 19. The continuous casting hot rolling facility according to any one of claims 1 to 4, 7 or 8, wherein the casting hot rolling continuous facility is disposed on a rear stage side of a rolling mill equipped with the large-diameter work rolls. The rolling mill equipped with the small-diameter work roll is a four-high rolling mill, and the work roll and the reinforcing roll are paired up and down to make it possible to change the profile of the gap between the rolls. Continuous hot-rolling equipment for casting, characterized in that the plate shape can be controlled. 20. The continuous casting hot rolling facility according to any one of claims 1 to 4, 7 or 8, wherein the casting hot rolling continuous facility is arranged on a rear stage side of a rolling mill equipped with the large diameter work rolls. The rolling mill provided with the small-diameter work roll is configured to move the work roll in the roll axial direction to disperse the wear of the roll due to rolling and reduce the change in the roll gap due to wear, or A continuous casting hot rolling facility characterized in that in addition to movement in the roll axial direction, a work roll bending device is provided to adjust the deflection of the roll to control the strip crown and strip shape. 21. The continuous casting hot rolling facility according to claim 1, wherein the casting hot rolling continuous facility is arranged on a rear stage side of a rolling mill equipped with the large-diameter work rolls. The rolling mill provided with the small-diameter work roll is a six-high rolling mill, and moves the intermediate roll in the axial direction of the roll, or in addition to this, a roll bending device for the work roll or the intermediate roll. Is provided so that the roll crown and the strip shape can be controlled by adjusting the deflection of the roll. 22. The continuous casting hot rolling equipment according to claim 1, wherein the rolling mill equipped with the large-diameter work rolls is a two-high rolling mill. Is a set of upper and lower work rolls arranged in a row in the same housing, and the material passing through the rolling mill can be rolled a plurality of times in one pass. 23. The continuous casting hot rolling equipment according to claim 22, wherein the rolling mill having a plurality of pairs of upper and lower work rolls in the same housing is configured to cross at least one line of upper and lower work rolls. The continuous hot-rolling equipment for casting. 24. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills are arranged in a traveling direction of a cast product cast from the continuous casting facility, and the cast product is transferred to the hot rolling facility. In a continuous casting hot rolling facility for continuously supplying and rolling into a predetermined shape, a high speed steel roll is used as a work roll of at least one rolling mill in the rolling mill train of the hot rolling facility. Continuous casting hot rolling equipment. 25. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills are arranged in the traveling direction of the cast product cast by the continuous casting facility, and the cast product is cut to an arbitrary length. In a continuous casting hot-rolling facility for continuously supplying the slab as a slab to the hot-rolling facility and rolling it into a predetermined shape, work of at least one rolling mill in the rolling mill row of the hot-rolling facility Continuous casting hot rolling facility characterized by using high speed steel rolls. 26. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills are arranged in a traveling direction of a cast product cast from the continuous casting facility, and the cast product is transferred to the hot rolling facility. In a continuous casting hot rolling facility for continuously supplying and rolling to a predetermined shape, at least one rolling mill in the rolling mill train of the hot rolling facility is equipped with a roll polishing device. Continuous rolling equipment. 27. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills in the advancing direction of the cast product cast from the continuous casting facility are arranged, and the cast product is cut to an arbitrary length. As a slab, in the continuous casting hot rolling facility for continuously supplying the slab to the hot rolling facility and rolling it into a predetermined shape, at least one rolling mill in the rolling mill row of the hot rolling facility is rolled. A continuous casting hot rolling facility characterized by having a polishing device. 28. The casting hot rolling continuous equipment according to any one of claims 1 to 27, wherein rolling in the rolling mill train of the hot rolling equipment is performed under high pressure and at a low speed. Continuous casting hot rolling equipment. 29. A continuous casting facility and a hot rolling facility equipped with a plurality of rolling mills are arranged in a traveling direction of a cast product cast from the continuous casting facility, and the cast product is transferred to the hot rolling facility. In a continuous casting hot rolling facility for continuously supplying and rolling to a predetermined shape, after the slab is solidified, the slab is heated to a predetermined temperature by using a heating means capable of heating in a short time, and thereafter. A continuous hot-rolling facility for casting, characterized in that the heat of the slab is retained in an adiabatic furnace. 30. The continuous casting hot-rolling facility according to claim 29, wherein the heating means capable of heating in a short time is an induction heating furnace. 31. The continuous casting hot-rolling facility according to claim 29 or 30, wherein the adiabatic furnace also has heating means. 32. The continuous casting hot rolling equipment according to claim 29 or 30, wherein an induction heating furnace is provided on the downstream side of the adiabatic furnace before the slab is supplied to the hot rolling equipment. Continuous hot rolling equipment for casting, characterized in that the slab temperature is readjusted. 33. The continuous casting hot rolling equipment according to claim 32, wherein a soaking furnace is provided on the downstream side of the induction heating furnace, and the slab after cutting is soaked by the cutting machine. Characteristic continuous casting hot rolling equipment. 34. The continuous casting hot rolling facility according to claim 33, wherein the soaking furnace also has a heating means.